The ulnar dorsal aspect of the hand is predominantly innervated by the dorsal ulnar cutaneous nerve with variable input from the superficial radial cutaneous nerve. This cross innervation can cause difficulty in interpreting low amplitude sensory nerve action potential for the dorsal ulnar cutaneous nerve particularly when facing suspected ulnar neuropathyat the elbow. In three subjects with lo...

OBJECTIVE To evaluate each digital branch of the median sensory nerve and motor nerves to abductor pollicis brevis (APB) and 2nd lumbrical (2L) according to the severity of carpal tunnel syndrome (CTS). METHODS A prospective study was performed in 67 hands of 41 patients with CTS consisting of mild, 23; moderate, 27; and severe cases, 17. Compound muscle action potentials (CMAPs) were obtaine...

BACKGROUND AND PURPOSE Stroke-induced hemiparesis involving the arm and hand results in regular, repeated overuse of the opposite hand and wrist. Because repetitive hand and wrist movement is a common cause of carpal tunnel syndrome (CTS), we examined the nonparetic upper limb in stroke patients for evidence of CTS. METHODS We measured bilaterally sensory nerve conduction velocity (SNCV), mot...

Two patients with signs and symptoms of paralysis of the brachial plexus, caused by compression during surgery in one (case 1) and by a knapsack in the other (case 2), were examined. The characteristic electrophysiological findings were: (i) severe attenuation of amplitude of motor and sensory nerve action potentials evoked or recorded above the site of nerve injury compared to those evoked or ...

Guillain-Barré syndrome (GBS) is an immune-mediated polyradiculoneuropathy with acute onset and rapid clinical worsening; early diagnosis and immunomodulating therapy can ameliorate the course of disease. During the first days, however, nerve conduction studies (NCSs) are not always conclusive. Here, we describe a 73-year-old man presenting with progressive muscular weakness of the lower limbs,...

Complex nerve models have been developed for describing the generation of action potentials in humans. Such nerve models have primarily been used to model implantable electrical stimulation systems, where the stimulation electrodes are close to the nerve (near-field). To address if these nerve models can also be used to model transcutaneous electrical stimulation (TES) (far-field), we have deve...

background: the use of organophosphates (ops) in developing countries is rising in large quantities and non-secure methods. this problem not only causes acute poisoning but also may lead to chronic diseases such as polyneuropathy. in iran, 60% of pesticides are organophosphate compounds that may lead to delayed polyneuropathy. objectives: the purpose of the current study was to evaluate delayed...

Two siblings are described with mutilating lesions of the feet and hands, with sensory disturbances and muscle amyotrophy. The motor and afferent nerve conduction velocities were at the lower limit of normal. The nerve action potentials disappeared, first with percutaneous stimulation of the fingers and later with more proximal direct nerve stimulation. Early in the course of the illness indole...

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% 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 origin of the action potential in the cochlea has been a long-standing puzzle. Because voltage-dependent Na+ (Nav) channels are essential for action potential generation, we investigated the detailed distribution of Nav1.6 and Nav1.2 in the cochlear ganglion, cochlear nerve, and organ of Corti, including the type I and type II ganglion cells. In most type I ganglion cells, Nav1.6 was presen...