Temporal changes in the talofibular distance during ultrasound-guided anterior drawer testing in grade III lateral...

Grade III lateral ankle sprains feature complete anterior talofibular ligament rupture and severe mechanical instability. Although conservative care is standard, the time course of anterior displacement remains unclear.

This single-center retrospective case series included eight consecutive patients (≥ 12 years old) with Grade III lateral ankle sprains confirmed by radiography and ultrasound (April 2021-December 2023). Patients underwent ultrasound-guided reverse anterior drawer testing at four time points: initial consultation and weeks 1, 3, and 5. The primary outcome was change in talofibular distance (max-min during testing). All measurements were obtained by one examiner using automated length measurement system software. Patients were immobilized for up to 2 weeks, then used a functional brace until week 8. Early weight-bearing was allowed. Rehabilitation began after immobilization, with jogging and sport-specific drills at week 3, with return to sport targeted for week 8.

Mean change in talofibular distance (mm) was 2.99 ± 1.06 at baseline, 2.73 ± 1.08 at week 1, 1.02 ± 0.97 at week 3, and 1.32 ± 0.96 at week 5; unaffected side 1.23 ± 0.23. Significant improvement was seen between weeks 1 and 3 (p = 0.007) and relative to baseline at weeks 3 (p < 0.001) and 5 (p = 0.020).

In this small, single-center retrospective series, anterior displacement decreased most prominently by week 3 after injury. These findings are hypothesis-generating and require confirmation in larger prospective studies before informing treatment protocols or return-to-sport decisions.