Retrospective evaluation of graded stress examination of the ankle

Stress radiography of the ankle commonly is used to evaluate talar tilt in patients with a history of inversion ankle sprains. Manual and instrumented procedures have been variously described in the literature. No reports have documented normative talar tilt as measured using the Telos ankle stress device in a large clinical population. In addition, little has been done to examine the value of using graded displacement forces compared with a single displacement force. Bilateral Telos examinations from 113 consecutive patients taken during a 4-year period were evaluated for this study. No measurable talar tilt was observed in 65.8% of the ankles in this study. Talar tilt ranged from 1.7 degrees to 24.9 degrees in injured ankles. In patients with quantifiable talar tilt, all had greater talar tilt at the 15 kPa force than at all other forces. Because of the variability in talar tilt in injured and comparison ankles, clinical conclusions regarding injury severity cannot be made on measured talar tilt alone. The analysis suggests that inversion stress examination is helpful in documenting gross talar instability, but the discriminant value of the procedure to determine the anatomy and severity of lateral ligament injury is tenuous.