Autologous Matrix-Induced Chondrogenesis With Lateral Ligament Stabilization for Osteochondral Lesions of the Talus in Patients with Ankle Instability

SLR - September 2021 - Michelle K. Yoakim

Reference: Ackermann J, Casari FA, Germann C, Weigelt L, Wirth SH, Viehöfer AF. Autologous Matrix-Induced Chondrogenesis With Lateral Ligament Stabilization for Osteochondral Lesions of the Talus in Patients with Ankle Instability. Orthop J Sports Med. 2021; May 14;9(5):23259671211007439.

Level of Evidence: Level III, Retrospective Cohort Study

Scientific Literature Review

Reviewed By: Michelle K. Yoakim, DPM
Residency Program: North Colorado Medical Center – Greeley, CO

Podiatric Relevance: Osteochondral lesions of the talus (OLT) constitute a common sequela of ankle injuries, pose a challenge to adequate treatment, and result in many long-term adverse effects including early osteoarthritis. Many patients presenting with ankle injuries and OLTs also have some degree of lateral ankle instability and require lateral ligament stabilization (LLS). Several treatment protocols have been established for OLTs, including autologous matrix-induced chondrogenesis (AMIC), which has had favorable outcomes. However, while several studies have shown that the presence of instability worsens OLT treatment outcomes, there are currently no studies that include instability as a factor in AMIC treatment outcomes. With the high prevalence of OLTs and ankle instability associated with ankle injuries, podiatrists must understand the factors that affect treatment outcomes. This article compared the clinical and radiographic outcomes in patients with and without concomitant LLS undergoing AMIC for OLT treatment.

Methods: This level three retrospective cohort study took place between April 2010-2018 and included 13 adult patients who underwent AMIC for OLT with LLS for concomitant symptomatic ankle instability and had at least a two-year follow-up period. These patients were matched for age, BMI, lesion size and follow-up to a control group that received isolated AMIC. Surgically, OLTs were accessed through malleolar osteotomies or via direct approach and the AMIC procedure was completed in the standard fashion. Ankle instability was treated with either lateral ligament repair (modified Broström) or anatomic lateral ligament reconstruction (free tendon allograft) based on ATFL & CFL ligament quality. Postoperatively, magnetic resonance observation of cartilage repair tissue (MOCART) 1 and 2.0 scales were utilized for MRI evaluations. American Orthopaedic Foot & Ankle Society score (AOFAS), Cumberland Ankle Instability Tool (CAIT), and Tegner activity scale (pre-injury and pre-surgery) were recorded. Shapiro-Wilk test, t test, Mann-Whitney U test, chi-square, Fisher exact test, Pearson correlation, and the ellipse formula (lesion size) statistical analyses were utilized to compare sociodemographic and clinical characteristics.

Results: Of the intervention patients, 9/13 underwent lateral ligament repair while 4/13 underwent anatomic ligament reconstruction with ligament integrity postoperatively confirmed on MRI. The control group had significantly better clinical outcomes on the AOFAS and Tegner scales. CAIT and AOFAS scores were significantly correlated with intervention patients. Patients with no functional ankle instability had AOFAS scores similar to the control group. MOCART 1 and 2.0 scores demonstrated no statistically significant differences between the groups.

Conclusions: The authors concluded that clinical outcomes were comparable amongst the two groups as long as postoperative ankle stability was achieved. Study limitations include the use of retrospective data lacking preoperative patient-reported outcome measures as well as comparing 2 groups that were treated at different time periods, a lack of CAIT scores for the control group, a lack of homogeneity in operative techniques, and a lack of sufficient power for the MRI analysis. Overall, while this article had several limitations, it did emphasize the need for proper ankle stabilization in patients who present with OLTs as any residual instability after OLT treatment resulted in worse postoperative outcomes.