Ulnar nerve lesions associated with the carpal tunnel syndrome

Abstract

SUMMARY Electrophysiological studies were performed on median and ulnar nerves in 234 cases of carpal tunnel syndrome. Abnormalities of the ulnar nerve sensory action potential were found in 39.3%0 of cases. The amplitude of the ulnar nerve sensory action potential was related to the amplitude of the median nerve sensory action potential, and to the median nerve motor conduction velocity in the forearm. The findings suggest that in a significant proportion of patients with carpal tunnel syndrome, a more generalized subclinical neuropathy may be present.The association of ulnar nerve abnormalities with carpal tunnel syndrome has received little attention. In performing routine diagnostic nerve conduction studies in patients with the syndrome, an appreciable incidence of such abnormalities was noted. This stimulated a review of all patients with carpal tunnel syndrome studied over the past five years with particular emphasis on the frequency of ulnar nerve abnormalities and their significance in the pathogenesis of the syndrome. METHODS SUBJECTS There were 234 cases of carpal tunnel syndrome in the series. These comprised 214 patients, 20 of whom had bilateral abnormalities; 119 of the patients were women and 95 were men. Their ages ranged from 19 to 87 (mean, 54) years. Thirty-four control subjects were also studied in whom there was no history or physical sign of neurological disease nor of systemic disorders known to predispose to neuropathy. Their ages ranged from 18 to 77 (mean, 47) years.The criteria used for the diagnosis of carpal tunnel syndrome were a history or physical signs of carpal tunnel syndrome together with one or more of the following three electrophysiological abnormalities (Gilliatt and Sears, 1958): (1) a median motor latency at the wrist greater than 5 0 msec; (2) a median sensory latency at the wrist greater than

The Impact of Carpal Tunnel Syndrome on Ulnar Nerve: An Electro-Clinical Study

“…Similar results were found by some authors [10,28,29]. However, there was no significant positive correlation between MDLu and MDLm, which was also noted by Ginanneschi et al [28].…”

“…Similar results were found by other authors both for sensory parameters of the ulnar nerve [3,10,27] and MDLu [10,28]. However, Azmy et al [30] found a non-significant difference between APSu averages of healthy and affected hands.…”

“…However, there was no significant positive correlation between MDLu and MDLm, which was also noted by Ginanneschi et al [28]. Moreover, contrary to what has been reported in other studies [3,10,27,28], we did not detect correlations, neither positive nor negative, between other parameters, especially SCVu and SVCm [28], ASPu and SCVm [10], ASPu and MDLm [3,10,28], SCVu and MDLm [27,28] and sensory distal latency of ulnar nerve (SDLu) and MDLm [27].…”

“…Most authors who conducted similar studies compared the parameters of the ulnar nerve in affected hands with reference standards used in daily practice [7,9,10,34,35]. This could be a methodological error since there is a great variability of these parameters in normal subjects, especially according to the height and the recording conditions such as skin temperature.…”

“…This concerned especially mean age which was equal to 45 years [5,10], women predominance (93% of patients) [19][20][21], frequent obesity (49% had a BMI value beyond 30 kg.m −2 ) [21][22][23][24] and predominance of bilateral CTS (86% of patients) [25,26].…”