The stiff total knee arthroplasty

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1 MANAGEMENT FACTORIALS IN TKA The stiff total knee arthroplasty CAUSES AND CURES K. G. Vince From Whangarei Hospital, Kamo, New Zealand Seven stiff total knee arthroplasties are presented to illustrate the roles of: 1) manipulation under general anesthesia; 2) multiple concurrent diagnoses in addition to stiffness; 3) extraarticular pathology; 4) pain as part of the stiffness triad (pain and limits to flexion or extension); 5) component internal rotation; 6) multifactorial etiology; and 7) surgical exposure in this challenging clinical problem. K. G. Vince, MD, FRCS(C), Consultant Orthopedic Surgeon Whangarei Hospital, Northland District Health Board, 118 Crane Rd. RD 1, Kamo, 0185, New Zealand Correspondence should be sent to K. G. Vince British Editorial Society of Bone and Joint Surgery doi: / x.94b $2.00 J Bone Joint Surg Br 2012;94-B, Supple A: Technical skill is mastery of complexity, but creativity is mastery of simplicity The Cambridge mathematician and topologist Christopher Zeeman, known for the term arthrofibrosis and his contributions to catastrophe theory said technical skill is mastery of complexity while creativity is mastery of simplicity. Successful revision of the stiff total knee arthoplasty (TKA) will require the greatest technical skill and the ability to reduce complex failure (catastrophe) to a complete roster of simple problems: technical skill and creativity. These are seven concise case presentations, each one illustrating a facet of the complex problems that come under the heading of the stiff TKA. Knee motion combined with stability epitomises the successful arthroplasty surgery. Satisfactory surgery requires a stable joint that extends fully with strength, and bends comfortably to a degree that permits normal activities. Ultimately, the limit of flexion in any TKA will be how far the quadriceps muscle can stretch. Accordingly, pre-op flexion is the major, but not the only, determinant of postoperative flexion. 1 When surgeons describe an arthroplasty as stiff they mean that either extension or flexion fails to reach a certain expected point; usually full extension and some arbitrary amount of flexion, usually in excess of 90. By contrast, patients often use the word stiff to describe the feeling of moving the joint. For example two doors may open and close fully. The one with rusted hinges requires greater force to reach the same point. Accordingly, a patient with full extension and flexion to 110, may yet describe their TKA as stiff if motion is difficult. Every complex mechanism requires all subsystems to function, for overall success. It is dangerous to accept stiffness in a TKA without analysis. This implies that the stiff TKA is one entity and implying further that everyone understands exactly what it is. Worse still is the use of arthrofibrosis, sounding as it does erudite and insightful, as a synonym for stiffness. Arthrofibrosis implies that stiffness results from the patient s tendency to form scar tissue, and not in the arthroplasty. Obviously, if a surgeon believes that arthrofibrosis is the cause of stiffness, (as it may be in a minority of cases) then revision surgery should not be contemplated. Won t that same unnatural tendency to form scar tissue simply make the revision stiff as well? Case one: manipulation under general anaesthetic A 68-year-old female presented for right TKA. She was pleased with her left TKA but had required a manipulation under general anaesthesia (MUGA) to achieve functional flexion. (Fig. 1a) The indications for both arthroplasties were painful osteoarthritis, in knees with reasonable flexion prior to surgery. The right TKA was performed uneventfully (Figs. 1b, 1c and 1d). The patellae tracked centrally, indicating correct rotational position of all components. She progressed slowly after surgery and a MUGA was performed eventually resulting in 115 of flexion. This case was straightforward: a patient, unwilling or unable to participate in effective physical therapy following TKA who benefited from MUGA. Having performed the surgery, I was confident that the TKA was mechanically capable of superior motion and proceeded with MUGA. Nascent scars stretched easily while the patient was anaesthetised, and recovery returned to schedule. VOL. 94-B, No. 11, NOVEMBER

2 104 K. G. VINCE Fig. 1 Figure 1a antero-posterior (AP) standing radiographs of the arthritic right knee (viewed on our left) and the successful left TKA. Motion on the left was satisfactory only after a MUGA (manipulation under general anesthesia). Figure 1b AP standing radiograph of right TKA. Figure 1c merchant patellofemoral radiograph showing central tracking of the patella and indicating that rotational position of the tibial and femoral components is satisfactory. Figure 1d lateral radiograph of the right TKA with the limb slightly rotated, so that the posterior condyles are seen separately and the fixation lugs do not lineup correctly. This may give the illusion of a larger than ideal femoral component. Tibial slope is satisfactory. Knee motion was 0 to 75 before and 0 to 115 after manipulation under general anesthesia. Figure 1e diagram showing that if the increase in the AP dimension of the femoral condyles by more than 12% was a critically independent variable leading to the need for MUGA. Reprinted from Daluga D, Lombardi AV Jr, Mallory TH, Vaughn BK. Knee manipulation following total knee arthroplasty: analysis of prognostic variables. J Arthroplasty 1991;6: , with permission from Elsevier. Daluga 2 and colleagues remind us that the recommendation for MUGA is not always straightforward. They compared 60 TKAs that required MUGA with 41 that achieved motion routinely. They found that an AP (antero-posterior) dimension of femoral prosthesis more than 12% greater than the patient s femur was a critically independent variable that predisposed to manipulation, i.e. to stiffness. An oversized femoral component usually makes the TKA tighter in flexion and therefore stiff. Of all the TKA s that undergo MUGA, some will be perfectly balanced and benefit, while others may have some mechanical impediment to motion that MUGA cannot overcome. The first lesson to learn from this case is that a TKA has either been performed adequately in all respects and so can permit motion up to the limit imposed by quadriceps flexibility or there is some inherent feature that mechanically limits motion. The second lesson to learn is that arthrofibrosis may be one cause of stiffness, but the two terms are not synonymous. If a TKA is stiff there will be scar. It doesn t mean that the scar caused the stiffness. Case two: systematic and comprehensive diagnosis Stiffness may result from more serious problems, in which case manipulation alone will fail. In this case a 74-year-old male presented with a stiff TKA. Radiographs indicated a prior tibial tubercle transfer, as treatment for a dislocating patella (Fig 2). Our approach to every problem TKA is 1) systematic and 2) comprehensive. 3,4 Systematic means that the same disciplined evaluation should be followed for each case. We use a worksheet that lists the eight indications for revision on the left, and on the right (Fig 2d), the necessary data that must be collected to confirm the diagnosis and plan corrective surgery. Infection tops the list, as it must be considered in every case. Simple diagnoses follow, some of which can be identified even over the telephone. The most CCJR SUPPLEMENT TO THE JOURNAL OF BONE AND JOINT SURGERY

3 THE STIFF TOTAL KNEE ARTHROPLASTY 105 Figure 2a radiographs of a 74 year old male patient who presented with a stiff primary TKA, where two screws are evidence of a tibial tubercle transfer to treat a patellar dislocation not long after the TKA had been performed. Figure 2b lateral radiograph of a stiff TKA demonstrating an oblique image of the patella, normal patellar height, good tibial component slope and an appropriate size of femoral component. The tubercle osteotomy is apparent. This is maximum flexion, approximately 35. Figure 2c merchant patella-femoral radiograph demonstrating oblique position of a re-surfaced patella, suggesting that it wants to dislocate, but has been strapped into the trochlear groove by the tubercle osteotomy. Figure 2d problem TKA worksheet listing the reasonable indications for revision TKA on the left column (1 to 8) and # 9: no diagnosis, where further evaluation is mandatory and surgery should be avoided. Figure 2e lateral radiograph of a non-articulating, antibiotic impregnated, methyl-methacrylate spacer as part of a two-stage re-implantation protocol for infection. Figure 2f AP radiograph of non-articulating spacer, with removal of all foreign material, including screws. Figure 2g AP radiograph of reimplanted TKA: the second stage after control of infection. Cement fixation has been employed with fixation augmented by diaphyseal engaging press-fit stems; straight on the femur and with an offset on the tibia. Figure 2h lateral radiograph of re-implanted TKA. Figure 2i partial full length radiograph showing press fit stems engaged in the diaphysess of tibia and femur with restoration of neutral mechanical axis. Figure 2j centrally tracking patella in an arthroplasty without infection, significant pain relief and flexion improved to 90. Fig. 2 commonly made diagnosis loosening is held in reserve to force us to consider all others first, and not jump to conclusions. Comprehensive means that we consider every possible diagnosis, even having identified one compelling problem in a TKA. This patient presented with stiffness. It would be foolhardy to leave the assessment at that point. A systematic approach required that infection be considered first and indeed ESR and CRP were elevated, indicating the importance of an aspiration of synovial fluid. 5 White cell count, differential and culture all confirmed the diagnosis of sepsis. Our comprehensive approach forced us to consider patellar tracking problems and their ineluctable association with internal rotation of tibia and or femoral components. 6 The final assessment was an infected TKA, with a failed tibial tubercle transfer for patellar dislocation because the basic problem was internal rotation of tibial and femoral components. Incidentally, because of pain, scarring and patellar dislocation, the TKA was stiff. The patient was treated with a two-stage re-implantation protocol for infection 7-10 (Figs 2e & 2f). The re-implantation was performed with careful attention to rotational position of the tibial and femoral components, yielding a centrally tracking patellar with increased comfort and flexion (Figs 2g to 2j). This case teaches us that poor motion may be the result of another more fundamental problem with the arthroplasty VOL. 94-B, No. 11, NOVEMBER 2012

4 106 K. G. VINCE Fig. 3a Fig. 3b Fig. 3c Figure 3a AP radiograph of failed, loose, stiff TKA in a super obese patient. Serial MUGA s eventually lead to aseptic loosening with a peri-prosthetic fracture, seen here. Figure 3b lateral radiograph showing proximal tibial fracture, that one can visualise resulting from forced flexion during a MUGA. The femoral component has been implanted in an undesirably flexed position that encroaches on the flexion gap, making the correct sized implant function like one that is too large. Figure 3c AP radiograph of the pelvis demonstrating a severely arthritic hip (arrow) ipsilateral to the painful stiff TKA. and that no matter what else is wrong with the arthroplasty it may also be infected. Each TKA must be evaluated with a disciplined system and completely. Case three: extra-articular problems This 56 year old female patient was referred to our unit with a painful, stiff TKA. Her body mass index placed her in the super obese category. 11 Several MUGA s had been performed elsewhere. The last one resulted in a tibial fracture and loose component (Figs 3a & 3b). A systematic and comprehensive evaluation yielded a normal ESR and CRP, with low white cell count and differential in aspirated synovial fluid. Cultures of the fluid were negative, effectively eliminating infection as a cause of the failure. 12 Radiographs of the pelvis, which we perform routinely prior to revision of the stiff TKA revealed extensive hip arthropathy (Fig.3c). That knee symptoms may arise from hip pathology has been understood for many years, and not just by orthopedic surgeons. 13,14 Nonetheless, the diagnosis can be missed, perhaps because the patient is difficult to assess. The surgeons in this case were presumably so focused on stiffness, which they may have attributed to the obvious obesity that they neglected to fully evaluate the patient. While there are many demands on a clinician s time, this diagnosis cannot be missed. This stiff TKA was interpreted as a nothing more complicated than a condition requiring manipulation. No aetiology was considered, and causes outside the knee joint were overlooked. This case reminds us that stiffness can result from pain and that pain may originate outside of the knee joint. Case four: pain A 42-year-old woman presented with pain and stiffness in a TKA that had been performed for premature osteoarthritis in association with previous athletic injuries. She had wanted to remain reasonably active, but the results of surgery were disappointing (Fig 4). The TKA had a fixed flexion deformity of 15 and further flexion to 95, which many surgeons might not consider stiff. She had difficulty bending the knee and it was painful. There was no evidence of infection 12 and neither radiographs of the pelvis and lumbo-sacral spine, or a technetium bone scan, could locate a cause outside the knee. No findings other than pain indicated chronic regional pain syndrome. Critical evaluation of the radiographs revealed that the femoral component was of an appropriate size, but had been implanted posteriorly, making the flexion gap smaller and tighter. Effectively, this component functions like one of a larger size, replicating the effect noted above and reported by Daluga. 2 CT scanning revealed internal rotation positioning of the tibial component. The patient described pain and stiffness, but had 95 of flexion. Revision arthroplasty with careful component sizing according to soft-tissue tension, balancing of flexion and extension gaps 15 and rotational positioning of components was successful. The flexion contracture was eliminated but flexion increased only modestly from 95 to 110. The patient, however, was pleased with decreased pain. The stiff knee is usually a triad of flexion contracture, poor flexion and pain. We learned in 2001 from Barrack s elegant case-control study 16 comparing satisfied TKA patients with those suffering anterior knee pain, patients with otherwise unexplained anterior knee pain, had more internal rotation of femoral and in particular, tibial component position. If we identify the underlying problems in the TKA that presents primarily with stiffness and correct them, we stand a good chance of improving pain which is usually a very important part of the procedure. In other words, success may have more to do with reducing a feeling CCJR SUPPLEMENT TO THE JOURNAL OF BONE AND JOINT SURGERY

5 THE STIFF TOTAL KNEE ARTHROPLASTY 107 Fig. 4d Figure 4a Lateral radiograph of 42-year-old athletic mother of two boys who was profoundly disappointed with pain and stiffness after a TKA for arthritis following sports injuries and ligamentous reconstructions. The arrow indicates a notch in the anterior femur and posterior positioning of an appropriately sized femoral component, translating it into the flexion gap and functioning like an oversized component. Figure 4b AP radiograph showing subtle evidence of an internally rotated femoral component. A reasonably symmetric image of the tibia component appears only when the limb has been externally rotated by the radiology technician. This posture of the limb moves the proximal fibula (dotted outline) behind the tibia. Figure 4c the patella has been resurfaced, but cut asymmetrically sand seems to be tethered in the trochlear groove. Figure 4d the stiff TKA may manifest with one or all of the three constituents: 1) fixed flexion contracture, 2) poor flexion and 3) pain. Figure 4e - AP radiograph of the revision with one size smaller femoral component to accommodate a tighter, scarred soft tissue envelope. The tibial component appears symmetrically and the proximal fibula is not overlapped as much by the tibia indicating better rotational position of the component. Figure 4f - lateral radiograph showing the one size smaller femoral component and an anterior augment which brings the femoral component back into the desired position relative to the anterior femoral cortex. Figure 4g - long AP radiograph depicting diaphyseal press fit stems, using offset to manage anatomic asymmetry, fixation and alignment. Figure 4h the patella was not revised given the compromised residual bone stock. It is tracking centrally. The flexion contracture was eliminated, modest gains were made in flexion, but the patient was most grateful for pain reduction. Fig. 4 of painful tightness in a stiff TKA than with dramatic increases in the motion. Component rotational positioning is very important in understanding these arthroplasties. This case illustrates the triad of the stiff TKA: 1) flexion contracture; 2) poor flexion; and 3) pain. There are usually several mechanical features that predispose to stiffness and pain. While the total amount of flexion provided by revision may be modest, function improves with elimination of flexion contractures and patients are grateful if the knee is more comfortable and moves more freely, even within a limited arc. Case five: internal rotation A 41-year-old athletic male, developed arthritis after an anterior cruciate ligament reconstruction and underwent a TKA complicated by pain and very poor motion. The knee lacked 10 of extension and flexed to only 45. The pain was disabling. Good quality radiographs were impossible. When the prosthesis was imaged symmetrically, the limb is externally rotated (Figs 5a & 5b). When the limb was rotated correctly, the prosthesis could not be viewed well. The tibia was implanted in internal rotation and facilitated VOL. 94-B, No. 11, NOVEMBER 2012

6 108 K. G. VINCE Fig. 5d Fig. 5a Fig. 5b Fig. 5c Fig. 5e Fig. 5f Fig. 5g Fig. 5h Figure 5a radiograph of a painful stiff TKA cannot depict the limb and both components in a true AP rendering simultaneously, because of problems with the rotational position of the components. In this image the limb is reasonably well positioned, but the tibial (more prominent later tibial fixation flange) and femoral (more prominent lateral femoral condyle) components are internally rotated. Figure 5b the difficulty continues with the lateral radiograph which shows non-overlapping posterior femoral condyles as well as patella alta. Figure 5c lateral radiograph showing maximum flexion, with a femoral component that is probably slightly larger AP than the native bone. Figure 5d - patella is almost dislocated and certainly tracking poorly related to rotational positioning of tibial and femoral components. 19 Figure 5e CT scan of TKA according to a validated protocol to quantify rotational position of components, 6,17 showing the most proximal of three cuts on the tibia, establishing the tibial component angle, and illustrated by the line at 90 to the line passing through the posterior tibial condyles and projected to the upper left (arrow head). Its relation to the proximal tibia is established by two additional, more distal cuts. Figure 5f the most distal CT scan cut (third of three) through the level of the tibial tubercle. TCA is reproduced from figure 5e and the geometric center (see label and arrow at the right of the image) was established on a CT cut just below the component. A line has been drawn from the geometric center through the center of the tibial tubercle. Figure 5g figures 5e and 5f have been overlaid. It is clear the tibial component has been positioned internally, 42 to where it might have been aligned with the tubercle. Figure 5h - a patella has been added to figure 5g, showing how internal rotation of the tibial component delivers the patella, not to the central trochlear groove, but to the condyle with resultant maltracking and perhaps dislocation. by patella alta, the patella was subluxing and would probably dislocate if the knee was flexed further (Figs 5c & 5d). CT scanning is very useful in evaluating the stiff TKA and essential in this case. A validated protocol quantifies the rotational position of tibial and femoral components, with four cuts: one through the femoral epicondyles and three through the proximal tibia. 17 Tibial CT cuts image the component, the geometric center of the proximal tibia and the tibial tubercle. Given the asymmetry of the proximal tibia, upto 18 of internal rotation of the tibial component is permissible. 6 This patient had a tibial component oriented at 42 of internal rotation. (Figs 5e to 5g). By the time of revision arthroplasty, the knee had been so stiff over a prolonged period of time that the quadriceps had difficulty stretching. Gains in flexion were modest, correction of flexion contracture complete and the improvement in pain gratifying. Our experience with revision TKA demonstrated that one of the most consistent findings in the stiff TKA is internal rotation of the tibial component, 18 usually the result of limited exposure and a desire to maximise coverage of the asymmetric tibia. It is difficult to discuss the stiff TKA now without quantitative CT scan data on rotational positioning of the components. The lesson to learn from this case is that internal rotation predisposes to stiffness through maltracking. As the patient CCJR SUPPLEMENT TO THE JOURNAL OF BONE AND JOINT SURGERY

7 THE STIFF TOTAL KNEE ARTHROPLASTY 109 Fig. 6 Figure 6a AP radiograph of painful stiff TKA which in another era might have been labeled a mystery knee, because of no obvious explanation for pain. A further diagnosis of arthrofibrosis may have been added because of limited motion. Figure 6b lateral radiograph shows a thick polyethylene insert after a reasonable amount of tibial resection, plus neutral tibial slope, a relatively large femoral component and a thick patella construct. None of these feature by themselves might compromise motion, but together they add up to trouble. Figure 6c merchant patella-femoral view shows patellar maltracking, synonomous with internal rotation of tibial and femoral components. Figure 6d AP radiograph after complete revision arthroplasty with non-linked, constrained implants. A diaphyseal engaging press fit stem has been used on the femur for alignment and fixation, with a fully cemented stubby stem extension fully cement into the tibia because of relatively small stature. The stem extension has been modified intraoperatively to avoid endosteal impingement. Figure 6e patella is tracking centrally on the Merchant view indicating that rotational position of tibial and femoral components has been corrected. Figure 6f lateral radiographs shows satisfactory joint line height and patellar position. Figure 6g fish diagram illustrating the multifactorial nature of the stiff TKA. In particular, rotational positioning of components is of greater significance than has been appreciated in the past. flexes the knee and senses that the patella will dislocate, they become unwilling to flex further and never achieves functional flexion. 19 Case six: multi-factorial A 47-year-old female, four years after TKA presented with a stiff, painful TKA since surgery. There was a 5 fixed flexion contracture with flexion limited to 65. Pain was severe and constant. The modular tibial polyethylene insert was thick, probably chosen to balance the extension gap and eliminate recurvatum in a patient who had a relatively small flexion gap. The posterior slope for this prosthesis is recommended to duplicate normal anatomy, but here there was virtually no slope, which tends to tighten the knee in flexion. The lateral view showed a thick patellar construct and the merchant view showed that the patella was trying to dislocate, indicating problems with rotational alignment of the tibial and or femoral components (Figs 6a, 6b and 6c). Revision surgery that focuses on only one feature of this TKA will likely fail. The assessment must be analytical and detailed. Only a complete revision that can modify every variable in favor of greater motion over greater stability can be expected to succeed. Even with that, the elasticity of an extensor mechanism that has not been fully stretched in four years will ultimately limit motion. VOL. 94-B, No. 11, NOVEMBER 2012

8 110 K. G. VINCE Fig. 7e Fig. 7a Fig. 7b Fig. 7c Fig. 7d Fig. 7f Fig. 7g Fig. 7h Fig. 7i Fig. 7j Fig. 7k Fig. 7l Fig. 7m Fig. 7n Figure 7a - full-length AP radiographs showing well aligned but extremely stiff TKAs. Figure 7b - AP radiograph of the first TKA performed with correction of the extra-articular deformity above. Figure 7c - AP radiograph of second TKA also complicated by stiffness that patent has requested help with. Figure 7d - lateral radiograph of left TKA stiff but not for revision) with severe patella infer/baja. Figure 7e - attempted Merchant patella-femoral view impaired by patients inability to flex past 15. Figure 7f - lateral of stiff left TKA for revision. Slope and sizing are reasonable. It cannot be established whether the contracted patellar tendon contributes to or results from the stiffness. Figure 7g - in surgery, immediately prior to revision arthroplasty. Flexion limited to less than 40 with very hard end point. Figure 7h - extensive synovectomy, decreases thickness of scar and reveal supple tissue in the supra-patellar pouch. Figure 7i - scar on either side of the femur is released longitudinally, to re-establish the normal para-femoral gutters. This improves the excursion of the extensor mechanism. Figure 7j - thick wad of scar on the deep surface of the patellar tendon, which when removed, allows the tendon the stretch and twist more normally. The tendon is less likely to avulse from its insertion. Figure 7k a lateral patellar retinacular release is performed for exposure, not patellar tracking. It allows the entire soft tissue envelope to expand. Figure Fig. 7o 7l - long handled scissors are useful to divide scars halfway up the thigh that have stuck the deep extensor to the femur. Figure 7m - before any components are removed a gentle manipulation takes advantage of the Fig. 7p Fig. 7q releases that have been performed. Figure 7n - the quadriceps snip is useful and well known. 24 An alternate maneuver that can be performed first is the quadriceps split whereby the arthrotomy is extended up into the muscle fibers. If this is inadequate, the snip should follow. Figure 7o the patient under consideration, was still difficult to exposure after all of the above steps had been taken. Ultimately, if a conventional medial release is performed, of the proximal medial and postereromedisal sleeve, as in a a classic release to correct varus deformity, the tibial can be flexed and externally rotated, driving the tubercle laterally to safely dislocate the knee. This may necessitate a constrained implant, but the exposure is superb and the extensor is protected. Figure 7p post revision AP with non-linked constrained implant. Aggressive release of scar usually destabilises a knee like this so that constraint is necessary. Figure 7q later radiograph after revision showing press fit stem extensions, anterior augmentation to bring the (smaller sized) femoral component out of flexion and thus decreasing the size and tension in the flexion gap. Motion improved to about 75 of flexion The lesson to learn from this case is that stiffness complicating TKA is often a multi-factorial problem. Accordingly, complete revision arthroplasty is appropriate and lesser interventions are rarely successful. Although some of the first cases described above were used to illustrate specific single points, every one of them was revised with attention to all of the variables that we have covered. CCJR SUPPLEMENT TO THE JOURNAL OF BONE AND JOINT SURGERY

9 THE STIFF TOTAL KNEE ARTHROPLASTY 111 Case seven: surgical exposure A 67-year-old male presented with bilateral stiff TKAs with relatively little pain. His main complaint was that with only 35 of flexion bilaterally, should he fall to the ground, he would be unable to get up. He was involved in a road traffic accident that left him with solidly healed femur fractures and decreased flexion in knees that eventually developed arthritis. The arthroplasties performed on stiff knees, in turn, became even stiffer. The argument can be made that his knees would be limited by the quadriceps muscle stiffness even if revision was performed. The patient is adamant that he would like to proceed as the current situation is unmanageable. The surgical team feels that aggressive lysis of scar and revision to components that permit greater laxity in flexion, (i.e. smaller femoral component) combined with an assiduous physical therapy protocol may improve the situation. Even modest gains would be welcome (Fig. 7). Many surgeons might recommend a tibial tubercle osteotomy for exposure. I believe that approach is unnecessary in this situation, as well as limiting and risky for aggressive physical therapy. In addition, the tubercle osteotomy does not, in itself, liberate the patient and the knee from extensive scarring. Surgical access might be excellent, but once the procedure is complete and the tubercle fixed back to the tibia, the extensor is stiff. The patellar turn-down is outdated 20, the V-Y plasty misguided (lengthening the extensor mechanism often leaves the patient with a disabling lag even if it increases flexion) and the quadriceps snip is of limited effectiveness The surgical approach must include: synovectomy, reestablishment of the parafemoral gutters, quadriceps liberation from the scarring that adheres to the anterior femur, scar removal from around the patellar tendon and sometimes a lateral patellar retinacular release for exposure, not patellar tracking. Ultimately, release of the proximal medial capsule and deep collateral ligament permits safe external rotation of the tibia. This drives the tubercle laterally, dislocating the knee. Non-linked constrained implants are useful generally in cases like these and will splint or supplant the medial soft-tissue envelope after the exposure. This has long been my approach for revision arthroplasty and has evolved concurrently and been reported by others as the, Extensor Mechanism Tenolysis. 28 This case brings us full circle to stiffness that is primarily of soft-tissue origin, a case of arthrofibrosis. It poses specify and significant challenges in terms of surgical exposure. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.this paper is based on a study which was presented at the Winter 2011 Current Concepts in Joint Replacement meeting in Orlando, Florida, 7th 10th December. References 1. Schurman DJ, Matityahu A, Goodman SB, et al. Prediction of postoperative knee flexion in Insall-Burstein II total knee arthroplasty. Clin Orthop Relat Res 1998;353: Daluga D, Lombardi AV Jr, Mallory TH, Vaughn BK. Knee manipulation following total knee arthroplasty: analysis of prognostic variables. J Arthroplasty 1991;6: Vince K, Munro J. Revision Total Knee Replacement. In: Bulstrode C, Wilson- MacDonald J, Fairbank J, Briggs T and Eastman D, eds. Oxford text of knee surgery. Oxford: Oxford University Press, 2011, Vince K. Modes of failure in total knee arthroplasty. In: Lieberman JR, Berry DJ, Frederick MA, eds. Advanced reconstruction of the knee. Rosemont: American Academy of Orthopedic Surgeons, 2011: Della Valle C, Parvizi J, Bauer TW, et al. American Academy of Orthopaedic Surgeons clinical practice guideline on: the diagnosis of periprosthetic joint infections of the hip and knee. J Bone Joint Surg [Am] 2011;93-A: Berger RA, Crossett LS, Jacobs JJ, Rubash HE. Malrotation causing patellofemoral complications after total knee arthroplasty. Clin Orthop Relat Res 1998;356: Insall JN, Thompson FM, Brause BD. Two-stage reimplantation for the salvage of infected total knee arthroplasty. J Bone Joint Surg [Am] 1983;65-A: Windsor RE, Insall JN, Urs WK, Miller DV, Brause BD. Two-stage reimplantation for the salvage of total knee arthroplasty complicated by infection: further followup and refinement of indications. J Bone Joint Surg [Am] 1990;72-A: Mortazavi SM, Vegari D, Ho A, Zmistowski B, Parvizi J. Two-stage exchange arthroplasty for infected total knee arthroplasty: predictors of failure. Clin Orthop Relat Res 2011;469: Leone JM, Hanssen AD. Management of infection at the site of a total knee arthroplasty. Instr Course Lect 2006;55: Schwarzkopf R, Thompson SL, Adwar SJ, Liublinska V, Slover JD. Postoperative complication rates in the "super-obese" hip and knee arthroplasty population. J Arthroplasty 2012;27: Parvizi J, Della Valle CJ. AAOS Clinical Practice Guideline: diagnosis and treatment of periprosthetic joint infections of the hip and knee. J Am Acad Orthop Surg 2010;18: Dittrich RJ. Disability of the knee due to referred pain and related phenomena. J Am Geriatr Soc 1955;3: Flatman JG. Hip diseases with referred pain to the knee. JAMA 1975;234: Vince K, Bedard M. Implanting the revision total knee arthroplasty. In: Lotke PA, Lonner J, eds. Master techniques in orthopedic surgery. Baltimore: Lippincott, Williams and Wilkins; 2008; Barrack RL, Schrader T, Bertot AJ, Wolfe MW, Myers L. Component rotation and anterior knee pain after total knee arthroplasty. Clin Orthop Relat Res 2001;392: Jazrawi LM, Birdzell L, Kummer FJ, Di Cesare PE. The accuracy of computed tomography for determining femoral and tibial total knee arthroplasty component rotation. J Arthroplasty. 2000;15: Bédard M, Vince KG, Redfern J, Collen SR. Internal rotation of the tibial component is frequent in stiff total knee arthroplasty. Clin Orthop Relat Res 2011;469: Malo M, Vince KG. The unstable patella after total knee arthroplasty: etiology, prevention, and management. J Am Acad Orthop Surg 2003;11: Smith PN, Parker DA, Gelinas J, Rorabeck CH, Bourne RB. Radiographic changes in the patella following quadriceps turndown for revision total knee arthroplasty. J Arthroplasty 2004;19: Scott RD, Siliski JM. The use of a modified V-Y quadricepsplasty during total knee replacement to gain exposure and improve flexion in the ankylosed knee. Orthopedics 1985;8: Aglietti P, Buzzi R, D Andria S, Scrobe F. Quadricepsplasty with the V-Y incision in total knee arthroplasty. Ital J Orthop Traumatol 1991;17: Trousdale RT, Hanssen AD, Rand JA, Cahalan TD. V-Y quadricepsplasty in total knee arthroplasty. Clin Orthop Relat Res 1993;286: Garvin KL, Scuderi G, Insall JN. Evolution of the quadriceps snip. Clin Orthop Relat Res 1995;321: Barrack RI. Specialized surgical exposure for revision total knee: quadriceps snip and patellar turndown. Instr Course Lect 1999;48: Arsht SJ, Scuderi GR. The quadriceps snip for exposing the stiff knee. J Knee Surg 2003;16: Meek RM, Greidanus NV, McGraw RW, Masri BA. The extensile rectus snip exposure in revision of total knee arthroplasty. J Bone Joint Surg [Br] 2003;85- B: Sharkey PF, Homesley HD, Shastri S, et al. Results of revision total knee arthroplasty after exposure of the knee with extensor mechanism tenolysis. J Arthroplasty 2004;19: VOL. 94-B, No. 11, NOVEMBER 2012