Presence of Subfibular Ossicle Does Not Affect the Outcome of Arthroscopic Modified Broström Procedure for Chronic Lateral Ankle Instability

Abstract

PURPOSE: To evaluate the clinical and radiological outcomes of the all-inside, arthroscopic, modified Broström procedure (MBP) used to treat chronic lateral ankle instability (CLAI) according to subfibular ossicle (SFO) status. METHODS: Between January 2013 and September 2016, we retrospectively analyzed CLAI patients who underwent the arthroscopic MBP. When performing the arthroscopic MBP, SFO was removed with all inside technique regardless of size. Patients who were not followed for more than a minimum of 12months after surgery were excluded. The patients were divided into 2 groups: ankles with SFOs were assigned to the SFO group and the others to the non-SFO (NSFO) group. The evaluation tools used included the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot score, a pain visual analog scale, and the talar tilt angle. RESULTS: Following the inclusion criteria, we included 125 patients (125 ankles) in this study. The SFO group consisted of 26 patients and the NSFO group consisted of 99 patients. The preoperative scores in the 2 groups shows no significant difference except for AOFAS scores. The final AOFAS scores in both groups improved compared with the preoperative scores (18.4 ± 16.3 and 22.1 ± 21.6 for the SFO and NSFO groups, respectively). The final follow-up visual analog scale scores also improved in both groups (5.0 ± 1.7 and 5.2 ± 1.4, respectively). The mean ± standard deviation talar tilt improved from 8.7 ± 5.0° preoperatively to 4.6 ± 3.6° at the final follow-up in the SFO group, and from 7.3 ± 4.4° preoperatively to 3.2 ± 3.0° at the final follow-up in the NSFO group. Neither the preoperative nor final talar tilt angle differed between the 2 groups (P= .300 and P= .072, respectively). CONCLUSIONS: All-inside arthroscopic MBP after SFO resection was as successful as the same surgery without SFO resection. The clinical outcomes of the SFO and NSFO groups did not differ. Both groups achieved successful radiological outcomes at the last follow-up. All-inside arthroscopic MBP is a reliable treatment for CLAI patients regardless of SFO status. LEVEL OF EVIDENCE: Level III, retrospective comparative study.