Evaluation of balance and improvement of proprioception by repetitive muscle vibration in a 15‐year‐old girl with joint hypermobility syndrome

Abstract

Joint hypermobility syndrome (JHS), alternatively termed hypermobility syndrome or benign joint hypermobility syndrome, is a relatively common rheumatologic condition most frequently diagnosed in women showing chronic pain and other musculoskeletal complaints. There is a significant clinical overlap with Ehlers-Danlos syndrome (EDS), which comprises a clinically variable and genetically heterogeneous group of inherited connective tissue disorders, mainly featuring joint hypermobility, skin hyperextensibility and tissue fragility (1). The revised classification identifies 6 major and other rarer forms (2). Among them, the most common is the hypermobility type (EDS-HT), which is dominated by joint laxity and lacks most cutaneous features observed in other variants (3). Recently, an international group of experts proposed that JHS and EDS-HT are the same condition (4), consisting in a wide clinical spectrum ranging from severe phenotypes with early manifestations to milder forms which are diagnosed in adulthood or, at worst, remain undiagnosed. Proprioception refers to the sense of static position and movement of the limbs and body without using vision. It usually comprises the sense of stationary position of the limbs (limb-position sense) and the sense of limb movement (kinesthesia). These sensations are important for controlling limb movements, manipulating objects that differ in shape and mass, and maintaining an upright posture (5). Lack of proprioception seems a prominent feature in JHS (6,7). Although its relationship with the underlying joint hypermobility is still largely obscure, a handful of studies suggest that improvement of proprioception may be effective for ameliorating both the functional status, including balance, and chronic pain (8). However, as JHS is a systemic, progressive and chronic condition, physical therapy very probably suffers of major limitations, such as time consumption and short-lasting effects. Recently, repetitive muscle vibration (rMV) has been outlined as a non-invasive method that can significantly and persistently improve muscle performance by acting as an important proprioceptive input (9). Although accumulated data are preliminary, this technique is promising for treating postural dysfunction correlated with chronic rheumatologic conditions, such as JHS or EDS-HT.