Dealing with the Challenge of Revision Total Knee Arthroplasty

Total knee arthroplasty (TKA) is one of the most successful orthopaedic procedures, with high patient satisfaction and excellent clinical outcomes. As the incidence of primary TKA continues to increase without any signs of slowing, it is expected that revision TKA will follow suit. While improvements in TKA design and instrumentation have greatly reduced the number of revisions required for polyethylene wear and osteolysis, patients still commonly undergo revision TKA for mechanical issues, such as aseptic loosening and instability, followed by infection. Although the overall annual failure rate after primary TKA is low, the rate of revision TKA worldwide is increasing with an overall annual rate estimated to be between 9 and 12%.[1] [2] [3] While there are various estimates for the different reasons for failure, aseptic loosening and infection dominate the cause of failure. Polyethylene wear had been a major cause of failure a decade ago, but modern polyethylene manufacturing techniques have produced materials with reduced wear characteristics and improved longevity. Most studies report aseptic loosening as the most frequent cause of failure, but other causes are stiffness, instability, and postoperative pain. When looking at early failure within the first 2 years of the primary TKA, infection and instability are typically, but not exclusively, the most common, while late failures are more commonly mechanical wear and loosening.[4] [5]

Revision TKA needs to be approached in a methodical fashion with a preoperative plan and technical acumen. The mode of failure needs to be determined preoperatively with a thorough clinical history, review of prior records, and operative report, and physical examination. Radiographs and, at times, advanced imaging provide further insight into the reason for failure, as well as a template for the instrumentation and implants that will be needed for the revision surgery. Preoperative laboratory testing including serology and aspiration are necessary to determine aseptic versus septic failure, since the course of treatment will differ. Failure to determine the cause of failure may result in repeating the initial cause of failure and a poor outcome.

The diagnosis of periprosthetic joint infection (PJI) remains a challenge, because no single preoperative investigative study is completely reliable and there are various diagnostic criteria for PJI. American Academy of Orthopaedic Surgeons (AAOS) guidelines strongly recommend blood work including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and more recently D-dimer has been suggested as an investigative serology test.[6] Joint aspiration with synovial fluid leukocyte count and differential are useful adjuncts to the ESR and CRP in the preoperative workup for PJI. Synovial fluid biomarkers, such as α-defensin and leukocyte esterase, exhibit a high accuracy in diagnosing PJI, even when including patients with systemic inflammatory disease and those receiving antibiotic treatment. More recently, the introduction of the Musculoskeletal Infection Society (MSIS) criteria for PJI has demonstrated improvements in diagnostic confidence with a high level of sensitivity ([Fig. 1]).[7]

Fig. 1 MSIS (Musculoskeletal Infection Society) criteria for periprosthetic infection. CRP, C reactive protein; ESR, erythrocyte sedimentation rate; LE, leukocyte esterase; PMN, polymorphonuclear leukocyte; WBC, white blood cell count.

A well-planned surgical approach to revision TKA necessitates a thoughtful assessment of the potential problems that may be encountered, such as exposure and component removal. Adequate exposure is necessary for removal of the components, soft tissue balancing, management of the bone loss, and ultimately accurate placement of the final components. Extensile exposure by dissection of fibrotic scar tissue, clearing the medial and lateral femoral gutters, quadriceps snip, or tibial tubercle osteotomy, may be necessary to avoid injury to the extensor mechanism, especially the patella tendon attachment at the tibial tubercle. The challenge of removing well-fixed components is dependent on the type of implant and requires broad exposure of the prosthetic-bone interface. Care should be taken in removing the components as to not damage the underlying bone which is the foundation for the subsequent reimplantation.

Following component removal, bone defects are assessed and classified. The Anderson Orthopedic Research Institute classification is useful for guiding reconstruction of bone defects.[8] Reconstruction of the bone defects include cement, bone graft and metaphyseal filling sleeves, and trabecular metal cones.[9] Since in revision TKA, the epiphyseal bone may be inadequate for component fixation, the concept of zonal fixation has become popular with femoral and tibial metaphyseal cones or sleeves and diaphyseal stem extensions, either cemented or press-fit, to obtain secure fixation ([Fig. 2]).[10]

Fig. 2 (A) Revision TKA components with femoral and tibial augments, cones and stem; (B and C) AP and lateral radiograph of revision TKA demonstrating the three zones of fixation. AP, anteroposterior; TKA, total knee arthroplasty.

Revision TKA encompasses a wide variation in complexity, from the relatively straightforward revision with little or no bone loss to those with severely compromised bone stock and supporting soft tissue structures. In order for a revision TKA to be successful, bone defects need to be addressed as mentioned above and the supporting soft tissues structures need to be assessed to reestablish a stable construct with balanced flexion and extension gaps. Following established general surgical principles provide a methodical roadmap for the revision: (1) reestablish the tibial platform, as it is the foundation of the revision influencing both the flexion and extension gaps; (2) choose the correct sized femoral component to reestablish the posterior condylar offset that influences the flexion gap; and (3) then set the distal position of the femoral component which sets the extension gap and joint line.[11] The level of constraint in revision TKA is determined by the inherent stability of the knee and integrity of the collateral ligaments.[12] Bone loss with loose components or subsidence may cause pseudolaxity or instability. Appropriately addressing the bone defects will reestablish tension in the intact collateral ligaments and soft tissue envelope such that a posterior stabilized articulation may be adequate. If there is functional loss of the medial collateral ligament or lateral collateral ligament, or inability to balance the flexion and extension spaces, then a constrained condylar prosthesis or rotating hinge is necessary.

While there is a significant improvement in patient-reported outcome measures following revision TKA, it has been noted that patient satisfaction remains low.[13] This observation may be due to the fact that the outcome of revision TKA is difficult to quantify, because the results are dependent on the mode of failure.[1] Revisions for PJI have worse patient outcomes than aseptic revisions. The comparison is further complicated when considering a simple tibial polyethylene exchange versus a complex revision with a megaprothesis. Differences in outcomes are also impacted by the implant design, including posterior stabilized prostheses, constrained condylar knee implants, and hinged knees. While comparative studies do provide insight on the results of revision TKA, more information may be gleaned from joint registries as more data are recoded. Owing to the variability in outcomes, some have recommended that revision TKA to be performed in specialty centers where resources and specialists are more readily available.[14] This is a responsible consideration since the economic burden of revision TKA continues to rise.[15] Especially as hospitals try to manage reimbursement against the cost. This is particularly true for revision of septic knees where some of the major contributing factors to the cost include the preoperative investigation, prolonged hospital stays, and implants. Projected hospital costs for revision TKA may exceed $2 billion by 2030.[16]

Overall, the rate of revision TKA is low, but the number of primary TKA performed continues to rise annually due to the reported success of the procedure, increased life expectancy, and the burden of osteoarthritis, creating the potential for a substantial health care burden. Improvements in implant design and surgical technique have improved the longevity of primary TKA, while reducing the risk of PJI through patient optimization and countermeasures have become a priority. However, even with these initiatives, revision TKA will be inevitable. This fact necessitates a deliberate focus on patient risk adjustments, surgical training, and the economic impact to reduce the burden on the health care system and maximize patient outcomes.

Publication History

Received: 08 July 2021

Accepted: 13 July 2021

Article published online:
31 October 2021

• References

• 1 Bozic KJ, Kamath AF, Ong K. et al. Comparative epidemiology of revision arthroplasty: failed THA poses greater clinical and economic burdens than failed TKA. Clin Orthop Relat Res 2015; 473 (06) 2131-2138
• 2 Labek G, Thaler M, Janda W, Agreiter M, Stöckl B. Revision rates after total joint replacement: cumulative results from worldwide joint register datasets. J Bone Joint Surg Br 2011; 93 (03) 293-297
• 3 Kurtz SM, Ong KL, Lau E. et al. International survey of primary and revision total knee replacement. Int Orthop 2011; 35 (12) 1783-1789
• 4 Hardeman F, Londers J, Favril A, Witvrouw E, Bellemans J, Victor J. Predisposing factors which are relevant for the clinical outcome after revision total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2012; 20 (06) 1049-1056
• 5 Sharkey PF, Lichstein PM, Shen C, Tokarski AT, Parvizi J. Why are total knee arthroplasties failing today–has anything changed after 10 years?. J Arthroplasty 2014; 29 (09) 1774-1778
• 6 Della Valle C, Parvizi J, Bauer TW. et al; American Academy of Orthopaedic Surgeons. 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 (14) 1355-1357
• 7 Parvizi J, Tan TL, Goswami K. et al. The 2018 definition of periprosthetic hip and knee infection: an evidence-based and validated criteria. J Arthroplasty 2018; 33 (05) 1309-1314
• 8 Engh GA, Ammeen DJ. Classification and preoperative radiographic evaluation: knee. Orthop Clin North Am 1998; 29 (02) 205-217
• 9 Lucey SD, Scuderi GR, Kelly MA, Insall JN. A practical approach to dealing with bone loss in revision total knee arthroplasty. Orthopedics 2000; 23 (10) 1036-1041
• 10 Morgan-Jones R, Oussedik SI, Graichen H, Haddad FS. Zonal fixation in revision total knee arthroplasty. Bone Joint J 2015; 97-B [phone]
• 11 Scuderi GR, Insall JN. Revision total knee arthroplasty: a surgical technique. Surg Technol Int 1999; 8: 227-231
• 12 Scuderi GR. Revision total knee arthroplasty: how much constraint is enough?. Clin Orthop Relat Res 2001; (392) 300-305
• 13 Bin Abd Razak HR, Lee JHM, Tan SM, Chong HC, Lo NN, Yeo SJ. Satisfaction rates are low following revision total knee arthroplasty in Asians despite improvements in patient reported outcome measures. J Knee Surg 2020; 33 (10) 1041-1046
• 14 Hamilton DF, Howie CR, Burnett R, Simpson AH, Patton JT. Dealing with the predicted increase in demand for revision total knee arthroplasty: challenges, risks and opportunities. Bone Joint J 2015; 97-B [phone]
• 15 Oduwole KO, Molony DC, Walls RJ, Bashir SP, Mulhall KJ. Increasing financial burden of revision total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2010; 18 (07) 945-948
• 16 Lavernia C, Lee DJ, Hernandez VH. The increasing financial burden of knee revision surgery in the United States. Clin Orthop Relat Res 2006; 446 (446) 221-226