Entrapment neuropathies and polyneuropathies in joint hypermobility syndrome/Ehlers-Danlos syndrome

Abstract

Objective: This study aims to investigate the involvement of the peripheral nervous system in Ehlers-Danlos syndromes/hypermobility type patients with particular attention to entrapment syndromes.

Methods: We consecutively enrolled Ehlers-Danlos syndromes/hypermobility type patients. Patients underwent clinical, neurophysiological and ultrasound evaluations. Dynamic ultrasound evaluation was also performed in healthy subjects as control group.

Results: Fifteen Ehlers-Danlos syndromes/hypermobility type patients and fifteen healthy subjects were enrolled. Most of patients presented tingling, numbness, cramps in their hands or feet. Clinical evaluation was normal in all patients. One patient was affected with carpal tunnel syndrome and one with ulnar nerve entrapment at elbow. One patient had an increased and hypoechoic ulnar nerve at elbow at ultrasound evaluation. Dynamic ultrasound evaluation of ulnar nerve at elbow showed, in patients, twelve subluxations and three luxations. In the control group dynamic evaluation showed one case of ulnar nerve luxation.

Conclusion: Statistical analysis showed a significant difference in the occurrence of ulnar nerve subluxation and luxation between patients and control subjects.

Significance: The study shows an inconsistency between symptoms and neurophysiological and ultrasound evidences of focal or diffuse nerve involvement. The high prevalence of ulnar nerve subluxation/luxation at elbow in Ehlers-Danlos syndromes/hypermobility type patients could be explained by the presence of Osborne ligament laxity.

Keywords: 1M; 1R; 3M; 5U; BCTQ; Boston Carpal Tunnel Questionnaire; CMAP; CSA; CTS; DML; EDS hypermobility type; EDS-HT; EDSs; Ehlers–Danlos syndrome; Ehlers–Danlos syndromes; Entrapment neuropathy; FUNCT; HCTDs; JHM; JHS; Joint hypermobility syndrome; MNCV; SAP; SNCV; SYMPT; UNE; US; Ultrasound; carpal tunnel syndrome; compound motor action potential; cross sectional area; distal motor latency; fifth digit to wrist for ulnar nerve; first digit to wrist for median nerve; first digit to wrist for radial nerve; functional status of CTS; heritable connective tissue disorders; joint hypermobility; joint hypermobility syndrome; motor nerve conduction velocity; sensory action potential; sensory nerve conduction velocity; symptoms of CTS; third digit to wrist for median nerve; ulnar nerve entrapment at elbow; ultrasonographic.