SLR - September 2018 - Ashley T. Bittar

Effect of the Containment Type on Clinical Outcomes in Osteochondral Lesions of the Talus Treated with Autologous Osteochondral Transplantation

Reference: Shimozono, Y., Donders, J. C., Yasui, Y., Hurley, E. T., Deyer, T. W., Nguyen, J. T., Kennedy, J. G. Effect of the Containment Type on Clinical Outcomes in Osteochondral Lesions of the Talus Treated with Autologous Osteochondral Transplantation. Am J Sports Med. 2018 Jun 5; 46(9), 2096–2102.

Scientific Literature Review

Reviewed By: Ashley T. Bittar, DPM
Residency Program: Montefiore Medical Center, Bronx, NY

Podiatric Relevance:
Autologous osteochondral transplantation (AOT) and osteochondral allograft transplantation procedures are typically utilized for large osteochondral lesions of the talus (OLTs) or lesions with subchondral cysts. Predictors of the outcomes of AOT have been established as body mass index and the requirement for greater than two grafts. While it has been shown that larger uncontained-type OLTs respond well with AOT, no study has reported on the prognostic significance of contained-type osteochondral lesions treated with the AOT procedure. The purpose of this study was to determine the effect of the containment of OLTs on clinical and radiological outcomes in patients who underwent AOT for OLTs.

Methods: This is a retrospective cohort study comparing patients with contained-type and uncontained-type OLTs of all patients who underwent AOT for the treatment of OLTs between 2006 and 2014. AOT was indicated for the patients whose lesion size was greater than 10 mm as well as revision procedures for failed bone marrow stimulation (BMS) and/or cystic lesions. All patients undergoing AOT were divided into the contained-type group (cartilage defect that had surrounding articular cartilage) or uncontained-type group (cartilage defect that did not have a peripheral cartilage border on one side with loss of medial or lateral articular buttress) based on preoperative MRI. Clinical outcomes were evaluated using the Foot and Ankle Outcome Score (FAOS) pain subscale and the 12-Item Short Form Health Survey (SF-12) physical component summary. Postoperative MRI was carried out after the AOT procedure in all patients to assess the cartilage, and presence of cysts.

Results: Of the 94 patients who were included in the study, 63 patients had an uncontained-type OLT, and 31 had a contained-type OLT. The median FAOS scores improved significantly after surgery in both contained-type and uncontained-type lesions. There were no significant differences in postoperative SF-12 and MOCART scores between contained-type and uncontained-type OLTs. Multivariant regression models showed that patients with contained-type OLTs had an approximately 10-point better score on the FAOS compared with uncontained-type OLTs. Patients who underwent previous microfracture had worse postoperative FAOS scores than those who did not undergo previous microfractures. The rate of cystic occurrence in uncontained-type OLTs was higher than that of contained-type OLTs, but no statistical significance was found.

Conclusion: The authors conclude that the AOT procedure provided better clinical and MRI outcomes in contained-type OLTs. They were also able to show that previous BMS was a negative prognostic factor for outcomes for those with both contained-type and uncontained-type lesions. This may be important when discussing possible surgical treatments for OLTs with patients and expectant results. There were many limitations to this study, including the retrospective nature, no validated scoring system for OLTs and patients who had adjunctive procedures, such as lateral ankle ligament reconstruction or debridement for anterior ankle impingement, were included in this study. 

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