Decreased Physical Activity Levels Relates To Ligament Thickness After Injury

Abstract

PURPOSE: To examine thickness of the anterior talofibular ligament (ATFL) and if that thickness relates to physical activity levels one year after an ankle sprain. METHODS: Twenty college students (8 males and 12 females, age = 21.2 ± 2.4 yr., mass = 80.9 ± 21.6 kg, ht = 173.3 ± 10.6 cm) with an acute LAS and 20 healthy matched controls (8 males and 12 females, age = 21.9 ± 2.8 yr., mass = 79.1 ± 20.2 kg, ht = 172.5 ± 9.8 cm) participated in the study. ATFL thickness was measured with a LOGIQ Book (GE Healthcare, Waukesha, WI) diagnostic ultrasound. The examiner orientated the probe to view the cross sectional view of the lateral malleolus and the lateral talar articular surface cartilage and the neck of the talus. Measurements of ATFL thickness were made using ImageJ software (National Institutes of Health, Bethesda, MD). Thickness of the ATFL was measured at the midpoint of the ligament between the attachments of the lateral malleolus and talus. The main outcome measures were the thickness of the ATFL (mm) at 3 days post LAS and 1 year post LAS, and physical activity levels as measured by the IPAQ and NASA physical activity scales. RESULTS: There was a significant relationship between ATFL thickness and both the IPAQ and NASA physical activity scales. As ligament thickness increased, “average time spent performing vigorous physical activity” significantly decreased (p = .04, r2 = -.86) and “average time spent performing moderate physical activity” (p = .02, r2 = -.84) one year after injury. Subjects with a LAS also had a significant relationship with time spent walking (p = .01, r2 = -.92), and days per week where they pursued vigorous activity (p = .02, r2 = -.81) or moderate activity (p = .04 r2 = -.85) one year after their sprain. As ligament thickness increased, overall subjective physical activity scores significantly decreased. CONCLUSIONS: One year after a LAS subjects had a significant relationship with ATFL thickness and activity levels. The changes in ATFL morphology may lead to the decreased physical activity levels due to the feeling of the ankle being unstable. Future research needs to focus on early interventions to ensure proper ligament healing occurs to restore joint function after an ankle sprain.