Functional neurological signs in hypermobile Ehlers-Danlos syndrome and hypermobile spectrum disorders with suspected neuropathic pain

Abstract

Background: The hypermobile Ehlers-Danlos syndrome (hEDS) and hypermobility spectrum disorders (HSD) are connective tissue disorders characterized by generalized joint hypermobility, associated with chronic pain and several symptoms, such as fatigue, dysautonomia, as well as psychiatric co-morbidities. Clinical observations of unusual manifestations during systematic sensory testing raised the question of a possible co-existence with a functional neurological disorder (FND). Hence, this study aimed to assess the presence of positive functional neurological signs (FNS) in a cohort of patients with hEDS/HSD.

Methods: The clinical data of hEDS/HSD patients (N = 24) were retrospectively analyzed and compared to a prospectively recruited age-/sex-matched healthy control group (N = 22). Four motor- and three sensory-positive FNS were assessed.

Results: Twenty-two patients (92%) presented at least one motor or sensory FNS. Five patients (21%) presented only a single FNS, 14 presented between 2 and 4 FNS (58%), and 3 patients presented 5 or more FNS (12%). None of the healthy controls presented motor FNS, and only two presented a sensory FNS.

Conclusions: The presence of FNS in hEDS/HSD deserves better clinical detection and formal diagnosis of FND to offer more adequate care in co-morbid situations. In fact, FND can severely interfere with rehabilitation efforts in hEDS/HSD, and FND-targeted physical therapy should perhaps be combined with EDS/HSD-specific approaches.

Keywords: chronic pain; functional neurological disorder; functional neurological positive signs; hypermobile Ehlers-Danlos syndrome; hypermobile spectrum disorder.