What is the place of electroneuromyographic studies in the diagnosis and management of pudendal neuralgia related to entrapment syndrome?

Entrapment of the pudendal nerve may be at the origin of chronic perineal pain. This syndrome must be diagnosed because this can result in the indication of surgical decompression of the entrapped nerve for pain relief. Electroneuromyographic (ENMG) investigation is often performed in this context, based on needle electromyography and the study of sacral reflex and pudendal nerve motor latencies. The limits of ENMG investigation, owing to various pathophysiological and technical considerations, should be known. The employed techniques do not assess directly the pathophysiological mechanisms of pain but rather correlate to structural alterations of the pudendal nerve (demyelination or axonal loss). In addition, only direct or reflex motor innervation is investigated, whereas sensory nerve conduction studies should be more sensitive to detect nerve compression. Finally, ENMG cannot differentiate entrapment from other causes of pudendal nerve lesion (stretch induced by surgical procedures, obstetrical damage, chronic constipation...). Thus, perineal ENMG has a limited sensitivity and specificity in the diagnosis of pudendal nerve entrapment syndrome and does not give direct information about pain mechanisms. Pudendal neuralgia related to nerve entrapment is mainly suspected on specific clinical features and perineal ENMG examination provides additional, but no definitive clues, for the diagnosis or the localization of the site of compression. In fact, the main value of ENMG is to assess objectively pudendal motor innervation when a surgical decompression is considered. Perineal ENMG might predict the outcome of surgery but is of no value for intraoperative monitoring.

[Phrenic nerve paralysis of obstetrical origin: favorable course using continuous positive airway pressure]. / Paralysie phrénique isolée obstétricale: évolution favorable sous pression expiratoire positive par voie nasale.

INTRODUCTION: Isolated diaphragmatic paralysis due to obstetrical factors is rare and therapeutic management modalities are not quite clear. CASE REPORT: A neonate born by breech delivery presented with respiratory distress due to isolated paralysis of the right hemidiaphragm. The clinical course was progressive, his condition worsening with oxygen supplementation. Continuous positive airway pressure (CPAP) delivered via a nasal cannula was started in the one-month-old child, inducing gradual improvement towards recovery at the age of two months and a half. CONCLUSION: Non-invasive nasal CPAP should be proposed for the treatment of phrenic nerve obstetrical palsy before introducing more invasive ventilation techniques. Surgical plication should be delayed until the child reaches the age of at least three months.

[Vasomotor disorders of the hand and carpal tunnel syndrome]. / Troubles vasomoteurs des mains et syndrome du canal carpien.

Clinical electrophysiological and chronothermodynamic examinations were performed on 71 patients with paresthesiae and pain of the hands. In 35 patients, the electromyographic examination confirmed the diagnosis of carpal tunnel syndrome on the basis of clear signs of chronic compression of the median nerve at the carpal tunnel. In the other 36 patients, the electro-physiological findings were normal. Twenty-nine patients with bilateral (n = 24) or unilateral (n = 5) carpal tunnel syndrome, and 29 patients without, this syndrome had chronothermodynamic abnormalities demonstrating the vascular origin of the disorders of the hands; in 18 patients, a Raynaud's syndrome was suspected on the basis of severe dysthermia. In 7 patients, the origin of pain and paresthesiae remained unknown. This study shows that (i) vascular disorders of the hand are very frequent in patients with paresthesiae and pain of the hands and may mimic a carpal tunnel syndrome, and (ii) clinical examination is insufficient to assess the diagnosis of carpal tunnel syndrome. Before deciding on any kind of therapy, this diagnosis has to be assessed on electrophysiological and chronothermodynamic examinations performed according to precise protocols.