Differential analysis of the impact of lesions' location on clinical and radiological outcomes after the implantation of a novel aragonite-based scaffold to treat knee cartilage defects.

PURPOSE: There is limited comparative evidence on patient outcomes following cartilage repair in various knee compartments. The aim of this study was to compare clinical and imaging outcomes after treating cartilage defects in femoral condyles and trochlea with either an aragonite-based scaffold or surgical standard of care (SSoC, i.e., debridement/microfractures) in a large multicentre randomized controlled trial. METHODS: 247 patients with up to three knee joint surface lesions (ICRS grade IIIa or above) in the femoral condyles, trochlea or both ("mixed"), were enrolled and randomized to surgery with either a cell-free aragonite scaffold or SSoC. Patients were followed for up to 48 months by analysing subjective scores (KOOS and IKDC), radiological outcomes (defect filling on MRI), as well as treatment failure rates and adverse events. A differential analysis of outcomes for condylar, trochlear and mixed lesions was performed. RESULTS: The scaffold group significantly outperformed the SSoC group regardless of lesion location with statistically significantly better KOOS Overall scores at 24 months (all p ≤ 0.0009) and 48 months (all p ≤ 0.02). Similar results were observed for KOOS subscales and IKDC scores. For KOOS responder rates, superiority of the implant group was demonstrated at 24, 36, and 48 months (all p ≤ 0.004). Higher defect filling on MRI for implants was observed for all locations. Lower treatment failure rates for the implant were observed in condylar and mixed lesions. CONCLUSION: The aragonite-based scaffold was safe and effective regardless of the defect location, providing superior clinical and radiological outcomes compared to SSoC up to four years follow-up. LEVEL OF EVIDENCE: I - Randomized controlled trial.

An implantable shock absorber yields an 85% survival-from-arthroplasty rate through 5 years in working-age patients with medial compartment knee osteoarthritis.

PURPOSE: To evaluate the 5-year rate of survival without undergoing arthroplasty or high tibial osteotomy (HTO) in subjects with mild-to-moderate medial compartment knee osteoarthritis (OA) who were treated with an implantable shock absorber (ISA) system. METHODS: Three prospective, sequential, multicenter, international, single-arm clinical trials were conducted comprising subjects who received an ISA for symptomatic medial knee OA after failing ≥ 6 months of conservative therapy. Study outcomes were analyzed cumulatively and by enrollment group when all subjects' follow-up data exceeded the 2-year threshold after ISA implantation. Primary outcome was survival rate without conversion to arthroplasty/HTO. Secondary outcomes were changes in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores after ISA implantation. RESULTS: All 171 enrolled subjects (age 51 ± 9 years, body-mass index 28.5 ± 3.5 kg/m2, 38% female; study knee Kellgren-Lawrence score 2.7 ± 0.9 points) were followed for a minimum of 2, and up to 5, years after device implantation. Overall, 90.6% (155/171) of subjects survived without requiring arthroplasty/HTO at last follow-up (mean 3.2 ± 1.6 years). The Kaplan-Meyer median 3- and 5-year survival-without-arthroplasty point estimates were 89.8% (95% CI 86.5‒95.7%) and 84.9% (95% CI 75.1‒91.1%), respectively. The median 3-year estimated survival rate for the most recent study (n = 81) was 97.3%. The mean WOMAC Pain score decreased 71% from baseline to last follow-up after ISA implantation, from 58 ± 13 to 16 ± 17 points (p < 0.0001). The Function score improved 69%, decreasing from 56 ± 18 to 17 ± 17 points (p < 0.0001). CONCLUSIONS: In younger patients with mild-to-moderate symptomatic medial compartment knee OA, implantation of the ISA device resulted in a 5-year survival rate of 85% from undergoing arthroplasty or HTO. The ISA system may be an effective treatment option for working-age patients with medial knee OA who are not candidates for or do not desire more invasive surgical approaches. LEVEL OF EVIDENCE: II.

Treatment of unstable knee osteochondritis dissecans in the young adult: results and limitations of surgical strategies-The advantages of allografts to address an osteochondral challenge.

Joint surface incongruence resulting from osteochondritis dissecans (OCD) alters the articular physiologic congruence, increasing the contact stress on adjacent joint surfaces and accelerating wear and the cascade of joint degeneration. Accordingly, the restoration of articular surface integrity is of major importance, especially in young adults where, in lesions left untreated or following simple fragment excision, early osteoarthritis can be anticipated. Therefore, the treatment algorithm in unstable knee OCD of the young adult foresees surgical options to restore the articular surface. Several procedures have been proposed, including refixation of the detached fragment bone marrow stimulation, osteochondral autograft implantation, fresh osteochondral allograft transplantation, and cell-based or cell-free regenerative techniques. The aim of this review was to summarize the evidence for these surgical strategies, reporting their results and limitations. The overall evidence documents positive results for each of the assorted surgical procedures applied to treat unstable OCD, thus indicating support for their selected use to treat osteochondral defects paying particular attention to their specific indications for the lesion characteristics. The fixation of a good quality fragment should be pursued as a first option, while unfixable small lesions may benefit from autografts. For large lesions, available cell-based or cell-free osteochondral scaffold are a feasible solution but with limitation in terms of regenerated tissue quality. In this light, fresh allografts may offer articular surface restoration with viable physiologic osteochondral tissue providing a predictably successful outcome, and therefore they may currently represent the most suitable option to treat unstable irreparable OCD lesion in young adults. LEVEL OF EVIDENCE: V.

MRI of the knee in adults.

MRI of the knee is a crucial component for evaluating symptomatic patients. An awareness of normal and abnormal appearances assists in clinical decision making. Chronic degenerative changes and focal traumatic injuries can sometimes be confused with one another, so differentiation is crucial. As technology continues to evolve, identifying early disease and preventing disease progression will become an integral part of MRI interpretation.

MRI of the shoulder in adults.

MRI can be used to assist in distinguishing pathology and anatomic disruptions adjacent to shoulder articulations and is a crucial tool in evaluating the symptomatic shoulder. The differentiation of traumatic and degenerative etiologies is important for patient management. A review of common adult degenerative and posttraumatic conditions can help familiarize general orthopaedic surgeons and sports medicine care providers to the perspective of shoulder specialists and musculoskeletal radiologists.

Comparison of Patient-Reported Outcomes for Immediate Unrestricted Weightbearing Versus Restricted Rehabilitation Protocols After Osteochondral Allograft Transplantation to the Distal Femur.

Background: There is no standardized rehabilitation protocol after osteochondral allograft (OCA) transplantation surgery to the distal femur. The spectrum of recommendations includes restrictions to toe-touch weightbearing (TTWB) for 6 weeks and immediate weightbearing as tolerated (WBAT). Purpose/Hypothesis: The purpose of this study was to compare outcomes for immediate unrestricted WBAT to restricted TTWB after OCA transplantation to the distal femur. It was hypothesized that the immediate WBAT protocol would be noninferior to delayed, restricted TTWB. Study Design: Retrospective cohort study. Methods: A total of 74 patients who underwent press-fit, dowel technique OCA transplantation to the femoral condyle(s) for contained (International Cartilage Repair Society grade 3-4) lesions were identified in the Metrics of Osteochondral Allograft multicenter database: 36 patients (18 women/18 men) who were prescribed TTWB were allocated to the control cohort and 38 patients (21 women/17 men) who were prescribed WBAT were allocated to the test cohort. Baseline characteristics were similar except for larger grafts in test patients (3.4 vs 2.7 cm2; P = .004) and higher body mass index (BMI) in control patients (27.8 vs 24.9 kg/m2; P = .01). Failure rates, final patient-reported outcome (PRO) scores, and PRO score changes from baseline were compared between the cohorts. Multiple regression was used to control for potential confounders and investigate noninferiority using minimal clinically important differences (MCIDs). Results: The mean follow-up was 2 years (range, 1-5 years) in both cohorts. Both cohorts showed significant improvement in all PRO scores, with no significant between-group differences in failure rates, final PRO scores, or PRO changes from baseline. There were 3 cases of failure in each cohort (control cohort: allograft revision [n = 2], debridement [n = 1]; test cohort: chondroplasty [n = 2], conversion to total knee arthroplasty [n = 1]). Regression analysis showed that adjusted differences in final PRO scores based on weightbearing protocol were minor and less than MCIDs when controlling for age, sex, graft size, BMI, and allograft location. Analysis of the MCIDs with respect to the lower bounds of the confidence intervals indicated that WBAT was noninferior to TTWB with a reasonable degree of confidence (range, 84.1%-99.9% confidence). Conclusion: Results indicated that immediate unrestricted WBAT after OCA transplantation to the distal femur was equally safe and effective compared to restricted TTWB.

In vivo MRI of fresh stored osteochondral allograft transplantation with delayed gadolinium-enhanced MRI of cartilage: protocol considerations and recommendations.

The protocol for delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) was adapted for the evaluation of transplanted osteochondral allograft cartilage. Eight patients with focal grade 4 cartilage defects of the femoral condyle were treated with single cylindrical osteochondral allografts. At 1 and 2 years, dGEMRIC image sequences were acquired and regions of interest (ROIs) were drawn in repair and native control cartilage. Mean T1 values of region of interest were used to calculate established dGEMRIC metrics. The correlation was measured between the ΔR1 and R1 -Post metrics for repair and native cartilage. T1 times were measured in deep and superficial zones of cartilage. A strong correlation was identified between full-thickness, deep, and superficial ΔR1 and R1 -Post values for native cartilage and repair cartilage for all years (range: 0.893-1.0). The mean T1 times and ΔR1 rate between deep and superficial regions of articular cartilage were statistically different for all regions of the distal femora analyzed at 1 year and 2 years after osteochondral allograft transplantation (P<0.05). The dGEMRIC pre-Gadolinium scan is unnecessary when evaluating transplanted osteochondral allograft cartilage. The observation of stratified T1 and ΔR1 values indicates a need to re-evaluate the methodology behind the placement of region of interest in dGEMRIC.

Prospective, multi-center, pilot study to evaluate symptom relief in patients with medial knee osteoarthritis (OA) treated with the KineSpring® knee implant for load reduction - the SOAR protocol.

The study described here is designed as a prospective, multicenter, open-label, single-arm pilot study. Eligible subjects with symptomatic osteoarthritis of the medial compartment of the knee will be enrolled in the study and will receive the KineSpring® Knee Implant System. The study population will consist of adult patients between 25 and 80 years of age that have been diagnosed with medial knee osteoarthritis and have failed to improve after at least 6 months of conservative medical treatment. A patient is considered to have a clinically important change in OA pain and function with a minimum improvement of 20% compared to baseline measures. We will collect data on the safety and effectiveness of the KineSpring in patients with primarily unicompartmental medial knee osteoarthritis through 24 months of postoperative follow-up. These data will provide insights on the overall clinical success and safety outcome of KineSpring System.

Avascular necrosis of the proximal humerus: a novel indication for the use of osteochondral allograft transplantation in the shoulder: Case report.

Osteochondral allograft (OCA) transplantation is an increasingly available biologic treatment option for a range of intraarticular aetiologies. To our knowledge, no prior publication has documented the use of this technology to treat a lesion of the proximal humerus secondary to avascular necrosis (AVN). We describe our experience treating a 42-year-old female executive with idiopathic AVN of the proximal humerus with a fresh osteochondral allograft. Computed tomography (CT) at 3 months post-op showed full bony incorporation and a restored native joint contour. Over the initial 7 months post-operatively, she reported continued improvements in pain and function as measured by quick Disabilities of the Arm, Shoulder, and Hand (DASH) scores. She was discharged from physical therapy after 6 months, reporting no rest pain, full active and passive range of motion, and unrestricted occupational and recreational activity.

Osteochondral Allograft Transplantation in the Shoulder: A Systematic Review of Indications and Outcomes.

OBJECTIVE: To collate current literature pertaining to the published reports of indications for, and outcomes of, osteochondral allograft (OCA) transplantations in the shoulder so as to guide surgeons in the management of various etiologies of osteochondral lesions in this joint. DESIGN: A systematic review of the current literature was performed in February 2022 in the PubMed, Cochrane, and EMBASE databases using specific search terms and predetermined inclusion/exclusion criteria. RESULTS: One-hundred-twenty-three articles were initially identified, 30 full-text articles were assessed for eligibility, and 17 articles met inclusion criteria. Data were collected for study characteristics, etiology, lesion size/location, intervention/type of graft used, follow-up, and outcomes. In total, 83 shoulders were included (n = 83) in the review with an average follow-up of 45.7 months. Nine specific indications for OCA transplantation in the shoulder included: reverse Hill-Sachs lesions (33), Hill-Sachs lesions (22), pain pump chondrolysis (10), recurrent shoulder instability (7), osteoarthritis/degenerative changes (5), radiofrequency chondrolysis (2), prominent suture anchors (2), glenoid lesion (1), and osteochondritis dissecans (1). Seventeen patients had concomitant surgeries and two patients were lost to follow-up. Of the total 83 shoulders, 68 had favorable outcomes and 13 had unfavorable outcomes as determined by graft incorporation, pain scores, functionality/ROM, patient-reported satisfaction, and/or requirement for revision/arthroplasty. Of the 13 with unfavorable outcomes, a disproportionate number had concomitant surgeries and/or were performed for pain pump chondrolysis (6). CONCLUSIONS: The use of OCAs appears to be a viable option for a variety of difficult-to-treat shoulder pathologies, particularly those characterized by isolated osteochondral injuries.

Implantable Shock Absorber Provides Superior Pain Relief and Functional Improvement Compared With High Tibial Osteotomy in Patients with Mild-to-Moderate Medial Knee Osteoarthritis: A 2-Year Report.

OBJECTIVE: Up to 10 million Americans below the age of 65 years have symptomatic knee osteoarthritis (OA) and may not yet be candidates for arthroplasty. In response, a subcutaneous implantable shock absorber (ISA) that unloads the knee has been developed. The safety and effectiveness of ISA treatment were compared against a surgical unloading control, high tibial osteotomy (HTO). DESIGN: This was a prospective open-label cohort study with a historical control arm. Subjects underwent ISA placement or HTO. The primary endpoint was a composite variable combining pain, function, specific adverse events, integrity of implant or hardware, and conversion to subsequent surgery. Pain and function outcomes (Western Ontario and McMaster Universities Arthritis Index scores) were assessed through 24 months. Adverse events were tracked. RESULTS: The primary endpoint demonstrated superiority of the ISA arm versus the HTO arm, with 85.6% of ISA subjects meeting all criteria compared with 65.5% of HTO subjects. In addition, all 5 secondary endpoints showed superiority of ISA over HTO. At 24 months, the proportions of subjects considered responders were 95.8% (ISA) versus 87.9% (HTO) for pain and 91.7% (ISA) versus 81.3% (HTO) for function. The ISA procedure was well tolerated, with 13.4 days to full weightbearing status versus 58.0 days for the HTO arm. CONCLUSIONS: Treatment with an ISA demonstrated noninferiority and superiority versus treatment with HTO in subjects aged 25-65 years who had OA of the medial knee. Treatment with ISA has high clinical benefit and is durable through at least 24 months.

Signal polarity restoration in a 3D inversion recovery sequence used with delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC).

PURPOSE: To develop an image reconstruction algorithm that restores the signal polarity in a three-dimensional inversion-recovery (3D-IR) sequence used in delayed gadolinium-enhanced MRI of cartilage (dGEMRIC). This approach effectively doubles the dynamic range of data used for T1 curve fitting. MATERIALS AND METHODS: We applied this reconstruction algorithm to a 3D-IR TFE sequence used for T1 mapping, validated the technique in a phantom study, and performed T1-map calculations in postosteochondral allograft transplant (OAT) patients. In addition, we performed a signal simulation study to assess the algorithm's capability to reduce the number of inversion times used in the 3D-IR TFE sequence. RESULTS: In comparison to a standard T1-mapping algorithm that uses the magnitude of the MRI signal, the proposed algorithm improves the reliability of T1 relaxation fits to the inversion-recovery three-parameter function. The signal simulation study shows that the number of TI inversion times can be reduced to as few as four, without compromising the accuracy of T1 calculations. CONCLUSION: This algorithm can be applied to any 2D- or 3D-IR acquisition sequence used in conjunction with dGEMRIC. Application of the algorithm improves the reliability of T1 calculations and allows the number of TIs to be reduced, leading to shorter scan times in dGEMRIC.

Marrow Stimulation Has Relatively Inferior Patient-Reported Outcomes in Cartilage Restoration Surgery of the Knee: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Multiple cartilage repair techniques are available for chondral defects in the knee. Optimal treatment is controversial. PURPOSE: To evaluate change from baseline in the 5 Knee injury and Osteoarthritis Outcome Score (KOOS) subscales among different cartilage repair techniques of the knee. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 1A. METHODS: Medline and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for randomized controlled trials with minimum 1 year follow-up reporting change from baseline KOOS (delta KOOS) subscale values. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. A meta-analysis was performed on the following surgery types: microfracture (Mfx); augmented microfracture techniques (Mfx+Augment); and culture-based therapies, including autologous chondrocyte implantation (ACI) and matrix-assisted autologous chondrocyte implantation (MACI). A random-effects metaregression model was used. RESULTS: A total of 14 randomized trials with a total of 775 patients were included. The KOOS Sport and Recreation (Sport) and KOOS Quality of Life (QOL) were the 2 most responsive subscales after operative intervention. Outcomes from Mfx and Mfx+Augment were not different in any of the 5 KOOS subscales (minimum P > .3). The mean delta KOOS Sport after ACI/MACI was 9.9 points greater than after Mfx (P = .021) and 11.7 points greater than after Mfx+Augment (P = .027). Longer follow-up time correlated with greater delta KOOS Sport (P = .028). Larger body mass index led to greater delta KOOS QOL (P = .045). Larger cartilage defect size correlated with greater delta KOOS Pain and KOOS Activities of Daily Living scores (P = .023 and P = .002, respectively). CONCLUSION: The KOOS Sport and QOL were the most responsive subscales after cartilage restoration surgery of the knee. Culture-based therapies (ACI/MACI) led to clinically relevant improvements in the KOOS Sport score compared with marrow stimulation and may be a more appropriate treatment in younger and more active individuals. There were no benefits to Mfx+Augment over Mfx alone in any of the KOOS subscales.

Inconsistent Reporting of Preauthorization Medical Criteria for Osteochondral Allograft Transplantation Surgery.

BACKGROUND: Although osteochondral allograft (OCA) transplantation has been a standard treatment for patients with osteochondral lesions, there is a disagreement in commercial payers' medical criteria regarding the definition of medical suitability and thus authorization for OCA transplantation. The primary goal of this study was to understand where consensus between a committee of experienced cartilage restoration surgeon scientists and payer policies existed and where there was significant disagreement. METHODS: U.S. private payers were identified by reviewing health insurance market research literature. Medical criteria were then obtained from publicly available payer medical polices. A literature review was conducted to identify supporting evidence for consensus statements based on private payer medical criteria. The MOCA (Metrics of Osteochondral Allograft) Committee, 30 experienced surgeons and subject-matter experts in OCA transplantation, used a Likert scale of 1 (strongly disagree) to 5 (strongly agree) to rank each statement. The extent of agreement and disagreement among participants was measured for each statement. Consensus was defined as agreement or disagreement of >75%. RESULTS: Fifty-seven statements regarding relevant medical criteria for OCA transplantation were included in the survey. All 30 MOCA Committee members completed the survey (100% response rate). Over half of the statements (52.6%) did not reach consensus. Of the remaining 27 statements that reached consensus, respondents agreed or strongly agreed with 16 statements, and disagreed or strongly disagreed with 11 statements. Inconsistent voting was observed for statements related to osteoarthritis, inflammation, and degenerative changes. CONCLUSIONS: Commercial payers are not consistent in the medical criteria used to define patient eligibility for authorization of OCA transplantation. In contrast, an expert panel of cartilage surgeons reached a consensus that OCA transplantation was clearly suitable for a variety of specific indications. This study demonstrates the need to standardize medical criteria for cartilage restoration based on the most current literature, as well as in conjunction with experienced cartilage restoration experts. LEVEL OF EVIDENCE: Therapeutic Level V . See Instructions for Authors for a complete description of levels of evidence.

Variability in Private Payer Medical Policies for Osteochondral Allograft Transplantation Demonstrates the Absence of Standardization in Medical Criteria Between Payers.

Purpose: To define the criteria for coverage for a cartilage restoration procedure and osteochondral allograft (OCA) transplantation and to investigate coverage for OCA procedures among private payer medical policies. Methods: A systematic search of private payer websites was conducted to identify publicly available 2018 OCA medical policies. Medical criteria related to patient demographics, defect characteristics, and previous treatment were analyzed. Trends in coverage for treatment of talus and patella and the extent of restrictiveness of medical policies were evaluated from 2016 to 2018. The extent of restrictiveness of a policy was defined by number of medical criteria established by payer policies. Policies with >5, 3-5, and <3 specified criteria for OCAs were considered strongly, moderately, and weakly restrictive, respectively. Results: In total, 49 private payer medical policies for OCA transplantation were identified. Extracted criteria varied greatly between medical policies. Ten different defect size ranges were reported across payer policies. Criteria for patient body mass index was specified in 63% of policies. Criteria for failed arthroscopic or traditional surgical procedure were identified in 20% of the policies. More than one half of policies (51%) specified knee defect location to load-bearing surfaces. Analysis of trends in positive coverage statements and restrictiveness showed an increase from 4.7% in 2016 to 39.5% for talus, 4.7% to 7.0% for patella, and a slight shift (4.7% of payers) toward weakly restrictive medical policies. Conclusions: This study demonstrates wide variability and inconsistencies in published criteria among OCA medical policies. Clinical Relevance: This study informs clinicians of the current state of coverage for OCA transplantation, providing insights into the variability of payer policies and potential impact.

Evaluation of Osseous Incorporation After Osteochondral Allograft Transplantation: Correlation of Computed Tomography Parameters With Patient-Reported Outcomes.

BACKGROUND: Studies have reported favorable clinical outcomes after osteochondral allograft (OCA) transplantation to treat osteochondral defects and have demonstrated that healing of the osseous component may be critical to outcomes. However, there is currently no consensus on the optimal modality to evaluate osseous healing. PURPOSE: To define parameters for OCA healing using computed tomography (CT) and to investigate whether osseous healing identified using CT is correlated with improved pain and function on patient-reported outcomes (PROs) collected closest in time to the postoperative CT scan and at final follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Of 118 patients who underwent OCA transplantation for articular cartilage defects of the knee over the 10-year study period, 60 were included in final analysis based on completion of CT scans at 5.8 ± 1.9 months postoperatively and PROs collected preoperatively and postoperatively. CT parameters, including osseous incorporation, bone density, subchondral bone congruency, and cystic changes, were summarized for each patient relative to the cohort. Parameters were assessed for inter- and intrarater reliability as well as for covariation with patient characteristics and surgical variables. Structural equation modeling was used to assess correlation of CT parameters with change in PROs from preoperatively to those collected closest in time to CT acquisition and at the final follow-up. RESULTS: Bone incorporation was the most reliable CT parameter. The summarized scores for CT scans were normally distributed across the study population. Variance in CT parameters was independent of age, sex, body mass index, prior surgery, number of grafts, lesion size, and location. No significant correlation (P > .12 across all comparisons) was identified for any combination of CT parameter and change in PROs from baseline for outcomes collected either closest to CT acquisition or at the final follow-up (mean, 38.2 ± 19.9 months; range, 11.6-84.9 months). There was a uniformly positive association between change in PROs and host bone density but not graft bone density, independent of patient characteristics and surgical factors. CONCLUSION: CT parameters were independent of clinical or patient variables within the study population, and osseous incorporation was the most reliable CT parameter. Metrics collected from a single postoperative CT scan was not correlated with clinical outcomes at ≥6-month longitudinal follow-up.

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.

Osteochondritis Dissecans of the Knee: Etiology and Pathogenetic Mechanisms. A Systematic Review.

OBJECTIVE: The purpose of this manuscript is to analyze the evidence regarding etiopathogenesis of knee osteochondritis dissecans (OCD) lesions through a systematic review, so to summate the current understanding of the origin and progression of this pathologic articular processes. DESIGN: A systematic review of the literature was performed on the PubMed and Cochrane databases on October 2017 by 2 independent authors and included all levels of evidence. This included all English language literature, pertaining specifically to etiopathology of knee OCD with exclusions for review articles and expert opinion. Of 965 identified records, 154 full-text articles were assessed for eligibility and 86 studies met the inclusion criteria. RESULTS: According to these studies, the etiology of OCD can be of a biological or mechanical origin: 40 articles proposed a biological hypothesis, including genetic causes (27), ossification center deficit (12), and endocrine disorders (9); conversely, 52 articles supported a mechanical hypothesis, including injury/overuse (18), tibial spine impingement (5), discoid meniscus (16), and biomechanical alterations (20) as the cause of the onset of OCD. The pathogenic processes were investigated by 36 of these articles, with a focus on subchondral bone fracture and ischemia as the ultimate events leading to OCD. CONCLUSIONS: Biological and mechanical factors are found to result in subchondral bone remodeling alterations, acting independently or more likely synergically in the progression of knee OCD. The former includes genetic causes, deficit of ossification centers and endocrine disorders; the latter, tibial spine impingement, discoid meniscus, and biomechanical alterations, together with injuries and overuse. The resultant subchondral bone ischemia and/or fracturing appears to determine the onset and progression of OCD. LEVEL OF EVIDENCE: Systematic review of level II-IV studies, level IV.

An Expert Consensus Statement on the Management of Large Chondral and Osteochondral Defects in the Patellofemoral Joint.

BACKGROUND: Cartilage lesions of the patellofemoral joint constitute a frequent abnormality. Patellofemoral conditions are challenging to treat because of complex biomechanics and morphology. PURPOSE: To develop a consensus statement on the functional anatomy, indications, donor graft considerations, surgical treatment, and rehabilitation for the management of large chondral and osteochondral defects in the patellofemoral joint using a modified Delphi technique. STUDY DESIGN: Consensus statement. METHODS: A working group of 4 persons generated a list of statements related to the functional anatomy, indications, donor graft considerations, surgical treatment, and rehabilitation for the management of large chondral and osteochondral defects in the patellofemoral joint to form the basis of an initial survey for rating by a group of experts. The Metrics of Osteochondral Allografts (MOCA) expert group (composed of 28 high-volume cartilage experts) was surveyed on 3 occasions to establish a consensus on the statements. In addition to assessing agreement for each included statement, experts were invited to propose additional statements for inclusion or to suggest modifications of existing statements with each round. Predefined criteria were used to refine statement lists after each survey round. Statements reaching a consensus in round 3 were included within the final consensus document. RESULTS: A total of 28 experts (100% response rate) completed 3 rounds of surveys. After 3 rounds, 36 statements achieved a consensus, with over 75% agreement and less than 20% disagreement. A consensus was reached in 100.00% of the statements relating to functional anatomy of the patellofemoral joint, 88.24% relating to surgical indications, 100.00% relating to surgical technical aspects, and 100.00% relating to rehabilitation, with an overall consensus of 95.5%. CONCLUSION: This study established a strong expert consensus document relating to the functional anatomy, surgical indications, donor graft considerations for osteochondral allografts, surgical technical aspects, and rehabilitation concepts for the management of large chondral and osteochondral defects in the patellofemoral joint. Further research is required to clinically validate the established consensus statements and better understand the precise indications for surgery as well as which techniques and graft processing/preparation methods should be used based on patient- and lesion-specific factors.

Subtalar release in clubfeet: a retrospective study of 10-year outcomes.

BACKGROUND: Optimal management of congenital talipes equinovarus continues to be controversial. There is a dramatically renewed emphasis on non-operative management partly because there has been a high recurrence rate among operated feet. Our hypothesis is that early, extensive subtalar ligament release as the cornerstone of aggressive hindfoot realignment prevents recurrence and retains mobility. MATERIALS AND METHODS: Twenty-two congenital clubfeet (14 patients) corrected by one surgeon were evaluated using two validated patient-based outcome instruments, dynamic pedobarographic analysis, hindfoot mobility, and weightbearing radiographs. Pedobarographic analysis consisted of quantifying peak plantar forces and pressures during the gait cycle in 22 corrected feet and 24 control feet using the FSCAN in-shoe device. RESULTS: The mean age at surgery was 8 months and mean followup was 10 years. No patients experienced recurrence of deformity. Reported foot function and satisfaction were very high for all patients and were comparable to reported normal population values. AP and lateral talocalcaneal angles for each foot were within normal limits for age. Hindfoot range of motion, including dorsiflexion, was preserved in all feet. Peak regional forces throughout the gait cycle and plantar pressures at foot flat were mildly, but statistically significantly, higher in the midfoot of corrected feet suggesting slight flattening of the arch. One patient had tendon transfers for bilateral calcaneal deformity and one patient had surgical correction of a bilateral valgus deformity. CONCLUSION: Aggressive hindfoot realignment provides definitive treatment of an equinovarus deformity, but care must be taken to avoid overcorrection.