Reconstruction of Disrupted Extensor Mechanism After Total Knee Arthroplasty

Total Knee Arthroplasty Periprosthetic Joint Infection With Concomitant Extensor Mechanism Disruption and Soft-Tissue Defect: The Knee Arthroplasty Terrible Triad

BACKGROUND

Periprosthetic infection (PJI) with concomitant extensor mechanism disruption (EMD) and soft-tissue defect-hereinafter termed the "Terrible Triad"-is a devastating complication following total knee arthroplasty. The purpose of this study was to define the surgical and clinical outcomes following management of a cohort of patients who have the Terrible Triad.

METHODS

From 2000 to 2022, 127 patients underwent operative management for PJI alone, 25 for PJI with soft-tissue defects (defined as defects requiring flap reconstruction or being a factor contributing to the decision of performing above-knee amputation or arthrodesis), 14 for PJI with EMD, and 22 for the Terrible Triad. A composite outcome of infection status, range of motion, extensor lag, and ambulatory status at final follow-up was used to compare the proportion of patients in each group with a favorable overall knee outcome. Differences between groups were determined using one-way analyses of variance with post hoc Tukey's tests and Pearson's Chi-square tests or Fisher's exact tests with post hoc Bonferroni adjustments, where applicable. Odds ratios (OR) were calculated for comparison of the overall knee outcome between groups. A Kaplan-Meier survival analysis for patient mortality was performed.

RESULTS

The mean follow-up was 8.4 years and similar between groups (P = .064). Patients who had the Terrible Triad had a 45.5% incidence of above-knee amputation, or arthrodesis, and an 86.4% incidence of an unfavorable outcome. Compared to patients in the PJI group, patients in the PJI who had a soft-tissue defect (OR = 5.8, 95% CI [confidence interval] 2.2 to 15.7), PJI with EMD (OR = 3.7, 95%CI 1.0 to 12.9), and Terrible Triad groups (OR = 11.6, 95% CI 3.3 to 41.5) showed higher odds of an unfavorable knee outcome.

CONCLUSIONS

This study demonstrates that the total knee arthroplasty Terrible Triad is a dreaded diagnosis with poor outcomes. Clinicians and patients might consider early treatment with amputation or arthrodesis.

LEVEL OF EVIDENCE

III.

Very High Early Failure Rate Following Primary Repair of Acute Extensor Mechanism Disruption After Total Knee Arthroplasty

BACKGROUND

Extensor mechanism disruption is a devastating complication following total knee arthroplasty (TKA). Despite its morbidity, there is no consensus regarding the optimal treatment strategy. We aimed to determine the survivorship, clinical outcomes, and improvement in patient-reported outcome measures after primary repair of acute extensor mechanism disruptions following primary or revision TKA.

METHODS

A retrospective review identified 41 acute extensor mechanism disruptions (33 primary TKAs and eight revision TKAs) from 2015 to 2021. The study group was 56% women, the mean body mass index was 33, the mean age was 66 years, and the mean follow-up was 3 years. Extensor mechanism disruption occurred at the patellar tendon (n = 17), quadriceps tendon (n = 15), and patella (n = 9) at a mean of 10 months following TKA. Surgical management was primary repair (n = 30) or primary repair with augmentation (allograft or autograft) (n = 11). Kaplan-Meier analysis estimated survivorship.

RESULTS

The 2-year survivorship free from all-cause reoperation was 72 and 23% following primary and revision TKA, respectively (P = 0.013). The 2-year survivorship free from all-cause reoperation was 66% for primary repair versus 61% for primary repair with augmentation (P = 0.95). There were 17 (41%) patients who underwent reoperation, most commonly for rerupture (n = 4) in two primary repairs and two primary repairs with augmentation (P = 0.288). Revision TKA (P = 0.049) and increased time from disruption to repair (P = 0.039) were risk factors for reoperation. Neither did the mean extensor lag significantly improve nor did patients see improvement in their patient-reported outcome measures.

CONCLUSIONS

After primary and revision TKA, acute extensor mechanism disruption treated with primary repair with or without augmentation had very poor early survivorship free from all-cause reoperation. Patients should be counseled appropriately, and alternative surgical techniques should be considered.

Patella Fractures after Total Knee Arthroplasty

Periprosthetic patella fractures are a rare complication that can lead to severe disability following total knee arthroplasty (TKA). There are several factors that increase the risk of this injury, including patient comorbidities, anatomic considerations, and surgical technique. With these factors limiting healing ability in the area, periprosthetic patellar fractures can pose a major challenge to treat, with potentially lasting morbidity for affected patients. These fractures can occur at any time following TKA and are classified based on their associated implant stability and disruption of the extensor mechanism using the Ortiguera and Berry classification system. Each of the three types of fractures can be managed in their own unique way; however, outcomes remain poor, and the complication rates remain high regardless of fracture type. This article provides an overview of the current literature and the recommended management of periprosthetic patella fractures.

Allograft or Synthetic Mesh Extensor Mechanism Reconstruction After TKA Carries a High Risk of Infection, Revision, and Extensor Lag

BACKGROUND

Extensor mechanism disruption is a devastating complication after TKA. Extensor mechanism reconstruction can be performed using an allograft or synthetic mesh. Recent studies have disagreed about the durability of these reconstructions. Evaluating a larger series of reconstructions that use current popular techniques and principles provides information to guide patient and surgeon expectations while bringing to light the potential fate of patients who experience an infection postoperatively.

QUESTIONS/PURPOSES

(1) What was the 5-year survival free of repeat revision surgery or persistent extensor lag of more than 30° after allograft or synthetic mesh reconstruction of extensor mechanism disruptions after TKA, and did this differ between techniques? (2) What was the 5-year survival free of infection after allograft or mesh reconstruction, and what proportion of those patients experienced a secondary severe complication (arthrodesis or amputation)?

METHODS

Between April 2008 and December 2020, 123 patients underwent extensor mechanism reconstruction after TKA at one center. Of those, 37% (45) were lost to follow-up before 2 years, had not been seen in the past 5 years, did not reach a study endpoint (repeat revision or extensor lag > 30°) before that time, or underwent primary repair and thus could not be analyzed, leaving 63% (78) for analysis here. During the study period, we considered extensor mechanism surgery when acute or chronic disruption of the patellar or quadriceps tendon was present or there was a fracture of the patella resulting in extensor lag. The decision to use either mesh or an allograft largely depended on surgeon experience and familiarity with either technique. We collected patient demographics, operative details (location of disruption and presence of a hinged prosthesis), subsequent periprosthetic joint infection (PJI), and postoperative SF-12 and Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, scores. We used Kaplan-Meier survivorship analysis, with endpoints of extensor lag more than 30° or revision of the reconstruction and PJI. The mean follow-up duration was 5.3 ± 3.2 years.

RESULTS

Survivorship free from revision or recurrent extensor lag was 54% (95% CI 44% to 66%) at 5 years. There was no difference between those undergoing reconstruction with allografts and those with mesh in terms of survivorship free from those endpoints at that timepoint (52% [95% CI 40% to 68%] versus 57% [95 CI% 41 to 78%]; p = 0.99). Survivorship free from PJI was 81% (95% CI 73% to 90%) at 2 years. There was no difference between those with allografts and those with mesh in terms of survivorship free from PJI at that timepoint (79% [95% CI 69% to 92%] versus 83% [95% CI 71% to 98%]; p = 0.75). Of the 17 patients who experienced PJI, four ultimately underwent arthrodesis and three more underwent transfemoral amputation.

CONCLUSION

Allograft and synthetic mesh reconstructions commonly left patients with persistent limb dysfunction, while several patients had PJI and some underwent salvage procedures. Although improvements have been made with regard to treating extensor mechanism disruptions, patients and surgeons should be well aware of the potential adverse outcomes when determining management and use these findings to conduct risk-benefit analyses. There is a need for future studies to identify protocols that improve the durability of reconstructions and to determine whether interventions such as prolonged prophylactic antibiotic therapy have a role in minimizing the risk of PJI.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Tibial Tubercle Osteotomy in Revision Total Knee Arthroplasty for Periprosthetic Infection: Indications and Outcomes

BACKGROUND

Adequate exposure is essential in revision total knee arthroplasty (RTKA). Tibial tubercle osteotomy (TTO) enhances exposure, but its use is controversial in the setting of periprosthetic infection. The purposes of this study were to determine (1) the rates of complications and revisions due to TTO during RTKA in the setting of a periprosthetic infection, (2) the rate of septic failure, and (3) functional outcomes at a minimum 2-year follow-up.

METHODS

A single-center retrospective study from 2010 to 2020 was performed. The cases of a total of 68 patients who received a TTO during RTKA in the setting of periprosthetic infection with a minimum follow-up of 2 years (mean, 53.3 months; range, 24 to 117 months) were analyzed. Complications and revisions due to TTO were reported. The functional outcomes were assessed using the Knee Society Score (KSS) and range of motion.

RESULTS

Seven knees (10.3%) had complications secondary to the TTO (3 had fracture-displacement of the TTO; 2, nonunion; 1, delayed union; and 1, wound dehiscence). The mean time to union (and standard deviation) was 3.8 ± 3.2 months (range, 1.5 to 24 months). Two knees (2.9%) underwent a TTO-related revision (1 had wound debridement, and 1 had tibial tubercle osteosynthesis). Eighteen knees (26.5%) had recurrence of infection requiring revision: 17 were managed with debridement, antibiotics, and implant retention (DAIR), and 1 had 2-stage RTKA. Flexion improved after surgery (from a mean of 70° to a mean of 86°; p = 0.009), as did the KSS knee (46.6 to 79; p < 0.001) and function (35.3 to 71.5; p < 0.001) subscores. Overall, 42.6% of infected knees managed with RTKA with the TTO procedure were considered successful without any complication at the last follow-up. Only 2 knees (2.9%) required revision related to the TTO.

CONCLUSIONS

TTO in RTKA involving periprosthetic infection is an effective surgical exposure aid and has excellent rates of union (97.1%) despite the presence of infection. However, the risk of failure because of persistent or recurrent infection remains high in the first 2 years following RTKA for infection.

LEVEL OF EVIDENCE

Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Patellar Tendon Reconstruction Using Peroneus Longus Tendon Autograft Following Revision Knee Arthroplasty: A Case Report

Patellar tendon rupture is a rare but serious complication resulting in loss of knee extension that may develop during and after total knee arthroplasty and negatively affects the patient's quality of life. There are a number of surgical options available, from primary repair to reconstruction. Peroneus longus tendon autograft has begun to be used for knee extensor mechanism repair in recent years. In this case report, we aimed to present the case of a patient with traumatic patellar tendon rupture after revision knee arthroplasty. In conclusion, patellar tendon reconstruction using peroneus longus tendon autograft can be considered a successful method in selected patients following knee arthroplasty. It allows early rehabilitation via stable graft fixation and provides good clinical and functional outcomes in the late period.

Medial gastrocnemius rotational flap for the reconstruction of extensor mechanism disruption in periprosthetic knee infections: a retrospective series with minimum two year follow-up

PURPOSE

Extensor mechanism disruption following total knee arthroplasty has a prevalence ranging from 0.3 to 3%. Its management is challenging, especially in case of associated infection of the prosthetic implant. Surgical options are limited due to the septic process, and the use of allograft or synthetic mesh are not recommended. The aim of this study was to report clinical outcomes, complications, survival, and surgical technique of medial gastrocnemius flap for the treatment of extensor mechanism disruptions associated with periprosthetic knee infection.

METHODS

This is a retrospective study from a prospectively collected arthroplasty registry from 2012 to 2019. Patients who received the gastrocnemius flap in the setting of a two-stage knee replacement for periprosthetic infection were included. Results of physical examination, Knee Society Score, Oxford Knee Score, and measurement of the range of motion registered pre-operatively were compared to those obtained at last follow-up. Survival was analysed through Kaplan-Meier curve.

RESULTS

A total of 15 patients were included, with a mean age of 63.4 years (range 36-77). The reconstruction of the extensor mechanism demonstrated a success rate of 73.3%. The mean extension lag at final follow-up was 7.5° (range, 0-30). The mean Knee Society Score and Oxford Knee Score improved from 29.0 (range, 21-36) and 17.5 (range, 13-22) respectively, to 82.9 (range, 74-89) and 36.0 (range, 33-39).

CONCLUSION

Medial gastrocnemius rotational flap is a reliable option for joint and limb salvage in case of periprosthetic knee infection associated with wide soft tissue degeneration and extensor mechanism disruption. The technique and surgical protocol presented in this study are reproducible and guaranteed good clinical outcomes and infection control.

High rate of failure after revision extensor mechanism allograft reconstruction

BACKGROUND

Patients who fail initial extensor mechanism allograft (EMA) reconstruction for extensor mechanism disruption after total knee arthroplasty (TKA) are left with few options. This study evaluated outcomes in patients that underwent revision EMA reconstruction following a failed EMA.

METHOD

Ten patients that underwent revision EMA for failed index EMA with minimum 1-year follow-up were retrospectively reviewed. Patients receiving fresh-frozen EMA (quadriceps tendon, patella, patellar tendon, and tibial tubercle) at index and revision EMA were included. The primary outcome was EMA failure defined as revision surgery, extensor lag > 30°, or Knee Society Score (KSS) < 60 at last follow-up. Descriptive statistics were performed, with p < 0.05.

RESULTS

Mean extensor lag improved from 55.6°±26.7° pre-revision to 32.8°±29.6° (p = 0.13) at mean follow-up of 43.8 months (range, 12-124 months). Mean KSS improved from 41.0 ± 9.5 pre-revision to 73.4 ± 14.5 at last follow-up (p < 0.001). All patients required assistive devices for ambulation at final follow-up: one (10.0%) required a wheelchair, five (50.0%) required a walker, and four (40.0%) required a cane. Seven (70.0%) patients experienced EMA failure at a mean of 33.6 months (range, 2-124) following revision EMA: three (30.0%) were revised for periprosthetic joint infection (one of which also had extensor lag > 30°), three (30.0%) additional patients had extensor lag > 30°, and one (10.0%) patient had KSS < 60 (this patient developed PJI and was treated nonoperatively with chronic antibiotic suppression).

CONCLUSIONS

Revision EMA reconstruction fails at a high rate despite leading to improvements in KSS. Further research is needed to develop effective prevention and treatment strategies for failure after initial EMA reconstruction.

Satisfactory outcomes of patellar tendon reconstruction using achilles' tendon allograft with bone block after infected total knee arthroplasty

PURPOSE

Extensor mechanism disruption is an uncommon and devastating complication after total knee arthroplasty. It negatively affects patients' quality of life and leads to significant functional limitations and the inability to stand and walk. The purpose of the present study was to evaluate the outcomes of the extensor mechanism reconstruction using Achilles' tendon allograft after infected total knee arthroplasty. It was hypothesized that it is a safe procedure and that patients will present good clinical and functional results.

METHODS

Ten patients treated for infra-patellar extensor mechanism disruption after infected total knee arthroplasty were prospectively followed for two years. The mean age of patients was 70.8 (range 55-85), with a median BMI of 28.72 ± 2.2 kg/m². All patients underwent reconstruction using a fresh frozen Achilles tendon allograft. Preoperative and postoperative evaluation included knee-related clinical and functional assessment based on objective and subjective scores, including the knee flexion, the extension lag, the Knee Society Score (KSS) clinical and functional, and the visual analog scale (VAS) for pain at 12 and 24 months. Radiological evaluation was also performed using the Caton-Deschamps index. Reported complications were also recorded.

RESULTS

Clinical and functional outcomes recorded significant improvements (p < 0.05) at the final follow-up compared with baseline as follows: Knee flexion was improved from 66° ± 4.8 to 99.7° ± 3.9, and the extension lag was decreased from 28.3° ± 4.4 to 9° ± 2.7. The mean KSS clinical and functional were also improved from 22.6 ± 7.9 to 73.4 ± 3.9 and from 10 ± 13.8 to 55 ± 13.8, respectively. The VAS for pain was decreased from 8.1 ± 1.2 to 1.9 ± 1.2. The Caton-Deschamps index demonstrated a tendency to patella Alta. Two treatment failures were recorded, one patellar dislocation and one re-rupture revised to arthrodesis.

CONCLUSIONS

Extensor mechanism reconstruction using Achilles' tendon allograft after infected total knee arthroplasty is an efficient and safe procedure for infra-patellar disruption. The present study's findings demonstrate that most of the patients (80%) presented significant clinical and functional improvement at two-year follow-up.

Extensor Mechanism Reconstruction After Total Knee Arthroplasty with Allograft Versus Synthetic Mesh: A Multicenter Retrospective Cohort

INTRODUCTION

Patellar and quadriceps tendon ruptures after total knee arthroplasty (TKA) have historically poor outcomes. To date, there is no consensus for optimal treatment. The purpose of this study is to directly compare clinical outcomes and survivorship between allograft versus synthetic mesh for reconstruction of native extensor mechanism (EM) rupture after TKA.

METHODS

A multicenter, retrospective review identifying consecutive TKA patients operated between December 2009 to November 2019 was conducted. Patients aged ≥ 45 years old with native EM disruption treated with either allograft or synthetic mesh with minimum 2 year follow-up were included. Demographic information, injury mechanism, range of motion, surgical time, revision surgeries, and postoperative Knee Injury and Osteoarthritis Outcome Scores (KOOS Jr.) were collected. Student t-tests and Fisher exact tests were used to compare the demographic data between groups. The Kaplan-Meier survival curve method was used to determine the survivorship as treatment failure was defined as postoperative EM lag >30° or revision surgery. Survival curves were compared using the log-rank test. Univariate Cox proportional hazard regression identified risk factors associated with treatment failure.

RESULTS

Twenty patients underwent EM reconstruction using allograft versus 35 with synthetic mesh. Both groups had similar demographics and an average follow-up time of 3.5 years (P = 0.98). Patients treated with allograft had significantly greater postoperative flexion than patients treated with mesh (99.4 ± 9.5 allograft versus 92.6 ± 13.6 synthetic mesh, P = 0.04). Otherwise, there was no difference in postoperative outcomes between the two groups in average KOOS Jr. (P = 0.29), extensor lag (P = 0.15), graft failure (P = 0.71), revision surgery rates (P = 0.81), surgical time (P = 0.42), or ambulatory status (P = 0.34) at the most recent follow-up. Survival curve comparison also yielded no difference at up to 5-year follow-up (P = 0.48).

DISCUSSION AND CONCLUSION

Our findings suggest that reconstruction with allograft or synthetic mesh leads to similar clinical outcomes with good survivorship. Future studies, including larger randomized control trials, are required to determine the superior reconstruction method for this injury.

LEVEL OF EVIDENCE

III.

Extensor mechanism reconstruction with allograft following total knee arthroplasty: a systematic review and meta-analysis of achilles tendon versus extensor mechanism allografts for isolated chronic patellar tendon ruptures

BACKGROUND

Extensor mechanism rupture is a severe complication with an incidence of 0.1-2.5% after total knee arthroplasty (TKA). Achilles tendon allograft (ATA) and extensor mechanism allograft (EMA) in TKA surgery have yielded mixed clinical results. Our systematic review aims to identify the proportion of failure in extensor mechanism reconstruction after TKA using allograft and evaluate clinical and functional outcomes and the most common complications. Furthermore, we performed a meta-analysis among studies dealing with isolated patellar tendon ruptures to assess the failure rate, surgical complications, and clinical findings (extensor lag and knee range of motion) of extensor mechanism reconstruction using either ATA or EMA grafts.

METHODS

A systematic review of the literature was performed following the PRISMA guidelines, including the studies dealing with the use of EMA and ATA for extensor mechanism rupture following TKA. Coleman Methodology Score and the MINORS score were used to assess the quality of the studies. A meta-analysis was performed to evaluate the failure rate, complications, and clinical findings (extensor lag and knee range of motion) of the ATA and EMA treatments in isolated patellar tendon ruptures.

RESULTS

A total of 238 patients (245 knees), with a mean age ranging from 54 to 74 years, who underwent extensor mechanism reconstruction with an allograft were identified in the 18 included studies. We analysed 166 patellar tendon ruptures, 29 quadriceps tendon ruptures, and 29 patellar fractures in the analysis. A chronic injury was described in the majority of included cases. ATA and whole EMA were used in 89 patients (92 knees) and 149 patients (153 knees), respectively. The overall failure percentage was 23%, while EMA and ATA were 23 and 24%. The most common complication was extensor lag (≥ 20°). The overall incidence of postoperative infection was 7%. Eleven of 14 included papers reported more than 100° of the mean postoperative knee flexion. The percentage of patients requiring walking aids is 55 and 34.5% in ATA and EMA, respectively. The failure outcome after extensor mechanism reconstruction in isolated patellar tendon ruptures was 27%, with no statistical difference between EMA and ATA in terms of failure rate and clinical outcomes.

CONCLUSIONS

Extensor mechanism reconstruction with allograft represents a valid treatment option in patients with acute or chronic rupture following total knee arthroplasty. Persistent extensor lag represents the most common complication. EMA is associated with a lower frequency of patients requiring walking aids at last follow-up, although it has similar clinical and functional outcomes to ATA. In patellar tendon ruptures, ATA has a comparable success rate with EMA.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

TRIAL REGISTRATION

PROSPERO 2019 CRD42019141574.

Early patellar tendon rupture after total knee arthroplasty: A direct repair method

BACKGROUND

Patellar tendon rupture after total knee arthroplasty (TKA) is a catastrophic complication. Although the occurrence of this injury is rare, it can lead to significant dysfunction for the patient and is very tricky to deal with. There has been no standard treatment for early patella tendon rupture after TKA, and long-term follow-up data are lacking.

AIM

To introduce a direct repair method for early patella tendon rupture following TKA and determine the clinical outcomes and complications of this method.

METHODS

During the period of 2008 to 2021, 3265 consecutive TKAs were retrospectively reviewed. Twelve patients developed early patellar tendon rupture postoperatively and were treated by a direct repair method. Mean follow-up was 5.7 years. Demographic, operative, and clinical data were collected. The clinical outcomes were assessed using the Western Ontario and McMaster Universities (WOMAC) score, the Hospital for Special Surgery (HSS) score, knee range of motion, extensor lag, and surgical complications. Descriptive statistics and paired t test were employed to analyze the data.

RESULTS

For all 12 patients who underwent direct repair for early patellar tendon rupture, 3 patients failed: One (8.3%) for infection and two (17.6%) for re-fracture. The two patients with re-fracture both underwent reoperation to reconstruct the extensor mechanism and the patient with infection underwent revision surgery. The range of motion was 109.2° ± 10.6° preoperatively to 87.9° ± 11° postoperatively, mean extensor lag was 21° at follow-up, and mean WOMAC and HSS scores were 65.8 ± 30.9 and 60.3 ± 21.7 points, respectively.

CONCLUSION

This direct repair method of early patellar tendon rupture is not an ideal therapy. It is actually ineffective for the recovery of knee joint function in patients, and is still associated with severe knee extension lag and high complication rates. Compared with the outcomes of other repair methods mentioned in the literature, this direct repair method shows poor clinical outcomes.

Management of Extensor Mechanism Disruption After Total Knee Arthroplasty

Extensor mechanism disruptions following total knee arthroplasty are devastating injuries with complication rates following surgical intervention ranging from 25% to 45%. Primary repair with and without augmentation is appropriate in certain limited clinical settings. Allograft reconstruction has been a popular option; however, synthetic grafts are showing promise and good results. In this article the authors discuss an algorithm for treating these difficult injuries as well as detail the surgical techniques for each approach.

Techniques for extensor mechanism reconstruction after total knee arthroplasty: Is there a clear winner?

Extensor mechanism (EM) disruption after total knee arthroplasty (TKA) is rare, but can result in devastating outcomes for patients including inability to ambulate. Disruption can occur at the quadriceps tendon, patella, or patellar tendon. This complication can be traumatic, but is often atraumatic from an iatrogenic or degenerative etiology. Primary repair for treatment of EM disruption has led to poor results with high failure rates and has mostly been abandoned. Most commonly accepted techniques center around Achilles tendon allograft reconstruction, synthetic mesh reconstruction, or other smaller options. However, to date, there is still no consensus for the optimal EM reconstructive technique due to the heterogeneity and small sample sizes of published studies. The need to identify a consistent and effective surgical technique is paramount to restore quality of life to patients who suffer from EM disruption after TKA. The purpose of this review is to describe the osteology, vasculature, and EM of the knee, identify risk factors associated with EM disruption after TKA, outline the considerations for surgical management, as well as compare and analyze the latest contributions to the literature, in particular allograft versus synthetic mesh, in the reconstruction of the EM after TKA.

The active knee extension after extensor mechanism reconstruction using allograft is not influenced by "early mobilization": a systematic review and meta-analysis

BACKGROUND

Postoperative rehabilitation after extensor mechanism reconstruction (EMR) with allograft following total knee arthroplasty (TKA) is not standardized. This meta-analysis aimed to evaluate the effectiveness of early and late knee mobilization after EMR. The range of motion (ROM) and extensor lag in both groups were also assessed as the secondary endpoint.

METHODS

Following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines, a systematic review of the literature was performed, including studies dealing with the use of allograft for EMR following TKA. Failure was defined as the persistence of extensor lag > 20°. Coleman Methodology Score and Methodological Index for Non-Randomized Studies (MINORS) score were used to assess the quality of studies included. The failure rate was set as the primary outcome in early (4 weeks) and late (8 weeks) mobilization groups after EMR with allograft. Secondary outcomes were postoperative extensor lag and ROM.

RESULTS

Twelve articles (129 knees) were finally selected for this meta-analysis. Late and early knee mobilization was described in five and seven studies, respectively. No difference was noted between both groups' failure rates (11/84 vs. 4/38, respectively; p = 0.69). The mean extensor lag at last follow-up was 9.1° ± 8.6 in the early mobilization group, and 6.5° ± 6.1 in the late mobilization group is not significantly different (p > 0.05). The mean postoperative knee flexion was 107.6° ± 6.5 and 104.8° ± 7 in the early and late mobilization group, respectively.

CONCLUSION

While immobilization after EMR in TKA is mandatory to allow tissue healing, early knee mobilization after four weeks can be recommended with no additional risk of failure and increased extensor lag compared to a late mobilization protocol.

LEVEL OF EVIDENCE

IV, therapeutic study. Registration PROSPERO (International Prospective Register of Systematic Reviews): CRD42019141574.

Classification and Management of Periprosthetic Patella Fractures

Complications related to the extensor mechanism and patellofemoral joint continue to be the most common cause of pain and indication for surgical revision following total knee arthroplasty. Numerous risk factors related to the patient, implant, and technical performance of the procedure have been identified. The Ortiguera and Berry classification system is widely used for the systematic classification and management of these fractures. Because of the difficult nature of revision surgery for fracture and the high risk of complication, a careful assessment of the fracture and implants is vital to determining the best course of treatment.

Complex ruptures of the quadriceps tendon: a systematic review of surgical procedures and outcomes

Background

Chronic ruptures, ruptures following total knee arthroplasty (TKA), and re-ruptures of the quadriceps tendon (QT) are rare. A systematic review of the current literature was conducted on their treatment and outcome to provide evidence-based indications for their management.

Methods

We searched published articles in English on chronic ruptures of QT, QT ruptures that occurred after TKA, and re-ruptures in PubMed, Scopus, and Google Scholar up to January 2021. Twenty-five articles were included following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Results

Data from 25 articles (97 patients) with a mean age of 57 were retrieved. Patients were classified into three groups depending on the type of rupture: 16 patients suffered chronic QTR, 78 a QTR after a TKA, and 9 patients reported a re-rupture. The most frequent surgical approaches were different for each group: Codivilla’s Y-V technique and end-to-end sutures were the most commonly used in the chronic tears group (62.5%), synthetic MESH was the most frequent choice in QTR after a TKA group (38 patients, 53%), while end-to-end sutures were the first choice in the re-rupture group (4 patients, 44%).

Conclusions

Complex ruptures of the QT can be chronic ruptures, re-ruptures, or ruptures occurring after TKA. The choice of the best surgical technique depends on the macroscopic quality of the tendon stumps rather than the timing of intervention. Evidence-based preventive and therapeutic strategies should be developed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02696-9.

Meta-analysis Comparing Allograft to Synthetic Reconstruction for Extensor Mechanism Disruption after Total Knee Arthroplasty

Extensor mechanism disruption following total knee arthroplasty (TKA) is a devastating complication that causes high failure rates. There is controversy on what is the best way to do an extensor mechanism reconstruction. This study aims to compare both allograft and synthetic reconstructive techniques for success, reoperation, and infection rates and functional outcomes. The search on PubMed, MEDLINE, Embase, BIOSIS, and Cochrane databases was performed on March 15, 2019, using the following keyword groups: (1) "extensor mechanism" and "total knee arthroplasty," (2) "extensor mechanism" and "knee arthroplasty," (3) "extensor mechanism" and "revision total knee arthroplasty," and (4) "extensor mechanism" and "revision knee arthroplasty". Only studies on extensor mechanism disruption after TKA that included sufficient data to compare these two surgical techniques were included. Meta-analysis was performed with random effect model using the DerSimonian-Laird method. Thirty studies were included. The overall success rate of the reconstruction was 73.3% (95% confidence interval [CI]: 0. 651, 0.814). The success rate of allograft (72.8%, 95% CI: 0.626, 0.829) was not significantly different from synthetic material (78%, 95% CI: 0.707, 0.852, p = 0.416). There was no significant difference in revision rates between allograft (14.2%, 95% CI: 0.095, 0.189) and synthetic material (16%, 95% CI: 0.096, 0.223, p = 0.657). The overall relative risk of infection was 4.301 (95% CI: 1.885, 9.810). There was no significant difference in relative risk of infection between allograft (3.886, 95% CI: 1.269, 11.903) and synthetic material (4.851, 95% CI: 1.433, 16.419, p = 0.793). No statistically significant difference was found in mean postoperative Knee Society score (73.109 [95% CI: 67.296, 78.922] vs. 72.679 [95% CI: 69.184, 76.173], p = 0.901) between allograft and mesh reconstruction groups. There were no significant differences in overall failures, infections, functional outcomes, or revision reconstructions between allograft and synthetic material extensor mechanism reconstructions. Our results demonstrate the difficulty in treating this serious injury, independent of technique, as well as the significant risk for overall failure and infection.

Extensor Mechanism Reconstruction Using Allograft Following Total Knee Arthroplasty: A Review of Current Practice

The disruption of the extensor mechanism/apparatus of the knee is a dreaded complication following Total Knee Arthroplasty (TKA). Fresh frozen allograft containing the patella, and peripatellar musculotendinous attachments has emerged as an ideal alternative or salvageable option for the efficient reconstruction of extensor mechanism disrupted following TKA, where repair is almost impossible. However, any allograft implantation is associated with certain complications and extensor apparatus allograft is not the exception. Despite being allogenic, reconstruction of the extensor mechanism of the knee using allograft has given promising results. This narrative review aims to elaborate on the current application of allograft in the reconstruction of the disrupted extensor mechanism following TKA.

[Implantation of a tantalum patella during revision surgery]

OBJECTIVE

The reconstruction or restoration of a functioning patella for active extension and flexion by implantation of a tantalum patella. In spite of larger osseous defects of the patella, the goal is to achieve sufficient extensor mechanism function.

INDICATIONS

Patients who have such a large bone defect in the area of the patella that implantation of a traditional patella replacement is not possible. In addition, patients with a peri-implant fracture of the patella can be treated with a tantalum patella and additional plate osteosynthesis.

CONTRAINDICATIONS

Absence of a cortical basic structure of the patella. Complete loss of the patella or the extensor mechanism. Periprosthetic infection.

SURGICAL TECHNIQUE

The patella is completely excised. Subsequently, the back surface of the patella is milled to anchor the tantalum structure as accurately as possible without cement. This is fixed circularly after desired positioning by means of nonresorbable suture. Finally, the polyethylene back surface replacement is cemented onto the back surface of the tantalum structure.

POSTOPERATIVE MANAGEMENT

The patients have a limitation of flexion of 0-0-90° at 20 kilogram partial weight bearing for 12 weeks after surgery.

RESULTS

A total of 10 patients who received a tantalum patella between 2013 and 2019 were retrospectively included. A tantalum patella was implanted in 9 patients with a large patellar defect. In one case a tantalum patella with additional plate osteosynthesis was implanted to treat a peri-implant fracture of the patella. Loosening of the tantalum patella was observed in 1 patient, while in another patient postoperative arthrofibrosis was observed. In 2 cases a postoperative superficial wound healing disorder was detected. Two patients had a persistent infection with subsequent complete explantation of the prosthesis.

Reconstruction of knee extensor with patellar tendon autograft following intraoperative radiotherapy

BACKGROUND

Patellar tendon autograft after intraoperative extracorporeal radiotherapy has been used for reconstruction of the extensor mechanism following limb-sparing wide tumor resection around the knee. The purpose of this study was to determine the clinical outcome of this reconstruction technique.

METHODS

We retrospectively reviewed six consecutive patients with peripatellar tendon and proximal tibial sarcoma who underwent reconstruction of the knee extensor mechanism. The resection area was planned to be contained with the patellar tendon in order to obtain a wide margin. First, the patella was osteotomized at the midline, and the inferior half of patella, patellar tendon, and tibial tuberosity were excised en bloc. The resected segments were devitalized with intraoperative extracorporeal radiotherapy and reimplanted into the original site. A follow-up evaluation included an assessment of the range of motion, extensor lag, the International Society of Limb Salvage score, and complications.

RESULTS

Six patients were followed up for 121-270 months. One patient underwent an additional reconstruction with total knee arthroplasty due to a collapse of the tibial subchondral bone. A supracondylar fracture of the femur occurred in two patients, and a delayed union of the osteosynthesis site of the tibial shaft was observed in one patient. At the latest follow up, extensor lag had a median of five degrees, and International Society of Limb Salvage scores had a median of 83%. No local recurrence or rupture of the patellar tendon was observed.

CONCLUSIONS

Reconstruction of the knee extensor mechanism using a patellar tendon treated with intraoperative radiotherapy is a reliable and successful method.

Periprosthetic fractures about total knee arthroplasty

Periprosthetic fracture after total knee arthroplasty presents a difficult complication for many orthopaedic surgeons. These fractures occur most frequently around the distal femur followed by the patella and then tibia. These fractures are frequently complicated by poor bone quality or compromised bone due to the presence of the implants. Surgical treatment is typically necessary and requires varied techniques of open fixation, intramedullary fixation, or revision arthroplasty. Outcomes of these injuries vary widely. This review aims to describe the epidemiology, classification, treatment options and outcomes for periprosthetic fractures following total knee arthroplasty.

Conversion of cemented revision total knee prostheses to arthrodesis using custom-made arthrodesis modules that preserve the cemented stem anchorage in patients with long-established extensor mechanism insufficiency: A case series

INTRODUCTION

Long-established extensor mechanism insufficiency that defies reconstruction is a rare, but devastating, complication after revision total knee arthroplasty (RTKA) that may require arthrodesis. For cemented stem guided knee prostheses with firmly attached stems, prosthesis explantation can lead to significant bone stock loss that may, at worst, make knee arthrodesis significantly more difficult or impossible to achieve. Under these circumstances, conversion of the cemented knee prosthesis with custom-made arthrodesis modules that preserve the existing stem anchorage may be a low-risk alternative. This case series presents this type of conversion to arthrodesis, which was performed for patients with a non-reconstructable, long-established extensor mechanism insufficiency.

METHODS

After intraoperatively ascertaining that reconstruction of the extensor mechanism insufficiency was impossible, the inlying revision prosthesis was converted into arthrodesis with custom-made arthrodesis modules, without explanting the cemented stems.

RESULTS

Conversion to arthrodesis was performed in four patients. There was no histopathological or microbiological evidence of a periprosthetic joint infection. Clinical follow-up showed a low level of pain, with a stable knee joint and proper implant position. The Oxford Knee Score increased from 20.5 (95% CI 17-26) to 35.5 (95% CI 30-36) points. The visual analog scale decreased from 5.5 (95% CI 4-7) pre-operatively to 1.5 (95% CI 1-2) points at last follow-up. No implant-specific complications occurred.

CONCLUSIONS

Conversion of cemented RTKA with firmly attached cemented stems, without evidence of loosening, to arthrodesis might be a surgical treatment strategy for patients with a long-established extensor mechanism insufficiency that cannot be reconstructed.

Treatment of Extensor Tendon Disruption After Total Knee Arthroplasty: A Systematic Review

BACKGROUND

Patellar or quadriceps tendon ruptures after total knee arthroplasty constitute a devastating complication with historically poor outcomes. With advances in soft tissue reconstruction and repair techniques, treatment has become more nuanced. Numerous graft options for reconstruction and suture techniques for repair have been described but there is no consensus regarding optimal treatment.

METHODS

A search of PubMed, MEDLINE, Embase, and Scopus was conducted. Articles meeting inclusion criteria were reviewed. Type of intervention performed, type of injury studied, outcome measures, and complications were recorded. Quantitative and qualitative analyses were performed.

RESULTS

Twenty-eight articles met inclusion criteria. The complication rate after repair of patellar tendon (63.16%) was higher than the complication rate after repair of quadriceps tendon (25.37%). However, the complication rate for patellar and quadriceps tendon tears after autograft, allograft, or mesh reconstruction was similar (18.8% vs 19.2%, respectively). The most common complication after extensor mechanism repair or reconstruction was extension lag of 30° or greater (45.33%). This was followed by re-rupture and infection (25.33% and 22.67%, respectively). Early ruptures had a higher overall complication rate than late injuries.

CONCLUSION

Extensor mechanism disruption after total knee arthroplasty is a complication with high morbidity. Reconstruction of patellar tendon rupture has a much lower complication rate than repair. Our findings support the recommendation of patellar tendon reconstruction in both the early and late presentation stages. Quadriceps rupture can be treated with repair in early ruptures or with reconstruction in the late rupture or in the case of revision surgery.

Revision knee complexity classification-RKCC: a common-sense guide for surgeons to support regional clinical networking in revision knee surgery

PURPOSE

There is considerable variation in practice throughout Europe in both the services provided and in the outcomes of Revision Knee Surgery. In the UK, a recent report published called get it right first time (GIRFT) aims to improve patient outcomes through providing high quality, cost-effective care, and reducing complications. This has led to the development of a classification system that attempts to classify the complexity of revision knee surgery, aiming to encourage and support regional clinical networking.

METHODS

The revision knee classification system (RKCC) incorporates not only complexity, but also patient factors, the presence of infection, the integrity of the extensor mechanism, and the soft tissues. It then provides guidance for clinical network discussion. Reliability and reproducibility testing have been performed to establish the inter- and intra-observer variabilities using this classification.

RESULTS

Good correlation between first attempt non-expert and experts, good intra-observer variability of non-expert, and an excellent correlation between second attempt non-expert and experts has been achieved. This supports the use of RKCC by both inexperienced and experienced surgeons.

CONCLUSIONS

The revision knee complexity classification has been proposed that offers a common-sense approach to recognize the increasing complexity in revision TKR cases. It provides a methodological assessment of revision knee cases and support regional clinical networking and triage of appropriate cases to revision units or specialist centres.

LEVEL OF EVIDENCE

Expert opinion, Level V.

Treatment of late Patella Baja after an otherwise routine total knee arthroplasty

There is very little data on the incidence or treatment options for late developing patella baja following uncomplicated total knee arthroplasty (TKA). In this article we present the course, surgical treatment, rationale, and one-year outcome of our treatment of this complication with extensor mechanism allograft reconstruction. In our patient, the index TKA produced good results in the early postoperative period, but the patient went on to develop pain, decreased range of motion (ROM), and patella baja, which was resistant to extensive physical therapy and MUA. This was treated successfully with an extensor mechanism allograft, which restored normal patellar height relationships.

Allograft Reconstruction of the Extensor Mechanism after Resection of Soft Tissue Sarcoma

INTRODUCTION

Soft tissue tumors around the knee joint still pose problems for the excision and subsequent reconstruction.

METHODS

In the 6 included patients the soft tissue sarcoma has its base on the anterior surface of the extensor mechanism and expands towards the skin. The entire extensor apparatus (quadriceps tendon, patella, and patellar tendon) was resected and replaced by a fresh-frozen allograft.

RESULTS

The mean follow-up was 6.7 years (range: 2-12.4 years). In two patients a local recurrence occurred, resulting in a 5-year local recurrence-free rate of 66.7% (95% CI: 19.5%-90.4%). Distant metastases were found in 4 patients resulting in a 5-year metastasis-free rate of 33.3% (95% CI: 4.6%-67.5%). Two patients underwent at least one revision surgery, including one patient in whom the allograft had to be removed. According to the ISOLS function score 24.7 points (range: 19-28 points) were achieved at the last follow-up. The mean active flexion of the knee joint was 82.5° (range: 25-120°) and a mean extension lag of 10° (range: 0-30°) was observed.

CONCLUSIONS

The replacement of the extensor mechanism by an allograft is a reasonable option, allowing wide margins and restoration of active extension in most patients.

TRIAL REGISTRATION

The presented study is listed on the ISRCTN registry with trial number ISRCTN63060594.