Augmented Broström and Improved Functional Outcomes as Measured by PROMIS Scores Compared With Broström Without Augmentation.

BACKGROUND

No study has compared functional outcomes measured by validated Patient-Reported Outcomes Measurement Information System (PROMIS) measures of physical function (PF) and pain interference (PI) between augmented and nonaugmented Broström procedures.

PURPOSE: To determine whether the augmented Broström procedure is associated with improved PROMIS scores compared with the nonaugmented procedure.

STUDY

DESIGN

Cohort study; Level of evidence, 3.

METHODS

All patients who underwent lateral ankle ligament reconstruction at a single institution (2013-2024) were retrospectively reviewed. Revisions, allografts, nonanatomic reconstructions, flexor digitorum longus transfers, progressive collapsing foot deformities, concomitant hindfoot arthrodesis, associated ankle arthroplasties, concomitant fractures, and those without a minimum of 2 years of follow-up were excluded. A total of 97 eligible patients (97 ankles) completed postoperative surveys containing PROMIS and were included for final analysis. Augmentation was performed using the InternalBrace system (Arthrex). Bivariate comparisons of PROMIS were made using t tests. A weighted linear regression model with robust standard errors was fitted to examine associations between PROMIS and the Broström technique, adjusting for clinically relevant covariates. Type-3 analysis of variance was performed to assess the significance of each predictor. Inverse probability of treatment was used to balance the distribution of covariates across techniques.

RESULTS

Of 97 patients, 56 (58%) underwent augmented Broström procedures, and 41 (42%) underwent nonaugmented Broström procedures. In unadjusted comparisons, the augmented type had a higher mean PF (51.2 ± 8.5 vs 48.5 ± 9.4; P = .16) and a lower PI (49.3 ± 9 vs 50.9 ± 10.5; P = .42) than the nonaugmented type. In adjusted models, the augmented type was associated with 4.68 (95% CI, 1.27 to 8.09) higher PF (P < .01) and 3.76 (95% CI, -7.85 to 0.33) lower PI (P = .07) compared with the nonaugmented type. Higher body mass index was associated with significantly worse PROMIS PF and PI in both unadjusted (P< .01 and P < .01) and adjusted analysis (P < .01 and P < .01). Varus deformity was associated with significantly lower PF compared with those with isolated ligamentous instability (-4.23 [95% CI, -8.42 to -0.04). No significant differences were observed in PF or PI at follow-up beyond 2 years (P = .55 and P = .37, respectively).

CONCLUSION

Our study showed that the augmented Broström procedure was associated with significantly improved PROMIS scores compared with the nonaugmented Broström procedure to a degree that reaches the minimal clinically important difference for PROMIS. The augmented Broström procedure, therefore, may serve as an effective surgical option to maximize functional outcomes for patients suffering from chronic lateral ankle instability.