Balance and walking in facioscapulohumeral muscular dystrophy. Multiperspective assessment

Background: In the Facioscapulohumeral muscular dystrophy (FSHD), the association of ankle muscle impairment with knee, hip and abdominal weakness causes complex alterations of static (postural) and dynamic (walking) balance, increasing the risk of recurrent falls. Stereophotogrammetric system and body-worn gyroscopes were used to focus on locomotor capacity and upper body movements in FSHD patients respectively. No data have been reported about static balance (plantar pressure and stabilometric parameters) and dynamic balance (spatio-temporal parameters during walking) in patients with FSHD. Moreover it is not known if the balance involvement influences disability and quality of life (QoL) of these patients. Aim: The aim of this study is to quantitatively assess static and dynamic balance in FSHD patients and their influence on disability and QoL. Design: Case control-study. Setting: Outpatient Rehabilitation Department. Population: Sixteen FSHD patients were compared with 16 matched healthy subjects. Methods: A baropodometric platform was used to measure plantar pressure and centre of pressure in stance (static evaluation), and spatio-temporal parameters during walking (dynamic evaluation). These quantitative results in FSHD patients were also correlated with validated clinical (Clinical Severity Scale), performance (10m and 2 min Walking Test), disability (Berg Balance Scale, Rivermead Mobility Index) and quality of life (QoL) measures (SF-36, NASS). Results: The patients moved the plantar pressure forward from hindfoot to forefoot. Static balance was significantly reduced in patients compared with healthy subjects. Dynamic evaluation of walking showed a significant reduction of velocity and step length in the patients, and a significant increase in step width. Dynamic and static parameters were significantly related to a reduction of 10 mWT performance while only dynamic parameters were strongly related to disability and QoL. Conclusion: FSHD patients present an abnormal static and dynamic balance and they show compensation strategies to avoid falling . The involvement of the dynamic balance worsens the physical aspects of QoL and induces disability. The involvement of static balance induces a reduction of the performance in brief distances. Clinical rehabilitation impact: The balance training should be considered in the rehabilitation program of FSHD patients; the compensation strategies adopted by these patients should be considered in the ankle foot orthosis treatment. The static and dynamic balance assessment in FSHD patients can be used in natural history studies.