Stress ultrasonography (US) has been shown to be a valid procedure for evaluating chronic anterior talofibular ligament (ATFL) injury.  The ratio of stress/nonstress ATFL length (ATFL ratio) as measured on US is clinically useful; however, there are no published normative data concerning this ratio.


 To report a normative value of the ATFL ratio on US and evaluate the relationships between sex, generalized joint laxity (GJL), and the grade of anterior drawer test (ADT).


 CONCLUSION
 The normative value of the ATFL ratio on stress US was 1.07 ± 0.04 in men and 1.09 ± 0.04 in women.  These findings will be useful for future studies seeking to establish the cutoff value of the ATFL ratio for diagnosing chronic lateral ankle stability on stress US.
US