Morphological Prerequisites of Originupper, Middle, and Lower Syndromes of Injury of the Primary Bundles of the Brachial Plexus

Plexopathies of various origins are a dangerous complication that often leads to severe functional disorders. When the branches of the brachial plexus are aff ected, the upper, middle, and lower syndromes of damage to the primary bundles are observed. The syndrome of the upper primary bundle occurs when the front branches of the V-VI cervical nerves or part of the brachial plexus, where the corresponding nerves connect, are aff ected. In upper bundle syndrome, a simultaneous lesion of the axillary nerve, long thoracic nerve, medial and lateral thoracic nerves, subscapular nerve, dorsal scapular nerve, musculocutaneous nerve, and part of the radial nerve is noted. When the front branch of the VII cervical nerve is damaged, a syndrome of damage to the middle primary bundle of the brachial plexus occurs, in which there is a loss or di ffi culty in extending the shoulder, hand, and fi ngers. There is also incomplete paralysis of the triceps brachii, extensor pollicis, and abductor pollicis longus. The syndrome of the lower primary bundle of the brachial plexus occurs when the VII cervical and I thoracic nerves or the lower primary bundle of the plexus formed from them are damaged. When all the roots of the brachial plexus (CV-ThI) are damaged, a total type of lesion develops. A mixed type of paralysis, characterized by isolated damage to the ulnar, axillary, radial, or median nerve, or a combination thereof, may also be observed Successful treatment of patients with brachial plexus injury begins with a thorough understanding of the anatomy of the primary brachial plexus bundles and the pathophysiology of nerve damage. The severity of the damage depends on the nature of the injury and the topography of the nerve bundles. The use of modern diagnostic methods and a thorough history are critical to choosing a treatment plan that includes drug therapy, rehabilitation measures, and, if necessary, nerve reconstruction or secondary musculoskeletal surgery.