Prognostic significance of the containment and location of osteochondral lesions of the talus: independent adverse outcomes associated with uncontained lesions of the talar shoulder.

BACKGROUND: Uncontained osteochondral lesions of the talar shoulder are associated with an increased risk of clinical failure in patients treated with current cylindrical osteochondral autograft techniques. Whether the same holds true in patients undergoing arthroscopic treatment is unknown.

PURPOSE: To determine the relative prognostic significance of the containment (shoulder vs nonshoulder type) and location (medial vs lateral) of an osteochondral lesion of the talus (OLT).

HYPOTHESIS: Arthroscopic treatment may not be ideal for uncontained lesions of the talar shoulder due to a lack of structural support.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: Arthroscopic treatment for OLT was performed on the ankles of 399 patients between 2001 and 2009. Analyses were performed by grouping the patients according to type of containment (shoulder, n = 181; nonshoulder, n = 218), location (medial, n = 274; lateral, n = 125), and both type of containment and location (medial shoulder, n = 129; medial nonshoulder, n = 145; lateral shoulder, n = 52; lateral nonshoulder, n = 73). To evaluate the role of containment and location independently of OLT size, patients were grouped according to quartile of defect size, and outcomes were analyzed within each group.

RESULTS: Patients with shoulder-type OLT had a substantially worse clinical outcome than did those with nonshoulder-type OLT, even after adjustment for OLT size (P < .05). However, there was no significant difference in clinical outcome between patients with medial OLT and those with lateral OLT, and the clinical failure rates of the 2 groups were similar (P > .05). A Cox proportional hazards regression model demonstrated that OLT containment, but not location, exerted an independent prognostic effect.

CONCLUSION: Patients with uncontained OLT of the talar shoulder experienced a more complicated clinical outcome than did those with contained, nonshoulder-type OLT even after adjustment for OLT size and regardless of location.