Neurophysiological aspects of diagnosis of the pudendal nerve and sacral pathways: a summary literature review

The aim of this work was to assess the main methods for diagnosing lesions of the pudendal nerve and sacral pathways, which include it. A critical analysis of the literature data was carried out with a generalization of the currently available results of original studies on identifying the causes of neurological disorders in diseases of the pelvic organs. Key scientific publications of different years, containing materials on this topic, placed in the PubMed, ResearchGate, eLibrary and other available sources were analyzed. The pudendal nerve is the caudal branch of the sacral plexus and facilitates the processes of urination and defecation, as well as perineal skin sensitivity and sexual function. The complex course of the pudendal nerve and the proximity to many dense anatomical structures contribute to the appearance of conditions for its external compression. Most often, the nerve can be compressed in three places (traps): in the space under the tense piriformis muscle, between the sacrospinous and sacroiliac ligaments, and in the genital canal (Alcock’s canal), formed by the splitting of the fascia of the internal obturator muscle. This article discusses advantages and disadvantages of the main diagnostic techniques used to diagnose damage to the pudendal nerve and the pathways, of which it is a part: bulbocavernous reflex, needle electromyography of the pelvic floor muscles with analysis of motor unit potentials, somatosensory and cutaneous sympathetic evoked potentials, transcranial and translumbar magnetic stimulation. Main attention is paid to the method of electrophysiological study of the bulbocavernosus reflex as the most popular and accessible in clinical practice. But despite the advantages of the described methods, currently there is no one that would allow to accurately determine the level of damage to the structures under study, which is often a very important aspect in the choice of tactics for the management and treatment of patients with neurological disorders of the pelvic organs.