Frequency of Pes Planus and Posterior Tibial Tendon Dysfunction in Patients With Ankylosing Spondylitis

Posterior tibial tendon dysfunction is the most common cause of acquired pes planus deformity in healthy adults. The posterior tibial tendon stabilizes the hindfoot against valgus and eversion forces and acts as a support along the medial longitudinal arch. If the posterior tibial tendon loses its functionality, the other ligaments of the foot and the joint capsule gradually weaken as the height of the medial longitudinal arch decreases or disappears, and it develops with pes planus. The presence of pes planus and spondyloarthropathy are also risk factors for the development of posterior tibial tendon dysfunction. 100 participants aged between 20-70 years with ankylosing spondylitis were planned to be included in this investigation. Posterior tibial tendon dysfunction frequency of patients with ankylosing spondylitis will be evaluated by both clinical examination and musculoskeletal ultrasonography device. The posterior tibial tendon will be evaluated by ultrasonography in terms of tendon diameter and fluid presence in 2 different locations in the retromalleolar area. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Ankylosing Spondylitis Quality of Life (ASQoL) Scale, Functional reach test, Timed up and go test, Berg Balance Scale, Dynamic and static balance with the Sportkat device will be used as evaluation parameters. It was planned that the evaluations were made once.