# Cumberland Ankle Instability Tool (CAIT) demonstrates comparable predictive validity to Foot and Ankle Ability Measure (FAAM) for return to sport after anatomic ankle ligament reconstruction

## TL;DR

The study found that the Cumberland Ankle Instability Tool is as effective as the Foot and Ankle Ability Measure in predicting return to sport after ankle ligament surgery.

## Contribution

This study demonstrates that CAIT is a valid and efficient alternative to FAAM for outcome assessment after anatomic ankle ligament reconstruction.

## Key findings

- CAIT and FAAM scores showed strong correlations preoperatively and at all postoperative time points.
- Both tools significantly discriminated between patients who returned to sport and those who did not at 3, 6, and 12 months.
- AUC analysis found no significant difference in predictive ability for return to sport between CAIT and FAAM.

## Abstract

Anatomic ankle ligament reconstruction (AALR) has shown positive outcomes in managing chronic lateral ankle instability (CLAI). Patient‐reported outcome measures (PROMs) are essential for evaluating treatment efficacy, but the optimal tool for this population remains unclear. This study aimed to compare the discriminative capacity and predictive ability for Return to Sport (RTS) between two validated PROMs: the Foot and Ankle Ability Measure (FAAM) and the Cumberland Ankle Instability Tool (CAIT), in patients undergoing AALR.

A retrospective study included 140 patients who underwent arthroscopically‐assisted AALR with gracilis autograft or allograft between January 2019 and January 2023, with a minimum 12‐month follow‐up. Patients completed FAAM and CAIT questionnaires preoperatively and at 3, 6 and 12 months postoperatively. Correlations between FAAM and CAIT scores were assessed using Spearman coefficients across different timelines. Discriminative capacity and predictive ability for RTS were also compared using Wilcoxon test, ROC and Area under the Curve (AUC) analysis.

Strong correlations between CAIT and FAAM were observed preoperatively (r = 0.53) and postoperatively at 3 months (r = 0.56), 6 months (r = 0.64) and 12 months (r = 0.69). Both scores discriminated significantly between RTS and non‐RTS groups, with higher scores in the RTS group at 3 months (CAIT: 23 vs. 17, p < 0.001; FAAM: 84 vs. 72, p < 0.001), 6 months (CAIT: 27 vs. 19, p < 0.001; FAAM: 90 vs. 74, p < 0.001), and 1 year (CAIT: 29 vs. 24, p < 0.001; FAAM: 93 vs. 84, p < 0.001). AUC analysis revealed no significant difference in predictive ability for RTS between CAIT and FAAM at 3 months (n.s.), 6 months (n.s.) and 12 months (n.s.).

Both CAIT and FAAM demonstrated comparable discriminative capacity and predictive ability for Return to Sport following AALR; given its brevity, ease of administration, and specificity to ankle instability, CAIT is a valid and efficient alternative to FAAM for postoperative outcome assessment in this population.

Level III.