Osteochondral Transplantation Research Articles

Fresh osteochondral allograft transplantation for knee full-thickness articular cartilage lesions using femoral head of living donors: short-term results.

Fresh osteochondral allograft transplantation is a good treatment option of cartilage defects. However, this treatment option is not available in all countries due to limited graft availability and tissue banks limitations. The purpose of this study is to assess the short term functional and imaging outcomes of fresh osteochondral allograft transplantation in the knee using the femoral head of living donors. Fresh osteochondral allografts from the femoral heads of living donors is a valid graft source for management of distal Femur cartilage defects. This technique can improve functional knee scores with good radiological outcomes. Prospective case series. Fifteen patients with full thickness cartilage defects of the distal femur underwent osteochondral allograft transplantation from the femoral heads of living donors. Grafts were transplanted by both shell and multiple dowels techniques. The average follow up duration was 18.3 months (range, 12-25 months). Patients were evaluated by Lysholm and International Knee Documentation Committee (IKDC) scores, radiography and MR imaging using Osteochondral Allograft MRI Scoring System (OCAMRISS). There was a statistically significant improvement (P < 0.001) in both Lysholm and IKDC average scores at 6 months and 12 months postoperative. Postoperative MRI was done at an average 6.8 months (range, 5-11 months) postoperative. The mean total OCAMRISS score was 3.4 (range, 1-7). A second look arthroscopy was done in four patients and showed intact articular cartilage in all three patients. Femoral head of living donors is a valid new source for fresh osteochondral allograft transplantation of knee osteochondral lesions. Short term results showed improvement in clinical assessment scores. Follow up imaging showed graft incorporation and good MRI scores.

The Condition of the Meniscus and Cartilage of the Injured Knee on Preoperative Magnetic Resonance Imaging Is a Prognostic Factor Affecting Postoperative Outcomes Following Knee Cartilage Restoration Surgery

PurposeTo evaluate the relationship between preoperative whole-joint imaging evaluation of the knee with patient reported outcome measures after cartilage restoration surgery (mosaicplasty, osteochondral allograft transplantation (OCA), matrix autologous chondrocyte implantation (MACI)). MethodsWe retrospectively evaluated patients who underwent knee articular cartilage restoration at our institution from 2014 to 2020. The patients’ knee MRI was evaluated with the whole joint magnetic resonance imaging score (WORMS) and semi-quantitative synovial inflammation imaging biomarkers of the preoperative MRI. To assess patient-reported outcome (PRO) score, Lysholm score and Knee Osteoarthritis and Injury Outcome Score (KOOS) were completed at minimum 2 years follow-up. Statistical analysis was performed using Spearman rank test to obtain correlation values for WORMS score and PRO score for each survey. ResultsThere were 40 patients who were enrolled in this study. The average age at baseline was 34.5 years. The average BMI was 28.2 kg/m2 and 26 of 40 were men (range, 20-58 years). The maximum preoperative WORMS score was significantly correlated with the post-operative Lysholm score (r = -0.52, p=0.0013). The WORMS Meniscus and Cartilage sub-scales were significantly correlated with the Lysholm score (r = -0.36, p=0.024 and r = -0.37, p=0.021 respectively). The maximum WORMS score was significantly correlated with the KOOS Daily living and Sports/rec sub-scores (r= -0.47, p=0.0023 and r = -0.42, p=0.0077, respectively). Semi-quantitative synovial inflammation imaging biomarkers were not significantly correlated with PRO scores. ConclusionIncreasing preoperative degenerative change in the knee, as evidenced by a higher WORMS on preoperative MRI, was associated with inferior patient-reported outcomes at a minimum of 2 years after cartilage restoration surgery (mosaicplasty, OCA, MACI). Semi-quantitative scoring of the whole joint on preoperative MRI may allow for improved counseling regarding expected benefit for patients after cartilage restoration surgery.

Outcomes of Osteochondral Allograft Transplantation for Femoral Head Cartilage Lesions: Minimum 2-Year Follow-Up

BackgroundThe surgical management of large osteochondral lesions of the femoral head in young, active patients remains controversial. Fresh osteochondral allograft (OCA) transplantation can be a highly effective treatment for these lesions in some patients. This study investigated survivorship as well as clinical and radiographic outcomes after fresh OCA transplantation at a minimum 2-year follow-up (mean, 6.6 years; range, 0.6 to 13.7 years). MethodsA retrospective review of 29 patients who underwent plug OCA transplantation for focal femoral head osteochondral lesions between 2008 and 2021 was performed. Patients were assessed clinically using the modified Harris Hip score (mHHS) preoperatively and at each follow-up visit. Postoperative radiographs were evaluated for graft integrity and osteoarthritis severity. Kaplan-Meier survivorship analyses with 95% confidence intervals (CIs) were performed for the endpoint of conversion to total hip arthroplasty (THA). ResultsOverall graft survivorship for included patients was 78.4% (95% CI: 62.9 to 93.9) and 62.7% (95% CI: 39.6 to 85.8) at 5 and 10 years, respectively. There were ten patients (34.5%) who underwent conversion to THA. There was a significant difference using the log-rank test between survival for patients who had a preoperative diagnosis of osteonecrosis (ON) versus those who had other diagnoses (P = .002). The ten-year survival for those who had ON was 41.8% (95% CI: 4.8 to 78.8), and the ten-year survival for diagnoses other than ON was 85.7% (95% CI: 59.8 to 100). The mean mHHS score improved significantly (P < .001) from 48.9 (19 to 84) preoperatively to 77.4 (35 to 100) at the final follow-up. There were twenty patients (69.0%) who had mHHS ≥ 70 at the latest follow-up. Arthritic progression, indicated by an increase in the Kellgren and Lawrence grade, occurred in 7 hips (26.9%). ConclusionsAn OCA transplantation is a viable treatment option for osteochondral defects of the femoral head in young, active patients who have minimal preexisting joint deformity. It may delay the progression of arthritis and the need for THA. Patients who had a preoperative diagnosis of ON had worse clinical outcomes than those who had other diagnoses.

Outcomes Following the Use of Extracellular Matrix Cartilage Allograft for the Management of Osteochondral Lesions of the Talus: A Systematic Review.

Extracellular matrix cartilage allograft (EMCA) is a novel biological strategy utilized to augment the repair of osteochondral lesions of the talus (OLTs). However, there is no consensus on the precise role and outcomes following its use in the treatment of OLTs. The purpose of this systematic review was to evaluate the clinical and radiological outcomes following the use of EMCA for the treatment of OLT.During July 2023, the PubMed, Embase, and Cochrane Library databases were systematically reviewed to identify clinical studies examining outcomes following EMCA for the management of OLTs.In total, 162 patients (162 ankles) across five studies received EMCA as part of their surgical procedure at a weighted mean follow-up time of 23.8±4.2 months. Across all five studies, there were improvements in subjective clinical outcomes following the use of EMCA, regardless of the clinical scoring tool utilized. Two studies demonstrated superior postoperative magnetic resonance observation of cartilage repair tissue (MOCART) scores in the EMCA cohort compared to the bone marrow stimulation (BMS) cohort alone.In the EMCA-BMS cohort, there were seven complications (9%) and three failures (4.1%). In the autologous osteochondral transplantation (AOT) cohort, there were 10 complications (38.5%), zero failures, and six secondary surgical procedures (23.1%). In the EMCA alone cohort, there were zero complications and three failures (4.3%), all of which underwent an unspecified revision procedure. This current systematic review demonstrated improvements in both clinical and radiological outcomes following the use of EMCA for the treatment of OLTs.Further prospective comparative studies with longer follow-up times are warranted to determine the precise role of EMCA in the management of OLT.

Outcomes After Single-Stage Anatomic Multiligament Knee Reconstruction With Early Range of Motion in Adolescents.

Multiligament knee injuries (MLKI), rare in adolescents, are challenging injuries that require complex surgical reconstruction. Historically, nonanatomic reconstructions have been associated with prolonged immobilization and failure to restore normal knee biomechanics, resulting in arthrofibrosis and high rates of graft failure. To describe the clinical and patient-reported outcomes (PROs) for adolescent patients treated with single-stage anatomic multiligament knee reconstruction. Case series; Level of evidence, 4. A single-center retrospective study was performed of patients ≤18 years old who underwent reconstruction of MLKIs by a single surgeon between 2014 and 2019 using a single-stage anatomic technique, with protected weightbearing and early range of motion. Complications were defined as infection, arthrofibrosis, deep vein thrombosis (DVT) or pulmonary embolus, and secondary surgery. PROs, including the pediatric version of the International Knee Documentation Committee (Pedi-IKDC) and the Tegner activity score, were obtained at a minimum of 2 years postoperatively. Included were 30 patients (21 male, 9 female; mean age, 15.4 years). The most common ligamentous reconstruction types were anterior cruciate ligament (ACL) + fibular collateral ligament (12 patients; 40%) and ACL + medial collateral ligament (9 patients; 30%). Three patients (10%) had secondary surgeries, including irrigation and debridement of a granuloma, a staged osteochondral allograft transplantation to a lateral femoral condyle impaction fracture, and repair of a medial meniscal tear and lateral femoral condyle fracture associated with new injuries 2 years after ACL + fibular collateral ligament reconstruction. Two patients (7%) developed arthrofibrosis and 1 patient (3%) developed DVT. PRO scores obtained at a mean of 37 months postoperatively included a mean Pedi-IKDC of 87 (range, 52-92) and a median highest Tegner score at any point postoperatively of 9 (range, 5-10). Of the patients who were athletes before their injury, 70% returned to the same or higher level of sport postoperatively. Reconstruction of MLKI in this series of adolescents with single-stage anatomic techniques and early range of motion resulted in low rates of secondary surgery, few complications, and good knee function as well as PRO scores at mean 3-year follow-up.

Comparable Clinical and Functional Outcomes Between Osteochondral Allograft Transplantation and Autologous Chondrocyte Implantation for Articular Cartilage Lesions in the Patellofemoral Joint at a Mean Follow-up of 5 Years

To assess clinical outcomes and return to sport (RTS) rates among patients who undergo osteochondral allograft (OCA) transplantation and autologous chondrocyte implantation (ACI) or matrix-induced autologous chondrocyte implantation (MACI), for patellofemoral articular cartilage defects. A retrospective review of patients who underwent an OCA or ACI/MACI from 2010 to 2020 was conducted. Patient-reported outcomes collected included visual analog scale for pain/satisfaction, Knee Injury and Osteoarthritis Outcome Score (KOOS), and RTS. The percentage of patients that met the patient acceptable symptom state for KOOS was recorded. Logistic regression was used to identify predictors of worse outcomes. A total of 95 patients were included (78% follow-up) with ACI or MACI performed in 55 cases (57.9%) and OCA in 40 (42.1%). A tibial tubercle osteotomy was the most common concomitant procedure for OCA (66%) and ACI/MACI (98%). Overall, KOOS pain was significantly poorer in OCA than ACI/MACI (74.7, 95% confidence interval 68.1-81.1 vs 83.6, 95% confidence interval 81.3, 88.4, P= .012), whereas the remaining KOOS subscores were nonsignificantly different (all P > .05). Overall, RTS rate was 54%, with no significant difference in return between OCA or ACI/MACI (52% vs 58%, P= .738). There were 26 (27%) reoperations and 5 (5%) graft failures in the entire group. Increasing age was associated with lower satisfaction in OCA and poorer outcomes in ACI/MACI, whereas larger lesion area was associated with lower satisfaction and poorer outcomes in ACI/MACI. Clinical and functional outcomes were similar in patients who underwent OCA or ACI/MACI for patellofemoral articular cartilage defects at a mean follow-up of 5 years. Patients who received OCA had a greater proportion of degenerative cartilage lesions and, among those with trochlear lesions, reported greater pain at final follow-up than their ACI/MACI counterparts. Overall, increasing age and a larger lesion size were associated with worse patient-reported outcomes. Level III, retrospective cohort study.

Sport-specific Differences in Cartilage Treatment.

Articular cartilage defects in the knee are common in athletes who have a variety of loading demands across the knee. Athletes of different sports may have different baseline risk of injury. The most studied sports in terms of prevalence and treatment of cartilage injuries include soccer (football), American football, and basketball. At this time, the authors do not specifically treat patients by their sport; however, return to sports timing may be earlier in sports with fewer demands on the knee based on the rehabilitation protocol. If conservative management is unsuccessful, the authors typically perform a staging arthroscopy with chondroplasty, followed by osteochondral allograft transplantation with possible additional concomitant procedures, such as osteotomies or meniscal transplants. Athletes in a variety of sports and at high levels of competition can successfully return to sports with the appropriate considerations and treatment.

Treatment of Shoulder Cartilage Defects in Athletes.

Articular cartilage defects in the glenohumeral joint may be found in laborers, the elderly, and young athletes, among others. Various factors can contribute to cartilage damage, including prior surgery, trauma, avascular necrosis, inflammatory arthritis, joint instability, and osteoarthritis. There is a wide variety of treatment options, from conservative treatment, injections, and surgical options, including arthroscopic debridement, microfracture, osteochondral autograft transfer, osteochondral graft transplantation, autologous chondrocyte implantation, and the newly emerging techniques such as biologic augmentation. There is a challenge to determine the optimal treatment options, especially for young athletes, due to limited outcomes in the literature. However, there are many options which are viable to address osteochondral defects of the glenohumeral joint.

Cell-Mediated Immune Responses May Play Roles in Osteochondral Allograft Transplantation Osteointegration Failures.

Prolonged and incomplete osteochondral allograft (OCA) osteointegration is consistently cited as a major mechanism for OCA treatment failure. Subrejection immune responses may play roles in this mode of failure. Preimplantation OCA preparation techniques, including subchondral bone drilling, thorough irrigation, and autogenous bone marrow aspirate concentrate saturation, may dampen immune responses and improve OCA osteointegration. This study sought to further characterize potential immune system contributions to OCA transplantation treatment failures by analyzing donor-recipient ABO and Rh-factor mismatches and histological and immunohistochemical assessments of transplanted OCA tissues recovered from revision surgeries. Using a dedicated registry, OCA transplant recipients with documented treatment failures who met inclusion criteria (n = 33) as well as age-, body mass index-, and joint-matched patients with successful outcomes (n = 70) were analyzed to compare matched cohorts of patients with successful versus failed OCA transplantation outcomes. Tissues recovered from 18 failed OCA transplants and portions of 7 nonimplanted OCA controls were further analyzed to provide contributing evidence for potential immune response mechanisms. For patients analyzed, no statistically significant differences in proportions for treatment success versus failure based on mismatches for ABO type, Rh factor, or both were noted. Further, no statistically significant differences in proportions for histological immune response presence or absence based on mismatches for ABO type, Rh factor, or both were noted. Twelve (67%) of the failed OCA tissues contained lymphocyte aggregations in the subchondral bone, which were comprised of combinations of CD3 + , CD4 + , CD8 + , and CD20+ lymphocytes. The mechanisms of failure for these 12 OCA transplants involved insufficient OCA osteointegration. Results of this study suggest that T- and B-cell-mediated subrejection immune responses may play roles in OCA transplant treatment failures independent of donor-recipient blood type mismatch effects.

AUTOLOGOUS OSTEOCHONDRAL TRANSPLANTATION FOR LARGE OSTEOCHONDRAL LESIONS OF THE TALUS IS A VIABLE OPTION IN AN ATHLETIC POPULATION

Autologous osteochondral transplantation (AOT) is an effective treatment for large Osteochondral Lesions of the Talus (OLT), however little is reported on an athletic population, who are likely to place higher demands on the reconstruction. The aim is to report the outcomes of large OLT (&gt;150mm2) within an athletic population. The study population was limited to professional or amateur athletes (Tegner score &gt;6) with an OLT of size 150mm2 or greater. The surgical intervention was AOT with a donor site from the lateral femoral condyle. Clinical outcomes at a minimum of 24 months included Return to Sport, VAS and FAOS Scores. In addition, graft incorporation was evaluated by MRI using MOCART scores at 12 months post-surgery. 38 athletes including 11 professional athletes were assessed. Mean follow-up was 46 months. Mean lesion size was 249mm2. 33 patients returned to sport at their previous level and one did not return to sport (mean return to play 8.2 months). Visual analogue scores improved from 4.53 pre-operatively to 0.63 post-operatively (p=0.002). FAOS Scores improved significantly in all domains (p&lt; 0.001). Two patients developed knee donor site pain, and both had three osteochondral plugs harvested. Univariant analysis demonstrated no association between pre-operative patient or lesion characteristics and ability to return to sport. However, there was a strong correlation between MOCART scores and ability to return to sport (AUC=0.89). Our study suggests that AOT is a viable option in the management of large osteochondral talar defects in an athletic population, with favourable return to sport levels, patient satisfaction, and FAOS/VAS scores. The ability to return to sport is predicated upon good graft incorporation and further research is required to optimise this technique. Our data also suggests that patients should be aware of the increased risk of developing knee donor site pain when three osteochondral plugs are harvested.

Treatment of Medial Patellar Instability With Bipolar Patellofemoral Cartilage Lesions: Staged De-rotational Distal Femoral Osteotomy Followed by Bipolar Osteochondral Allograft Transplantation and Tibial-Tubercle Osteotomy

Background: Patellar instability with symptomatic cartilage lesions in young patients is a challenging problem to treat. The use of osteotomies to correct malalignment and fresh osteochondral allograft transplantation (OCA) to address cartilage lesions and patellofemoral dysplasia is a viable treatment option for carefully selected patients. Indications: The patient is a 22-year-old woman with medial patellar instability caused by iatrogenic distal femoral external rotation and uncontained grade IV patellofemoral lesions. The patient was indicated for OCA because the lesions were too large for an osteochondral autograft transfer system (OATS) and were uncontained and not amenable to autologous chondrocyte implantation. Bipolar OCA also addresses the patient’s patellofemoral dysplasia by restoring a more morphologically normal patellofemoral joint. The external rotation and mild varus deformity are corrected with a biplanar distal femoral osteotomy. Correction of malalignment is necessary prior to OCA transplantation to avoid abnormal graft loading and thereby decrease the risk of graft failure. Technique Description: (1) Diagnostic arthroscopy and fluoroscopic examination under anesthesia. (2) Lateral closing wedge de-rotational distal femoral osteotomy. (3) Bipolar OCA with tibial tubercle osteotomy and removal of hardware. Results: In this case, the patient had significant improvement in her symptoms and had full knee range of motion with a normal gait at 3 months after surgery. Depending on a patient’s preoperative function and the specific pathology, full recovery can take considerably longer. A successful outcome is considered return to activities of daily living without significant pain. Return to higher level athletic activities is significantly more unpredictable. Graft survival of bipolar patellofemoral OCA is variable, and the literature is limited by the small number of procedures performed, but published series range from 60% to 85% at 5 years. Discussion/Conclusion: A successful outcome in these unique, complex cases depends on good patient selection, preoperative planning, and surgical execution. Patellar instability can be reliably treated when the predisposing anatomical factors are appropriately corrected. Bipolar OCA can provide significant improvement in pain and function, but continues to have the highest rate of graft failure compared with other sites within the knee, and should be considered a salvage operation for patients with significant limitations in activities of daily living. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Do reconstructive techniques for osteochondritis dissecans of the skeletally mature knee work?A systematic review and meta-analysis.

Osteochondritis dissecans (OCD) is a common cause of knee pain. Management for adult-onset OCD (AOCD) usually involves surgery. Surgical treatments include palliative, reparative and reconstructive techniques. The aim of this systematic review and meta-analysis is to evaluate the efficacy of reconstructive techniques for the treatment of OCD in skeletally mature knees. A systematic search was carried out on four databases up to November 2023 (Medline, Embase, Cochrane Library, Web of Science). The study was registered on international prospective register of systematic reviews and performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Clinical studies on skeletally mature patients were included, which utilised reconstructive techniques such as autologous chondrocyte implantation (ACI), matrix-induced autologous chondrocyte implantation, osteochondral allograft transplantation surgeryor bone marrow-derived cellular transplantation. Demographical data, patient-reported outcome measures and postoperative complications were recorded. Quantitative outcome measures that were comparable across studies were pooled for meta-analysis. A random effects model was used. Heterogeneity was assessed using the I2 statistic and Cochran's Q test. Statistical significance was set at p < 0.05. Risk of bias was assessed using the risk of bias in non-randomised studies - of interventions tool for nonrandomised studies. Sixteen studies were included with 458 OCD lesions in 432 patients. The average age was 24.9, and 62.6% were male. The mean follow-up time was 61.5 months. At 36 months follow-up, International Knee Documentation Committee (IKDC) subjective, Tegner and EuroQol-visual analogue scale (EQ-VAS) scores improved from 42.4 to 78.6 (standard mean difference [SMD]: 2.47; p < 0.001), 2.27-4.99 (SMD: 2.363; p = 0.002) and 30.4-57.5 (SMD: 2.390; p < 0.001), respectively. Overall complication rate was 8.9%. Smaller OCD lesion sizes resulted in a greater improvement in IKDC subjective (SMD: 2.64 vs. 2.01; p = 0.038), EQ-VAS (SMD: 3.16 vs. 0.95; p = 0.046) and Tegner scores (SMD: 3.13 vs. 1.05; p = 0.007) and had a lower complication rate (p = 0.008). Males showed a larger improvement in IKDC subjective scores than females (SMD: 2.56 vs. 1.56; p = 0.029), while younger patients had a larger improvement in IKDC subjective scores (SMD: 2.71 vs. 2.12; p = 0.045) and fewer complications than older patients (p = 0.003). There were no significant differences between cohorts treated with ACI and those treated with non-ACI reconstructive techniques. Publication bias was not detected (n.s.). Reconstructive techniques used to treat OCD in the skeletally mature knee resulted in significant improvements in clinical and functional outcomes, with a low overall complication rate. Since a younger age leads to a greater improvement in IKDC subjective score and a lower complication rate, surgical intervention should not be delayed, especially in AOCD lesions which are more likely to follow a progressive and unremitting clinical course. Level III.

Knee Cartilage Injuries in Football Players: Clinical Outcomes and Return to Sport After Surgical Treatment: A Systematic Review of the Literature.

To systematically review the literature and analyze clinical outcomes and return-to-sport after surgical management of cartilage injuries in football players. A systematic literature review was performed in August 2023 on PubMed, WebOfScience, and Cochrane Library to collect studies on surgical strategies for cartilage lesions in football players. Methodological quality and risk of bias were assessed with the modified Coleman Methodology score and RoB2 and RoBANS2 tools. Fifteen studies on 409 football players (86% men, 14% women) were included: nine prospective and two retrospective case series, one randomized controlled trial, one prospective comparative study, one case report, and one survey. Bone marrow stimulation (BMS) techniques were the most documented. The lesion size influenced the treatment choice: debridement was used for small lesions (1.1 cm2), BMS, osteochondral autograft transplantation (OAT), matrix-assisted autologous chondrocytes transplantation (MACT), and scaffold-augmented BMS for small/mid-size lesions (2.2-3.0 cm2), and autologous chondrocytes implantation (ACI) for larger lesions (5.8 cm2). The surgical options yielded different results in terms of clinical outcome and return-to-sport, with fastest recovery for debridement and scaffold-augmented BMS. The current evidence is limited with large methodological quality variation (modified Coleman Methodology score 43.5/100) and a high risk of bias. Decision-making in cartilage injuries seems to privilege early return-to-sport, making debridement and microfractures the most used techniques. The lesion size influences the treatment choice. However, the current evidence is limited. Further studies are needed to confirm these findings and establish a case-based approach to treat cartilage injuries in football players based on the specific patient and lesion characteristics and the treatments' potential in terms of both return-to-sport and long-term results. Systematic review, level IV.

Osteochondral Allograft Transplantation for the Treatment of an Acetabular Defect: A Case Report.

A 20-year-old woman presented with a unipolar, 1.8 × 1.8-cm osteochondral defect of the left acetabulum. Osteochondral allograft transplantation was performed using a medial tibial plateau allograft resulting in excellent clinical outcomes across 4 different outcome scores and maintenance of the joint space at 4.3 years postoperatively. Although previous literature has demonstrated long-term clinical success of osteochondral allograft transplantation in knee, excellent clinical outcomes can also be obtained in the hip. Thus, osteochondral allograft transplantation may be a viable treatment option for adolescents and young adults with concomitant cartilage and subchondral bone hip defects.

Outcomes Following Extracellular Matrix Cartilage Allograft for the Management of Osteochondral Lesions of the Talus: A Systematic Review

Introduction/Purpose: The purpose of this systematic review was to evaluate the clinical and radiographic outcomes in patients who received extracellular matrix cartilage allograft (EMCA) during surgical intervention for osteochondral lesions of the talus (OLT). Methods: During January 2023, the PubMed, Embase and Cochrane library databases were systematically reviewed to identify clinical studies evaluating outcomes in patients who received EMCA during surgical intervention for osteochondral lesions of the talus. Data regarding lesion characteristics, surgical characteristics, subjective clinical outcomes, radiographic outcomes, complication rates, failure rates and secondary surgical procedure rates were extracted and analysed. In total, 5 clinical studies were included in this review. Results: In total, 162 patients received EMCA during surgical intervention for OLT at a weighted mean follow-up of 23.8 ± 4.2 months. The weighted mean lesion area was 77.9 ± 42.6 mm2. Overall, 111 (68.5%) of OLTs were located medially, 45 (27.8%) of OLTs were located laterally and 6 (3.7%) OLTs were located centrally. Four studies performed arthroscopic debridement and bone marrow stimulation with ECMA, 3 studies utilized concentrated bone marrow aspirate and 1 study performed autologous osteochondral transplantation. Improvements were noted in AOFAS, FAOS and VAS scores following surgical intervention. The weighted mean post-operative MOCART score was 76.3 ± 2.9. In total, 17 (10.5%) complications were reported across the 5 studies. Twelve failures (7.4%) were recorded, all of which required further surgical intervention. Conclusion: This systematic review demonstrated improvements in subjective clinical outcomes and radiological outcomes at short-term follow-up following surgical intervention for OLTs augmented with ECMA. A low failure rate and moderate complication rate was noted. However, there was marked heterogeneity between the included studies with regards to surgical technique utilized, lesion size and patient cohort size. Further research is warranted to determine the optimal role of ECMA in the management of OLT.

Immune Hypersensitivity Is Associated With Higher Graft Failure Rate After Osteochondral Allograft Transplantation of the Knee

To analyze the effects of 1 or more patient-reported allergies on clinical outcomes, in particular graft failure rate, and patient-reported outcomes (PROs) following osteochondral allograft transplantation (OCA) of the knee. Retrospective review of patients who underwent knee OCA from August 2010 to May 2021 with a minimum of 2-year follow-up. Patients were initially divided into 2 cohorts: those with at least 1 allergy and those without any allergies. Clinical outcomes assessed included graft failure, reoperation rates, deep vein thrombosis/pulmonary embolism, and manipulation under anesthesia/lysis of adhesions (MUA/LOA). PROs assessed, including the visual analog scale (VAS) for pain and satisfaction, the Knee injury and Osteoarthritis Outcome Score (KOOS), and return to sport rates, were compared. In total, 285 patients were included with a mean clinical follow-up of 4.8 ± 2.0 years. The allergy cohort had a significantly higher rate of graft failure (P= .008). In a regression analysis controlling for confounding variables, graft failure remained significantly associated with the presence of medication allergies (odds ratio [OR], 3.631; 95% CI, 1.139-11.577; P= .029). Furthermore, an increasing number of allergies were associated with an increased rate of graft failure (OR, 1.644; 95% CI, 1.074-2.515; P= .022). There was no difference in rate of reoperation, complications, infection, and MUA/LOA. Of the 100 patients who completed PROs, there was no difference in VAS satisfaction, pain, and any of the KOOS outcome scores or return to sport. The presence of 1 or more patient-reported allergies was shown to be significantly associated with OCA graft failure. Furthermore, an increasing number of patient-reported allergies were associated with a higher rate of graft failure. However, there were no significant differences in VAS satisfaction or pain, KOOS symptom, quality of life, pain, or return to sport in patients with at least 1 patient-reported allergy and those without allergies. Level III, retrospective cohort study.

Participation in Sports or Recreational Activities After Osteochondral Allograft Transplantation of the Talus

Background: Fresh osteochondral allograft (OCA) transplantation is a viable treatment option for osteochondral defects of the talus. However, sufficient data are not available on patients’ participation in sports or recreational activities after the procedure. Purpose: To assess whether patients undergoing OCA transplantation of the talus participated in sports or recreational activities postoperatively. Study Design: Case series; level of evidence, 4. Methods: A total of 36 ankles in 34 patients underwent OCA transplantation of the talus. At a mean follow-up of 9.2 years, information on participation in sports or recreational activities pre- and postoperatively was obtained, as well as postoperative pain, function, and satisfaction. Results: The mean age at the time of surgery was 36.1 years (range, 20.5-57.7 years), and 50% of patients were men. The mean graft size was 3.6 cm2 (range, 1-7.2 cm2) or 41.1% of the talar dome. Before the injury, 63.9% of patients (23/36 ankles) reported being highly competitive athletes or well trained and frequently sporting; 36.1% of patients (13/36 ankles) reported sometimes sporting or were nonsporting. Also, 66.7% of patients (24/36 ankles) were able to participate in sports or recreational activities after OCA transplantation and 50% (18/36 ankles) were still participating in sports or recreational activities at the latest follow-up. In a subset of well-trained or highly competitive athletes, 73.9% (17/23 ankles) were able to return to sports or recreational activities at any point after OCA transplantation, and 65.2% (15/23 ankles) were still participating at the latest follow-up. Further surgery occurred in 16.7% of patients (6/36 ankles). Graft survivorship was 94.3% at 5 years and 85.3% at 10 years. There was a significant improvement in the mean Olerud-Molander Ankle Scores, and the mean Foot and Ankle Ability Measure scores were high postoperatively. Moreover, 79.4% of patients (27/34 ankles) were either satisfied or extremely satisfied with the allograft surgery. Conclusion: Fresh OCA transplantation is a reasonable surgical option for osteochondral defects of the talus for young, active patients who have failed previous operative management or have massive defects.

Influence of Concomitant Meniscal Allograft Transplantation on Midterm Outcomes After Osteochondral Allograft Transplantation: A Comparative Matched-Pair Analysis.

Osteochondral allograft transplantation (OCAT) is an accepted knee joint-preserving treatment strategy for focal osteochondral lesions that is often conducted in combination with meniscal allograft transplantation (MAT). Despite its frequent and simultaneous utilization, there remains a lack in the literature reporting on outcomes and failure rates after concomitant procedures. To determine (1) the midterm clinical success rate after OCAT+MAT in comparison with a matched-pair cohort undergoing isolated OCAT, (2) whether patient-specific and procedural variables influence the risk of failure, and (3) patient-reported outcome measures over time. Cohort study; Level of evidence, 3. A single-center matched-pair cohort study was conducted investigating outcomes in patients who underwent OCAT of the medial or lateral femoral condyle with and without MAT between 2004 and 2020. Patients were matched 1:1 by age (±5 years), sex (male or female), body mass index (±5), and grouped Kellgren and Lawrence grade (grades 0-1 or 2-4). The minimum follow-up time was 2 years. Radiographic variables (International Cartilage Regeneration & Joint Preservation Society [ICRS] grade and Kellgren and Lawrence grade) were assessed preoperatively and at follow-up. Subjective patient-reported outcome measures (Lysholm score, Knee injury and Osteoarthritis Outcome Score [KOOS] including subscores, International Knee Documentation Committee [IKDC] score, and visual analog scale score) were collected preoperatively and at follow-up. Clinical failure was defined as revision surgery for graft failure or conversion to total knee arthroplasty. Patient-reported, clinical, and radiographic outcomes were compared between groups. In total, 66 patients (33 treated with isolated OCAT, 33 treated with OCAT+MAT; 57.6% male) with a mean age of 26.3 years (range, 18-62 years) were followed for a mean of 5.6 years (minimum, 2 years; range, 24-218 months). The 2 cohorts showed no difference in Kellgren and Lawrence grade postoperatively (P = .59). There was a significantly higher ICRS grade detected at follow-up in the OCAT+MAT group (2.81 ± 1.10) compared with the OCAT group (2.04 ± 0.96) (P < .05). There were no statistically significant differences between the groups regarding reoperation rate (OCAT: n = 6; OCAT+MAT: n = 13; P = .116), time to reoperation (OCAT: 46.67 ± 47.27 months vs OCAT+MAT: 28.08 ± 30.16 months; P = .061), and failure rate (OCAT: n = 4 [12.1%] vs OCAT+MAT: n = 5 [15.2%]; P = .66). In the OCAT+MAT group, an increase of tibial slope by 1° conferred a 1.65-fold increase in the hazard for failure over decreased slope (hazard ratio, 1.65; 95% CI, 1.10-2.50; P < .05). The overall survival rate was 86% at a mean follow-up of 5.6 years. Patient-reported outcome scores were significantly improved at the final follow-up compared with preoperative status. No significant differences were seen between groups with respect to subjective IKDC, Lysholm, Tegner, and KOOS results, except for the KOOS Symptoms subscale score, which was significantly higher in the OCAT+MAT group than in the OCAT group (mean difference, 14.6; P < .05) and did exceed the minimal clinically important difference threshold of 10.7. Midterm results after isolated OCAT and OCAT+MAT show high rates of healing and sustainable subjective improvement of knee function and quality of life. However, it should be noted that the difference in reoperation rate and time to reoperation between the groups is arguably clinically important and that lack of statistical significance may be because of low power. These results imply that isolated OCAT is an efficient joint-preserving treatment that can be combined with MAT in well-selected patients with meniscal insufficiency without negative influence on global clinical outcomes.

Ex vivo storage of human osteochondral allografts: Long-term analysis over 300 days using a Ringer-based solution.

Large osteochondral defects are a major challenge in orthopedics, for which osteochondral allograft (OCA) transplantation is nowadays considered as an option, especially in young patients. However, a major issue with OCA is the need for graft storage, which ensures adequate cartilage integrity over time. The aim of this study was to test how long a Ringer-based storage solution can provide good graft quality after explantation and thus meet the requirements for OCA. For this purpose, human osteochondral allografts of the knee and ankle were analyzed. Live/Dead analysis was performed and glycosaminoglycan, as well as hydroxyproline content, were measured as crucial chondrocyte integrity factors. Furthermore, biomechanical tests focusing on stress relaxation and elastic compression modulus were performed. The critical value of 70% living chondrocytes, which corresponds to a number of 300 cells/mm², was reached after an average of 16 weeks of storage. In addition, a constant cell shrinkage was observed over time. The amount of glycosaminoglycan and hydroxyroline showed a slight and constant decrease over time, but no significant differences when compared from Day 0 to the values at Weeks 40-43. Biomechanical testing also revealed no significant differences at the different time points. Therefore, the results show that the Ringer-based storage solution at 4°C is able to provide a chondrocyte survival of 70% until Week 16. This is comparable to previously published storage solutions. Therefore, the study contributes to the establishment of a Ringer-based osteochondral allograft transplantation system for countries where medium-based storage solution cannot be approved.

Operative management of osteochondral lesions of the talus: 2024 recommendations of the working group 'clinical tissue regeneration' of the German Society of Orthopedics and Traumatology (DGOU).

The working group 'Clinical Tissue Regeneration' of the German Society of Orthopedics and Traumatology (DGOU) issues this paper with updating its guidelines. Literature was analyzed regarding different topics relevant to osteochondral lesions of the talus (OLT) treatment. This process concluded with a statement for each topic reflecting the best scientific evidence available with a grade of recommendation. All group members rated the statements to identify possible gaps between literature and current clinical practice. Fixation of a vital bony fragment should be considered in large fragments. In children with open physis, retrograde drilling seems to work better than in adults, but even there, the revision rate reaches 50%. The literature supports debridement with bone marrow stimulation (BMS) in lesions smaller than 1.0 cm² without bony defect. The additional use of a scaffold can be recommended in lesions larger than 1.0 cm². For other scaffolds besides AMIC®/Chondro-Gide®, there is only limited evidence. Systematic reviews report good to excellent clinical results in 87% of the patients after osteochondral transplantation (OCT), but donor site morbidity is of concern, reaching 16.9%. There is no evidence of any additional benefit from autologous chondrocyte implantation (ACI). Minced cartilage lacks any supporting data. Metallic resurfacing of OLT can only be recommended as a second-line treatment. A medial malleolar osteotomy has a minor effect on the clinical outcome compared to the many other factors influencing the clinical result.