Muscle mass, muscle strength, functional performance, and physical impairment in women with the hypermobility type of Ehlers‐Danlos syndrome

Abstract

Objective. To investigate lower extremity muscle mass, muscle strength, functional performance, and physical impairment in women with the Ehlers-Danlos syndrome hypermobility type (EDS-HT). Methods. Forty-three women with EDS-HT and 43 sex-and age-matched healthy control subjects participated. Muscle mass was determined by dual x-ray absorptiometry. Muscle strength and muscle strength endurance were measured with isokinetic dynamometry at angular velocities of 60, 180, and 240°/second. Static muscle endurance during posture maintenance was also assessed. Pain and fatigue were simultaneously evaluated by visual analog scale and the Borg scale, respectively. In addition, the chair rise test for assessment of functional performance and the Arthritis Impact Measurement Scales (AIMS) for physical impairment evaluation were used. Results. Compared to control subjects, EDS-HT patients showed substantial lower extremity muscle weakness, reflected by significantly reduced knee extensor and flexor muscle strength and endurance parameters, with differences ranging from ؊30% to ؊49%; reduced static muscle endurance time; and diminished functional performance. Lower extremity muscle mass was similar in both groups and unlikely to affect the muscle strength results. By contrast, pain and fatigue were omnipresent and increased remarkably due to the tests. Furthermore, the EDS-HT group was physically impaired, especially in the AIMS domain walking and bending. Conclusion. This study demonstrates severely reduced quantitative muscle function and impairment in physical function in patients with EDS-HT compared to age-and sex-matched controls. The muscle weakness may be due to muscle dysfunction rather than reduced muscle mass. Whether muscle strength and endurance can be improved by appropriate exercise programs needs evaluation in further studies.

The association between muscle strength and activity limitations in patients with the hypermobility type of Ehlers–Danlos syndrome: the impact of proprioception

“…Although a reduced sensor density has not been demonstrated in EDS-HT, the presence of muscle atrophy has indeed been shown in EDS-HT patients. [20] Therefore, the prevention of muscle atrophy by muscle training could also protect against poor proprioception. If connective tissue laxity and muscle atrophy are responsible for poor proprioception, for reasons of parsimony, this should be studied in longitudinal studies first before implementing in clinical practice.…”

“…dancers) and symptomatic forms of GJH (e.g. EDS-HT, hypermobility syndrome) [19][20][21] In these studies, muscle weakness was found to be associated with pain [22] and fatigue. [21] However, whether these factors moderate the association between muscle strength and activity limitations is unknown.…”

Ehlers-Danlos Syndrome, Hypermobility Type: Impact of Somatosensory Orthoses on Postural Control (A Pilot Study)

“…Hence, it is likely that hEDS induces not only a proprioceptive deficit but, more broadly, a somatosensory deficit. Consequently, the major functional disabilities expressed by these patients, including clumsiness and falls, which sometimes lead to kinesiophobia, could be the result of this somatosensory impairment (Rombaut et al, 2012). …”

The Ehlers-Danlos Syndrome

“…Our studies showed that EDS-HT patients have reduced knee joint proprioception [ 16 ], as well as a severely reduced quantitative muscle function and impaired in physical functioning, compared to age and sex-matched controls. EDS-HT patients present lower extremity muscle weakness, which appears not to be caused by reduced muscle mass but rather by intrinsic muscular dysfunction, associated with muscle pain and fatigue [ 17 ].…”