Fresh Osteochondral Allograft Transplantation Research Articles

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.

Osteochondral Allograft Transplantation in the Knee

Osteochondral injuries of the knee can be a frequent source of debilitating pain and dysfunction. Significant chondral (>1.5-2 cm2) lesions of the femoral condyles can be especially difficult to manage with nonsurgical measures. Fresh osteochondral allograft (OCA) transplantation has been shown to be a reliable surgical procedure to manage a wide array of high-grade focal chondral lesions, with or without subchondral bone involvement. OCA transplantation affords the transfer of a size-matched allograft of mature hyaline cartilage with its associated subchondral bony scaffold. Indications include primary or secondary management of large, high-grade chondral or osteochondral defects secondary to trauma, developmental malformation, osteonecrosis, or other focal degenerative disease. Contraindications include end-stage osteoarthritis, uncorrected malalignment, ligament or meniscus deficiency, and inflammatory joint disease. Improvements in surgical technique, allograft storage, and tissue availability have created more reproducible clinical results and increased chondrocyte viability. Long-term (>10 year) graft survival rates have been shown to be between 70% and 91%, and the procedure has been shown to be cost-effective based on cost per quality-adjusted life year. Finally, OCA transplantation has been shown to provide excellent return to play rate for athletes with medium-to-large cartilage lesions. OCA transplantation is therefore an important option in the treatment algorithm of articular cartilage injuries.

Treatment of osteochondral injuries of the humeral head using fresh osteochondral allograft transplantation

BackgroundLarge osteochondral lesions of the humeral head can result from locked posterior dislocations, avascular necrosis, and osteochondritis dissecans. Fresh osteochondral allograft (OCA) transplantation is a treatment option for young patients with focal osteochondral defects of the humeral head. The purpose of this case series was to assess graft survivorship, subjective patient-reported outcomes (PROMs), and satisfaction among seven patients who underwent OCA transplantation of the humeral head. MethodsWe identified seven patients who underwent humeral head OCA transplantation between 2008 and 2017. A custom questionnaire for patient reported outcome measures including ASES, QuickDASH, Likert satisfaction, and reoperations was mailed to each patient. Clinical failure was defined as further surgery that involved removal of the allograft. ResultsMedian follow-up duration was 10 years (range, 4.6 to 13.5 years) with a median age of 21.6 years (range, 18.5 to 43.5 years). Most patients (86%) reported improved function and reduced pain. At final follow-up, 71% of patients reported ongoing problems with their shoulder including pain, stiffness, clicking/grinding, limited range of motion, and instability. Return to recreational activities was high at 86% but 43% expressed limitations with activity due to their shoulder. Overall satisfaction was high at 71% with mean ASES and QuickDASH scores at 62.4 and 29.2 respectively. Reoperation after OCA occurred in one patient (14%). ConclusionsAmong this case series of seven patients who underwent OCA transplantation of the humeral head, patient satisfaction was high at 10 year follow-up and most returned to recreational activity although most also had persistent shoulder symptoms.

Combined Trochlear, Patellar, Medial and Lateral Condyle Fresh Osteochondral Allograft Transplantation: A Case Report

Background: This is a case report of a 41-year-old man with torsional knee trauma in 2019 and chondral lesions. Previous microfracture had failed, and the patient presented with a dull pain and knee effusion. Imaging revealed multiple focal lesions including trochlea, patella, medial condyle, and lateral condyle. Fresh osteochondral allograft (OCA) transplantation is a versatile treatment for large defects as it is based on mature, living hyaline cartilage attached to a bone interface. A patient with multiple chondral lesions is rare, and this report presents a case with multiple symptomatic large focal lesions in the knee that underwent a fresh OCA in all 3 knee compartments. Indications: Osteochondral allograft is indicated for patients who present with activity-related pain and recurrent knee effusion. Contraindications are patient clinical conditions that may lead to complications, such as tobacco use, inflammatory arthritis, or septic arthritis. Technique Description: After the chondral defect is exposed, an appropriate allograft Mega-OATS sizer (15-30 mm) is chosen. Cartilage and the subchondral bone are drilled until the desired depth. The donor allograft is drilled in the desired diameter, and excess bone is removed according to the previous measurements of the recipient site. The graft is advanced with firm pressure into the created socket. Postoperative rehabilitation includes a limited range of motion and proprioceptive weightbearing in the first 2 weeks but expected total weightbearing and a full range of motion by the sixth week. Results: Range of motion was full by 6 weeks of surgery. The effusion lasted for 2 months after the surgery. Fresh OCA is a good surgical option for patients with multiple large chondral defects. Discussion/Conclusion: Patient satisfaction is high since the mature cartilage leads to a fast rehabilitation compared with the other surgical procedures for large chondral defects. This technique appears to be effective also for multiple focal lesions as presented in this article. 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.

Paper 69: Do Patients Participate in Sports or Recreational Activity After Osteochondral Allograft Transplantation of the Talus?

Objectives: Fresh osteochondral allograft (OCA) transplantation has been reported as a viable treatment option for chondral lesions of the talus, but there is insufficient data regarding patients’ participation in sports or recreational activity following the procedure. The purpose of this study was to assess the frequency of patients who participated in sports or recreational activity following OCA of the talus. Methods: We identified 36 ankles in 34 patients (70% well trained or highly competitive athletes) who underwent OCA transplantation of the talus. Mean age was 36 years and 50% were male. Postoperatively, participation in sport or recreational activity, foot and ankle ability measure (FAAM) scores, American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores, and patient satisfaction with the results of surgery were assessed. Further surgery on the ankle was captured, and OCA failure was defined as any operation that involved removal of the allograft. Results: At a mean follow up of 8.6 years, 67% of patients reported that they had participated in sports or recreational activity after the OCA transplantation. Among those who participated in sport or recreation, 68% returned to their pre-injury sport, 21% played in competitive sports, and 95% participated in regular exercise. Following the OCA transplantation, 17% of ankles required further surgery and 11% were classified as OCA failures (underwent revision OCA transplantation or fusion). There was significant improvement in FAAM and AOFAS ankle-hindfoot scores, and 79% of patients were either satisfied or extremely satisfied with the results of surgery. Survivorship of the OCA transplantation was 94% at five years and 85% at ten years. Conclusions: Fresh OCA transplantation is a reasonable surgical option for osteochondral defects of the talus for young, active patients who have failed non-operative management. Most patients participate in sports or recreational activity following OCA transplantation of the talus.

Early Postoperative CT Scan Provides Prognostic Data on Clinical Outcomes of Fresh Osteochondral Transplantation of the Knee

Background: There is a lack of information regarding the ability of imaging studies to predict clinical outcomes after fresh osteochondral allograft (FOCA) transplantation of the knee. Purpose: To determine the value of computed tomography (CT) scans to predict the clinical outcome of FOCA transplantation using the assessment computed tomography osteochondral allograft (ACTOCA) score. Study Design: Cohort study; Level of evidence, 3. Methods: We prospectively collected data from all consecutive patients who underwent FOCA transplantation for osteochondral knee lesions at one institution between August 2017 and August 2019. All patients were followed up for a minimum of 2 years. CT scans performed 6 months after surgery were evaluated by a musculoskeletal radiologist using the ACTOCA scoring system. The radiologist was blinded to the patient’s medical history. Clinical outcomes were assessed preoperatively and at 12 and 30 months postoperatively using the International Knee Documentation Committee (IKDC) score, the Kujala score, the Tegner activity scale, and the Western Ontario Meniscal Evaluation Tool (WOMET) score. Results: A total of 38 cases were included. The ACTOCA score at 6 months after surgery showed a statistically significant correlation with clinical results at 12 and 30 months. The correlation was better at 30 months, showing a high negative correlation with the IKDC score (−0.663) and a moderate negative correlation with the Kujala, WOMET, and Tegner scores (−0.593; −0.547, and −0.593, respectively) (P < .001). Conclusion: A statistically significant correlation between the mean ACTOCA score on CT scans at 6 months and the clinical results measured by the IKDC, Kujala, WOMET, and Tegner scores at 30 months confirmed the predictive value of the ACTOCA score for use in clinical practice.

Paper 42: Effects of Blood Type Mismatching on Functional Graft Survival after Osteochondral Allograft Transplantation

Objectives:To explore a factor that may contribute to potentially detrimental sub-rejection immune responses, we compared donor and recipient blood types following osteochondral allograft (OCA) transplants from a subset of patients in an IRB-approved dedicated lifelong registry to determine potential relationships for blood type mismatches with documented graft failures. The study was designed to test the hypothesis that OCA transplantation patients receiving blood type mismatched allografts would be more likely to require OCA revision or artificial arthroplasty surgery compared to those receiving donor-recipient matched allografts.Methods:A subset of patients was selected from those enrolled (n=414) in our center’s IRB-approved lifelong registry for OCA transplantation clinical outcomes. This subset included patients with complete donor and recipient ABO and Rh Factor data available such that there was a 2:1 ratio of successful versus failed outcomes for age-, BMI-, and joint-matched OCA transplant recipients for statistical analyses. Donor blood type information was obtained from the respective tissue banks. Recipient blood type information was obtained from electronic medical records. Patients who required OCA revision or artificial arthroplasty were defined as graft failures. Outcomes were assessed for all patients included in the blood type mismatching analyses. Osteochondral tissues that were resected from the knee, hip, and ankle of patients undergoing standard-of-care revision or arthroplasty surgeries, and that otherwise would be discarded, were recovered for histologic assessments. Subjective histologic assessments were performed by a pathologist who was blinded to patient demographics, blood typing information, outcomes data, and tissue source. When aggregates of lymphocytes and plasma cells were observed surrounding small blood vessels (consistent with an immune response), immunohistochemistry for CD3, CD8, and CD20 was performed to further characterize the lymphocytes (T cell marker, cytotoxic T lymphocytes, and B cell marker, respectively) for subjective assessment of relevant immune responses. Subjects were grouped by ABO blood type, Rh Factor, and both. Histologically evaluated failures were separated by immune response as positive or negative. Fisher’s exact tests were used for statistical analyses with a p-value of less than 0.05 set a priori to define statistical significance.Results:A total of 103 patients were included for analysis with 33 of these requiring OCA revision or artificial arthroplasty. Of the clinical failures, 18 had previously transplanted osteochondral allograft tissues recovered for histological assessment. Twelve (66%) of these recovered OCAs had aggregates of CD3+, CD8+, and CD20+ lymphocytes around small blood vessels in the bone marrow spaces and adipose/collagenous tissue of the previously transplanted allograft. The remaining resected OCAs (34%) did not show a similar pattern of T- and B-cell infiltrates around blood vessels. Other histologic abnormalities associated with failed OCAs included avascular necrosis, subchondral micro and macro fractures, subchondral collapse, and/or articular cartilage erosion or delamination. No statistically significant differences in proportions for success versus failure based on mismatches for ABO type, Rh Factor, or both were noted. Similarly, no statistically significant differences in proportions for positive versus negative immune responses based on mismatches for ABO type, Rh Factor, or both were noted.Conclusions:Donor-recipient mismatches for ABO blood type and/or Rh Factor were not associated with higher likelihood for patients to require OCA revision or artificial arthroplasty surgery. Similarly, donor-recipient mismatches for ABO blood type and/or Rh Factor were not associated with higher likelihood for positive immune responses in previously implanted OCA tissues recovered from patients who required revision or artificial arthroplasty surgeries. However, two-thirds of the tissues recovered from graft failure cases had T- and B-cell infiltrates, suggesting sub-rejection immune responses occur after OCA transplantation that should be further investigated to determine potential mechanistic relationships with graft failures. The results of the present study support current clinical practice for transplantation of fresh OCAs, which does not require HLA or blood type matching or immunosuppressive medication for recipients. However, histologic assessments suggest that sub-rejection immune responses may play a role in graft failures and should be further investigated.

Midterm Prospective Evaluation of Structural Allograft Transplantation for Osteochondral Lesions of the Talar Shoulder.

In cases of large osteochondral lesions of the talus (OLTs), fresh structural or bulk osteochondral allograft transplantation has yielded favorable outcomes in several retrospective and few prospective case series. The purpose of this study was to prospectively evaluate patients who received fresh structural allograft transplantation of the talar shoulder. A prospective evaluation of patients who received a fresh structural allograft of an OLT was performed. Preoperative imaging included magnetic resonance imaging (MRI) and/or computed tomography (CT) with plain radiographs. The following patient-reported outcomes questionnaires were administered preoperatively and yearly after surgery: 36-Item Short-Form Health Survey (SF-36), visual analog scale (VAS) for pain, and the Short Musculoskeletal Functional Assessment (SMFA). Preoperative and postoperative imaging were evaluated for allograft assimilation, evidence of arthritic changes, or functional range of motion abnormalities. Thirty-one patients with a mean age of 41.4 years (±14.1, range 18-69) underwent structural fresh osteochondral allograft transplantation to the talar shoulder and were included in this study. The mean follow-up was 56.2 months (±36.1, range 24-142). The majority of patients were female (n=17, 54.8%), reported some history of prior ankle trauma (n=21, 67.7%), and underwent prior ankle surgery (n=23, 74.2%). The mean lesion size on CT scan was 1879 mm3 (n = 27) compared to the mean lesion size of 3877 mm3 (n = 21) on MRI. There was a significant improvement in the mean preoperative VAS score (P < .0001), SF-36 score (P < .0005), SMFA bother index (P < .0015), and the SMFA function index (P < .0001) at final follow-up. A total of 15 (48.4%) patients underwent an additional surgery following their osteochondral allograft transplant, most commonly arthroscopic debridement or removal of hardware, performed at an average of 25.2 (±13.0) from their index procedure. There was one failure that required a total ankle replacement. The overall graft survival rate was 96.8%. Fresh, structural allograft transplantation resulted in significant improvement in patient-reported postoperative pain and function in patients suffering from OLTs. The graft survival rate was 96.8% at a mean of 56.2 months follow-up, with half of patients requiring a second procedure. Level IV, prospective case series.

Osteochondral Allograft Transplantation for a Cartilage Defect of the Humeral Capitellum

Background: Cartilage defects of the humeral capitellum most frequently present as osteochondritis dissecans (OCD) in young overhead athletes, such as baseball players. Historically, surgical options have included debridement, marrow stimulation, and osteochondral autograft transplantation. Fresh osteochondral allograft (OCA) transplantation comprises an additional treatment option that can structurally restore osteochondral defects and has demonstrated satisfactory outcomes without the donor-site morbidity associated with osteochondral autograft transplantation. Indication: OCA transplantation provides structural restoration of the articular surface and can be used for large (&gt;1 cm diameter) lesions not amenable to refixation. Additionally, OCA transplantation can address both chondral and subchondral pathology and is suited for the treatment of failed previous surgical interventions, such as debridement or marrow stimulation. Technique Description: Following diagnostic arthroscopy, an anconeus splitting mini-open approach was performed to expose the capitellar defect. The defect was measured to be 10 mm, and a central guide pin was placed. A 10-mm reamer was used to prepare the defect bed to a depth of 8 mm. An OCA plug was then cut from a fresh femoral hemicondyle to match the prepared defect. The graft was soaked in bone marrow aspirate concentrate harvested from the iliac crest, and the plug was then inserted into the defect and tamped to be concentric with the surrounding articular cartilage. Results: OCA transplantation of the capitellum allows for the restoration of the articular surface with a structural graft and can be used for large defects and revision cases. While OCA transplantation is well described in the knee with long-term efficacy, the application of this technique to the capitellum is relatively recent. Recent case series for the capitellum have displayed significant improvements in patient-reported outcome measures and predictable return to sports. Discussion/Conclusion: OCA transplantation for the humeral capitellum provides an effective treatment option for large, unstable cartilage lesions not amenable to refixation. The procedure allows for restoration of the articular surface and can provide improvements in pain and function as well as return to sport.

Computerized tomography scan evaluation after fresh osteochondral allograft transplantation of the knee correlates with clinical outcomes

PurposeTo determine the correlation between the assessment computed tomography osteochondral allograft (ACTOCA) scoring system and clinical outcomes scores. The hypothesis was that the ACTOCA score would show sufficient correlation to support its use in clinical practice.MethodsWe prospectively collected data from all consecutive patients who underwent cartilage restitution with fresh osteochondral allograft (FOCA) transplantation for osteochondral lesions of the knee and had a minimum follow-up of two years. CT scans were performed at three, six and 24 months post-operatively. A musculoskeletal radiologist blinded to the patients’ medical history evaluated the scans using the ACTOCA scoring system. Clinical outcomes collected preoperatively and at three, six and 24 months postoperatively were evaluated using the International Knee Documentation Committee (IKDC), Kujala, the Western Ontario Meniscal Evaluation Tool (WOMET), and the Tegner Activity Scale.ResultsThe mean total ACTOCA score showed a statistically significant correlation with the clinical outcome. The correlation was optimal at 24 months. We found a high negative correlation with the IKDC, Kujala and Tegner (− 0.737; − 0.757, and − 0.781 respectively), and a moderate negative correlation with WOMET (− 0.566) (p < 0.001). IKDC, Kujala, WOMET, and Tegner scores showed a significant continuous improvement in all scores (p < 0.001).ConclusionThe mean total ACTOCA score showed a linear correlation with clinical results in IKDC, Kujala, WOMET, and Tegner scores, being the highest at 24 months post-surgery. This finding supports the use of ACTOCA to standardize CT scan reports following fresh osteochondral allograft transplantation in the knee.

Posterior Approach for the Treatment of an Osteochondral Defect on the Posterior Lateral Femoral Condyle

Osteochondral defects of the knee often occur as a result of traumatic injury, repetitive microtrauma, or genetic predisposition. Smaller lesions can be treated nonoperatively in younger patient populations; however, large symptomatic lesions require surgical intervention using a fresh osteochondral allograft transplant. Although osteochondral defects classically appear on the lateral aspect of the medial femoral condyle, there have been cases in which the lesion is located on the posterior aspect of the lateral femoral condyle. To access these posteriorly located lesions, the surgeon must utilize a complex posterior approach in order to successfully manage these lesions. While care must be taken to protect the neurovascular bundle in this area, this technique allows for excellent exposure and optimal graft placement.

Mid-Term Prospective Evaluation of Structural Allograft Transplantation for Osteochondral Lesions of the Talar Shoulder

Category:AnkleIntroduction/Purpose:The management of large osteochondral lesions of the talar shoulder remains a clinical challenge. Their size, three-dimensional geometry, and subchondral cystic degeneration often preclude treatment with traditional measures such as microfracture and osteochondral autograft transplantation. Structural or bulk osteochondral allograft transplantation has demonstrated efficacy in several retrospective reviews. The purpose of this study was to prospectively evaluate patients who received fresh structural allograft transplantation to the talus.Methods:A prospective evaluation of consecutive patients who underwent fresh structural allograft transplantation for an OLT form 2010 to 2019 was performed under Institutional Review Board approval. All patients failed a minimum of 6 months of conservative management. Preoperative MRI and/or CT, as well as plain radiographs were obtained on all patients. The following patient reported outcomes questionnaires were administered preoperatively and yearly after surgery: 100mm VAS pain scale, AOFAS Ankle-Hindfoot Scale, SF-36, and the Short Musculoskeletal Functional Assessment (SMFA). Pre- and postoperative radiographs were assessed for allograft incorporation and the development of arthritis.Results:27 patients underwent fresh osteochondral allograft transplantation and were followed for a minimum of 2 years. The mean follow-up was 5 years (range 2-11). The average size of the OLT was 2,269 mm3 (range 813-8,366) based on CT imaging and 5,797 mm3 (range 1,136-12,489) based on MRI imaging. There was significant improvement in the VAS pain score, AOFAS Ankle- Hindfoot Scale score, the SF-36 total score, and the SMFA functional and bother indices (Figure 1). Thirteen (48%) of the patients required subsequent surgery. Twelve underwent removal of hardware and joint debridement and one patient underwent isolated joint debridement. At the time of these surgeries, two grafts demonstrated cartilage delamination. One of these patients had continued pain and progression of arthritis without additional surgery and one was converted to an ankle replacement. Therefore, the failure rate was 7%.Conclusion:Significant improvement in pain and function can be achieved with structural allograft transplantation for large OLTs. However, it is important to council patients that painful hardware and stiffness can occur in approximately one-half of patients. An unstable graft and cartilage delamination are indicators of subsequent failure. The use of a structural allograft does not preclude subsequent ankle arthrodesis or arthroplasty.

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.

Histological and Inflammatory Cytokine Analysis of Osteochondral Lesions of the Talus After Failed Microfracture: Comparison With Fresh Allograft Controls.

Background:The most common first-line treatment of osteochondral lesions of the talus (OLTs) is microfracture. Although many patients do well with this procedure, a number fail and require reoperation. The mechanism of failure of microfracture is unknown, and to our knowledge there has been no research characterizing failed microfracture regarding histological and inflammatory makeup of these lesions that may contribute to failure.Purpose:To characterize the structural and biochemical makeup of failed microfracture lesions.Study Design:Case series; Level of evidence, 4.Methods:Specimens from 8 consecutive patients with symptomatic OLTs after microfracture who later underwent fresh osteochondral allograft transplantation were analyzed. For each patient, the failed microfracture specimen and a portion of the fresh allograft replacement tissue were collected. The allograft served as a control. Histology of the failed microfracture and the allograft replacement was scored using the Osteoarthritis Research Society International (OARSI) system. Surface roughness was also compared. In addition, tissue culture supernatants were analyzed for 16 secreted cytokines and matrix metalloproteinases (MMPs) responsible for inflammation, pain, cartilage damage, and chondrocyte death.Results:The OARSI grade, stage, and total score as well as surface smoothness were significantly worse in the failed microfracture sample, indicating better cartilage and bone morphology for the allografts compared with the failed microfracture lesions. Analyzed cytokines and MMPs were significantly elevated in the microfracture tissue culture supernatants when compared with fresh osteochondral tissue supernatants.Conclusion:These data demonstrate a significantly rougher cartilage surface, cartilage and subchondral bone histology that more closely resembles osteoarthritis, and elevated inflammatory cytokines and MMPs responsible for pain, inflammation, cartilage damage, and chondrocyte death when compared with fresh osteochondral allografts used as controls.

Pre-operative Mental Health Predicts Clinically Meaningful Outcomes after Osteochondral Allograft for Cartilage Defects of the Knee: A Machine Learning Analysis

Objectives:Fresh osteochondral allograft transplantation (OCA) is an effective method of treating symptomatic cartilage defects of the knee. This cartilage restoration technique involves the single-stage implantation of viable, mature hyaline cartilage into chondral or osteochondral lesion. Predictive models for reaching the clinically meaningful outcome among patients undergoing OCA for cartilage lesions of the knee remain under investigation. The purpose of the study was to apply machine learning to determine which preoperative variables are predictive for achieving the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) at one and two years after OCA for cartilage lesions of the knee.Methods:Data were analyzed for patients who underwent OCA of the knee by a two high-volume fellowship-trained cartilage surgeons before May 1, 2018. The International Knee Documentation Committee (IKDC) subjective form, Knee Outcome Survey-Activities of Daily Living (KOS-ADL), and Mental Component (MCS) and Physical Component (PCS) Summaries of the SF-36 were administered preoperatively and at one and two-years postoperatively. A total of 84 predictive models were created using 7 unique architectures to detect achievement of the MCID for each of the four outcome measures and the SCB for the IKDC and KOS-ADL at both timepoints. Data inputted into the models included prior and concomitant surgical history, laterality, sex, age, body mass index (BMI), intraoperative findings, and patient-reported outcome measures (PROMs). Shapley additive explanations (SHAP) analysis identified predictors of reaching the MCID and SCB.Results:Of the 185 patients who underwent OCA for the knee and met eligibility criteria from an institutional cartilage registry, 135 (73%) patients were available for one-year follow-up and 153 (83%) patients with two-year follow-up. In predicting outcomes after OCA in terms of the IKDC, KOS-ADL, MCS, and PCS at one and two years, AUCs of the top performing models ranged from fair (0.72) to excellent (0.94). Lower baseline mental health (MCS), higher baseline physical health (PCS) and knee function scores (KOS-ADL, IKDC subjective), lower baseline activity demand (Marx, Cincinnati Sports), worse pain symptoms (Cincinnati pain, SF36 pain), and higher BMI were thematic predictors contributing to failure to achieve the MCID or SCB at one and two-years postoperatively.Conclusions:Our machine learning models were effective in predicting outcomes and elucidating the relationships between baseline factors contributing to achieving the MICID for osteochondral allograft transplantation of the knee. Patients who preoperatively report poor mental health, catastrophize pain symptoms, compensate with higher physical health and knee function, and exhibit lower activity demands are at risk for failing to reach clinically meaningful outcomes after OCA of the knee.

Optimizing Graft Extraction From the Femoral Condyle for Fresh Osteochondral Allograft Transplantation in Treating Osteochondritis Dissecans of the Capitellum: Best Fit Based on Radius of Curvature.

Osteochondritis dissecans (OCD) of the capitellum is a common cause of pain and dysfunction in adolescents that engage in repetitive elbow loading. For large, unstable lesions fresh osteochondral allograft transplantation (FOCAT) from the femoral condyle has been described as an effective treatment. Current practice involves significant guesswork in obtaining an appropriately sized graft, with anatomic variations resulting in poor graft fit. No studies currently exist that analyze and identify the best distal femur FOCAT graft site to repair OCD lesions of the capitellum based on the radius of curvature (ROC) and simulated matching. Computed tomography scans of the elbow were used to estimate the subchondral bone ROC of capitella in adolescents aged 11 to 21 years. The capitellar location used corresponds to the most commonly reported site of OCD lesions in the elbow. Computed tomography scans of the lower extremity were used to estimate the subchondral bone ROC of 4 potential donor femoral condyle grafts. ROC from distinct regions at the posterior section of both the medial and lateral femoral condyles were measured: 2 areas representing 10 mm grafts from the center (MC1 and LC1), and 2 areas estimating 10 mm grafts posterior and adjacent to the physeal scar (MC2 and LC2). Intraobserver and interobserver reliability measurements were preformed to corroborate precision and validate the method. The mean ROC of healthy subchondral bone at the region of the capitellum were OCD lesions most commonly occur was 9.79±1.39 mm. The mean ROC of MC1 was 18.61±2.26 mm. The average ROC of the MC2 was 15.23±1.43 mm. The average ROC of LC1 was 16.47±1.34 mm. The average ROC of LC2 was 18.19±3.09 mm. After 15,000 simulated condyle-to-capitellar site matchings based on these measurements, a good fit graft was achieved at a frequency of 15%. No site measured from the femoral condyle demonstrated a subchondral ROC that exactly matched the subchondral ROC of the capitellum at the center location where OCD lesions most commonly occur; of the locations measured, a 10 mm section from MC2 demonstrated the closest match. On the basis of this analysis, extracting a graft from MC2 has the potential to further optimize FOCAT fit to the capitellum. Level III.

Effect of Preoperative Imaging and Patient Factors on Clinically Meaningful Outcomes and Quality of Life After Osteochondral Allograft Transplantation: A Machine Learning Analysis of Cartilage Defects of the Knee

Background: Fresh osteochondral allograft transplantation (OCA) is an effective method of treating symptomatic cartilage defects of the knee. This restoration technique involves the single-stage implantation of viable, mature hyaline cartilage into a chondral or osteochondral lesion. The extent to which preoperative imaging and patient factors predict achieving clinically meaningful outcomes among patients undergoing OCA for cartilage lesions of the knee remains unknown. Purpose: To determine the predictive relationship of preoperative imaging, preoperative patient-reported outcome measures (PROMs), and patient demographics with achievement of the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) for functional and quality-of-life PROMs at 2 years after OCA for symptomatic cartilage defects of the knee. Study Design: Case-control study; Level of evidence, 3 Methods: Data were analyzed for patients who underwent OCA before May 1, 2018, by 2 high-volume fellowship-trained cartilage surgeons. The International Knee Documentation Committee (IKDC) subjective form, Knee Outcome Survey–Activities of Daily Living (KOS-ADL), and mental and physical component summaries of the SF-36 were administered preoperatively and at 2 years postoperatively. A total of 42 predictive models were created using 7 unique architectures to detect achievement of the MCID for each of the 4 outcome measures and the SCB for the IKDC and KOS-ADL. Data inputted into the models included sex, age, body mass index, baseline PROMs, lesion size, concomitant ligamentous or meniscal tear, and presence of “bone bruise” or osseous edema. Shapley additive explanations plot analysis identified predictors of reaching the MCID and SCB. Results: Of the 185 patients who underwent OCA for the knee and met eligibility criteria from an institutional cartilage registry, 153 (83%) had 2-year follow-up. Preoperative magnetic resonance imaging (MRI), baseline PROMs, and patient demographics best predicted reaching the 2-year MCID and SCB of the IKDC and KOS-ADL PROMs, with areas under the receiver operating characteristic curve of the top-performing models ranging from good (0.88) to excellent (0.91). MRI faired poorly (areas under the curve, 0.60-0.68) in predicting the MCID for the mental and physical component summaries. Higher body mass index, knee malalignment, absence of preoperative osseous edema, concomitant anterior cruciate ligament or meniscal injury, larger defect size, and the implantation of >1 OCA graft were consistent findings contributing to failure to achieve the MCID or SCB at 2 years postoperatively. Conclusion: Our machine learning models demonstrated that preoperative MRI, baseline PROMs, and patient demographics reliably predict the ability to reach clinically meaningful thresholds for functional knee outcomes 2 years after OCA for cartilage defects. Although clinical improvement in knee function can be reliably predicted, improvements in quality of life after OCA depend on a comprehensive preoperative assessment of the patient’s perception of his or her mental and physical health. Absence of osseous edema, concomitant anterior cruciate ligament or meniscal injury, larger lesion size on MRI, knee malalignment, and elevated body mass index are predictive of failure to achieve 2-year functional benefits after OCA of the knee.

Association Between Preoperative Mental Health and Clinically Meaningful Outcomes After Osteochondral Allograft for Cartilage Defects of the Knee: A Machine Learning Analysis

Background: Fresh osteochondral allograft transplantation (OCA) is an effective method of treating symptomatic cartilage defects of the knee. This cartilage restoration technique involves the single-stage implantation of viable, mature hyaline cartilage into the chondral or osteochondral lesion. Predictive models for reaching the clinically meaningful outcome among patients undergoing OCA for cartilage lesions of the knee remain under investigation. Purpose: To apply machine learning to determine which preoperative variables are predictive for achieving the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) at 1 and 2 years after OCA for cartilage lesions of the knee. Study Design: Case-control study; Level of evidence, 3. Methods: Data were analyzed for patients who underwent OCA of the knee by 2 high-volume fellowship-trained cartilage surgeons before May 1, 2018. The International Knee Documentation Committee questionnaire (IKDC), Knee Outcome Survey–Activities of Daily Living (KOS-ADL), and Mental Component (MCS) and Physical Component (PCS) Summaries of the 36-Item Short Form Health Survey (SF-36) were administered preoperatively and at 1 and 2 years postoperatively. A total of 84 predictive models were created using 7 unique architectures to detect achievement of the MCID for each of the 4 outcome measures and the SCB for the IKDC and KOS-ADL at both time points. Data inputted into the models included previous and concomitant surgical history, laterality, sex, age, body mass index (BMI), intraoperative findings, and patient-reported outcome measures (PROMs). Shapley Additive Explanations (SHAP) analysis identified predictors of reaching the MCID and SCB. Results: Of the 185 patients who underwent OCA for the knee and met eligibility criteria from an institutional cartilage registry, 135 (73%) patients were available for the 1-year follow-up and 153 (83%) patients for the 2-year follow-up. In predicting outcomes after OCA in terms of the IKDC, KOS-ADL, MCS, and PCS at 1 and 2 years, areas under the receiver operating characteristic curve (AUCs) of the top-performing models ranged from fair (0.72) to excellent (0.94). Lower baseline mental health (MCS), higher baseline physical health (PCS) and knee function scores (KOS-ADL, IKDC Subjective), lower baseline activity demand (Marx, Cincinnati sports), worse pain symptoms (Cincinnati pain, SF-36 pain), and higher BMI were thematic predictors contributing to failure to achieve the MCID or SCB at 1 and 2 years postoperatively. Conclusion: Our machine learning models were effective in predicting outcomes and elucidating the relationships between baseline factors contributing to achieving the MCID for OCA of the knee. Patients who preoperatively report poor mental health, catastrophize pain symptoms, compensate with higher physical health and knee function, and exhibit lower activity demands are at risk for failing to reach clinically meaningful outcomes after OCA of the knee.

Osteochondral Allograft Transplant of the Patella Using Femoral Condylar Allografts: Magnetic Resonance Imaging and Clinical Outcomes at Minimum 2-Year Follow-up

Background:Fresh osteochondral allograft transplant (OCA) has good outcomes in the knee. However, donor tissue for patellar OCA is limited. Outcomes after nonorthotopic OCA of the patella using more readily available femoral condylar allograft (FCA) tissue have not been previously reported.Purpose:To assess short-term magnetic resonance imaging (MRI) and minimum 2-year clinical outcomes of nonorthotopic patellar OCA using an FCA donor.Study Design:Case series; Level of evidence, 4.Methods:A prospective institutional cartilage registry was reviewed to identify patients treated with patellar OCA using an FCA donor between August 2009 and June 2016. OCA plugs were obtained from the FCA at its trochlear-condylar junction and implanted into the recipient patellar lesion. Early postoperative MRI scans were graded by a blinded musculoskeletal radiologist using the Osteochondral Allograft MRI Scoring System (OCAMRISS). International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), Knee Outcomes Survey–Activities of Daily Living (KOS-ADL), and pain visual analog scale (VAS) scores were collected preoperatively and at minimum 2 years postoperatively, and outcomes were compared using the paired t test.Results:A total of 25 patients were included for clinical outcome analysis and 20 patients for MRI analysis. MRI scans obtained at a mean of 11.4 months (range, 6-22 months) postoperatively showed a mean total OCAMRISS score of 9.0 (range, 7-11); mean bone, cartilage, and ancillary subscores were 2.6, 3.7, and 2.6, respectively. At the latest follow-up (mean, 46.5 months; range, 24-85 months), postoperative improvements were noted in IKDC (from 45.0 to 66.2; P = .0002), KOS-ADL (from 64.3 to 80.4; P = .0012), and VAS (from 5.1 to 3.4; P = .001) scores, with IKDC and KOS-ADL scores above the corresponding previously reported minimal clinically important difference.Conclusion:In this study, patellar OCA using nonorthotopic FCA led to significant short-term improvements in pain and patient-reported outcomes. The majority of nonorthotopic patellar grafts demonstrated full osseous incorporation and good restoration of the articular surface on MRI at short-term follow-up.

A Systematic Review of Fresh Osteochondral Allograft Transplantation for Osteochondral Lesions of the Talus

Category:AnkleIntroduction/Purpose:The term osteochondral lesion of the talus (OLT) refers to any pathology of the talar articular cartilage and corresponding subchondral bone. In general, OLTs can pose a formidable treatment challenge to the orthopaedic surgeon due to the poor intrinsic ability of cartilage to heal as well as the tenuous vascular supply to the talus. Although many treatment options exist, including microfracture, retrograde drilling, autologous chondrocyte implantation (ACI), and osteochondral autograft transfer system (OATS) these options may be inadequate to treat large cartilage lesions. Osteochondral allografts have demonstrated promise as the primary treatment for OLTs with substantial cartilage and bone involvement. To our knowledge, this is the first systematic review of outcomes after fresh osteochondral allograft transplantation for OLTs.Methods:PudMed, the Cochrane Central Register of Controlled Trials, EMBASE, and Medline were searched using PRISMA guidelines. Studies that evaluated outcomes in adult patients after fresh osteochondral allograft transplantation for chondral defects of the talus were included. Operative results, according to standardized scoring systems, such as the AOFAS Ankle/Hindfoot scale and the Visual Analog Scale were compared across various studies. The methodological quality of the included studies was assessed using the Coleman methodology score.Results:There were a total of 12 eligible studies reporting on 191 patients with OLTs with an average follow-up of 56.8 months (range 6-240). The mean age was 37.5 (range 17-74) years and the overall graft survival rate was 86.6%. The AOFAS Ankle/Hindfoot score was obtained pre- and postoperatively in 6 of the 12 studies and had significant improvements in each (P<0.05). Similarly, the VAS pain score was evaluated in 5 of the 12 studies and showed significant decreases (P<0.05) from pre- to postoperatively with an aggregate mean preoperative VAS score of 7.3 and an aggregate postoperative value of 2.6. The reported short-term complication rate was 0%. The overall failure rate was 13.4% and 21.6% percent of patients had subsequent procedures.Conclusion:The treatment of osteochondral lesions of the talus remains a challenge to orthopaedic surgeons. From this systematic review, one can conclude that osteochondral allograft transplantation for osteochondral lesions of the talus results in predictably favorable outcomes with an impressive graft survival rate and high satisfaction rates at intermediate follow-up.