A new approach to estimation of the number of central synapse(s) included in the H-reflex.

Background: Among the main clinical applications of the H-reflex are the evaluation of the S1 nerve root conductivity such as radiculopathy and measurement of the excitability of the spinal motoneurons in neurological conditions. An attempt has been made to reduce the pathway over which H-reflex can be obtained in a hope to localize a lesion to the S1 nerve root, so the S1 central loop has been suggested. The main goal of this study is the estimation of the H-reflex number of synapse(s) for better understanding of the physiology of this practical reflex.

Effects of age and leg length upon central loop of the gastrocnemius-soleus H-reflex latency.

Background: central loop of the gastrocnemius-soleus H-reflex latency (Tc) that looks promising in the diagnosis of S1 radiculopathy; has been investigated in a few studies and only two of them have focused on the constitutional factors affecting it. Although leg length has been shown to contribute to the Tc, the role of age is controversial. More confusing, none of the previously performed studies have used strict criteria to rule out subclinical neuropathy, so the results could be misleading.

A study of the sympathetic skin response and sensory nerve action potential after median and ulnar nerve repair.

The purpose of this study was to compare SSR with sensory nerve action potential (SNAP) responses in regeneration of injured peripheral nerves after nerve repair. We studied 10 male patients with a mean age of 26.7 years.

The central loop of H-reflex in the S1 spinal nerve: normal values and constitutional influencing factors.

Objective: To investigate the central loop of H reflex in the S1 nerve and the constitutional influencing factors in normal healthy individuals.

Materials And Methods: The study was performed on 39 apparently healthy volunteers. To obtain central H-reflex, the cathode electrode was inserted at a point 1 cm medial to the posterior superior iliac spine, perpendicular to the frontal plane.

Meralgia paresthetica as the presenting feature of chronic appendicitis.

Meralgia paresthetica is an entrapment syndrome of the lateral cutaneous nerve of the thigh manifesting as paresthesia, pain, numbness, or sensory loss in the distribution of the nerve. A variety of causes have been described; however, the etiology often remains unknown. On the basis of our investigations with a patient with meralgia paresthetica, we determined that an inflammatory rather than mechanical effect on the lateral cutaneous nerve of the thigh may account for the pathogenesis; however, a certain conclusion about this issue can not be made.

Fibrillation potentials and positive sharp waves in patients with antecedent paralytic poliomyelitis.

The diagnosis of post-polio syndrome depends not only on clinical signs, but on sophisticated laboratory tests such as histochemical muscle biopsy and immunohistochemical studies which are very expensive and not available in all laboratories. From eighty-eight previous poliomyelitis victims, muscles with grade 4 or lower strength were examined electromyographically for fibrillation potentials and positive sharp waves. There were no muscles with grade III or IV fibrillation potential and positive sharp waves, 8 with grade I (3.

Carpal tunnel syndrome: reappraisal of five clinical tests.

A combination of 5 clinical tests: Tinel (9, 10), Phalen (wrist flexion) (1, 2, 17), reverse Phalen (wrist extension) (4), carpal compression (11, 18), vibration (13, 14) was used in 74 hands with symptoms of carpal tunnel syndrome and proved by median sensory conduction velocity and distal latency across wrist and compared with 58 normal hands. Tinel test was the most specific and the least sensitive, vibration test was the most sensitive and the least specific. Carpal compression test was less sensitive and specific compared to Durkan's study.

Median-radial sensory latencies comparison as a new test in carpal tunnel syndrome.

Median and radial distal sensory latencies (DSL) were compared in 50 patients with carpal tunnel syndrome (CTS) and 50 healthy subjects by stimulating each nerve separately and recording sensory nerve action potential (SNAP) from standard anatomical locations for stimulation and recording sites. The range of difference between median DSL and radial DSL was 0.18 -1.