Revision osteochondral allograft transplantations: do they work?

Midterm Outcomes After Osteochondral Allograft Transplantation in the Knee Using High-Chondrocyte Viability Grafts

BACKGROUND

Osteochondral allograft transplantation (OCAT) has become a standard-of-care treatment option for patients with large symptomatic articular defects. Recent advances in allograft science and OCAT protocols have been reported to result in consistently robust outcomes after OCAT in the knee. However, only short-term comparisons have been reported, and analyses are lacking for treatment failure risk factors that account for confounding variables.

HYPOTHESIS

Midterm functional graft survival rate would exceed 80% for all OCATs combined, with consideration of risk factors for lower survivorship including older patient age, higher body mass index (BMI), tibiofemoral bipolar OCAT, and nonadherence to prescribed postoperative rehabilitation protocols.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients with outcome data available at ≥5 years after primary OCAT using high chondrocyte-viability (HCV) osteochondral allografts were analyzed according to 2 clinically relevant definitions: (1) initial treatment failure, defined by revision or arthroplasty surgery performed for the primary OCAT at any time point during the study period; and (2) functional graft failure, defined by documented conversion to arthroplasty after primary or revision OCAT at any time point during the study period. Analyses were used to assess outcomes for each definition, separately for age group, sex, obesity status, tobacco use, type of OCAT surgery, osteotomy status, concurrent ligament surgery status, and adherence to postoperative protocols. Kaplan-Meier analyses were used to assess differences in survival rates, and Cox proportional hazards models were used to assess risk factors and multivariable relationships with survival. Patient-reported outcome measures for pain, function, mobility, and satisfaction were also analyzed.

RESULTS

Analysis included 137 primary knee OCATs performed in 134 patients with a mean follow-up of 66 months (59 female, 75 male; mean age, 37.8 years; mean BMI, 28.5). The midterm (5- to 8-year) functional graft survival rate for patients undergoing primary OCAT in the knee using HCV grafts was 82% for all cases combined, ranging from 69% for tibiofemoral bipolar HCV OCATs to 89% for patellofemoral bipolar, 94% for multisurface unipolar, and 97% for single-surface unipolar. Initial treatment failure rates (revision or arthroplasty after primary OCAT) and OCAT nonsurvival rates (arthroplasty after primary or revision OCAT) were greater for older patient age, concurrent ligament reconstruction, tibiofemoral bipolar OCAT, and nonadherence to the prescribed postoperative rehabilitation protocols. When adjusted for patients' age, BMI, and tobacco use status, different surgery types did not demonstrate an increased risk for failure, while concurrent ligament reconstruction and nonadherence did. Patients who experienced functional graft survival after primary OCAT reported significantly greater improvements in PROMIS Physical Function and Mobility (Patient-Reported Outcomes Measurement Information System), International Knee Documentation Committee questionnaire, and Single Assessment Numeric Evaluation scores such that they were significantly higher at final follow-up as compared with patients who required arthroplasty. Patient-reported improvements in pain, function, and mobility exceeded minimal clinically important differences for ≥5 years after primary OCAT. When asked if they were satisfied with primary OCAT surgery, 76.2% of patients were very satisfied or satisfied with their results, while 8.5% were neutral and 15.4% were unsatisfied or very unsatisfied.

CONCLUSION

With use of HCV osteochondral allografts, midterm (5- to 8-year) functional graft survival rates for patients undergoing primary OCAT in the knee were notably higher than previously reported midterm rates for traditional OCATs. When adjusted for patient characteristics, risk factors for nonsurvival included concurrent ligament reconstruction for knee instability and nonadherence to the prescribed postoperative rehabilitation protocols. Patients who experienced functional graft survival for ≥5 years after primary OCAT reported statistically significant and clinically meaningful improvements in pain, function, and mobility.

Treatment failures (revision or arthroplasty) after knee osteochondral allograft transplantation with minimum two-year follow-up

BACKGROUND

Knee osteochondral allograft transplantation (OCAT) has been associated with good short- to mid-term outcomes, however, treatment failures occur more frequently than desired. This study used data from a lifelong outcomes registry to analyze knee OCAT treatment failure rates, variables associated with knee OCAT treatment failures, and outcomes after revision or arthroplasty surgery for knee OCAT treatment failures.

METHODS

Patient outcomes were followed after knee OCAT performed using standard preservation (SP) or Missouri Osteochondral Preservation System (MOPS®) allografts. The study population consisted of patients undergoing primary OCAT with ≥ 2-year follow-up. For comparisons, the treatment failure population was defined by patients in the study population with documented treatment failure (revision or arthroplasty) with ≥ 2-year follow-up after failure. Functional graft survival was defined as no further need for revision surgery after primary or revision OCAT.

RESULTS

A total of 262 patients (n = 136 males; 51.9%) were analyzed. SP grafts were used for 59 cases and MOPS grafts were used for 203 cases. Treatment failure was documented in 61 cases (23.3%). MOPS grafts were 3.3 times more likely to be associated with functional graft survival. SP grafts, older patient age, higher BMI, tibiofemoral bipolar OCAT and non-adherence to the postoperative rehabilitation protocol were significantly associated with treatment failure.

CONCLUSIONS

Knee OCAT resulted in functional graft survival at short- to mid-term follow-up in the majority (70-88%) of cases. In addition, revision of primary OCAT resulted in functional graft survival for at least 2 years after revision surgery in the majority (66%) of patients.

LEVEL OF EVIDENCE

2, prospective cohort study.

Surgical Management of Failed Articular Cartilage Surgery in the Knee

Failure rates of cartilage restoration surgery range from 14% to 43%. When failure of prior cartilage restoration surgery is suspected, a thorough clinical workup should be performed to assess the timing and duration of symptoms. Attention should be paid to patient risk factors such as age, body mass index, and smoking status. Concomitant pathology such as malalignment, ligament insufficiency, and meniscus status must be evaluated before revision surgery. As outlined in our treatment algorithm, the size/location of the lesion and the type of primary procedure will guide planning for revision procedures. [Orthopedics. 2023;46(5):262-272.].

Revision Lateral Femoral Condyle Osteochondral Allograft Transplantation With the Snowman Technique After Failed Previous Oblong Osteochondral Allograft

Osteochondral allograft transplantation provides components of both cartilage and subchondral bone and can be used in large and multifocal defects where autologous procedures are limited by donor-site morbidity. Osteochondral allograft transplantation is particularly appealing in the management of failed cartilage repair, as larger defects and subchondral bone involvement are often present, and the use of multiple overlapping plugs might be considered. The described technique provides our preoperative workup and reproducible surgical approach for patients who have undergone previous osteochondral transplantation with graft failure and are young, active patients who would not be otherwise suited for a knee arthroplasty procedure.

Femoral condyle resurfacing using an inlay metal implant: low revision rate of 266 patients in a 5-10 years follow-up

PURPOSE

To assess the clinical outcome and survival of an inlay resurfacing prosthesis for focal femoral condyle chondral and osteochondral defects.

METHODS

Two hundred sixty-six patients (mean age, 38.25 years; range 25-56 years) with symptomatic femoral condyle chondral and osteochondral defects were reviewed. The mean follow-up period was 7.3 years (range 5-10 years). The medial femoral condyle was involved in 229 and the lateral condyle in 37 patients. Previous cartilage surgery was done in 235 patients. All patients were treated with focal femoral condyle resurfacing with the HemiCAP^® device. The preoperative and the last follow-up values of the Knee Injury and Osteoarthritis Outcome Score (KOOS), Oxford Knee Score (OKS), 36-item Short Form Survey (SF-36) and Visual Analogue Scale (VAS) were examined. Complications, reoperation rate and survival were analyzed.

RESULTS

At the last follow-up, all clinical score values showed significant improvement as compared with the corresponding preoperative values (p < 0.001). Age presented a negative correlation with KOOS (p = 0.03) and SF-36 improvement (p = 0.014). Kellgren-Lawrence grade influenced OKS (p = 0.036). BMI, gender, side, medial or lateral condyle and size did not affect the outcome. Patients who had previous biological cartilage procedures demonstrated better clinical improvement in comparison with those that did not have prior surgery (p < 0.05). Survival was 96.2% at 10 years, using as endpoint implant revision or/and progression of osteoarthritis. The cumulative hazard for any-reason reoperation was 12.0%.

CONCLUSIONS

Femoral condyle resurfacing using the HemiCAP^® device is an effective treatment option to address focal chondral and osteochondral defects. It can be successfully used either as a primary procedure or after prior biological cartilage reconstruction. Subjective clinical outcomes are expected to be good to excellent in mid- to long term, while reoperation and revision rates are low. Progression of osteoarthritis is the most common mode of failure; thus, patient selection is very important.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Osteochondral Allografts in Knee Surgery: Narrative Review of Evidence to Date

Knee articular cartilage defects can result in significant pain and loss of function in active patients. Osteochondral allograft (OCA) transplantation offers a single-stage solution to address large chondral and osteochondral defects by resurfacing focal cartilage defects with mature hyaline cartilage. To date, OCA transplantation of the knee has demonstrated excellent clinical outcomes and long-term survivorship. However, significant variability still exists among clinicians with regard to parameters for graft acceptance, surgical technique, and rehabilitation. Technologies to optimize graft viability during storage, improve osseous integration of the allograft, and shorten recovery timelines after surgery continue to evolve. The purpose of this review is to examine the latest evidence on treatment indications, graft storage and surgical technique, patient outcomes and survivorship, and rehabilitation after surgery.

Association of Sex Mismatch Between Donor and Recipient With Graft Survivorship at 5 Years After Osteochondral Allograft Transplantation

BACKGROUND

Sex mismatch between donor and recipient has been considered a potential contributor to adverse outcomes after solid organ transplantation. However, the influence of sex mismatching in osteochondral allograft (OCA) transplantation has yet to be determined.

PURPOSE

To evaluate whether donor-recipient sex mismatching affects graft survival after OCA transplantation.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

In this review of prospectively collected data, patients who underwent OCA transplantation between November 2013 and November 2017 by a single surgeon were analyzed. Cumulative survival was assessed via the Kaplan-Meier method using log-rank tests to compare patients with similar donor groups. Multivariable Cox regression analysis adjusted for patient age, graft size, and body mass index was used to evaluate the influence of donor-recipient sex on graft survival.

RESULTS

A total of 154 patients were included: 102 (66.2%) who received OCAs from a same-sex donor and 52 (33.8%) who received OCAs from a different-sex donor. At 5-year follow-up, a significantly lower graft survival rate was observed for different-sex donor transplantation in comparison with same-sex donorship (63% vs 92%; P = .01). When correcting for age, graft size, and body mass index, donor-recipient sex-mismatch transplantation demonstrated a 2.9-times greater likelihood to fail at 5 years compared with donor-recipient same-sex transplantation (95% CI, 1.11-7.44; P = .03). A subgroup analysis showed no significant difference in graft survival between the female-to-female and female-to-male groups (91% and 84%, respectively). Conversely, male-to-male transplantation demonstrated a significantly higher cumulative 5-year survival (94%; P = .04), whereas lower survival was found with male-to-female donorship (64%; P = .04). Multivariable Cox regression indicated a 2.6-times higher likelihood of failure for the male-to-female group in comparison with the other groups (95% CI, 1.03-6.69; P = .04). Male-to-male transplantation had a tendency toward decreased likelihood of OCA failure (hazard ratio, 0.33), although without statistical significance (95% CI, 0.11-1.01; P = .052).

CONCLUSION

Mismatch between donor and recipient sex had a negative effect on OCA survival after transplantation, particularly in those cases when male donor tissue was transplanted into a female recipient.

Prior Bone Marrow Stimulation Surgery Influences Outcomes After Cell-Based Cartilage Restoration: A Systematic Review and Meta-analysis

Background:

Cell-based cartilage restoration with autologous chondrocyte implantation (ACI) is a safe and effective treatment for symptomatic cartilage lesions. Many patients undergoing ACI have a history of prior surgery, including bone marrow stimulation (BMS). There is mounting evidence that a history of prior BMS may impede healing of the ACI graft.

Purpose/Hypothesis:

The purpose of this study was to compare the failure rates of primary ACI with ACI after prior BMS. We hypothesized that ACI after BMS would have a significantly higher failure rate (defined as reoperation, conversion to arthroplasty, and/or imaging-based failure) compared with primary ACI.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A literature search was performed by use of PubMed and Embase databases for relevant articles published through October 2, 2020, to identify studies evaluating outcomes and failures rates of ACI after prior BMS in the knee.

Results:

Included were 11 studies comprising 1479 ACI procedures. The mean age at surgery ranged from 18.3 to 39.1 years, and the mean follow-up ranged from 3 to 20.6 years. All studies reported failure rates. The overall failure rate was significantly higher in the patients who underwent ACI after BMS, at 26.4% compared with 14.8% in the ACI group (P < .001). Meta-analysis demonstrated an increased risk of failure in patients with a history of prior BMS (log odds ratio = –0.90 [95% confidence interval, –1.38 to –0.42]).

Conclusion:

This systematic review demonstrated that failure rates were significantly higher for patients treated with ACI after BMS relative to patients undergoing ACI without prior BMS. This finding has important implications when considering the use of BMS for defects that are amenable to cell-based restoration and when determining treatment options after failed BMS.

Registration:

PROSPERO (CRD42020180387).

Fresh Osteochondral Allograft Transplantation in Osteochondritis Dissecans in the Knee Joint

Osteochondritis dissecans (OCD) is a chronic and painful joint condition that can occur from childhood through to adult life. Microtrauma, vascular insufficiency, or abnormal endochondral ossification are the most common causes of OCD. Reconstructive techniques for OCD of the knee are typically necessary when either non-operative or reparative/regenerative operative treatments fail, or when the OCD is irreversible. To analyze the clinical outcomes and failure rates of fresh osteochondral allograft transplantation (FOCA) used as a reconstructive strategy in OCD patients, an in-depth search was carried out on the PubMed, Scopus, and Web of Science databases concerning the existing evidence related to the use of FOCA for OCD patients in the knee joint. A total of 646 studies were found through the search and 2 studies were added after a cross-referenced examination of the articles within the bibliography. Six studies with a total of 303 OCD lesions treated with FOCA, with a mean follow-up of 6.3 years, were included. Although a limited number of low-level evidence studies on this topic are available in previous research, satisfactory clinical results and survival rates of the reconstruction are reported. However, to better define the real advantages of FOCA in the healing process of OCD lesions, comparative studies with different techniques are needed.

Clinical Outcomes after Revision of Autologous Chondrocyte Implantation to Osteochondral Allograft Transplantation for Large Chondral Defects: A Comparative Matched-Group Analysis

OBJECTIVE

Osteochondral allograft transplantation (OCA) is a well-established procedure for patients with symptomatic cartilage defects in the knee. Revision to OCA after prior failed cartilage repair has shown similar clinical outcomes as primary OCA; however, most of the failed procedures were arthroscopic procedures for smaller defects. There is no literature investigating the clinical outcomes after OCA for prior failed autologous chondrocyte implantation (ACI) for the treatment of large chondral defects of the knee. The purpose of this study was therefore to determine clinical outcomes of patients undergoing revision to OCA after prior failed ACI as compared with a matched cohort of patients undergoing OCA as a primary cartilage repair procedure (primary OCA).

DESIGN

In this review of prospectively collected data, we analyzed data from 26 patients with at least 2 years follow-up. Thirteen patients who underwent revision to OCA after prior failed ACI by a single surgeon were compared with a matched group of patients who underwent primary OCA. The patients were matched per age, gender, body mass index, and defect size. Patient-reported outcomes, reoperations, and survival rates were compared between groups.

RESULTS

There were no significant differences in patient-reported clinical outcome scores between the groups at final follow-up. Moreover, there was no significant difference in reoperation rates and survival rates between the groups.

CONCLUSION

The present study demonstrates that revision to OCA is a viable treatment option with favorable functional outcomes and similar reoperation and survival rate as primary OCA even for revision of large chondral defects previously treated with ACI.

Metrics of OsteoChondral Allografts (MOCA) Group Consensus Statements on the Use of Viable Osteochondral Allograft

Background:

Osteochondral allograft (OCA) transplantation has evolved into a first-line treatment for large chondral and osteochondral defects, aided by advancements in storage protocols and a growing body of clinical evidence supporting successful clinical outcomes and long-term survivorship. Despite the body of literature supporting OCAs, there still remains controversy and debate in the surgical application of OCA, especially where high-level evidence is lacking.

Purpose:

To develop consensus among an expert group with extensive clinical and scientific experience in OCA, addressing controversies in the treatment of chondral and osteochondral defects with OCA transplantation.

Study Design:

Consensus statement.

Methods:

A focus group of clinical experts on OCA cartilage restoration participated in a 3-round modified Delphi process to generate a list of statements and establish consensus. Questions and statements were initially developed on specific topics that lack scientific evidence and lead to debate and controversy in the clinical community. In-person discussion occurred where statements were not agreed on after 2 rounds of voting. After final voting, the percentage of agreement and level of consensus were characterized. A systematic literature review was performed, and the level of evidence and grade were established for each statement.

Results:

Seventeen statements spanning surgical technique, graft matching, indications, and rehabilitation reached consensus after the final round of voting. Of the 17 statements that reached consensus, 11 received unanimous (100%) agreement, and 6 received strong (80%-99%) agreement.

Conclusion:

The outcomes of this study led to the establishment of consensus statements that provide guidance on surgical and perioperative management of OCAs. The findings also provided insights on topics requiring more research or high-quality studies to further establish consensus and provide stronger evidence.

Shorter Storage Time Is Strongly Associated With Improved Graft Survivorship at 5 Years After Osteochondral Allograft Transplantation

BACKGROUND

Current regulations surrounding the use of osteochondral allografts (OCAs) in the United States require delayed graft release after 14 days to complete infectious disease screening. With a generally accepted expiration time of 28 days in storage, a limited window from 14 to 28 days remains for implantation. Yet, the rates of graft survival and thus optimal time for transplantation within this window remain largely unknown.

HYPOTHESIS

OCAs transplanted within 19 to 24 days would have lower failure rates at 5 years than those transplanted at 25 to 27 days.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

In this retrospective case series, we analyzed data from patients who underwent OCA transplantation (N = 111) by a single surgeon between February 2014 and December 2016 with at least 2-year follow-up. In total, 56 patients received early transplant grafts (storage time, 19-24 days), and 55 received late transplant grafts (storage time, 25-27 days). Survival analysis with Kaplan-Meier curves was performed using log-rank analysis to compare the groups. Multivariable Cox regression analysis was used to assess the influence of OCA storage duration on graft survival while adjusting for age and defect size. Optimal storage time cutoff associated with graft failure was identified by performing receiver operating characteristic curve analysis and calculating the area under the curve.

RESULTS

Patients in the late transplant group had a significantly lower rate of graft survival at 5 years postoperatively (70.4%) as compared with patients in the early transplant group (93.1%; P = .027). When correcting for patient age and defect size, late transplant OCAs demonstrated a 3.4-times greater likelihood of failure versus early transplant OCAs. Receiver operating characteristic analysis suggested that OCA transplantation should ideally occur before 25 days of graft storage.

CONCLUSION

OCA transplantation is a safe and successful treatment option for large osteochondral defects of the knee, with excellent rates of in situ graft survival at 5 years. Prioritizing early transplantation of OCAs to <25 days in storage improves rates of graft survival.

Use of Allografts in Orthopaedic Surgery: Safety, Procurement, Storage, and Outcomes

The use of allografts has become a vital option for orthopaedic surgeons in the treatment of a variety of musculoskeletal lesions, ranging from osteochondral defects in the glenohumeral joint to meniscal deficiency in the young athlete. Nevertheless, barriers to treating a patient with an allograft-based procedure may arise from concerns over disease transmission, the navigation of tissue banks that supply allografts, the process of obtaining insurance approval, or optimal storage methods. This review serves to support orthopaedic surgeons in the incorporation of allografts into their practice by quelling these potential concerns. Fresh osteochondral allografts, fresh-frozen meniscal allografts, soft tissue allografts, and off-the-shelf cartilage products are the focus of this review amid broad overviews of allograft safety and tissue bank practices in the United States.

Survival Analysis of Revision Autologous Chondrocyte Implantation for Failed ACI

BACKGROUND

Autologous chondrocyte implantation (ACI) provides a successful outcome for treating articular cartilage lesions. However, there have been very few reports on the clinical outcomes of revision ACI for failed ACI.

PURPOSE

To evaluate clinical outcomes in patients who underwent revision ACI of the knee for failure of an initial ACI and to determine the factors affecting the survival rate.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A review of a prospectively collected data set was performed from patients who underwent revision ACI of the knee for failure of an initial ACI between 1995 and 2014 by a single surgeon. The authors evaluated 53 patients (53 knees; mean age, 38 years) over a mean 11.2-year follow-up (range, 2-20). A total of 62 cartilage lesions were treated for failed graft lesions after an initial ACI, and 31 new cartilage lesions were treated at revision ACI, as there was progression of disease. Overall, 93 cartilage lesions (mean, 1.8 lesions per knee) with a total surface area of 7.4 cm² (range, 2.5-18 cm²) per knee were treated at revision ACI. Survival analysis was performed with the Kaplan-Meier method, with ACI graft failure or conversion to a prosthetic arthroplasty as the endpoint. The modified Cincinnati Knee Rating Scale, Western Ontario and McMaster Universities Osteoarthritis Index, visual analog scale, and 36-Item Short Form Health Survey were used to evaluate clinical outcomes. Patients also self-reported knee function and satisfaction. Standard radiographs were evaluated with Kellgren-Lawrence grades.

RESULTS

Survival rates were 71% and 53% at 5 and 10 years, respectively. Survival subanalysis revealed a trend that patients without previous cartilage repair procedures before an initial ACI had better survival rates than those with such procedures (81% vs 62% at 5 years, 64% vs 42% at 10 years, P = .0958). Patients with retained grafts showed significant improvement in pain and function, with a high level of satisfaction. At a mean 5.1 years postoperatively, 18 of 27 successful knees were radiographically assessed with no significant osteoarthritis progression. Outcomes for 26 patients were considered failures (mean, 4.9 years postoperatively), in which 15 patients had prosthetic arthroplasty (mean, 4.6 years) and the other 11 patients had revision cartilage repair (mean, 5.4 years) and thus could maintain their native knees.

CONCLUSION

Results of revision ACI for patients who failed ACI showed acceptable clinical outcomes. Revision ACI may be an option for young patients after failed initial ACI, particularly patients without previous cartilage repair procedures and those who desire to maintain their native knees.

Editorial Commentary: Revising a Failed Osteochondral Allograft-Further Down the Rabbit Hole We Go…

Fresh osteochondral allografting has gained popularity as a useful technique for managing difficult cartilage repair problems and, in revision situations, is a treatment of choice when other procedures such as microfracture, osteochondral autograft transfer, and cell-based therapies fail. However, it is a challenge when an allograft fails. Absent substantial progression of osteoarthritis, revising with another allograft results in a reasonable chance of "success" (but a high likelihood of further surgery along the way). Thus, in the setting of a failed osteochondral allograft, sometimes the best option is to keep going further down the rabbit hole and revise a failed allograft with an allograft.

Clinical Outcomes of Revision Osteochondral Allograft Transplantation

PURPOSE

To assess the survivorship, clinical outcomes, and radiographic outcomes of patients who have undergone revision osteochondral allograft (OCA) to the knee in a retrospective case series.

METHODS

Nine patients who underwent revision OCA by the senior author between January 2003 and December 2015 with a minimum follow up of 2 years were reviewed retrospectively. Patients completed patient-reported outcome surveys containing the visual analog scale, the International Knee Documentation Committee, the Knee injury and Osteoarthritis Outcome Score, Lysholm score, and the Short-Form 12. Radiographic analysis included anteroposterior view graded via the Kellgren and Lawrence scale. Complications and reoperations were analyzed, with failure defined as conversion to arthroplasty. (Institutional review board 15050301.) RESULTS: One of 10 consecutive patients was lost to follow up, for an overall follow-up rate of 90% (5 males, 4 females); mean follow up, 4.53 ± 3.17 years. The median patient age at the time of revision OCA was 33 years (interquartile range [IQR], 8.6), the median defect size was 4.0 cm² (IQR, 0), and the median time from index OCA to revision OCA was 2.9 years (IQR, 1.9). Five patients (50%) underwent subsequent surgery at a median of 1.92 years (IQR, 7.25), with 1 progressing to arthroplasty at 23 months after revision OCA, for an overall failure rate of 11%. There were no significant differences in any of the patient-reported outcome assessments compared with prerevision OCA (postindex OCA) values at final follow up (P > .05 for all). Similarly, there were no significant differences in Kellgren and Lawrence score before and after surgery (P = .1).

CONCLUSIONS

At a mean 4.5 years following revision OCA, there was an 89% graft survivorship rate in a series of 9 patients, with no statistical changes in the radiographic progression of arthritis.

LEVEL OF EVIDENCE

Level IV, case series.

Pulse Lavage Fails to Significantly Reduce Bone Marrow Content in Osteochondral Allografts: A Histological and DNA Quantification Study

BACKGROUND

Current clinical practice calls for pulse lavage of fresh osteochondral allografts (OCAs) to reduce immunogenicity; however, there is limited evidence of its effectiveness in reducing allogenic bone marrow elements.

PURPOSE

To evaluate the effectiveness of pulse lavage in removing marrow elements from trabecular bone in fresh OCA transplantation.

STUDY DESIGN

Controlled laboratory study.

METHODS

The authors evaluated 48 fresh OCA plugs with 4 different common sizes (14- and 24-mm diameter, 6- and 10-mm thickness). Within each size group, half of the samples underwent pulse lavage (n = 6) with saline solution and half were left untreated (no lavage; control group, n = 6). For each treatment and size group, 3 samples were analyzed for DNA content as an indicator of the number of residual nucleated cells; the other 3 samples were histologically analyzed to assess the presence and distribution of cells within subchondral bone pores in 3 specific locations within the plug: peripheral, intermediate, and core.

RESULTS

Osteochondral plugs treated with pulse lavage did not show a significant decrease in DNA content in comparison with untreated plugs. Overall, histological analysis did not show a significant difference between the treated and untreated groups (P = .23). Subgroup analysis by size demonstrated decreased marrow content in treated versus untreated groups in the thinner plug sizes (14 × 6 mm and 24 × 6 mm). Histological evaluation by zone demonstrated a significant difference between groups only in the peripheral zone (P = .04).

CONCLUSION

Pulse lavage has limited effectiveness in removing marrow elements, in particular in plugs that are larger in diameter and, more importantly, in thickness. Better techniques for subchondral bone treatment are required for more thorough removal of potentially immunogenic marrow elements.

CLINICAL RELEVANCE

OCA transplantation has become an established treatment modality. Unfortunately, OCA is not without limitations, chiefly its mode of failure through inadequate integration of the allograft subchondral bone with subsequent collapse. In an effort to improve integration, current clinical practice calls for pulse lavage to remove allogenic bone marrow from the subchondral bone in hopes of decreasing the immunogenicity of the graft and facilitating revascularization.

The cost-effectiveness of osteochondral allograft transplantation in the knee

PURPOSE

Osteochondral allografts (OCA) consist of a layer of hyaline cartilage and a layer of underlying bone. They are used to repair combined defects of articular cartilage and bone. Such defects often occur in people far too young to have knee arthroplasty, for whom the main alternative to OCA is conservative symptomatic care, which will not prevent development of osteoarthritis. The aim of this report was to assess the cost-effectiveness of osteochondral allograft transplantation in the knee.

METHODS

Systematic review of evidence on clinical effectiveness and economic modelling.

RESULTS

The evidence on osteochondral allograft transplantation comes from observational studies, but often based on good quality prospective registries of all patients having such surgery. Without controlled trials, it was necessary to use historical cohorts to assess the effect of osteochondral grafts. There is good evidence that OCA are clinically effective with a high graft survival rate over 20 years. If an OCA graft fails, there is some evidence that revision with a second OCA is also effective, though less so than primary OCA. Economic modelling showed that osteochondral allograft transplantation was highly cost-effective, with costs per quality adjusted life year much lower than many other treatments considered cost effective.

CONCLUSIONS

Osteochondral allograft transplantation appears highly cost-effective though the cost per quality adjusted life year varies according to the widely varying costs of allografts. Based on one small study, revision OCA also appears very cost-effective, but more evidence is needed.

LEVEL OF EVIDENCE

II.

Clinical Outcomes and Failure Rates of Osteochondral Allograft Transplantation in the Knee: A Systematic Review

BACKGROUND

Cartilage lesions are a significant cause of morbidity and impaired knee function; however, cartilage repair procedures have failed to reproduce native cartilage to date. Thus, osteochondral allograft (OCA) transplantation represents a 1-step procedure to repair large chondral defects without the donor site morbidity of osteochondral autograft transplantation.

PURPOSE

To perform a systematic review of clinical outcomes and failure rates after OCA transplantation in the knee at a minimum mean 2 years' follow-up.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the literature regarding the existing evidence for clinical outcomes and failure rates of OCA transplantation in the knee joint was performed using the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, PubMed, and MEDLINE from studies published between 1980 and 2017. Inclusion criteria were as follows: clinical outcomes and failure rates of OCAs for the treatment of chondral defects in the knee joint, English language, mean follow-up of 2 years and minimum follow-up of 18 months, minimum study size of 20 patients, and human studies. The methodological quality of each study was assessed using a modified version of the Coleman methodology score.

RESULTS

The systematic search identified 19 studies with a total of 1036 patients. The mean 5-year survival rate across the studies included in this review was 86.7% (range, 64.1%-100.0%), while the mean 10-year survival rate was 78.7% (range, 39.0%-93.0%). The mean survival rate was 72.8% at 15 years (range, 55.8%-84.0%) and 67.5% at 20 years (range, 66.0%-69.0%). The weighted mean patient age was 31.5 years (range, 10-82 years), and the weighted mean follow-up was 8.7 years (range, 2-32 years). The following outcome measures showed significant improvement from preoperatively to postoperatively: d'Aubigné-Postel, International Knee Documentation Committee, Knee Society function, and Lysholm scores. The weighted mean reoperation rate was 30.2% (range, 0%-63%). The weighted mean failure rate was 18.2% (range, 0%-31%). Of note, revision cases, patellar lesions, and bipolar lesions demonstrated worse survival rates.

CONCLUSION

Improved patient-reported outcomes can be expected after OCA transplantation, with a survival rate of 78.7% at 10 years. Revision cases, patellar lesions, and bipolar lesions were associated with worse survival rates; therefore, utilization of the most appropriate index cartilage restoration procedure and proper patient selection are key to improving results.

Clinical and MRI Outcomes of Fresh Osteochondral Allograft Transplantation After Failed Cartilage Repair Surgery in the Knee

BACKGROUND

Fresh osteochondral allograft transplantation is an appealing option to address a failed cartilage repair surgical procedure, given the ability to treat large lesions and to address the subchondral osseous changes commonly seen in the revision setting. We hypothesized that osteochondral allograft transplantation after failed cartilage repair would result in low failure rates and improved function and that improved graft incorporation on postoperative magnetic resonance imaging (MRI) would correlate with a superior clinical outcome.

METHODS

A retrospective review of prospectively collected data was used to identify 43 patients treated with fresh osteochondral allograft transplantation after a previous cartilage repair surgical procedure and having a minimum follow-up of 2 years. Clinical outcomes were evaluated using the Short Form-36 (SF-36) score, International Knee Documentation Committee (IKDC) Subjective Knee Score, Marx Activity Scale, Knee Outcome Survey-Activities of Daily Living (KOS-ADL) Questionnaire, Cincinnati Sports Activity Score, and Cincinnati Overall Symptom Assessment. Postoperative MRI scans were obtained at a mean time of 19.7 months and were independently reviewed by a musculoskeletal radiologist using the Osteochondral Allograft MRI Scoring System (OCAMRISS).

RESULTS

At a mean 3.5-year follow-up after osteochondral allograft transplantation, significant improvements (p < 0.05) in SF-36 Physical Function, SF-36 Pain, KOS-ADL, IKDC Subjective Knee Score, and Cincinnati Overall Symptom Assessment were seen. Over 90% of grafts remained in situ at the time of the latest follow-up, although 17 knees (40%) underwent reoperation, the majority for arthroscopic debridement or manipulation for stiffness. Body mass index (BMI) of >30 kg/m was associated with worse clinical outcomes. The mean total OCAMRISS score demonstrated poorer allograft integration in patients with graft failure, but the total score did not meaningfully correlate with clinical outcome scores. However, better individual articular cartilage appearance and osseous integration subscores were associated with better clinical outcome scores.

CONCLUSIONS

Significant improvements in pain and function were seen following fresh osteochondral allograft transplantation after failed cartilage repair, with an overall graft survival rate of >90%. Patients with greater bone and cartilage incorporation on MRI had superior clinical outcomes, although persistent osseous edema was frequently seen. We concluded that osteochondral allograft transplantation is an effective salvage treatment after failed cartilage repair and recommend further evaluation of techniques to optimize graft integration.

LEVEL OF EVIDENCE

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

Learning From Failure in Cartilage Repair Surgery: An Analysis of the Mode of Failure of Primary Procedures in Consecutive Cases at a Tertiary Referral Center

Background:

As the number of cartilage restoration procedures is increasing, so is the number of revision procedures. However, there remains limited information on the reasons for failure of primary cartilage restoration procedures.

Purpose:

To determine the common modes of failure in primary cartilage restoration procedures to improve surgical decision making and patient outcomes.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patients who presented for revision after failed cartilage repair surgery were evaluated for factors contributing to failure of the primary procedure. All revision cases performed by a single surgeon at a tertiary center for failed cartilage restoration over a 6-year time frame were identified. In all cases, the medical records, preoperative radiographs, and magnetic resonance imaging scans were reviewed by 2 experienced cartilage surgeons. The cause for failure was categorized as malalignment, meniscal deficiency, graft or biologic failure, or instability. Univariate and descriptive statistics regarding patient demographics, index procedure, lesion location and size, and mechanism of failure were analyzed.

Results:

A total of 59 cases in 53 patients (32 male, 21 female) met the inclusion criteria. The mean patient age at the time of revision was 27.6 years, and the mean body mass index was 28.4 kg/m². Failed index surgical procedures included 35 microfractures (59%), 12 osteochondral allograft transplantations (20%), 10 osteochondral autograft transfers (17%), 2 nonviable osteochondral allografts (3%), and 2 particulated juvenile chondral allografts (3%). The mean lesion size was 4.4 cm². Reasons for failure included 33 cases with untreated malalignment (56%), 16 with graft failure (27%), 11 with untreated meniscal deficiency (19%), and 3 with untreated instability (5%); 4 cases demonstrated multiple reasons for failure.

Conclusion:

The most commonly recognized reason for failure was untreated malalignment. While biologic and graft failures will occur, the majority of failures were attributed to untreated background factors such as malalignment, meniscal deficiency, and instability. The stepwise approach of considering and addressing alignment, meniscal volume, and stability remains essential in cartilage restoration surgery.

Long-term Follow-up of Revision Osteochondral Allograft Transplantation of the Ankle

BACKGROUND

Osteochondral allograft (OCA) transplantation is a useful alternative for treatment of posttraumatic ankle arthritis in young patients but has a relatively high failure rate and further procedures are often required. The purpose of this study was to evaluate outcomes of patients who underwent revision OCA transplantation of the ankle after failed primary OCA transplantation.

METHODS

Twenty patients underwent revision OCA transplantation of the ankle between 1988 and 2015. Mean age was 44 years, 55% (11 of 20) were female. The mean time from primary to revision OCA was 3.0 ± 1.7 years. All patients had a minimum follow-up of 2 years. Outcomes included the American Academy of Orthopaedic Surgeons Foot and Ankle Module (AAOS-FAM) and questionnaires evaluating pain and satisfaction. Failure of the revision OCA was defined as a conversion to arthroplasty, arthrodesis, or amputation.

RESULTS

Ten of 20 ankles required further surgery, of which 30% (6 of 20) were considered OCA revision failures (4 arthrodeses, 1 arthroplasty, and 1 amputation). The mean time to failure was 6.7 (range, 0.6-13.1) years. Survivorship of the revision OCA was 84% at 5 years and 65% at 10 years. The 14 patients with grafts remaining in situ had an average follow-up of 10.3 years; mean AAOS-FAM Core Score was 70.5 (range, 42.3-99). Of the patients who answered the follow-up questions, 4 of 7 reported moderate to severe pain, and 5 of 12 were satisfied with the results of the procedure.

CONCLUSION

Although the results of revision ankle OCA transplantation are not inferior to primary OCA transplantation, the high rates of persistent pain, further surgery, and graft failure suggest that the indications for OCA as a revision procedure should be carefully evaluated, with proper patient selection. Considering the treatment alternatives, revising a failed OCA transplantation can be a useful treatment option, especially for young and active patients who wish to avoid arthrodesis or arthroplasty.

LEVEL OF EVIDENCE

Level IV, case series.

Treatment of Failed Articular Cartilage Reconstructive Procedures of the Knee: A Systematic Review

Background

Symptomatic articular cartilage lesions of the knee are common and are being treated surgically with increasing frequency. While many studies have reported outcomes following a variety of cartilage restoration procedures, few have investigated outcomes of revision surgery after a failed attempt at cartilage repair or reconstruction.

Purpose

To investigate outcomes of revision cartilage restoration procedures for symptomatic articular cartilage lesions of the knee following a previously failed cartilage reconstructive procedure.

Study Design

Systematic review; Level of evidence, 4.

Methods

A literature search was performed by use of the PubMed, EMBASE, and MEDLINE/Ovid databases for relevant articles published between 1975 and 2017 that evaluated patients undergoing revision cartilage restoration procedure(s) and reported outcomes using validated outcome measures. For studies meeting inclusion criteria, relevant information was extracted.

Results

Ten studies met the inclusion criteria. Lesions most commonly occurred in the medial femoral condyle (MFC) (52.8%), with marrow stimulation techniques (MST) the index procedure most frequently performed (70.7%). Three studies demonstrated inferior outcomes of autologous chondrocyte implantation (ACI) following a previous failed cartilage procedure compared with primary ACI. One study comparing osteochondral allograft (OCA) transplant following failed microfracture (MFX) with primary OCA transplant demonstrated similar clinical outcomes and graft survival at midterm follow-up. No studies reported outcomes following osteochondral autograft transfer (OAT) or newer techniques.

Conclusion

This systematic review of the literature reporting outcomes following revision articular cartilage restoration procedures (most commonly involving the MFC) demonstrated a high proportion of patients who underwent prior MST. Evidence is sufficient to suggest that caution should be taken in performing ACI in the setting of prior MST, likely secondary to subchondral bone compromise. OCA appears to be a good revision treatment option even if the subchondral bone has been violated from prior surgery or fracture.

Commercial Products for Osteochondral Tissue Repair and Regeneration

The osteochondral tissue represents a complex structure composed of four interconnected structures, namely hyaline cartilage, a thin layer of calcified cartilage, subchondral bone, and cancellous bone. Due to the several difficulties associated with its repair and regeneration, researchers have developed several studies aiming to restore the native tissue, some of which had led to tissue-engineered commercial products. In this sense, this chapter discusses the good manufacturing practices, regulatory medical conditions and challenges on clinical translations that should be fulfilled regarding the safety and efficacy of the new commercialized products. Furthermore, we review the current osteochondral products that are currently being marketed and applied in the clinical setting, emphasizing the advantages and difficulties of each one.

Condyle-Specific Matching Does Not Improve Midterm Clinical Outcomes of Osteochondral Allograft Transplantation in the Knee

BACKGROUND

Condyle-specific matching for osteochondral allograft transplantation (OCA) pairs donor and recipient condyles in an attempt to minimize articular incongruity. While the majority of cartilage defects are located on the medial femoral condyle, lateral femoral condyles are more commonly available as a graft source. The purpose of this study was to compare the clinical outcomes of patients treated with non-orthotopic (lateral-to-medial condyle or medial-to-lateral condyle) OCA with those treated with traditional orthotopic (medial-to-medial condyle or lateral-to-lateral condyle) OCA. We hypothesized that clinical outcomes would be similar between groups at midterm follow-up.

METHODS

A retrospective review of prospectively collected data on patients treated with OCA from 2000 to 2014 was conducted. Seventy-seven patients with a full-thickness cartilage defect of a femoral condyle were treated with either orthotopic (n = 50) or non-orthotopic (n = 27) OCA. A minimum follow-up of 2 years was required for analysis. Patients in each group were matched according to sex, age, and total chondral defect size. Reoperations and patient responses to validated outcome measures were reviewed. Failure was defined as any revision cartilage procedure or conversion to knee arthroplasty.

RESULTS

The mean duration of follow-up was 4.0 years (range, 2 to 16 years). The orthotopic and non-orthotopic OCA groups were comparable in terms of demographics, the mean number of prior ipsilateral knee operations, and the percentage of concomitant procedures at baseline. Reoperation (p = 0.427) and failure (p = 0.917) rates did not differ significantly between groups. Both groups demonstrated significant increases in the Short Form-36 (SF-36) physical functioning and pain, International Knee Documentation Committee (IKDC), and Knee Outcome Survey-Activities of Daily Living (KOS-ADL) scores compared with baseline (p < 0.004). Outcome scores (baseline and postoperative) and change scores did not differ significantly between groups.

CONCLUSIONS

Clinical outcomes do not differ between patients treated with orthotopic OCA and those treated with non-orthotopic OCA, suggesting that condyle-specific matching may not be necessary.

LEVEL OF EVIDENCE

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

How to Manage a Failed Cartilage Repair: A Systematic Literature Review

Purpose  The aims of this paper are to report the rate and risk factors for the failure of the most common cartilage repair technique, and analyze the most important factors that could influence the choice of a specific surgical treatment to revise a failed cartilage repair.

Methods  A review of the literature was performed focusing on failed cartilage repair and related treatments. Two of the authors independently screened articles. Conflicts about the inclusion of a paper was resolved by further evaluation by the senior author. Review articles, articles written in languages different from/other than English, case reports, and papers that did not evaluate the outcomes of interest were excluded. Full-text version of each included paper was obtained and relevant data were extracted and collected in a database.

Results  At the end of the screening process, 31 articles were included. Microfractures and mosaicplasty showed a nonnegligible failure rate at short- and midterm. Better results, especially in terms of time to failure or revision, were reported with the use of autologous chondrocyte implantation (ACI) and osteochondral allograft (OCA) transplantation. Regarding the treatment of failed cartilage repair, the use of OCA transplantation in patients with previous failed cartilage repair may be a safe option. The revision of failed OCA transplantation with further OCA seems to have a greater failure rate. Patients with previous failed ACI or matrix-induced autologous chondrocyte implantation (MACI) who underwent further MACI or ACI reported acceptable results. Otherwise, ACI in patients with history of previous subchondral marrow stimulation (SMS) demonstrated a greater failure rate.

Conclusion  From the analysis of the literature, OCA transplantation seems to be the most reliable treatment of a failed SMS. ACI or MACI showed acceptable results in patients with previously failed MACI or ACI.

Level of Evidence  Level IV, systematic review of level I-IV studies.

Fresh osteochondral allotransplants: Outcomes, failures and future developments

Osteochondral allografts are used to treat many different conditions as acute traumatic large-sized lesions, degenerative osteoarthritis, osteochondritis dissecans, avascular necrosis or in case of failure of previous procedures particularly in young patients for whom primary prosthesis is not desirable. Fresh allografts present the advantage of having mature viable hyaline cartilage, not causing donor morbidity, allowing the restoration of even large defects in a single surgical session. Conversely, they could account for risks of disease transmission, immunologic reactions, and for limited availability. The present review aimed to analyze published studies of the last decade in which patients received fresh osteochondral allografts by dividing them for knee or ankle regenerative purposes. We wish to report the observed failure rates and particularly to collect any other reported side effect or outcome for identifying major problems and limits linked to the procedure and for delineating possible future researches and approaches. The overall success rates resulted ranging from 5.3% to 48.3% in the ankle at a mean follow up of 3.3 years and from 0% to 85.7% in the knee at a mean follow up of 7.1 years. Among other outcomes, occurrence or progression of arthritis, osteolysis, graft instability, fractures, nonunions, edema and infections were recorded. Overall, the lack of well designed randomized and controlled clinical trials, of immunological determination of the anti-donor antibodies development and of local and systemic biomarkers to detect reaction to the graft seems to be the major drawback. Improvements in these limiting factors might be desirable in order to enhance the clinical scenario of a well-established and successful procedure to give, especially for young patients, a real regeneration of the joint.

Joint Preservation Techniques in Orthopaedic Surgery

CONTEXT

With increasing life expectancy, there is growing demand for preservation of native articular cartilage to delay joint arthroplasties, especially in younger, active patients. Damage to the hyaline cartilage of a joint has a limited intrinsic capacity to heal. This can lead to accelerated degeneration of the joint and early-onset osteoarthritis. Treatment in the past was limited, however, and surgical treatment options continue to evolve that may allow restoration of the natural biology of the articular cartilage. This article reviews the most current literature with regard to indications, techniques, and outcomes of these restorative procedures.

EVIDENCE ACQUISITION

MEDLINE and PubMed searches relevant to the topic were performed for articles published between 1995 and 2016. Older articles were used for historical reference. This paper places emphasis on evidence published within the past 5 years.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 4.

RESULTS

Autologous chondrocyte implantation and osteochondral allografts (OCAs) for the treatment of articular cartilage injury allow restoration of hyaline cartilage to the joint surface, which is advantageous over options such as microfracture, which heal with less favorable fibrocartilage. Studies show that these techniques are useful for larger chondral defects where there is no alternative. Additionally, meniscal transplantation can be a valuable isolated or adjunctive procedure to prolong the health of the articular surface.

CONCLUSION

Newer techniques such as autologous chondrocyte implantation and OCAs may safely produce encouraging outcomes in joint preservation.

Allografts: Osteochondral, Shell, and Paste

There is an increasing need for articular cartilage restoration procedures. Hyaline cartilage lacks intrinsic healing capacity. Persistent osteochondral defects can lead to early and rapid degenerative changes. Microfracture and autologous chondrocyte implantation provide reasonable outcomes for smaller defects without bone loss. However, these techniques have limited effectiveness for lesions greater than 4 cm² or with significant bony involvement. Ostochondral allografts provide an option for these lesions. This article reviews osteochondral allografts for articular defects. Emerging options provide different approaches to difficult cartilage defects. We discuss current screening, procurement, and storage methods, surgical techniques, outcomes, and bacterial/viral transmission.

Osteochondral Allograft Transplantation of the Knee: Analysis of Failures at 5 Years

BACKGROUND

Osteochondral allograft transplantation (OAT) is being performed with increasing frequency, and the need for reoperations is not uncommon.

PURPOSE

To quantify survival for OAT and report findings at reoperations.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A review of prospectively collected data of 224 consecutive patients who underwent OAT by a single surgeon with a minimum follow-up of 2 years was conducted. The reoperation rate, timing of reoperation, procedure performed, and findings at surgery were reviewed. Failure was defined by revision OAT, conversion to knee arthroplasty, or gross appearance of graft failure at second-look arthroscopic surgery.

RESULTS

A total of 180 patients (mean [±SD] age, 32.7 ± 10.4 years; 52% male) who underwent OAT with a mean follow-up of 5.0 ± 2.7 years met the inclusion criteria (80% follow-up). Of these, 172 patients (96%) underwent a mean of 2.5 ± 1.7 prior surgical procedures on the ipsilateral knee before OAT. Forty-eight percent of OAT procedures were isolated, while 52% were performed with concomitant procedures including meniscus allograft transplantation (MAT) in 65 (36%). Sixty-six patients (37%) underwent a reoperation at a mean of 2.5 ± 2.5 years, with 32% (21/66) undergoing additional reoperations (range, 1-3). Arthroscopic debridement was performed in 91% of patients with initial reoperations, with 83% showing evidence of an intact graft; of these, 9 ultimately progressed to failure at a mean of 4.1 ± 1.9 years. A total of 24 patients (13%) were considered failures at a mean of 3.6 ± 2.6 years after the index OAT procedure because of revision OAT (n = 7), conversion to arthroplasty (n= 12), or appearance of a poorly incorporated allograft at arthroscopic surgery (n = 5). The number of previous surgical procedures was independently predictive of reoperations and failure; body mass index was independently predictive of failure. Excluding the failed patients, statistically and clinically significant improvements were found in the Lysholm score, International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, and Short Form-12 physical component summary at final follow-up ( P < .001 for all), with inferior outcomes (albeit overall improved) in patients who underwent a reoperation.

CONCLUSION

In this series, there was a 37% reoperation rate and an 87% allograft survival rate at a mean of 5 years after OAT. The number of previous ipsilateral knee surgical procedures was predictive of reoperations and failure. Of the patients who underwent arthroscopic debridement with an intact graft at the time of arthroscopic surgery, 82% experienced significantly improved outcomes, while 18% ultimately progressed to failure. This information can be used to counsel patients on the implications of a reoperation after OAT.

A Comparison of the Outcomes for Cartilage Defects of the Knee Treated With Biologic Resurfacing Versus Focal Metallic Implants

PURPOSE

To compare the results of focal metallic resurfacing with biologic procedures in patients more than 35 years of age with isolated, full thickness defects of the femoral condyle.

METHODS

A total of 61 patients met the selection criteria resulting in 30 patients treated with biological procedures, including debridement, microfracture, osteochondral autograft transplantation, osteochondral allograft, and autologous chondrocyte implantation (BIO group), and 32 patients treated with focal metallic resurfacing (CAP group). The BIO and CAP groups were matched according to treatment location, defect grade and size, and age profile. Outcomes included Western Ontario and McMaster Osteoarthritis Index (WOMAC), Short Form-12, and satisfaction. The primary combination endpoint was determined as a 20% improvement (minimum clinically important difference-20) on WOMAC pain and function at 2 years and no additional index lesion-related surgical intervention. Safety and effectiveness were also reported.

RESULTS

Thirty patients in the BIO group (mean age of 44.6, range 35-64) had an average follow-up of 2.6 years and 32 patients in the CAP group (mean age 47.9, range 37-68) were followed for 2.0 years. Fifty-three percent in the BIO group and 75% in the CAP group achieved success per the endpoint definition. The mean total WOMAC score improved significantly for both groups (BIO: 57-78; P < .001) (CAP: 41-86; P < .001). The physical component score (Short Form-12 PCS) improved significantly in the CAP group only (30-36.4; P < .001). Good to excellent patient satisfaction was achieved by 80% in BIO and 91% in CAP. There were 4 secondary procedures on the index lesion in the BIO group and 2 in the CAP group.

CONCLUSIONS

Careful patient selection can achieve high satisfaction rates with both biological and focal metal resurfacing procedures for the treatment of isolated focal chondral lesions of the femoral condyle in the knee. Focal metallic resurfacing results in similar clinical outcomes and provides excellent success rates at short-term follow-up.

LEVEL OF EVIDENCE

Level III comparative study.

Osteochondral Allograft Transplantation in Patients With Osteochondritis Dissecans of the Knee

BACKGROUND

Osteochondritis dissecans (OCD) of the knee can be difficult to treat. Cartilage restoration techniques are often indicated when the lesion or fragment cannot be salvaged and the patient remains symptomatic. Fresh osteochondral allograft (OCA) transplantation can restore both bone and cartilage defects characteristic of OCD.

HYPOTHESIS

We hypothesized that osteochondral allografting is a successful method for treating OCD of the knee.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This study comprised 135 patients (149 knees) who underwent OCA for OCD of the knee (type III or IV) between 1997 and 2013 and had a minimum follow-up of 2 years. The median age was 21 years (range, 12-55 years) and 75.8% of the patients were male. The mean allograft size was 7.3 cm² (range, 2.2-25 cm²). Evaluation included the following: frequency and type of reoperations; modified Merle d'Aubigné and Postel (18-point) scale; International Knee Documentation Committee (IKDC) pain, function, and total scores; and Knee Society function (KS-F) and knee (KS-K) scores. Clinical failure was defined as revision OCA or conversion to arthroplasty. Graft survivorship was determined.

RESULTS

The median follow-up time was 6.3 years (range, 1.9-16.8 years) and 62% of participants had more than 5-year follow-up. Thirty-four of 149 knees (23%) had reoperations, of which 12 (8%) were classified as allograft failures (7 OCA revisions, 3 unicompartmental knee arthroplasties, and 2 total knee arthroplasties). OCA survivorship was 95% at 5 years and 93% at 10 years. Of the 137 knees whose grafts were still in situ at the latest follow-up, the mean modified Merle d'Aubigné and Postel (18-point) score was 16.8; IKDC pain, function, and total scores were 2.1, 8.1, and 82.3; and KS-F and KS-K scores were 95.7 and 94.3, respectively. The majority of patients (95%) reported being satisfied with the outcome of their procedure.

CONCLUSION

OCA transplantation was an effective treatment for OCD of the knee, with a low rate of graft failure, significant improvement in pain and function scores, and high patient satisfaction.

Osteochondral allograft

Over the past decade, osteochondral allograft transplantation has soared in popularity. Advances in storage techniques have demonstrated improved chondrocyte viability at longer intervals and allowed for potential of increased graft availability. Recent studies have stratified outcomes according to location and etiology of the chondral or osteochondral defect. Unipolar lesions generally have favorable outcomes with promising 10-year survival rates. Though those undergoing osteochondral allograft transplantation often require reoperation, patient satisfaction remains high.

Osteochondral allograft transplantation in cartilage repair: Graft storage paradigm, translational models, and clinical applications

The treatment of articular cartilage injury and disease has become an increasingly relevant part of orthopaedic care. Articular cartilage transplantation, in the form of osteochondral allografting, is one of the most established techniques for restoration of articular cartilage. Our research efforts over the last two decades have supported the transformation of this procedure from experimental "niche" status to a cornerstone of orthopaedic practice. In this Kappa Delta paper, we describe our translational and clinical science contributions to this transformation: (1) to enhance the ability of tissue banks to process and deliver viable tissue to surgeons and patients, (2) to improve the biological understanding of in vivo cartilage and bone remodeling following osteochondral allograft (OCA) transplantation in an animal model system, (3) to define effective surgical techniques and pitfalls, and (4) to identify and clarify clinical indications and outcomes. The combination of coordinated basic and clinical studies is part of our continuing comprehensive academic OCA transplant program. Taken together, the results have led to the current standards for OCA processing and storage prior to implantation and also novel observations and mechanisms of the biological and clinical behavior of OCA transplants in vivo. Thus, OCA transplantation is now a successful and increasingly available treatment for patients with disabling osteoarticular cartilage pathology.

Combined osteochondral allograft and meniscal allograft transplantation: a survivorship analysis

INTRODUCTION

The efficacy of meniscal allograft transplantation (MAT) and osteochondral allografting (OCA) as individual treatment modalities for select applications is well established. MAT and OCA are considered symbiotic procedures due to a complementary spectrum of indications and reciprocal contraindications. However, few outcomes of concomitant MAT and OCA have been reported. This study is a retrospective review of patients who received simultaneous MAT and OCA between 1983 and 2011.

METHODS

Forty-eight (twenty-nine male: nineteen female) patients with a median age of 35.8 years (15-66) received combined MAT and OCA procedures between 1983 and 2011. Forty-three patients had received previous surgery with a median of 3 procedures (1-11 procedures). The underlying diagnosis was trauma (tibial plateau fracture) in 33 % with osteoarthritis predominating in 54.2 % of cases. Thirty-one patients received a lateral meniscus, 16 received a medial meniscus and one patient received bilateral MAT. The median number of OCAs was two per patient (1-5 grafts), with a median graft area of 15 cm(2) (0.7-41 cm(2)). There were 21 unipolar, 24 bipolar (tibiofemoral) and three multifocal lesions. Thirty-six MATs constituted a compound tibial plateau OCA with native meniscus attached. At follow-up, failure was defined as any procedure resulting in removal or revision of one or more of the grafts. Patients completed the modified Merle d'Aubigné and Postel (18-point) scale, Knee Society Function (KS-F) score, and subjective International Knee Documentation Committee (IKDC) scores. Patient satisfaction was also captured.

RESULTS

Twenty-six of 48 patients (54.2 %) required reoperation, but only 11 patients (22.9 %) were noted to have failed (10 MAT and 11 OCA). The mean time to failure was 3.2 years (95 % CI 1.5-4.9 years) and 2.7 years (95 % CI 1.3-4.2 years) for MAT and OCA, respectively. The 5-year survivorship was 78 and 73 % for MAT and OCA respectively, and 69 and 68 % at 10 years. Six of the failures were in the OA cases and one was an OCD lesion where bipolar grafts were utilized. The OCD case underwent a revision OCA and remains intact. The others were converted to knee arthroplasty. One case failed due to early deep infection, ultimately requiring arthrodesis. Of those with grafts still intact, the mean clinical follow-up was 6.8 years (1.7-17.1 years). Statistically significant improvements in all outcome scores were noted between baseline and the latest follow-up. In total, 90 % of those responding would have the surgery again and 78 % were either extremely satisfied or satisfied with the outcome.

CONCLUSION

The overall success rate of concomitant MAT and OCA was comparable with reported results for either procedure in isolation. A trend towards  a worse outcome was observed with bipolar tibiofemoral grafts in the setting of OA. Comparatively better results in less advanced, unipolar disease could suggest a benefit to early intervention that might merit a lower treatment threshold for combined MAT and OCA.

LEVEL OF EVIDENCE

IV.

Fresh osteochondral allograft transplantation for bipolar reciprocal osteochondral lesions of the knee

BACKGROUND

Osteochondral allograft (OCA) transplantation is an effective treatment option for chondral and osteochondral defects of the knee.

HYPOTHESIS

Patients treated with OCAs for reciprocal bipolar lesions of the knee would demonstrate significant clinical improvement.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Between 1983 and 2010, OCAs were implanted for bipolar chondral lesions in 46 patients (48 knees). The 21 male and 25 female patients averaged 40 years of age (range, 15-66 years). Thirty-four lesions were tibiofemoral, and 14 were patellofemoral. Forty-two knees (88%) had undergone a mean of 3.4 previous surgeries (range, 1-8). The mean allograft area was 19.2 cm(2). Clinical evaluation included the modified Merle d'Aubigné-Postel (18-point), International Knee Documentation Committee (IKDC) pain and function, and Knee Society function (KS-F) scores. Further surgeries on the operative joint were documented.

RESULTS

Survivorship of the bipolar OCA was 64.1% at 5 years. Thirty knees underwent further surgery; 22 knees (46%) were considered failures (3 OCA revisions, 14 total knee arthroplasties, 2 unicondylar arthroplasties, 2 arthrodeses, and 1 patellectomy). Among patients whose OCA was still in situ at follow-up, the mean follow-up was 7 years (range, 2.0-19.7 years). The mean 18-point score improved from 12.1 to 16.1; 88% (23/26 knees) of surviving allografts scored ≥15. The mean IKDC pain score improved from 7.5 to 4.7, and the mean IKDC function score improved from 3.4 to 7.0. The mean KS-F score improved from 70.5 to 84.1.

CONCLUSION

Osteochondral allograft transplantation is a useful salvage treatment option for reciprocal bipolar cartilage lesions of the knee. High reoperation and failure rates were observed, but patients with surviving allografts showed significant clinical improvement.