Assessment of the Anterior Talofibular Ligament Thickness in Patients with Chronic Stroke: An Ultrasonographic Study

BACKGROUND: Patients with equinovarus deformity have an increased risk of fall and ankle ligament injury, because of inappropriate prepositioning of the ankle at the end of the swing phase, and inadequate leg and ankle stability during the stance phase. Accordingly, the aim of this study is to compare anterior talofibular ligament (ATFL) thickness of chronic stroke patients with that of healthy individuals using ultrasonography. METHODS: This was a case-control study conducted in a university hospital between July 2015 and July 2016. We included 38 patients [study group; mean age, 59.0 ± 11.1 years; mean body mass index (BMI), 25.4 ±4.3 kg/m(2)] and a control group of age-, sex-, and BMI-matched healthy individuals. Demographic and clinical characteristics of the patients (i.e., age, weight, height, Brunnstrom motor recovery stage, Functional Ambulation Scale, Ashworth Scale, and duration of hemiplegia) were recorded during their visits. Furthermore, ultrasound image of the ATFL was obtained from each ankle. The thickness of the ATFL was measured at the midpoint of the ligament between the attachments on the lateral malleolus and the talus using ultrasonography. RESULTS: In the study group, the mean thickness of the ATFLs of the affected side (2.75 ± 0.41 mm) was thicker than both the unaffected side (2.42 ± 0.30 mm) and the healthy controls (2.35 ± 0.19 mm; p = 0.007, p < 0.001, respectively). No differences were seen between the two sides of the control group. CONCLUSION: Chronic stroke patients have a thicker ATFL on both the affected and unaffected sides, compared with healthy individuals. This architectural feature of the ATFL may be a result of equinovarus deformity together with spastic muscles. For this reason, early treatment of deformed ligaments and spastic muscles is needed to prevent equinovarus deformity in patients with stroke.