Primary Modified Broström Procedure Shows Superior Outcome to Revision to Lateral Ankle Ligament Reconstruction in Patients With Chronic Lateral Ankle Instability at 5-Year Follow-Up.

PURPOSE: To compare the mid-term clinical and radiological outcomes of primary modified Broström procedure (MBP) and revision to lateral ankle ligament reconstruction (LALR) in patients with chronic lateral ankle instability.

METHODS

We retrospectively reviewed all the patients who underwent primary MBP or revision to LALR between November 2005 and March 2020 with minimum follow-up of more than 5 years. Patients with persistent instability despite of rehabilitations underwent surgery. Propensity score matching (1:4) was designed based on age, sex, and body mass index. Clinical assessments included the visual analog scale for pain, American Orthopaedic Foot and Ankle Society scores, Karlsson-Peterson scores, and Foot and Ankle Outcome Scores. Minimally clinically important difference thresholds for visual analog scale and American Orthopaedic Foot and Ankle Society score were calculated cohort-specifically. Radiographic evaluations included the talar tilt test and the anterior drawer test. Arthroscopic findings and intra-articular pathology were evaluated and recorded.

RESULTS

The mean follow-up duration was 107.2 months (range, 60-223). The matched groups showed no significant differences in baseline demographics. There were 663 MBP patients and 44 LALR patients; 176 MBP patients were selected after matching. Intra-articular lesions-synovitis, impingement syndrome, and ossicle formation-were significantly less frequent in the LALR group (P ≤ .042). Preoperative clinical scores were similar between the two groups. However, from 6 months postoperatively, the MBP group had significantly better outcomes in most scores, with more pronounced differences after 1 year. More MBP patients exceeded minimally clinically important difference thresholds than LALR patients for both pain and function (P ≤ .037). There were no significant between-group differences in the radiological outcomes, postoperatively.

CONCLUSIONS

Over a 5-year follow-up period, primary MBP produced better pain relief and functional recovery than revision to LALR, despite a higher frequency of intra-articular lesions, with significantly more MBP patients achieving clinically meaningful improvement (minimally clinically important difference).

LEVEL OF EVIDENCE: Level III, retrospective comparative case series.