All-arthroscopic AMIC® (AT-AMIC) for the treatment of talar osteochondral defects: A short follow-up case series

The Frequency and Severity of Complications in Surgical Treatment of Osteochondral Lesions of the Talus: A Systematic Review and Meta-Analysis of 6,962 Lesions

OBJECTIVE

The primary aim was to determine and compare the complication rate of different surgical treatment options for osteochondral lesions of the talus (OLTs). The secondary aim was to analyze and compare the severity and types of complications.

DESIGN

A literature search was performed in MEDLINE (PubMed), EMBASE (Ovid), and the Cochrane Library. Methodological quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS). Primary outcome was the complication rate per surgical treatment option. Secondary outcomes included the severity (using the Modified Clavien-Dindo-Sink Complication Classification System for Orthopedic Surgery) and types of complications. The primary outcome, the severity, and the sub-analyses were analyzed using a random effects model. A moderator test for subgroup-analysis was used to determine differences. The types of complications were presented as rates.

RESULTS

In all, 178 articles from the literature search were included for analysis, comprising 6,962 OLTs with a pooled mean age of 35.5 years and follow-up of 46.3 months. Methodological quality was fair. The overall complication rate was 5% (4%-6%; treatment group effect, P = 0.0015). Analysis resulted in rates from 3% (2%-4%) for matrix-assisted bone marrow stimulation to 15% (5%-35%) for metal implants. Nerve injury was the most observed complication.

CONCLUSIONS

In 1 out of 20 patients treated surgically for an OLT, a complication occurs. Metal implants have a significantly higher complication rate compared with other treatment modalities. No life-threatening complications were reported.

Typical Complications After Cartilage Repair of the Ankle Using Autologous Matrix-Induced Chondrogenesis (AMIC)

Background:

Autologous matrix-induced chondrogenesis (AMIC) for the treatment of osteochondral lesions of the talus (OLT) results in favorable clinical outcomes, yet high reoperation rates. The aim of this study was to report and analyze typical complications and their risk factors after AMIC for OLT.

Methods:

A total of 127 consecutive patients with 130 AMIC procedures for OLT were retrospectively assessed. All AMIC procedures were performed in an open fashion with 106 (81.5%) cases requiring a malleolar osteotomy (OT) to access the OLT. Seventy-one patients (54.6%) underwent subsequent surgery. These cases were evaluated at a mean follow-up of 3.1 years (±2.5) for complications reviewing postoperative imaging and intraoperative findings during revision surgery. Six patients (8.5%) were lost to follow-up. Regression model analysis was conducted to identify factors that were associated with AMIC-related complications.

Results:

Among the 65 (50%) patients who required revision surgery, 18 patients (28%) demonstrated AMIC-related complications with deep fissuring (83%) and thinning (17%) of the AMIC graft. Conversely, 47 patients (72%) underwent subsequent surgery due to AMIC-unrelated reasons including isolated removal of symptomatic hardware (n = 17) and surgery addressing concomitant pathologies with (n = 25) and without hardware removal (n = 5). Previous prior cartilage repair surgery was significantly associated with AMIC graft-associated complications in patients undergoing revision surgery ( P = .0023). Among age, body mass index, defect size, smoking, and bone grafting, smoking was the only factor showing statistical significance with an odds ratio of 3.7 (95% CI 1.24, 10.9; P = .019) to undergo revision surgery due to graft-related complications, when adjusted for previous cartilage repair surgery.

Conclusion:

The majority of revision surgeries after AMIC for OLT are unrelated to the performed AMIC graft but frequently address symptomatic hardware and concomitant pathologies. Both smoking and previous cartilage repair surgery seem to significantly increase the risk of undergoing revision surgery due to AMIC-related complications.

Level of evidence:

Level IV, case series.

Autologous matrix induced chondrogenesis plus peripheral blood concentrate (AMIC+PBC) in chondral lesions at the ankle as part of a complex surgical approach - 5-year follow-up

BACKGROUND

The aim of the study was to assess 5-year-follow-up (5FU) after Autologous Matrix Induced Chondrogenesis plus Peripheral Blood Concentrate (AMIC+PBC) in chondral lesions at the ankle as part of a complex surgical approach.

METHODS

In a prospective consecutive non-controlled clinical follow-up study, all patients with chondral lesion at the ankle treated with AMIC+PBC from July 17, 2016 to May 31, 2017 were included. Size and location of the chondral lesions, the Visual-Analogue-Scale Foot and Ankle (VAS FA) and the EFAS Score before treatment and at 5FU were analysed and compared with previous 2-year-follow-up (2FU). Peripheral Blood Concentrate (PBC) was used to impregnate a collagen I/III matrix (Chondro-Gide, Wolhusen, Switzerland) that was fixed into the chondral lesion with fibrin glue.

RESULTS

One hundred and twenty-nine patients with 136 chondral lesions were included in the study. The chondral lesions were located as follows (n (%)), medial talar shoulder only, 62 (46); lateral talar shoulder only, 42 (31); medial and lateral talar shoulder, 7 (10); tibia, 18 (13). The average for lesion size was 1.8 cm², for VAS FA 45.7 and for EFAS Score 9.8. 2FU/5FU was completed in 105 (81 %)/104(81 %) patients with 112/111 previous chondral lesions. VAS FA improved to 79.8/84.2 and EFAS Score to 20.3/21.5 (2FU/5FU). No parameter significantly differed 2FU and 5FU.

CONCLUSIONS

AMIC+PBC as part of a complex surgical approach led to improved and high validated outcome scores at 2FU/5FU. 2FU and 5FU did not differ.

Prognostic factors for the management of chondral defects of the knee and ankle joint: a systematic review

Purpose

Different surgical techniques to manage cartilage defects are available, including microfracture (MFx), autologous chondrocyte implantation (ACI), osteoarticular auto- or allograft transplantation (OAT), autologous matrix-induced chondrogenesis (AMIC). This study investigated the patient-related prognostic factors on the clinical outcomes of surgically treated knee and ankle cartilage defects.

Methods

This study followed the PRISMA statement. In May 2022, the following databases were accessed: PubMed, Google Scholar, Embase, and Scopus. All the studies investigating the outcomes of surgical management for knee and/or talus chondral defects were accessed. Only studies performing mesenchymal stem cells transplantation, OAT, MFx, ACI, and AMIC were considered. A multiple linear model regression analysis through the Pearson Product–Moment Correlation Coefficient was used.

Results

Data from 184 articles (8905 procedures) were retrieved. Female sex showed a positive moderate association with visual analogue scale at last follow-up (P = 0.02). Patient age had a negative association with the American Orthopaedic Foot and Ankle Score (P = 0.04) and Lysholm Knee Scoring Scale (P = 0.03). BMI was strongly associated with graft hypertrophy (P = 0.01). Greater values of VAS at baseline negatively correlate with lower values of Tegner Activity Scale at last follow-up (P < 0.0001).

Conclusion

The clinical outcomes were mostly related to the patients’ performance status prior surgery. A greater BMI was associated with greater rate of hypertrophy. Female sex and older age evidenced fair influence, while symptom duration prior to the surgical intervention and cartilage defect size evidenced no association with the surgical outcome. Lesion size and symptom duration did not evidence any association with the surgical outcome.

Autologous Matrix-Induced Chondrogenesis (AMIC) for Osteochondral Defects of the Talus: A Systematic Review

Autologous matrix-induced chondrogenesis (AMIC) has been advocated for the management of talar osteochondral lesions (OCLs). This systematic review, which was conducted according to the PRISMA 2020 guidelines, investigated the clinical and imaging efficacy and safety of the AMIC technique in the management of OCLs of the talus. Only studies investigating AMIC for talar chondral defects that were published in peer-reviewed journals were considered. In September 2022, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. Data on the visual analogue scale (VAS), American Orthopaedic Foot and Ankle Score (AOFAS), Tegner activity scale, and Foot Function Index (FFI) were retrieved. To evaluate the morphological MRI findings, data obtained from the magnetic resonance observation of cartilage repair tissue (MOCART) scores were evaluated. Data on hypertrophy, failures, and revision surgeries were also collected. Data from 778 patients (39% women, 61% men) were collected. The mean length of the follow-up was 37.4 ± 16.1 months. The mean age of the patients was 36.4 ± 5.1 years, and the mean BMI was 26.1 ± 1.6 kg/m2. The mean defect size was 2.1 ± 1.9 cm2. Following the AMIC technique, patients demonstrated an improved VAS (p < 0.001), AOFAS (p < 0.001), and FFI (p = 0.02) score. The MOCART score also improved from the baseline (p = 0.03). No difference was observed in the Tegner score (p = 0.08). No graft delamination and hypertrophy were reported in 353 patients. 7.8% (44 of 564) of patients required revision surgeries, and 6.2% (32 of 515) of patients were considered failures. The AMIC technique could be effective in improving symptoms and the function of chondral defects of the talus.

Allograft Versus Autograft Osteochondral Transplant for Chondral Defects of the Talus: Systematic Review and Meta-analysis

BACKGROUND

It is unclear whether the results of osteochondral transplant using autografts or allografts for talar osteochondral defect are equivalent.

PURPOSE

A systematic review of the literature was conducted to compare allografts and autografts in terms of patient-reported outcome measures (PROMs), MRI findings, and complications.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

This study was conducted according to the PRISMA guidelines. The literature search was conducted in February 2021. All studies investigating the outcomes of allograft and/or autograft osteochondral transplant as management for osteochondral defects of the talus were accessed. The outcomes of interest were visual analog scale (VAS) score for pain, American Orthopaedic Foot and Ankle Society (AOFAS) score, and Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Data concerning the rates of failure and revision surgery were also collected. Continuous data were analyzed using the mean difference (MD), whereas binary data were evaluated with the odds ratio (OR) effect measure.

RESULTS

Data from 40 studies (1174 procedures) with a mean follow-up of 46.5 ± 25 months were retrieved. There was comparability concerning the length of follow-up, male to female ratio, mean age, body mass index, defect size, VAS score, and AOFAS score (P > .1) between the groups at baseline. At the last follow-up, the MOCART (MD, 10.5; P = .04) and AOFAS (MD, 4.8; P = .04) scores were better in the autograft group. The VAS score was similar between the 2 groups (P = .4). At the last follow-up, autografts demonstrated lower rate of revision surgery (OR, 7.2; P < .0001) and failure (OR, 5.1; P < .0001).

CONCLUSION

Based on the main findings of the present systematic review, talar osteochondral transplant using allografts was associated with higher rates of failure and revision compared with autografts at midterm follow-up.

Vascularized osteochondral free flaps from the femoral trochlea as versatile procedure for reconstruction of osteochondral lesions of the talus

BACKGROUND

Osteochondral lesions of the talus (OLT) are defects affecting the articular cartilage as well as the subchondral bone, on the lateral shoulder possibly associated with trauma. This study presents the results of reconstructing OLT using vascularized osteochondral flaps from the femoral trochlea.

METHODS

We treated 19 patients with osteochondral talar shoulder defects, using osteochondral flaps from the medial (MFT) or lateral (LFT) femoral trochlea. Functional outcome was evaluated by clinical investigation, visual analogue scale (VAS, 0-10), American Orthopaedic Foot and Ankle Society-Ankle and Hindfoot Scale (AOFAS, 0-100) and The Foot and Ankle Disability Index (FADI, 0-104). Radiographic postoperative follow-up was done by anterior-posterior and lateral X-rays and union of the transferred osteochondral flaps was documented by CT scans.

RESULTS

The osteochondral flaps fused in all of the 19 cases. After a median follow-up of 45.5 months, the patients showed an average FADI of 94.9 and AOFAS-Ankle and Hindfoot Scale of 91.2. All of them were walking free and normal. Subjective median satisfaction was 1.3 in a scale from 1 to 5.

CONCLUSION

Vascularized transfer of osteochondral flaps from the femoral trochlea is a reliable treatment option for symptomatic OLT of the medial and lateral talar edge.

LEVEL OF CLINICAL EVIDENCE

Therapeutic IV.

Autologous matrix induced chondrogenesis (AMIC) as revision procedure for failed AMIC in recurrent symptomatic osteochondral defects of the talus

Autologous matrix induced chondrogenesis (AMIC) is a bone marrow stimulating technique used for the surgical management of chondral defects of the talus. The present study evaluated the clinical outcomes and imaging of AMIC as revision procedure for failed AMIC surgery for osteochondral defects of the talus. Forty-eight patients with symptomatic osteochondral defects who received a revision AMIC were evaluated after a minimum of two years follow-up. Patients with previous procedures rather than AMIC, those who required additional surgical procedures (e.g. ligament repair or deformity correction), or those who had evidence of kissing, bilateral, or multiple lesions were excluded. Outcome parameters included the Visual Analogic Scale (VAS), Tegner Activity Scale, the American Orthopedic Foot and Ankle Score (AOFAS), and the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. All patients were followed by an assessor who was not involved in the clinical management. 27 patients were enrolled in the present study. The mean age of the patient was 34.9 ± 3.1 years, and the mean BMI 27.2 ± 5.1 kg/m². The mean defect surface area was 2.8 ± 1.9 cm². The mean follow-up was 44.3 ± 21.4 months. The mean hospital length of stay was 4.4 ± 1.4 days. At final follow-up, the mean VAS score was 4.1 ± 3.1, the mean Tegner 3.5 ± 1.6, the mean AOFAS 58.8 ± 20.6. The preoperative MOCART score was 22.1 ± 13.7 points, the postoperative MOCART score was 42.3 ± 27.9 points (+ 20.2%; P = 0.04), respectively. 30% (8 of 27 patients) experienced persistent pain and underwent a further chondral procedure. Concluding, AMIC could be a viable option as revision procedure for failed AMIC in recurrent symptomatic osteochondral defects of the talus. The PROMs indicated that patients were moderately satisfied with the procedure, and the MOCART score demonstrated a significant improvement from baseline to the last follow-up. A deeper understanding in prognostic factors and patient selection is critical to prevent failures.

Surgical Management of Focal Chondral Defects of the Talus: A Bayesian Network Meta-analysis

BACKGROUND

No consensus has been reached regarding the optimal surgical treatment for focal chondral defects of the talus.

PURPOSE

A Bayesian network meta-analysis was conducted to compare the clinical scores and complications of mosaicplasty, osteochondral auto- and allograft transplant, microfracture, matrix-assisted autologous chondrocyte transplant, and autologous matrix-induced chondrogenesis (AMIC) for chondral defects of the talus at midterm follow-up.

STUDY DESIGN

Bayesian network meta-analysis; Level of evidence, 4.

METHODS

This Bayesian network meta-analysis followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions. PubMed, Embase, Google Scholar, and Scopus databases were accessed in February 2021. All clinical trials comparing 2 or more surgical interventions for the management of chondral defects of the talus were accessed. The outcomes of interest were visual analog scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, rate of failure, and rate of revision surgery. The network meta-analysis were performed through the routine for Bayesian hierarchical random-effects model analysis. The log odds ratio (LOR) effect measure was used for dichotomous variables, and the standardized mean difference (SMD) was used for continuous variables.

RESULTS

Data from 13 articles (521 procedures) were retrieved. The median length of the follow-up was 47.8 months (range, 31.7-66.8 months). Analysis of variance revealed no difference between the treatment groups at baseline in terms of age, sex, body mass index, AOFAS score, VAS score, and mean number of defects. AMIC demonstrated the greatest AOFAS score (SMD, 11.27) and lowest VAS score (SMD, -2.26) as well as the lowest rates of failure (LOR, 0.94) and revision (LOR, 0.94). The test for overall inconsistency was not significant.

CONCLUSION

At approximately 4 years of follow-up, the AMIC procedure for management of focal chondral defects of the talus produced the best outcome.

AMIC Procedure for Treatment of Osteochondral Lesions of Talus-A Systematic Review of the Current Literature

Osteochondral lesions of talus are a common injury where surgery is indicated in case of failed non-operative treatment or displaced lesions. Many studies have been conducted on the effectiveness of the AMIC procedure. The goal of our study is to create an overview of the current literature. A systematic search adhering to the PRISMA guidelines was conducted in PubMed (MEDLINE) and EMBASE on May 27, 2020. All included studies were evaluated according to the modified Coleman Methodology Score and information on study type, patient numbers, age, follow-up period, grade, location and size of the lesion, study in- and exclusion criteria, associated surgery, surgical technique, scaffold- and fixation technique, postoperative restrictions, reoperation rates, study outcome score, rehabilitation program, and surgical complications was extracted. Ninety-six studies were identified with 18 studies being included in our analysis. The overall quality of the literature was fair with no studies being graded as excellent. Data on preoperative evaluation and surgical technique, complication and reoperation rates, postoperative management and study outcome was extracted in order to create an overview of the current literature. The literature supports the use of the AMIC procedure as an effective treatment for osteochondral lesions of talus. Great heterogeneity exists and comparative studies are missing. While the number of studies on the topic is increasing further are needed and especially with optimized design.

Location Distribution of 2,087 Osteochondral Lesions of the Talus

OBJECTIVE

The primary aim of this study was to evaluate the exact location distribution in patients with osteochondral lesions of the talus (OLTs) using a 9-grid scheme. The secondary aim is to match lesion location to lesion size, arthroscopic or open operation, and trauma occurrence.

METHODS

A systematic review was performed in the databases PubMed, EMBASE, and Cochrane. Search terms consisted of "talus" and "osteochondral lesion." Two independent reviewers evaluated search results and conducted the quality assessment using the Methodological Index for Non-Randomized Studies (MINORS). Primary outcome measure was OLT location in the 9 zone-grid. Secondary outcome measures were OLT size in 9-zones, preoperative radiological modality use, demographic lesion size variables as well as open or arthroscopic treatment.

RESULTS

Fifty-one articles with 2,087 OLTs were included. Heterogeneity concerning methodological nature was observed and methodological quality was low. The posteromedial (28%) and centromedial (31%) zones combined as one location was the location with the highest incidence of OLTs with a rate of 59%. Individual OLT size was reported for only 153 lesions (7%). Preoperative combination of X-ray and magnetic resonance imaging (MRI), and/or computed tomography (CT) was reported in 20 studies (43%). Trauma was reported in 78% of patients. Furthermore, 67% was treated arthroscopically and 76% received primary OLT treatment.

CONCLUSION

The majority of OLTs are located in the posteromedial and centromedial zone, while the largest OLTs were reported in the centrocentral zone. Further research is required to identify the prognostic impact of location occurrence on the outcomes following OLT treatment.

Reliability of the MOCART score: a systematic review

BACKGROUND

The present systematic review analysed the available literature to assess reliability of the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score in the evaluation of knee and ankle osteochondral lesions.

METHODS

All the studies using the MOCART score for knee and/or talus chondral defects were accessed in March 2021. A multivariate analysis was performed to assess associations between the MOCART score at last follow-up and data of patients at baseline, clinical scores and complications. A multiple linear model regression analysis was used.

RESULTS

The MOCART score evidenced no association with patient age (P = 0.6), sex (P = 0.1), body mass index (P = 0.06), defect size (P = 0.9), prior length of symptoms (P = 0.9) or visual analogue scale (P = 0.07). For chondral defects of the knee, no statistically significant association was found between the MOCART score and the International Knee Documentation Committee (P = 0.9) and with the Lysholm Knee Scoring Scales (P = 0.2), Tegner Activity Scale (P = 0.2), visual analogue scale P = 0.07), rate of failure (P = 0.2) and revision (P = 0.9). For chondral defect of the talus, no statistically significant associations were found between the MOCART score and the American Orthopedic Foot and Ankle Score (P = 0.3), Tegner Activity Scale (P = 0.4), visual analogue scale (P = 0.1), rate of failure (P = 0.1) and revision (P = 0.7).

CONCLUSION

The MOCART score demonstrated no association with patient characteristics and with the surgical outcome in patients who underwent surgical management for knee and talus chondral defects.

LEVEL OF EVIDENCE

Level IV.

AMIC for traumatic focal osteochondral defect of the talar shoulder: a 5 years follow-up prospective cohort study

BACKGROUND

Autologous Matrix-Induced Chondrogenesis (AMIC) is addressed to osteochondral defects of the talus. However, evidence concerning the midterm efficacy and safety of AMIC are limited. This study assessed reliability and feasibility of AMIC at 60 months follow-up. We hypothesize that AMIC leads to good clinical outcome at midterm follow-up.

METHODS

Surgeries were approached with an arthrotomy via malleolar osteotomy. A resorbable porcine I/III collagen membrane (Chondro-Gide®, Geistlich Pharma AG, Wolhusen, Switzerland) was used. Patients were followed at 24 and 60 months. The primary outcome of interest was to analyse the Foot Function Index (FFI), and the subscale hindfoot of the American Orthopaedic Foot and Ankle Score (AOFAS). Complications such as failure, revision surgeries, graft delamination, and hypertrophy were also recorded. The secondary outcome of interest was to investigate the association between the clinical outcome and patient characteristics at admission.

RESULTS

Data from 19 patients were included. The mean age at admission was 47.3 ± 13.2 years, and the mean BMI 24.1 ± 4.9 kg/m². 53% (10 of 19 patients) were female. At a mean of 66.2 ± 11.6 months, the FFI decreased at 24-months follow-up of 22.5% (P = 0.003) and of further 1.3% (P = 0.8) at 60-months follow-up. AOFAS increased at 24-months follow-up of 17.2% (P = 0.003) and of further 3.4 (P = 0.2) at 60-months follow-up. There were two symptomatic recurrences within the follow-up in two patients. There was evidence of a strong positive association between FFI and AOFAS at baseline and the same scores last follow-up (P = 0.001 and P = 0.0002, respectively).

CONCLUSION

AMIC enhanced with cancellous bone graft demonstrated efficacy and feasibility for osteochondral defects of the talus at five years follow-up. The greatest improvement was evidenced within the first two years. These results suggest that clinical outcome is influenced by the preoperative status of the ankle. High quality studies involving a larger sample size are required to detect seldom complications and identify prognostic factors leading to better clinical outcome.

LEVEL OF EVIDENCE

II, prospective cohort study.

Matrix-induced autologous chondrocyte implantation versus autologous matrix-induced chondrogenesis for chondral defects of the talus: a systematic review

INTRODUCTION

Chondral defects of the talus are common and their treatment is challenging.

SOURCE OF DATA

Recent published literatures.

AREAS OF AGREEMENT

Membrane-induced Autologous Chondrocyte Implantation (mACI) and Autologous Matrix-Induced Chondrogenesis (AMIC) have been proposed as management for chondral defects of the talus.

AREAS OF CONTROVERSY

It is debated whether AMIC provides greater outcomes compared to mACI for chondral regeneration. Several clinical studies showed controversial results, and the best treatment has not yet been clarified.

GROWING POINTS

To investigate whether AMIC provide superior outcomes than mACI at midterm follow-up.

AREAS TIMELY FOR DEVELOPING RESEARCH

AMIC exhibits similar clinical results to mACI. However, AMIC involves one single surgical procedure, no articular cartilage harvest and hence no morbidity from it, no need for chondrocyte expansion in a separate laboratory setting. For these reasons, AMIC may be preferred to mACI.

Is there clinical evidence to support autologous matrix-induced chondrogenesis (AMIC) for chondral defects in the talus? A systematic review and meta-analysis

BACKGROUND

The aim of this study is to systematically review the literature on clinical outcomes of patients who have undergone autologous matrix-induced chondrogenesis (AMIC) for treatment of osteochondral lesions of the talus (OCL) and compare the studies' outcomes.

METHODS

Pubmed and Embase were searched in January 2020 for articles concerning OCL surgery. Studies were included if they had a minimum 1-year follow-up and the primary measures were functional outcomes. The meta-analysis compared the Visual Analogic Score (VAS), the American Orthopedic Foot and Ankle Score (AOFAS), and the Foot Function Index (FFI) between baseline and follow-up of 1-2years, and 3-5years. A random effects model was used to evaluate outcome changes.

RESULTS

The search returned 15 studies, with a total of 492 patients. The VAS improved 4.45 and 4.6 points from baseline to the 1-2year and 3-5yearfollow-up, respectively (p<0.001). AOFAS improved 31.59 and 32.47 points from baseline to the 1-2year and 3-5yearfollow-up, respectively (p<0.001). The FFI showed a significant improvement of 30.93 points from baseline to year 3-5 (p<0.001). A total of 6 patients with revision surgeries have been reported within the follow up period. It was not possible to correlate clinical features like lesion size, surgical approach, and bone marrow stimulation technique to the reported outcome.

CONCLUSION

Surgical treatment of OCL via the AMIC procedure provided significant improvement in the functional outcome and pain scores when compared to the pre-operative values. Improvements were observed up to 5years post-operatively.

Comparison of clinically used bilayer collagen membrane and trilayer collagen prototype fixation stability in chondral defects at the talus - An experimental human specimen study

BACKGROUND

The purpose of this human specimen experimental study was to compare the fixation stability of clinically used bilayer collagen membrane with fibrin glue with trilayer collagen prototype without fibrin glue in chondral defects at the medial or lateral talar shoulder (both matrices from Geistlich Pharma AG, Wollhusen, Switzerland).

METHODS

Eleven human specimens were used. The membranes were implanted in standardized chondral defects at the medial and lateral talar shoulder randomized. All tests were performed in load-control 15 kg. Range of motion ROM of each ankle was examined individually before testing. The average ROM was 10° dorsiflexion range 0°-20° and 30° plantarflexion range 20°-45°. 1,000 testing cycles with the defined ROM were performed. Two independent investigators, blinded to membrane and fixation type, visually assessed the membrane fixation integrity for peripheral detachment, area of defect uncovered, membrane constitution and delamination.

RESULTS

The clinically used bilayer collagen membrane plus fibrin glue showed higher fixation stability than the trilayer prototype (all p < 0.05). No significant differences occurred between medial and lateral talar shoulder location (all p > 0.05).

CONCLUSIONS

The fixation stability of the trilayer collagen prototype without fibrin glue is lower than of the clinically used bilayer membrane with fibrin glue in chondral defects at the medial and lateral talar shoulder in an experimental human specimen test. Clinical use of trilayer collagen prototype without fibrin glue has to be validated by clinical testing to evaluate if the lower stability of fixation is still sufficient.

Clinical Outcomes of Osteochondral Lesions of the Talus With Large Subchondral Cysts Treated With Osteotomy and Autologous Chondral Grafts: Minimum 2-Year Follow-up and Second-Look Evaluation

Background:

Osteochondral lesions of the talus (OLTs) with large subchondral cysts are challenging to treat.

Purpose:

To determine the safety and efficacy of autologous chondral grafting and malleolus osteotomy for treating OLTs associated with large subchondral cysts.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 19 patients underwent autologous chondral grafting and malleolus osteotomy. We obtained the visual analog scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot, and magnetic resonance observation of cartilage repair tissue (MOCART) scores at 1 and 2 years postoperatively. The International Cartilage Repair Society (ICRS) score was collected 2 years postoperatively during second-look arthroscopic surgery.

Results:

In all patients, the osteotomy site healed without nonunion or malunion. Only 1 patient developed joint space narrowing. No donor site complications occurred. The mean AOFAS score significantly improved at 1 year (from 72.8 ± 4.8 preoperatively to 93.7 ± 4.6; t = –13.708; P < .0001). The 1- and 2-year AOFAS scores were similar (t = –0.755; P = .455), indicating stable improvement. The mean VAS score significantly decreased at 1 year (from 4.68 ± 0.67 preoperatively to 0.47 ± 0.69; t = 18.974; P < .0001). The 1- and 2-year VAS scores were similar (t = –0.705; P = .455), as were the 1- and 2-year MOCART scores (64.2 ± 7.5 vs 67.4 ± 7.3, respectively; t = –1.312; P = .198). The ICRS scores were as follows: 7 points (abnormal) in 1 (5.2%) patient, 8 to 11 points (nearly normal) in 9 (47.4%) patients, and 12 points (normal) in 9 (47.4%) patients.

Conclusion:

Osteotomy combined with autologous osteochondral transplantation provided good functional outcomes in patients with OLTs and large subchondral cysts. Second-look arthroscopic surgery showed healthy cartilage healing.

Autologous Matrix-Induced Chondrogenesis for Osteochondral Lesions of the Talus: A Clinical and Radiological 2- to 8-Year Follow-up Study

BACKGROUND

Autologous matrix-induced chondrogenesis (AMIC) has become an interesting treatment option for osteochondral lesions of the talus (OLTs) with promising clinical short- to midterm results.

PURPOSE

To investigate the clinical and radiological outcome of the AMIC procedure for OLTs, extending the follow-up to 8 years.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Thirty-three patients (mean age, 35.1 years; body mass index, 26.8) with osteochondral lesions of the medial talar dome were retrospectively evaluated after open AMIC repair at a mean follow-up of 4.7 years (range, 2.3-8.0 years). Patients requiring additional surgical procedures were excluded. All OLTs (mean size, 0.9 cm²; range, 0.4-2.3 cm²) were approached through a medial malleolar osteotomy, and 28 patients received subchondral autologous bone grafting. Data analysis included the visual analog scale for pain, the American Orthopaedic Foot and Ankle Society score for ankle function, the Tegner score for sports activity, and the MOCART (magnetic resonance observation of cartilage repair tissue) scoring system for repair cartilage and subchondral bone evaluation.

RESULTS

Mean ± SD visual analog scale score improved significantly from 6.4 ± 1.9 preoperatively to 1.4 ± 2.0 at latest follow-up ( P < .001). The mean American Orthopaedic Foot and Ankle Society score was 93.0 ± 7.5 (range, 75-100). The Tegner score improved significantly from 3.5 ± 1.8 preoperatively to 5.2 ± 1.7 at latest follow-up ( P < .001), and 79% returned to their previous sports levels. The MOCART score averaged 60.6 ± 21.2 (range, 0-100). Complete filling of the defect was seen in 88% of cases, but 52% showed hypertrophy of the cartilage layer. All but 1 patient showed persistent subchondral bone edema. The patient's age and body mass index, the size of the osteochondral lesion, and the MOCART score did not show significant correlation with the clinical outcome. There were no cases of revision surgery for failed AMIC. Fifty-eight percent underwent reoperation, mainly for symptomatic hardware after malleolar osteotomy.

CONCLUSION

AMIC for osteochondral talar lesions led to significant pain reduction, recovery of ankle function, and successful return to sport. The MOCART score did not correlate with the good clinical results; the interpretation of postoperative imaging remains therefore challenging.