WO2013136303A1 - A positioning guide for positioning a bone cutting guide assembly and a bone cutting guide system - Google Patents

A positioning guide for positioning a bone cutting guide assembly and a bone cutting guide system Download PDF

Info

Publication number
WO2013136303A1
WO2013136303A1 PCT/IB2013/052070 IB2013052070W WO2013136303A1 WO 2013136303 A1 WO2013136303 A1 WO 2013136303A1 IB 2013052070 W IB2013052070 W IB 2013052070W WO 2013136303 A1 WO2013136303 A1 WO 2013136303A1
Authority
WO
WIPO (PCT)
Prior art keywords
bone
joint
guide
cutting guide
patient
Prior art date
Application number
PCT/IB2013/052070
Other languages
French (fr)
Inventor
John Robert HONIBALL
Original Assignee
Custom Med Orthopaedics Proprietary Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Custom Med Orthopaedics Proprietary Limited filed Critical Custom Med Orthopaedics Proprietary Limited
Publication of WO2013136303A1 publication Critical patent/WO2013136303A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/14—Surgical saws ; Accessories therefor
    • A61B17/15—Guides therefor
    • A61B17/154—Guides therefor for preparing bone for knee prosthesis
    • A61B17/155—Cutting femur
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/14—Surgical saws ; Accessories therefor
    • A61B17/15—Guides therefor
    • A61B17/154—Guides therefor for preparing bone for knee prosthesis
    • A61B17/157—Cutting tibia
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/16—Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans
    • A61B17/17—Guides or aligning means for drills, mills, pins or wires
    • A61B17/1739—Guides or aligning means for drills, mills, pins or wires specially adapted for particular parts of the body
    • A61B17/1764—Guides or aligning means for drills, mills, pins or wires specially adapted for particular parts of the body for the knee
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
    • A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
    • A61B17/88—Osteosynthesis instruments; Methods or means for implanting or extracting internal or external fixation devices
    • A61B17/8897—Guide wires or guide pins
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/16—Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans
    • A61B17/1662—Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans for particular parts of the body
    • A61B17/1675—Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans for particular parts of the body for the knee
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
    • A61B2017/568—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor produced with shape and dimensions specific for an individual patient

Definitions

  • This invention relates to a positioning guide for positioning a bone cutting guide assembly relative to a joint bone during a joint replacement surgical procedure.
  • the invention relates also to a bone cutting guide system for use in guiding the cutting of a patient's joint bone during joint bone replacement surgery.
  • replacement surgery and "replacement surgical procedure” must be interpreted sufficiently broadly to include a reference to bone resurfacing and bone resurfacing surgical procedure, respectively.
  • bone and “joint bone” must be interpreted to mean any elongate bone having a medullary canal, such as, for example, a femur, a tibia, a humerus, a radius, a finger bone or a toe bone.
  • a patient's joint bones may require replacement due to injury or deterioration caused by aging, or certain debilitating conditions, such as, for example, arthritis.
  • At least one prosthetic joint locating face must be cut in an end region of a joint bone by removing a portion of bone, so as to allow for the secure fitment of a prosthetic joint to the end region of the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint bone.
  • prosthetic joint locating faces are cut into a lower extremity of the femur and into an upper extremity of the tibia. More specifically, a number of flat femoral prosthetic joint locating faces are cut into the lower extremity of the femur along planes which are offset at predefined angles relative to one another.
  • a single flat tibial prosthetic joint locating face is typically cut into the upper extremity of the tibia.
  • the flat tibial prosthetic joint locating face is typically, but not necessarily, cut perpendicular with respect to a longitudinal axis of the tibia.
  • a prosthetic knee joint which is fitted to the patient during surgery comprises a femoral component and a tibial component.
  • the femoral and tibial components each comprise a generally cup-shaped receiving formation for receiving cut ends of the patient's femur and tibia, respectively.
  • the femoral component has a number of flat faces defined on inner sides of the receiving formation which are angularly offset with respect to one another, for abutting against corresponding flat prosthetic joint locating faces cut into the lower extremity of the femur. More particularly, when the femoral component is fitted to the cut femur of the patient such that the cut femur is received within the receiving formation of the femoral component, the angled faces of the femoral component abut corresponding angled joint locating faces cut on the lower extremity of the patient's femur, thereby to orientate the femoral component with respect to the femur in a predetermined orientation which approximates the anatomical normality of the patient's joint bone.
  • the tibial component has a flat locating face defined on an inner side of the receiving formation for abutting against the cut flat joint locating face cut into the upper extremity of the tibia. More particularly, when the tibial component is fitted to the cut tibia of the patient such that the cut tibia is received within the receiving formation of the tibial component, the flat prosthetic locating face of the tibial component abuts against the flat prosthetic joint locating face which was cut during surgery into the upper extremity of the tibia so as to orientate the tibial component with respect to the tibia in a predetermined orientation which approximates the anatomical normality of the patient's knee joint.
  • a so-called "bone cutting guide assembly” is used during surgery for guiding the cutting of a joint bone.
  • the bone cutting guide assembly is configured for guiding the cutting of a lower extremity of the patient's femur and an upper extremity of a patient's tibia. More particularly, the bone cutting guide assembly is configured for guiding the cutting of joint locating faces in end regions of a patient's distal femur or upper extremity of a patient's tibia to allow for the secure fitment of a prosthetic joint to the bone in a predetermined orientation which approximates the anatomical normality of the patient's knee joint.
  • the prosthetic joint In order to approximate anatomical normality of the patient's knee joint, it is necessary to align the prosthetic joint with respect to a mechanical axis of the patient's leg.
  • the mechanical axis of the leg extends through the centre of a head of the femur and through the centres of the knee and ankle joints of the leg.
  • the longitudinal axis of the femur In its anatomically normal position, the longitudinal axis of the femur is offset relative to the mechanical axis by an angle of deviation of approximately 6 Q .
  • a longitudinal axis of the tibia corresponds with the mechanical axis.
  • the bone cutting guide assembly In order to correctly orientate the bone cutting guide assembly relative to the joint bone, the bone cutting guide assembly must firstly be orientated with respect to some easily established reference.
  • the reference which is used is a longitudinal axis of the patient's femur.
  • the bone cutting guide assembly As a first step, the bone cutting guide assembly must thus firstly be orientated with respect to the longitudinal axis of the femur.
  • the bone cutting guide assembly must, as a second step, be orientated with respect to the mechanical axis of the femur, as determined from the longitudinal axis of the femur, so as to orientate the bone cutting guide assembly so as to guide the cutting of joint locating faces which will align the prosthetic joint optimally with respect to the mechanical axis of the leg.
  • the intramedullary rod is typically inserted into the medullary canal of the femur by hammering the intramedullary rod through a hole drilled into a lower extremity of the femur and along a length of a shaft of the femur and into the medullary canal of the femur.
  • the intramedullary rod is hammered into the bone such that the intramedullary rod frictionally engages the sidewalls of the bone which defines the medullary canal of the bone so as to anchor the intramedullary rod to the bone with a projecting end of the intramedullary rod projecting from the lower extremity of the patient's femur.
  • the femoral intramedullary rod typically has a length of between 200 mm to 400 mm and a diameter of approximately 8 mm.
  • the bone cutting guide assembly typically includes a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting a prosthetic joint locating face in an end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which has been inserted into a medullary canal of a patient's joint bone with the projecting end projecting from the bone.
  • the bone cutting guide is releasably mounted to the guide mounting means which is mounted to the intramedullary rod thereby releasably mounting the bone cutting guide relative to the patient's bone.
  • the guide mounting means is configured to control the position of the bone cutting guide relative to the longitudinal axis of the bone, as referenced by the intramedullary rod.
  • a bone cutting guide assembly Many different types are known.
  • One example of such a bone cutting guide assembly is described in US Patent 5,417,694.
  • the bone cutting guide assembly described in US 5,417,694 is configured for guiding the cutting of a patient's femur during knee replacement surgery.
  • the bone cutting guide assembly described in US 5,417,694 includes a bone cutting guide having at least one cutter guide formation in the form of a distal femoral cutting block for guiding a cutter for cutting a prosthetic joint locating face in an end region of a femur; and guide mounting means in the form of a valgus block and a stylus assembly which are releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially inserted into a medullary canal of a patient's femur such that a projecting end thereof projects from the femur.
  • the bone cutting guide guides the cutting of prosthetic joint locating faces in the femur and is releasably mounted to the valgus block and stylus assembly which is mounted to the intramedullary rod thereby releasably mounting the bone cutting guide relative to the patient's femur.
  • the valgus block and stylus assembly is releasably mounted to a projecting end portion of the intramedullary rod which is pre-inserted into the medullary canal of the patient's femur.
  • the distal femoral cutting block is then releasable mounted to the stylus so as to locate the distal femoral cutting block relative to the lower extremity of the femur.
  • the bone cutting guide is then fixedly secured to the femur by means of bone mounting pins and the intramedullary rod, and valgus block and stylus assembly are removed from the femur, leaving only the bone cutting guide mounted to the patient's femur.
  • the distal femoral cutting block of the bone cutting guide then guides surgical cutters used to cut a distal cut into the patient's distal femur to provide a first one of a series of joint locating faces cut into the femur.
  • the bone cutting guide assembly of the type described above suffers from a number of disadvantages. Firstly, the medullary canal of the patient often deviates from a longitudinal axis of the patient's bone, resulting in the intramedullary rod not being accurately aligned with the longitudinal axis of the bone. This is disadvantageous because the surgeon estimates the mechanical axis during surgery from the approximated longitudinal axis of the bone.
  • the intramedullary rod is invasive and destructive to the bone marrow of the patient, as the intramedullary rod must be deeply imbedded into the medullary canal of the patient, so as to anchor and align the intramedullary rod with respect to the medullary canal.
  • a positioning guide for positioning a bone cutting guide assembly relative to a patient's joint bone during a joint replacement surgical procedure for guiding the cutting of at least one prosthetic joint locating face in an end region of a joint bone of a human patient to allow for the secure fitment of a prosthetic joint to the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint
  • the bone cutting guide assembly including a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting said prosthetic joint locating face in said end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially insertable into a medullary canal of a patient's joint bone such that a projecting end thereof projects from the bone, the bone cutting guide being releasably mountable to the guide mounting means thereby to mount the bone cutting guide relative to the patient's bone, the positioning guide
  • a moulding which is constructed from anatomical data obtained of the end region of the joint bone so as to define locating formations which correspond to anatomical formations of the end region of the joint bone, thereby to provide for the secure fitment of the bone mounting structure to the end region of the joint bone wherein the profile of the complementary locating formations of the moulding conforms to the profile of the corresponding anatomical formations of the end region of the joint bone;
  • a pin-guiding formation which defines a guide passage having a predetermined orientation and spacial relationship relative to the moulding which is obtained from anatomical data of the position and orientation of the longitudinal axis of the joint bone for guiding the partial insertion of a reference pin into the joint bone along an axis which, after secure fitment of the moulding to the end region of the joint bone, has a predetermined spatial relationship with respect to at least one of a mechanical axis of the joint bone and a longitudinal axis of the joint bone, so as to provide for releasable mounting of the guide mounting means of the bone cutting guide assembly to a projecting end portion of the partially inserted reference pin, in use, thereby to facilitate accurate location of the bone cutting guide relative to the joint bone, for guiding the cutting of the prosthetic joint locating face in the joint bone.
  • the guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the longitudinal axis of the joint bone.
  • the guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the joint bone.
  • a bone cutting guide system for use in a joint replacement surgical procedure for guiding the cutting of at least one prosthetic joint locating face in an end region of a joint bone of a human patient to allow for the secure fitment of a prosthetic joint to the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint
  • the bone cutting guide system including: a reference pin which is configured to be at least partially inserted into an end region of a patient's joint bone; a bone cutting guide assembly including a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting said prosthetic joint locating face in said end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially insertable into a medullary canal of a patient's joint bone such that a projecting end thereof projects from the bone, the bone cutting guide being releasably mountable to the
  • a moulding which is constructed from anatomical data obtained of the end region of the joint bone so as to define locating formations which correspond to anatomical formations of the end region of the joint bone, thereby to provide for the secure fitment of the bone mounting structure to the end region of the joint bone wherein the profile of the complementary locating formations of the moulding conforms to the profile of the corresponding anatomical formations of the end region of the joint bone;
  • a pin-guiding formation which defines a guide passage having a predetermined orientation and spacial relationship relative to the moulding which is obtained from anatomical data of the position and orientation of the longitudinal axis of the joint bone for guiding the partial insertion of the reference pin into the joint bone along an axis which, after secure fitment of the moulding to the end region of the joint bone, has a predetermined spatial relationship with respect to at least one of a mechanical axis of the joint bone and a longitudinal axis of the joint bone, so as to provide for the releasable mounting of the guide mounting means of the bone cutting guide assembly to a projecting end portion of the partially inserted reference pin, in use, thereby to facilitate accurate location of the bone cutting guide relative to the joint bone, for guiding the cutting of the prosthetic joint locating face in the joint bone.
  • the guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with
  • the guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the joint bone.
  • the reference pin may have a penetrating formation which is configured to be inserted into the patient's bone.
  • the penetrating formation of the reference pin may have a length dimension which is preselected to ensure that the penetrating formation does not reach the medullary canal of the patient's bone when the penetrating formation is inserted into the end region of the patient's bone.
  • the penetrating formation of the reference pin may have a length dimension of between 10 mm and 40 mm.
  • the penetrating formation may have at least one anchoring formation for anchoring the reference pin to the patient's bone.
  • the anchoring formation may be in the form of a helical screw formation which is configured to be screwed into the patient's bone for anchoring the reference pin to the bone.
  • the penetrating formation may be formed by a centrally disposed cylindrical rod-like core which has the helical screw formation projecting radially outwardly therefrom.
  • a diameter of the cylindrical rod-like core may be less than half of a diameter of the helical screw formation. More specifically, the diameter of the cylindrical rod-like core may be approximately 3.5 mm. The diameter of the helical screw formation may be approximately 8 mm.
  • Figure 1 shows a perspective view of an outer side of a positioning guide in accordance with the invention
  • Figure 2 shows a perspective view of an inner side of the positioning guide of Figure 1 ;
  • Figure 3 shows a perspective view of the positioning guide of Figure 1 illustrating the manner in which the insertion of a reference pin is guided into a lower extremity of a patient's femur;
  • Figure 4 shows a perspective view of the femur of Figure 3, shown with the reference pin partially inserted into the femur;
  • Figure 5A shows an anterior view of the femur of Figure 4, showing a bone cutting guide assembly mounted to the reference pin;
  • Figure 5B shows the bone cutting guide assembly of Figure 5A, shown prior to being mounted to the reference pin shown in Figure 4A;
  • FIG. 6 shows an anterior view of another embodiment of a positioning guide in accordance with the invention, illustrating the manner in which the partial insertion of a reference pin is guided into an upper extremity of a patient's tibia.
  • a positioning guide in accordance with a first aspect of the invention is designated generally by the reference numeral 10.
  • the positioning guide 10 is configured for positioning a bone cutting guide assembly 12 (shown in Figures 5A and 5B of the drawings) relative to a lower extremity 4 of a femur 5 of a human patient's knee joint during a knee joint replacement surgical procedure.
  • the bone cutting guide assembly 12 is configured for guiding the cutting of joint locating faces in the lower extremity 4 of the femur 5 in order to allow for the secure fitment of a prosthetic joint (not shown) to the femur 5 in a predetermined orientation which approximates the anatomical normality of the patient's knee joint.
  • the bone cutting guide assembly 12 includes a bone cutting guide 13; and guide mounting means in the form of a valgus block and stylus assembly 15 for releasably mounting the bone cutting guide 13 to the femur 5, as will be explained in more detail below.
  • the bone cutting guide 13 has a dove-tail like recess 9 defined on an inner side thereof and a cutter guide formation in the form of a distal femoral cutting block 14 for guiding a cutter (not shown) for cutting a prosthetic joint locating face (not shown) in the lower extremity 4 of the femur 5.
  • the valgus block and stylus assembly 15 includes a valgus block 16 and a stylus 17, which are both illustrated in Figure 5B of the drawings; and a locking screw 18 illustrated in Figure 5A of the drawings.
  • the valgus block 16 has a rectangular prism shape and includes a pair of spaced apart apertures 19 extending therethrough; a central angled aperture 20 extending therethrough and a pair of lock nuts 21 , each lock nut threadably engages the valgus block 16 adjacent a different one of the pair of spaced apart apertures 19, the purpose of these features will be explained in more detail hereinbelow.
  • the central angled aperture 20 is angularly offset with respect to a line that is normal to the opposite parallel faces of the rectangular prism shaped valgus block 16 through which the aperture 20 extends. The reason for this will be explained in more detail hereinbelow.
  • the stylus 17 has a T-shaped configuration and includes a first carrying arm 22 and a second carrying arm 24.
  • the second carrying arm 24 extends perpendicularly from a middle region of the first carrying arm 22, as illustrated in Figure 5B of the drawings.
  • the first carrying arm 22 of the stylus 17 has a pair of upstanding posts 26 projecting upwardly therefrom.
  • the second carrying arm 24 of the stylus 17 has a pair of opposite parallel sides which have a beveled configuration such that the second carrying arm 24 forms a dove-tail type connector, the purpose of which will be explained in more detail hereinbelow.
  • the positioning guide 10 comprises a bone mounting structure 28 including a moulding 30 and a pin-guiding formation in the form of a cylindrical tubular guide formation 32.
  • the moulding 30 is constructed from anatomical data obtained from the lower extremity 4 of the femur 5 prior to surgery.
  • the moulding 30 is thus constructed prior to the surgical procedure, from anatomical data obtained by means of a radiographic scan of the lower extremity 4 of the patient's femur, from which scan, a three- dimensional model of the lower extremity 4 is constructed (not shown).
  • the moulding 30 defines locating formations 34 on an inner side thereof which correspond to anatomical formations 36 defined on the lower extremity 4 of the femur 5.
  • the locating formations 34 provide for secure fitment of the bone mounting structure 28 to the lower extremity 4 of the femur 5 in a specific position. More particularly, the profiles of the locating formations 34 of the moulding 30 conform to the profiles of corresponding anatomical formations of the lower extremity 4 of the femur 5.
  • the guide formation 32 defines a cylindrical guide passage 38 for guiding insertion of a reference pin 40 into the lower extremity 4 of the femur 5, when the bone mounting structure 28 is fitted to the femur 5, for reasons which will be explained in more detail hereinbelow.
  • the guide formation 32 has a predetermined orientation and spacial relationship relative to the moulding 30 and is integrally formed therewith. More specifically, the orientation and spacial relationship of the guide formation relative to the moulding, is obtained from the anatomical data obtained from a radiographic scan of the joint bone from which scan the position and orientation of the longitudinal axis of the joint bone is accurately ascertained.
  • the guide formation 32 guides insertion of the reference pin 40 along an axis accurately aligned with respect to a longitudinal axis 42 of the femur 5.
  • the positioning guide 10 provides for the location of the reference pin 40 relative to the femur 5 such that the reference pin 40 is accurately aligned with respect to the longitudinal axis 42 of the femur 5.
  • the positioning guide 10 provides for location of the valgus block and stylus assembly 15 of the bone cutting guide assembly 12, when the valgus block and stylus assembly 15 is releasably mounted to a projecting end portion of the partially inserted reference pin 40, in use, thereby to provide for the accurate location of the bone cutting guide 13 with respect to the patient's femur 5 at a predetermined position relative to the longitudinal axis 42 of the femur 5, so as to facilitate the cutting of prosthetic joint locating faces in the lower extremity 4 of the femur 5, thereby to provide for the fitment of the prosthetic joint thereto in a predetermined orientation which approximates the anatomical normality of the patient's joint.
  • the surgeon is able to adjust the positioning of the bone cutting guide 13 of the bone cutting guide assembly 12 such that the distal femoral cutting block 14 of the bone cutting guide 13 is located at a predetermined position, so as to guide the cutting of joint locating faces into the lower extremity 4 of the femur 5 which allow for the fitment of the prosthetic joint to the femur and furthermore for the correct orientation of the prosthetic joint with respect to the mechanical axis of the femur when the prosthetic joint is fitted thereto.
  • a surgeon will select a valgus block 16 from a library of valgus blocks.
  • Each valgus block is configured to compensate for a different so-called "valgus angle" of the patient, to produce a desired orientation of cuts into the patient's distal femur.
  • the selected valgus block is releasably mounted to the projecting end portion of the reference pin 40 by receiving the projecting end portion of the reference pin 40 within the central angled aperture 20 of the valgus block 16 and sliding the valgus block 16 down the reference pin 40 to the position shown in Figure 5A of the drawings.
  • the stylus 17 is then releasably mounted to the valgus block 16 by inserting the posts 26 projecting from the first carrying arm 22 of the stylus 17 through the pair of apertures 19 defined through the valgus block 16 and locking the lock nuts 21 such that each lock nut 21 clamps onto a different one of the pair of posts 26 for releasably mounting the stylus 17 and the valgus block 16 to one another.
  • the bone cutting guide 13 is then releasably mounted to the valgus block and stylus assembly 15, as shown in Figure 5A of the drawings, so as to locate the distal femoral cutting block 14 relative to the lower extremity 4 of the femur 5.
  • the second clamping arm 24 of the stylus 17 is slidingly received within a dove-tail type recess 9 defined on the inner side of the bone cutting guide 13, as best illustrated in Figure 5B of the drawings.
  • the bone cutting guide 13 is then fixedly secured to the femur by means of bone mounting pins (not shown). After the bone cutting guide 13 is fixedly secured to the femur 5, the reference pin 40, and the valgus block and stylus assembly 15 are then removed from the femur, leaving only the bone cutting guide 13 mounted to the patient's femur 5.
  • the distal femoral cutting block 14 of the bone cutting guide 13 guides surgical cutters used to cut a distal cut into the patient's distal femur to provide a first one of a series of joint locating faces cut into the femur, to provide for the fitment of the prosthetic joint thereto in a pre-determined configuration. For example, if a surgeon selects a 6° valgus block, a cut made on the anterior distal femur will be offset by 6° with reference to the longitudinal axis 42 of the patient's femur 5. This cut will also be normal to a mechanical axis of the patient's femur.
  • the distal cut thus defines the distal joint locating face which is then used to orientate other cutting guides (not shown), for guiding the cutting of a series of second and subsequent prosthetic joint locating faces which are cut into the lower extremity of the patient's femur.
  • the reference pin 40 has an overall length of between 100 mm to 120 mm.
  • the reference pin 40 has a penetrating formation which is configured to be inserted into the patient's bone.
  • the penetrating formation has a length of between 10 mm to 40 mm and defines an anchoring formation in the form of a helical screw formation which has a core diameter d 2 of approximately 3.5 mm and a helical screw diameter di of approximately 8 mm.
  • the penetrating formation of the reference pin 40 is particularly shorter, thinner and less invasive than the prior art femoral intramedullary rod described hereinabove. It will accordingly be appreciated that, in use, the insertion of the penetrating formation of the reference pin 40 into the lower extremity 4 of the femur 5 is thus less invasive than is the insertion of the femoral intramedullary rod into the medullary canal of the patient's femur.
  • the penetrating formation of the reference pin 40 has a length of between 10mm to 40mm the penetrating formation of the reference pin 40 particularly does not penetrate into the medullary canal of the femur, as the penetrating formation is too short to reach the medullary canal of the femur when the penetrating formation of the reference pin is inserted into the patient's bone.
  • the helical screw formation of the penetrating formation of the reference pin 40 enables the length of the penetrating formation to be of a relatively short length because the helical thread will provide for the anchoring of the reference pin 40 to the bone and, as such, it is not necessary for the penetrating formation of the reference pin 40 to extend deeply into the bone in order to anchor the reference pin 40 securely to the bone.
  • the reference pin 40 of the present invention is particularly accurately aligned with respect to the actual longitudinal axis 42 of the femur 5 which is determined from the anatomical data of the position and orientation of the longitudinal axis of the femur.
  • the positioning guide 10 provides a more accurate and less invasive means of positioning the bone cutting guide assembly 12 relative to the lower extremity 4 of the femur 5.
  • the guide passage may be configured for guiding the partial insertion of a reference pin into the femur along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the femur.
  • FIG. 6 of the drawings another example of a positioning guide in accordance with a first aspect of the invention, in the form of a tibial positioning guide, is designated generally by the reference numeral 100.
  • the tibial positioning guide 100 of Figure 6 is similar to the femoral positioning guide 10 of Figures 1 to 3 of the drawings, and as such, features of the tibial positioning guide 100 which are the same and/or similar to features of the femoral positioning guide 10 are indicated by the same and/or similar reference numerals. What is stated above with respect to the femoral positioning guide 10 applies generally to the tibial positioning guide 100.
  • the tibial positioning guide 100 is configured for positioning a bone cutting guide assembly (not shown) relative to an upper extremity 104 of a tibia 105 of a patient's knee joint during a joint replacement surgical procedure.
  • the tibial positioning guide 100 comprises a bone mounting structure 128 including a moulding 130 comprising a pair of moulding parts 130.1 , 130.2, a pin-guiding formation in the form of a guide formation 132 and a pair of arms 1 16 for connecting the guide formation 132 and the moulding parts 130.1 , 130.2 to one another in a predetermined orientation and spacial relationship.
  • the moulding parts 130.1 , 130.2 define complementary locating formations 134 on inner sides of the moulding parts 130.1 , 130, 2 which correspond to anatomical formations 136 defined on side regions of the tibia 105 and on end regions of the upper extremity 104 of the tibia 105, respectively.
  • the locating formations 134 provide for secure fitment of the bone mounting structure 128 to the tibia 105 in a specific position. More particularly, the profile of the locating formations 134 of the moulding parts 130.1 , 130.2 conform to the profile of corresponding anatomical formations of the tibia 105.
  • the guide formation 132 defines a cylindrical guide passage 138 for guiding insertion of a reference pin 140 into the tibia 105 when the bone mounting structure 128 of the tibial positioning guide 100 is fitted to the tibia 105, as shown in Figure 6 of the drawings.
  • the guide formation 132 has a predetermined orientation and spacial relationship relative to the moulding 130 and is integrally formed therewith. More specifically, the orientation and spacial relationship of the guide formation relative to the moulding, is obtained from the anatomical data obtained from a radiographic scan of the joint bone from which scan the position and orientation of the longitudinal axis of the joint bone is accurately ascertained.
  • the guide formation 132 guides insertion of the reference pin 140 along an axis accurately aligned with respect to the longitudinal axis 142 of the tibia 105.
  • the tibial positioning guide 100 provides for the accurate location of the reference pin 140 relative to the tibia 105 such that the reference pin 140 is accurately aligned with respect to a longitudinal axis 142 of the tibia 105.
  • the reference pin 140 provides an attachment to which guide mounting means of a tibial bone cutting guide assembly (not shown) can be releasably mounted, for releasably mounting a cutting guide of the tibial bone cutting guide assembly to the patient's tibia 105.
  • the invention extends to a bone cutting guide system in accordance with a second aspect of the invention, in the form of a femoral bone cutting guide system, is designated generally by the reference numeral 200.
  • the femoral bone cutting guide system 200 is configured for guiding the cutting of at least one prosthetic joint locating face in the lower extremity 4 of the patient's femur 5 to allow for the secure fitment of a prosthetic joint (not shown) to the femur in a predetermined orientation which approximates the anatomical normality of the patient's knee joint.
  • the femoral bone cutting guide system 200 includes the reference pin 40; the bone cutting guide assembly 12 and the femoral positioning guide 10 described hereinabove in accordance with the first aspect of the invention. It will be appreciated that the exact configuration of the femoral positioning guide 10, the tibial positioning guide 100 and the femoral bone cutting guide system 200, in accordance with the invention may vary greatly while still incorporating the essential features of the invention as described hereinabove.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Surgery (AREA)
  • Orthopedic Medicine & Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Medical Informatics (AREA)
  • Molecular Biology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Engineering & Computer Science (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Dentistry (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Physical Education & Sports Medicine (AREA)
  • Transplantation (AREA)
  • Prostheses (AREA)
  • Surgical Instruments (AREA)

Abstract

A femoral bone cutting guide system 200 includes a reference pin 40; a bone cutting guide assembly and a positioning guide 10 for positioning the assembly relative to a femur 5. The guide 10 includes a bone mounting structure 28 including a moulding and a guide formation 32. The moulding is constructed from anatomical data obtained from a radiographic scan of the femur 5 before surgery. The formation 32 has a predetermined orientation and spatial relationship relative to the moulding and defines a guide passage 38 which, after secure fitment of the moulding to the femur, guides insertion of the pin 40 into the femur 5 along a longitudinal axis of the femur. The pin 40 has a penetrating formation defining a helical screw formation for screwing the pin 40 into the femur 5. The assembly is mounted to a projecting end portion of the pin 40 which projects from the femur 5, for locating the assembly relative to the femur 5.

Description

A POSITIONING GUIDE FOR POSITIONING A BONE CUTTING GUIDE
ASSEMBLY AND A BONE CUTTING GUIDE SYSTEM
FIELD OF INVENTION
This invention relates to a positioning guide for positioning a bone cutting guide assembly relative to a joint bone during a joint replacement surgical procedure. The invention relates also to a bone cutting guide system for use in guiding the cutting of a patient's joint bone during joint bone replacement surgery. In this specification the terms "replacement surgery" and "replacement surgical procedure" must be interpreted sufficiently broadly to include a reference to bone resurfacing and bone resurfacing surgical procedure, respectively. In this specification the term "bone" and "joint bone" must be interpreted to mean any elongate bone having a medullary canal, such as, for example, a femur, a tibia, a humerus, a radius, a finger bone or a toe bone. BACKGROUND TO THE INVENTION
A patient's joint bones may require replacement due to injury or deterioration caused by aging, or certain debilitating conditions, such as, for example, arthritis.
During bone replacement surgery, at least one prosthetic joint locating face must be cut in an end region of a joint bone by removing a portion of bone, so as to allow for the secure fitment of a prosthetic joint to the end region of the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint bone.
More particularly, in the case of knee replacement surgery, prosthetic joint locating faces are cut into a lower extremity of the femur and into an upper extremity of the tibia. More specifically, a number of flat femoral prosthetic joint locating faces are cut into the lower extremity of the femur along planes which are offset at predefined angles relative to one another. A single flat tibial prosthetic joint locating face is typically cut into the upper extremity of the tibia. The flat tibial prosthetic joint locating face is typically, but not necessarily, cut perpendicular with respect to a longitudinal axis of the tibia.
A prosthetic knee joint which is fitted to the patient during surgery comprises a femoral component and a tibial component. The femoral and tibial components each comprise a generally cup-shaped receiving formation for receiving cut ends of the patient's femur and tibia, respectively.
The femoral component has a number of flat faces defined on inner sides of the receiving formation which are angularly offset with respect to one another, for abutting against corresponding flat prosthetic joint locating faces cut into the lower extremity of the femur. More particularly, when the femoral component is fitted to the cut femur of the patient such that the cut femur is received within the receiving formation of the femoral component, the angled faces of the femoral component abut corresponding angled joint locating faces cut on the lower extremity of the patient's femur, thereby to orientate the femoral component with respect to the femur in a predetermined orientation which approximates the anatomical normality of the patient's joint bone.
The tibial component has a flat locating face defined on an inner side of the receiving formation for abutting against the cut flat joint locating face cut into the upper extremity of the tibia. More particularly, when the tibial component is fitted to the cut tibia of the patient such that the cut tibia is received within the receiving formation of the tibial component, the flat prosthetic locating face of the tibial component abuts against the flat prosthetic joint locating face which was cut during surgery into the upper extremity of the tibia so as to orientate the tibial component with respect to the tibia in a predetermined orientation which approximates the anatomical normality of the patient's knee joint.
A so-called "bone cutting guide assembly" is used during surgery for guiding the cutting of a joint bone. In the case of knee surgery, the bone cutting guide assembly is configured for guiding the cutting of a lower extremity of the patient's femur and an upper extremity of a patient's tibia. More particularly, the bone cutting guide assembly is configured for guiding the cutting of joint locating faces in end regions of a patient's distal femur or upper extremity of a patient's tibia to allow for the secure fitment of a prosthetic joint to the bone in a predetermined orientation which approximates the anatomical normality of the patient's knee joint.
In order to approximate anatomical normality of the patient's knee joint, it is necessary to align the prosthetic joint with respect to a mechanical axis of the patient's leg. The mechanical axis of the leg extends through the centre of a head of the femur and through the centres of the knee and ankle joints of the leg. In its anatomically normal position, the longitudinal axis of the femur is offset relative to the mechanical axis by an angle of deviation of approximately 6Q. In its anatomically normal position, a longitudinal axis of the tibia corresponds with the mechanical axis.
In order to correctly orientate the bone cutting guide assembly relative to the joint bone, the bone cutting guide assembly must firstly be orientated with respect to some easily established reference. Typically, the reference which is used is a longitudinal axis of the patient's femur. As a first step, the bone cutting guide assembly must thus firstly be orientated with respect to the longitudinal axis of the femur. Once so orientated, the bone cutting guide assembly must, as a second step, be orientated with respect to the mechanical axis of the femur, as determined from the longitudinal axis of the femur, so as to orientate the bone cutting guide assembly so as to guide the cutting of joint locating faces which will align the prosthetic joint optimally with respect to the mechanical axis of the leg.
In order to establish a reference or datum for a longitudinal axis of a bone, it is common practice to insert an intramedullary rod into a medullary canal of the bone, sufficiently deeply so as to align the intramedullary rod with the medullary canal of the patient and such that a projecting end portion of the intramedullary rod is aligned with the medullary canal of the patient, so as to serve as a reference which approximates the longitudinal axis of the bone. It has been found, however, that for a relatively large number of patients, the medullary canal is not accurately aligned with the longitudinal axis of the bone. More particularly, it has also been found that for certain patients, the medullary canal serves as a particularly poor reference or datum of the longitudinal axis of the bone.
In the case of a femoral intramedullary rod, the intramedullary rod is typically inserted into the medullary canal of the femur by hammering the intramedullary rod through a hole drilled into a lower extremity of the femur and along a length of a shaft of the femur and into the medullary canal of the femur. More particularly, the intramedullary rod is hammered into the bone such that the intramedullary rod frictionally engages the sidewalls of the bone which defines the medullary canal of the bone so as to anchor the intramedullary rod to the bone with a projecting end of the intramedullary rod projecting from the lower extremity of the patient's femur. The femoral intramedullary rod typically has a length of between 200 mm to 400 mm and a diameter of approximately 8 mm. The bone cutting guide assembly typically includes a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting a prosthetic joint locating face in an end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which has been inserted into a medullary canal of a patient's joint bone with the projecting end projecting from the bone. The bone cutting guide is releasably mounted to the guide mounting means which is mounted to the intramedullary rod thereby releasably mounting the bone cutting guide relative to the patient's bone. The guide mounting means is configured to control the position of the bone cutting guide relative to the longitudinal axis of the bone, as referenced by the intramedullary rod.
Many different types of a bone cutting guide assembly are known. One example of such a bone cutting guide assembly is described in US Patent 5,417,694. The bone cutting guide assembly described in US 5,417,694 is configured for guiding the cutting of a patient's femur during knee replacement surgery. The bone cutting guide assembly described in US 5,417,694, includes a bone cutting guide having at least one cutter guide formation in the form of a distal femoral cutting block for guiding a cutter for cutting a prosthetic joint locating face in an end region of a femur; and guide mounting means in the form of a valgus block and a stylus assembly which are releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially inserted into a medullary canal of a patient's femur such that a projecting end thereof projects from the femur. The bone cutting guide guides the cutting of prosthetic joint locating faces in the femur and is releasably mounted to the valgus block and stylus assembly which is mounted to the intramedullary rod thereby releasably mounting the bone cutting guide relative to the patient's femur.
In use, the valgus block and stylus assembly is releasably mounted to a projecting end portion of the intramedullary rod which is pre-inserted into the medullary canal of the patient's femur. The distal femoral cutting block is then releasable mounted to the stylus so as to locate the distal femoral cutting block relative to the lower extremity of the femur. The bone cutting guide is then fixedly secured to the femur by means of bone mounting pins and the intramedullary rod, and valgus block and stylus assembly are removed from the femur, leaving only the bone cutting guide mounted to the patient's femur. The distal femoral cutting block of the bone cutting guide then guides surgical cutters used to cut a distal cut into the patient's distal femur to provide a first one of a series of joint locating faces cut into the femur. The bone cutting guide assembly of the type described above suffers from a number of disadvantages. Firstly, the medullary canal of the patient often deviates from a longitudinal axis of the patient's bone, resulting in the intramedullary rod not being accurately aligned with the longitudinal axis of the bone. This is disadvantageous because the surgeon estimates the mechanical axis during surgery from the approximated longitudinal axis of the bone. As a result, the estimated mechanical axis will be inaccurate leading to the surgeon making cuts to the bone, which do not optimally orientate the prostheses with respect to the actual mechanical axis of the bone. Secondly, the intramedullary rod is invasive and destructive to the bone marrow of the patient, as the intramedullary rod must be deeply imbedded into the medullary canal of the patient, so as to anchor and align the intramedullary rod with respect to the medullary canal.
A need therefore exists for a surgical tool which can accurately and securely locate the distal femoral cutting block of a bone cutting guide assembly relative to the lower extremity of the femur, in a less invasive manner than is the case with the abovementioned joint replacement surgical procedure using an intramedullary rod.
SUMMARY OF INVENTION
According to a first aspect of the invention, there is provided a positioning guide for positioning a bone cutting guide assembly relative to a patient's joint bone during a joint replacement surgical procedure for guiding the cutting of at least one prosthetic joint locating face in an end region of a joint bone of a human patient to allow for the secure fitment of a prosthetic joint to the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint, the bone cutting guide assembly including a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting said prosthetic joint locating face in said end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially insertable into a medullary canal of a patient's joint bone such that a projecting end thereof projects from the bone, the bone cutting guide being releasably mountable to the guide mounting means thereby to mount the bone cutting guide relative to the patient's bone, the positioning guide comprising: a bone mounting structure including:
(a) a moulding which is constructed from anatomical data obtained of the end region of the joint bone so as to define locating formations which correspond to anatomical formations of the end region of the joint bone, thereby to provide for the secure fitment of the bone mounting structure to the end region of the joint bone wherein the profile of the complementary locating formations of the moulding conforms to the profile of the corresponding anatomical formations of the end region of the joint bone; and
(b) a pin-guiding formation which defines a guide passage having a predetermined orientation and spacial relationship relative to the moulding which is obtained from anatomical data of the position and orientation of the longitudinal axis of the joint bone for guiding the partial insertion of a reference pin into the joint bone along an axis which, after secure fitment of the moulding to the end region of the joint bone, has a predetermined spatial relationship with respect to at least one of a mechanical axis of the joint bone and a longitudinal axis of the joint bone, so as to provide for releasable mounting of the guide mounting means of the bone cutting guide assembly to a projecting end portion of the partially inserted reference pin, in use, thereby to facilitate accurate location of the bone cutting guide relative to the joint bone, for guiding the cutting of the prosthetic joint locating face in the joint bone.
The guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the longitudinal axis of the joint bone.
In another embodiment, the guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the joint bone. According to a second aspect of the invention, there is provided a bone cutting guide system for use in a joint replacement surgical procedure for guiding the cutting of at least one prosthetic joint locating face in an end region of a joint bone of a human patient to allow for the secure fitment of a prosthetic joint to the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint, the bone cutting guide system including: a reference pin which is configured to be at least partially inserted into an end region of a patient's joint bone; a bone cutting guide assembly including a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting said prosthetic joint locating face in said end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially insertable into a medullary canal of a patient's joint bone such that a projecting end thereof projects from the bone, the bone cutting guide being releasably mountable to the guide mounting means thereby to releasably mount the bone cutting guide relative to the patient's bone; and a positioning guide comprising a bone mounting structure including :
(a) a moulding which is constructed from anatomical data obtained of the end region of the joint bone so as to define locating formations which correspond to anatomical formations of the end region of the joint bone, thereby to provide for the secure fitment of the bone mounting structure to the end region of the joint bone wherein the profile of the complementary locating formations of the moulding conforms to the profile of the corresponding anatomical formations of the end region of the joint bone; and
(b) a pin-guiding formation which defines a guide passage having a predetermined orientation and spacial relationship relative to the moulding which is obtained from anatomical data of the position and orientation of the longitudinal axis of the joint bone for guiding the partial insertion of the reference pin into the joint bone along an axis which, after secure fitment of the moulding to the end region of the joint bone, has a predetermined spatial relationship with respect to at least one of a mechanical axis of the joint bone and a longitudinal axis of the joint bone, so as to provide for the releasable mounting of the guide mounting means of the bone cutting guide assembly to a projecting end portion of the partially inserted reference pin, in use, thereby to facilitate accurate location of the bone cutting guide relative to the joint bone, for guiding the cutting of the prosthetic joint locating face in the joint bone. The guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the longitudinal axis of the joint bone.
In another embodiment, the guide passage may be configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the joint bone.
The reference pin may have a penetrating formation which is configured to be inserted into the patient's bone. The penetrating formation of the reference pin may have a length dimension which is preselected to ensure that the penetrating formation does not reach the medullary canal of the patient's bone when the penetrating formation is inserted into the end region of the patient's bone. The penetrating formation of the reference pin may have a length dimension of between 10 mm and 40 mm. The penetrating formation may have at least one anchoring formation for anchoring the reference pin to the patient's bone. The anchoring formation may be in the form of a helical screw formation which is configured to be screwed into the patient's bone for anchoring the reference pin to the bone. The penetrating formation may be formed by a centrally disposed cylindrical rod-like core which has the helical screw formation projecting radially outwardly therefrom. A diameter of the cylindrical rod-like core may be less than half of a diameter of the helical screw formation. More specifically, the diameter of the cylindrical rod-like core may be approximately 3.5 mm. The diameter of the helical screw formation may be approximately 8 mm. BRIEF DESCRIPTION OF THE DRAWINGS
Further features of the invention are described hereinafter by way of a non-limiting example of the invention, with reference to and as illustrated in the accompanying diagrammatic drawings. In the drawings:
Figure 1 shows a perspective view of an outer side of a positioning guide in accordance with the invention;
Figure 2 shows a perspective view of an inner side of the positioning guide of Figure 1 ;
Figure 3 shows a perspective view of the positioning guide of Figure 1 illustrating the manner in which the insertion of a reference pin is guided into a lower extremity of a patient's femur;
Figure 4 shows a perspective view of the femur of Figure 3, shown with the reference pin partially inserted into the femur;
Figure 5A shows an anterior view of the femur of Figure 4, showing a bone cutting guide assembly mounted to the reference pin;
Figure 5B shows the bone cutting guide assembly of Figure 5A, shown prior to being mounted to the reference pin shown in Figure 4A; and
Figure 6 shows an anterior view of another embodiment of a positioning guide in accordance with the invention, illustrating the manner in which the partial insertion of a reference pin is guided into an upper extremity of a patient's tibia. DETAILED DESCRIPTION OF THE DRAWINGS With reference to Figures 1 to 5 of the drawings, a positioning guide in accordance with a first aspect of the invention, is designated generally by the reference numeral 10.
The positioning guide 10 is configured for positioning a bone cutting guide assembly 12 (shown in Figures 5A and 5B of the drawings) relative to a lower extremity 4 of a femur 5 of a human patient's knee joint during a knee joint replacement surgical procedure.
The bone cutting guide assembly 12 is configured for guiding the cutting of joint locating faces in the lower extremity 4 of the femur 5 in order to allow for the secure fitment of a prosthetic joint (not shown) to the femur 5 in a predetermined orientation which approximates the anatomical normality of the patient's knee joint. The bone cutting guide assembly 12 includes a bone cutting guide 13; and guide mounting means in the form of a valgus block and stylus assembly 15 for releasably mounting the bone cutting guide 13 to the femur 5, as will be explained in more detail below.
The bone cutting guide 13 has a dove-tail like recess 9 defined on an inner side thereof and a cutter guide formation in the form of a distal femoral cutting block 14 for guiding a cutter (not shown) for cutting a prosthetic joint locating face (not shown) in the lower extremity 4 of the femur 5.
The valgus block and stylus assembly 15 includes a valgus block 16 and a stylus 17, which are both illustrated in Figure 5B of the drawings; and a locking screw 18 illustrated in Figure 5A of the drawings.
The valgus block 16 has a rectangular prism shape and includes a pair of spaced apart apertures 19 extending therethrough; a central angled aperture 20 extending therethrough and a pair of lock nuts 21 , each lock nut threadably engages the valgus block 16 adjacent a different one of the pair of spaced apart apertures 19, the purpose of these features will be explained in more detail hereinbelow. The central angled aperture 20 is angularly offset with respect to a line that is normal to the opposite parallel faces of the rectangular prism shaped valgus block 16 through which the aperture 20 extends. The reason for this will be explained in more detail hereinbelow.
The stylus 17 has a T-shaped configuration and includes a first carrying arm 22 and a second carrying arm 24. The second carrying arm 24 extends perpendicularly from a middle region of the first carrying arm 22, as illustrated in Figure 5B of the drawings. The first carrying arm 22 of the stylus 17 has a pair of upstanding posts 26 projecting upwardly therefrom. The second carrying arm 24 of the stylus 17 has a pair of opposite parallel sides which have a beveled configuration such that the second carrying arm 24 forms a dove-tail type connector, the purpose of which will be explained in more detail hereinbelow.
The positioning guide 10 comprises a bone mounting structure 28 including a moulding 30 and a pin-guiding formation in the form of a cylindrical tubular guide formation 32. The moulding 30 is constructed from anatomical data obtained from the lower extremity 4 of the femur 5 prior to surgery. The moulding 30 is thus constructed prior to the surgical procedure, from anatomical data obtained by means of a radiographic scan of the lower extremity 4 of the patient's femur, from which scan, a three- dimensional model of the lower extremity 4 is constructed (not shown).
The moulding 30 defines locating formations 34 on an inner side thereof which correspond to anatomical formations 36 defined on the lower extremity 4 of the femur 5. The locating formations 34 provide for secure fitment of the bone mounting structure 28 to the lower extremity 4 of the femur 5 in a specific position. More particularly, the profiles of the locating formations 34 of the moulding 30 conform to the profiles of corresponding anatomical formations of the lower extremity 4 of the femur 5. The guide formation 32 defines a cylindrical guide passage 38 for guiding insertion of a reference pin 40 into the lower extremity 4 of the femur 5, when the bone mounting structure 28 is fitted to the femur 5, for reasons which will be explained in more detail hereinbelow.
The guide formation 32 has a predetermined orientation and spacial relationship relative to the moulding 30 and is integrally formed therewith. More specifically, the orientation and spacial relationship of the guide formation relative to the moulding, is obtained from the anatomical data obtained from a radiographic scan of the joint bone from which scan the position and orientation of the longitudinal axis of the joint bone is accurately ascertained.
After secure fitment of the bone mounting structure 28 to the lower extremity 4 of the femur 5, as shown in Figure 3 of the drawings, such that the complementary locating formations 34 of the moulding 30 are aligned with the corresponding anatomical formations 36 of the lower extremity 4 of the femur 5, the guide formation 32 guides insertion of the reference pin 40 along an axis accurately aligned with respect to a longitudinal axis 42 of the femur 5. In use, the positioning guide 10 provides for the location of the reference pin 40 relative to the femur 5 such that the reference pin 40 is accurately aligned with respect to the longitudinal axis 42 of the femur 5. More particularly, in use, the positioning guide 10 provides for location of the valgus block and stylus assembly 15 of the bone cutting guide assembly 12, when the valgus block and stylus assembly 15 is releasably mounted to a projecting end portion of the partially inserted reference pin 40, in use, thereby to provide for the accurate location of the bone cutting guide 13 with respect to the patient's femur 5 at a predetermined position relative to the longitudinal axis 42 of the femur 5, so as to facilitate the cutting of prosthetic joint locating faces in the lower extremity 4 of the femur 5, thereby to provide for the fitment of the prosthetic joint thereto in a predetermined orientation which approximates the anatomical normality of the patient's joint.
More particularly, in use, by mounting the valgus block and stylus assembly 15 to the projecting end portion of the partially inserted reference pin 40 the surgeon is able to adjust the positioning of the bone cutting guide 13 of the bone cutting guide assembly 12 such that the distal femoral cutting block 14 of the bone cutting guide 13 is located at a predetermined position, so as to guide the cutting of joint locating faces into the lower extremity 4 of the femur 5 which allow for the fitment of the prosthetic joint to the femur and furthermore for the correct orientation of the prosthetic joint with respect to the mechanical axis of the femur when the prosthetic joint is fitted thereto.
In use, a surgeon will select a valgus block 16 from a library of valgus blocks. Each valgus block is configured to compensate for a different so-called "valgus angle" of the patient, to produce a desired orientation of cuts into the patient's distal femur. In use, the selected valgus block is releasably mounted to the projecting end portion of the reference pin 40 by receiving the projecting end portion of the reference pin 40 within the central angled aperture 20 of the valgus block 16 and sliding the valgus block 16 down the reference pin 40 to the position shown in Figure 5A of the drawings. The stylus 17 is then releasably mounted to the valgus block 16 by inserting the posts 26 projecting from the first carrying arm 22 of the stylus 17 through the pair of apertures 19 defined through the valgus block 16 and locking the lock nuts 21 such that each lock nut 21 clamps onto a different one of the pair of posts 26 for releasably mounting the stylus 17 and the valgus block 16 to one another. The bone cutting guide 13 is then releasably mounted to the valgus block and stylus assembly 15, as shown in Figure 5A of the drawings, so as to locate the distal femoral cutting block 14 relative to the lower extremity 4 of the femur 5. More particularly, as best illustrated in Figure 5B of the drawings, the second clamping arm 24 of the stylus 17 is slidingly received within a dove-tail type recess 9 defined on the inner side of the bone cutting guide 13, as best illustrated in Figure 5B of the drawings. The bone cutting guide 13 is then fixedly secured to the femur by means of bone mounting pins (not shown). After the bone cutting guide 13 is fixedly secured to the femur 5, the reference pin 40, and the valgus block and stylus assembly 15 are then removed from the femur, leaving only the bone cutting guide 13 mounted to the patient's femur 5. The distal femoral cutting block 14 of the bone cutting guide 13 then guides surgical cutters used to cut a distal cut into the patient's distal femur to provide a first one of a series of joint locating faces cut into the femur, to provide for the fitment of the prosthetic joint thereto in a pre-determined configuration. For example, if a surgeon selects a 6° valgus block, a cut made on the anterior distal femur will be offset by 6° with reference to the longitudinal axis 42 of the patient's femur 5. This cut will also be normal to a mechanical axis of the patient's femur. The distal cut thus defines the distal joint locating face which is then used to orientate other cutting guides (not shown), for guiding the cutting of a series of second and subsequent prosthetic joint locating faces which are cut into the lower extremity of the patient's femur.
The reference pin 40 has an overall length of between 100 mm to 120 mm. The reference pin 40 has a penetrating formation which is configured to be inserted into the patient's bone. The penetrating formation has a length of between 10 mm to 40 mm and defines an anchoring formation in the form of a helical screw formation which has a core diameter d2 of approximately 3.5 mm and a helical screw diameter di of approximately 8 mm.
As such, it will be appreciated that the penetrating formation of the reference pin 40 is particularly shorter, thinner and less invasive than the prior art femoral intramedullary rod described hereinabove. It will accordingly be appreciated that, in use, the insertion of the penetrating formation of the reference pin 40 into the lower extremity 4 of the femur 5 is thus less invasive than is the insertion of the femoral intramedullary rod into the medullary canal of the patient's femur. More specifically, because the penetrating formation of the reference pin 40 has a length of between 10mm to 40mm the penetrating formation of the reference pin 40 particularly does not penetrate into the medullary canal of the femur, as the penetrating formation is too short to reach the medullary canal of the femur when the penetrating formation of the reference pin is inserted into the patient's bone.
More specifically, the applicant envisages that the penetrating formation of the reference pin 40 will alleviate the risk of damage and possible infection caused to the patient's bone during insertion of the intramedullary rod into the medullary canal of the patient's bone. This is particularly the case when the risk of damage and possible infection is increased in the case of elderly patient's having fragile and brittle bones and who are generally more susceptible to damage and to the risk of infection. It will also be appreciated that insertion of the prior art intramedullary rod, which has a diameter of approximately 8 mm, will leave an approximately 8 mm hole in the femur which extends into the medullary canal and exposes the medullary canal to an external environment. By comparison, it will be appreciated that the penetrating formation of the reference pin 40 only leaves a much smaller hole equivalent to the size of the core diameter d2 of approximately 3.5 mm, and particularly does not reach the medullary canal.
It will also be appreciated that the helical screw formation of the penetrating formation of the reference pin 40 enables the length of the penetrating formation to be of a relatively short length because the helical thread will provide for the anchoring of the reference pin 40 to the bone and, as such, it is not necessary for the penetrating formation of the reference pin 40 to extend deeply into the bone in order to anchor the reference pin 40 securely to the bone.
It will thus also be appreciated that whereas the prior art intramedullary rod described hereinabove is inserted into and aligned with the medullary canal of the patient so as to approximate the longitudinal axis of the joint bone, the reference pin 40 of the present invention is particularly accurately aligned with respect to the actual longitudinal axis 42 of the femur 5 which is determined from the anatomical data of the position and orientation of the longitudinal axis of the femur. As such, the positioning guide 10 provides a more accurate and less invasive means of positioning the bone cutting guide assembly 12 relative to the lower extremity 4 of the femur 5.
The applicant also envisages that in another embodiment (not shown) the guide passage may be configured for guiding the partial insertion of a reference pin into the femur along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the femur.
With reference to Figure 6 of the drawings, another example of a positioning guide in accordance with a first aspect of the invention, in the form of a tibial positioning guide, is designated generally by the reference numeral 100. The tibial positioning guide 100 of Figure 6 is similar to the femoral positioning guide 10 of Figures 1 to 3 of the drawings, and as such, features of the tibial positioning guide 100 which are the same and/or similar to features of the femoral positioning guide 10 are indicated by the same and/or similar reference numerals. What is stated above with respect to the femoral positioning guide 10 applies generally to the tibial positioning guide 100.
The tibial positioning guide 100 is configured for positioning a bone cutting guide assembly (not shown) relative to an upper extremity 104 of a tibia 105 of a patient's knee joint during a joint replacement surgical procedure.
The tibial positioning guide 100 comprises a bone mounting structure 128 including a moulding 130 comprising a pair of moulding parts 130.1 , 130.2, a pin-guiding formation in the form of a guide formation 132 and a pair of arms 1 16 for connecting the guide formation 132 and the moulding parts 130.1 , 130.2 to one another in a predetermined orientation and spacial relationship.
The moulding parts 130.1 , 130.2 define complementary locating formations 134 on inner sides of the moulding parts 130.1 , 130, 2 which correspond to anatomical formations 136 defined on side regions of the tibia 105 and on end regions of the upper extremity 104 of the tibia 105, respectively. The locating formations 134 provide for secure fitment of the bone mounting structure 128 to the tibia 105 in a specific position. More particularly, the profile of the locating formations 134 of the moulding parts 130.1 , 130.2 conform to the profile of corresponding anatomical formations of the tibia 105.
The guide formation 132 defines a cylindrical guide passage 138 for guiding insertion of a reference pin 140 into the tibia 105 when the bone mounting structure 128 of the tibial positioning guide 100 is fitted to the tibia 105, as shown in Figure 6 of the drawings.
The guide formation 132 has a predetermined orientation and spacial relationship relative to the moulding 130 and is integrally formed therewith. More specifically, the orientation and spacial relationship of the guide formation relative to the moulding, is obtained from the anatomical data obtained from a radiographic scan of the joint bone from which scan the position and orientation of the longitudinal axis of the joint bone is accurately ascertained. After fitment of the moulding parts 130.1 , 130.2 of the bone mounting structure 128 to the tibia 105, in the position shown in Figure 6 of the drawings, such that the complementary locating formations 134 of the moulding parts 130.1 , 130.2 are aligned with the corresponding anatomical formations 136 of the tibia 105, the guide formation 132 guides insertion of the reference pin 140 along an axis accurately aligned with respect to the longitudinal axis 142 of the tibia 105.
In use, the tibial positioning guide 100 provides for the accurate location of the reference pin 140 relative to the tibia 105 such that the reference pin 140 is accurately aligned with respect to a longitudinal axis 142 of the tibia 105.
It will thus be appreciated that the reference pin 140 provides an attachment to which guide mounting means of a tibial bone cutting guide assembly (not shown) can be releasably mounted, for releasably mounting a cutting guide of the tibial bone cutting guide assembly to the patient's tibia 105.
With reference to Figures 3 of the drawings, the invention extends to a bone cutting guide system in accordance with a second aspect of the invention, in the form of a femoral bone cutting guide system, is designated generally by the reference numeral 200.
The femoral bone cutting guide system 200 is configured for guiding the cutting of at least one prosthetic joint locating face in the lower extremity 4 of the patient's femur 5 to allow for the secure fitment of a prosthetic joint (not shown) to the femur in a predetermined orientation which approximates the anatomical normality of the patient's knee joint.
The femoral bone cutting guide system 200 includes the reference pin 40; the bone cutting guide assembly 12 and the femoral positioning guide 10 described hereinabove in accordance with the first aspect of the invention. It will be appreciated that the exact configuration of the femoral positioning guide 10, the tibial positioning guide 100 and the femoral bone cutting guide system 200, in accordance with the invention may vary greatly while still incorporating the essential features of the invention as described hereinabove.

Claims

CLAIMS:
1 . A positioning guide for positioning a bone cutting guide assembly relative to a patient's joint bone during a joint replacement surgical procedure for guiding the cutting of at least one prosthetic joint locating face in an end region of a joint bone of a human patient to allow for the secure fitment of a prosthetic joint to the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint, the bone cutting guide assembly including a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting said prosthetic joint locating face in said end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially insertable into a medullary canal of a patient's joint bone such that a projecting end thereof projects from the bone, the bone cutting guide being releasably mountable to the guide mounting thereby to mount the bone cutting guide relative to the patient's bone, the positioning guide comprising: a bone mounting structure including:
(a) a moulding which is constructed from anatomical data obtained of the end region of the joint bone so as to define locating formations which correspond to anatomical formations of the end region of the joint bone, thereby to provide for the secure fitment of the bone mounting structure to the end region of the joint bone wherein the profile of the complementary locating formations of the moulding conforms to the profile of the corresponding anatomical formations of the end region of the joint bone; and
(b) a pin-guiding formation which defines a guide passage having a predetermined orientation and spatial relationship relative to the moulding which is obtained from anatomical data of the position and orientation of the longitudinal axis of the joint bone for guiding the partial insertion of a reference pin into the joint bone along an axis which, after secure fitment of the moulding to the end region of the joint bone, has a predetermined spatial relationship with respect to at least one of a mechanical axis of the joint bone and a longitudinal axis of the joint bone, so as to provide for releasable mounting of the guide mounting means of the bone cutting guide assembly to a projecting end portion of the partially inserted reference pin, in use, thereby to facilitate accurate location of the bone cutting guide relative to the joint bone, for guiding the cutting of the prosthetic joint locating face in the joint bone.
2. A positioning guide as claimed in Claim 1 , wherein the guide passage is configured for guiding said partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the longitudinal axis of the joint bone.
3. A positioning guide as claimed in Claim 1 , wherein the guide passage is configured for guiding said partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the joint bone.
4. A bone cutting guide system for use in a joint replacement surgical procedure for guiding the cutting of at least one prosthetic joint locating face in an end region of a joint bone of a human patient to allow for the secure fitment of a prosthetic joint to the joint bone in a predetermined orientation which approximates the anatomical normality of the patient's joint, the bone cutting guide system including: a reference pin which is configured to be at least partially inserted into an end region of a patient's joint bone; a bone cutting guide assembly including a bone cutting guide having at least one cutter guide formation for guiding a cutter for cutting said prosthetic joint locating face in said end region of the joint bone; and guide mounting means which is releasably mountable to a projecting end portion of an elongate intramedullary rod which is partially insertable into a medullary canal of a patient's joint bone such that a projecting end thereof projects from the bone, the bone cutting guide being releasably mountable to the guide mounting means thereby to releasably mount the bone cutting guide relative to the patient's bone; and a positioning guide comprising a bone mounting structure including :
(a) a moulding which is constructed from anatomical data obtained of the end region of the joint bone so as to define locating formations which correspond to anatomical formations of the end region of the joint bone, thereby to provide for the secure fitment of the bone mounting structure to the end region of the joint bone wherein the profile of the complementary locating formations of the moulding conforms to the profile of the corresponding anatomical formations of the end region of the joint bone; and
(b) a pin-guiding formation which defines a guide passage having a predetermined orientation and spatial relationship relative to the moulding which is obtained from anatomical data of the position and orientation of the longitudinal axis of the joint bone for guiding the partial insertion of the reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, has a predetermined spatial relationship with respect to at least one of a mechanical axis of the joint bone and a longitudinal axis of the joint bone, so as to provide for the releasable mounting of the guide mounting means of the bone cutting guide assembly to a projecting end portion of the partially inserted reference pin, in use, thereby to facilitate accurate location of the bone cutting guide relative to the joint bone, for guiding the cutting of the prosthetic joint locating face in the joint bone.
5. A bone cutting guide system as claimed in Claim 4, wherein the guide passage is configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the longitudinal axis of the joint bone.
6. A bone cutting guide system as claimed in Claim 4, wherein the guide passage is configured for guiding the partial insertion of a reference pin into the joint bone along an axis which, after fitment of the moulding to the end region of the joint bone, is aligned with the mechanical axis of the joint bone.
7. A bone cutting guide system as claimed in any one of Claims 4 to 6, wherein the reference pin has a penetrating formation which is configured to be inserted into the patient's bone.
8. A bone cutting guide system as claimed in Claim 7, wherein the penetrating formation of the reference pin has a length dimension which is preselected to ensure that the penetrating formation does not reach the medullary canal of the patient's bone when the penetrating formation is inserted into the end region of the patient's bone.
9. A bone cutting guide system as claimed in Claim 8, wherein the penetrating formation of the reference pin has a length dimension of between 10 mm and 40 mm.
10. A bone cutting guide as claimed in any one of claims 7 to 9, wherein the penetrating formation has at least one anchoring formation for anchoring the reference pin to the patient's bone.
1 1 . A bone cutting guide system as claimed in Claim 10, wherein the anchoring formation is in the form of a helical screw formation which is configured to be screwed into the patient's bone for anchoring the reference pin to the bone.
12. A bone cutting guide system as claimed in Claim 1 1 , wherein the penetrating formation is formed by a centrally disposed cylindrical rod-like core which has the helical screw formation projecting radially outwardly therefrom.
13. A bone cutting guide system as claimed in Claim 12, wherein a diameter of the cylindrical rod-like core is less than half of a diameter of the helical screw formation.
14. A bone cutting guide system as claimed in Claim 13, wherein the diameter of the cylindrical rod-like core is approximately 3.5 mm.
15. A bone cutting guide system as claimed in Claim 13 or Claim 14, wherein the diameter of the helical screw formation is approximately 8 mm.
PCT/IB2013/052070 2012-03-16 2013-03-15 A positioning guide for positioning a bone cutting guide assembly and a bone cutting guide system WO2013136303A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ZA201201993 2012-03-16
ZA2012/1993 2012-03-16

Publications (1)

Publication Number Publication Date
WO2013136303A1 true WO2013136303A1 (en) 2013-09-19

Family

ID=48428528

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2013/052070 WO2013136303A1 (en) 2012-03-16 2013-03-15 A positioning guide for positioning a bone cutting guide assembly and a bone cutting guide system

Country Status (1)

Country Link
WO (1) WO2013136303A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150245879A1 (en) * 2014-02-28 2015-09-03 Constantinos Nikou System and methods for positioning bone cut guide
US9855106B2 (en) 2014-02-28 2018-01-02 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
FR3119750A1 (en) * 2021-02-15 2022-08-19 Ngambo Patrick NGOUNOU Cutting guide device for cutting the distal end of the femur bone prior to fitting a total knee prosthesis, and method of manufacturing at least part of said device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5417694A (en) 1993-11-08 1995-05-23 Smith & Nephew Richards Inc. Distal femoral cutting guide apparatus with anterior or posterior referencing for use in knee joint replacement surgery
US20050234461A1 (en) * 2001-05-25 2005-10-20 Burdulis Albert G Jr Surgical tools facilitating increased accuracy, speed and simplicity in performing joint arthroplasty
GB2447702A (en) * 2007-03-23 2008-09-24 Univ Leeds Surgical bone cutting template
US20110245835A1 (en) * 2007-06-25 2011-10-06 Depuy Orthopadie Gmbh Surgical Instrument
WO2011156748A2 (en) * 2010-06-11 2011-12-15 Smith & Nephew, Inc. Systems and methods utilizing patient-matched instruments

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5417694A (en) 1993-11-08 1995-05-23 Smith & Nephew Richards Inc. Distal femoral cutting guide apparatus with anterior or posterior referencing for use in knee joint replacement surgery
US20050234461A1 (en) * 2001-05-25 2005-10-20 Burdulis Albert G Jr Surgical tools facilitating increased accuracy, speed and simplicity in performing joint arthroplasty
GB2447702A (en) * 2007-03-23 2008-09-24 Univ Leeds Surgical bone cutting template
US20110245835A1 (en) * 2007-06-25 2011-10-06 Depuy Orthopadie Gmbh Surgical Instrument
WO2011156748A2 (en) * 2010-06-11 2011-12-15 Smith & Nephew, Inc. Systems and methods utilizing patient-matched instruments

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150245879A1 (en) * 2014-02-28 2015-09-03 Constantinos Nikou System and methods for positioning bone cut guide
WO2015131138A1 (en) 2014-02-28 2015-09-03 Blue Belt Technolgies, Inc. System and methods for positioning bone cut guide
US9855106B2 (en) 2014-02-28 2018-01-02 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US10105152B2 (en) 2014-02-28 2018-10-23 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US20180303554A1 (en) * 2014-02-28 2018-10-25 Smith & Nephew, Inc. System and methods for positioning bone cut guide
US10130428B2 (en) 2014-02-28 2018-11-20 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US10251706B2 (en) 2014-02-28 2019-04-09 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
AU2015222741B2 (en) * 2014-02-28 2019-11-07 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US10667865B2 (en) 2014-02-28 2020-06-02 Blue Belt Technologies, Inc. Systems and methods for patient-based computer aided surgical procedures
US10898269B2 (en) 2014-02-28 2021-01-26 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US10912613B2 (en) 2014-02-28 2021-02-09 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US10912614B2 (en) 2014-02-28 2021-02-09 Blue Belt Technologies, Inc. Systems and methods for patient-based computer aided surgical procedures
US10918440B2 (en) 2014-02-28 2021-02-16 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US10925673B2 (en) 2014-02-28 2021-02-23 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US10939961B2 (en) 2014-02-28 2021-03-09 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
US11020185B2 (en) 2014-02-28 2021-06-01 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
AU2020200777B2 (en) * 2014-02-28 2022-03-31 Blue Belt Technologies, Inc. System and methods for positioning bone cut guide
FR3119750A1 (en) * 2021-02-15 2022-08-19 Ngambo Patrick NGOUNOU Cutting guide device for cutting the distal end of the femur bone prior to fitting a total knee prosthesis, and method of manufacturing at least part of said device

Similar Documents

Publication Publication Date Title
US9974550B2 (en) Tibial cutting block
EP2445419B1 (en) A positioning guide and a femur bone cutting guide system
US9962209B2 (en) Devices and method of achieving bone fusion
US9456833B2 (en) Patient-specific osteotomy devices and methods
EP3023068B1 (en) Bone plates, plate alignment systems, and methods of use
EP2967697B1 (en) Ankle replacement system
US9795392B2 (en) Surgical instrumentation set and surgical technique
US20220280167A1 (en) Surgical assembly, stabilisation plate and methods
US10463379B2 (en) Customized surgical cutting guide for total knee replacement and method for making thereof
HU219014B (en) Device for mechanical alignment of bone screws in a medullary nail
AU2016206883B2 (en) Washer plate
WO2015003284A2 (en) Surgical perforation guide
WO2014020562A1 (en) A surgical tool guide
CN110650694B (en) Offset guide
US10682195B2 (en) Surgical guide
US8679131B2 (en) Bone preparation reference guide
JP2022153485A (en) Gap gage and unit capable of checking flexion gap prior to cutting of posterior femur
WO2013136303A1 (en) A positioning guide for positioning a bone cutting guide assembly and a bone cutting guide system
WO2013136302A1 (en) A bone cutting guide and a bone cutting guide system
KR20160067858A (en) A surgical jig

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13722069

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 13722069

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 13722069

Country of ref document: EP

Kind code of ref document: A1

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 16/07/2015)

122 Ep: pct application non-entry in european phase

Ref document number: 13722069

Country of ref document: EP

Kind code of ref document: A1