We studied the variations in the ventral rami of 152 brachial plexuses in 77 Korean adults. Brachial plexus were composed mostly of the fifth, sixth, seventh and eighth cervical nerves and the first thoracic nerve (77.0%). In 21.7% of the cases examined, the fourth, fifth, sixth, seventh and eighth cervical and the first thoracic nerves contributed to the plexus. A plexus composed of the fourth, fifth, sixth, seventh and eighth cervical and the first and second thoracic nerves, and a plexus composed of the fifth, sixth, seventh eighth cervical nerves were also observed. The plexuses were classified into three groups according to cephalic limitation, and the plexus of group 2 in which the whole fifth cervical nerve enters the plexus, were observed the most frequent. The average diameter of the sixth and the seventh cervical ventral rami of the plexus was greatest and that of the fifth cervical was smallest. The largest nerve entering the plexus was the sixth or the seventh cervical nerve in about 79% of cases. The dorsal scapular nerve originated from the fifth cervical ventral ramus in 110 cases (75.8%). The long thoracic nerve was formed by joining of roots from the fifth, sixth, and seventh cervical nerves in 76.0% of cases. Also, a branch to the phrenic nerve, the suprascapular nerve, a nerve to the pectoralis major muscle and a nerve to the subscapular muscle arising from the ventral rami of the plexus were observed.
Brachial Plexus/*anatomy & histology ; Cervical Plexus/anatomy & histology ; Female ; Humans ; Male ; Thoracic Nerves/*anatomy & histology

Brachial Plexus ; anatomy & histology ; Brachial Plexus Neuropathies ; therapy ; Humans ; Orthopedics ; education ; Teaching

The presence of anatomical variations of the peripheral nervous system often accounts for unexpected clinical signs and symptoms. We report unusual variations of the lateral and posterior cords of the brachial plexus in a female cadaver. Such variations are attributed to a faulty union of divisions of the brachial plexus during the embryonic period. The median nerve lay medial to the axillary artery (AA) on both sides. On the right, the lateral root of the median nerve crossing the AA and the median nerve in relation to the medial side of the AA was likely the result of a faulty development of the seventh intersegmental artery. We discuss these variations and compare them with the findings of other researchers. Knowledge of such rare variations is clinically important, aiding radiologists, anaesthesiologists and surgeons to avoid inadvertent damage to nerves and the AA during blocks and surgical interventions.
Axillary Artery ; innervation ; Brachial Plexus ; abnormalities ; anatomy & histology ; Cadaver ; Female ; Human Body ; Humans ; Median Nerve ; abnormalities ; anatomy & histology ; Middle Aged

BACKGROUNDThere are few effective methods for treating injuries to the lower trunk of brachial plexus, and the curative effect is usually poor. The purpose of this study was to provide anatomic references for transferring the brachialis muscle branch of musculocutaneous nerve (BMBMCN) for selective neurotization of finger flexion in brachial plexus lower trunk injury, and to evaluate its clinical curative effects.

METHODSMicroanatomy and measurement were done on 50 limbs from 25 adult human cadavers to observe the origin, branch, type of the BMBMCN and median nerve, as well as their adjacent structures. Internal topographic features of the fascicular groups of the median nerve at the level of the BMBMCN were observed. In addition, the technique of BMBMCN transfer for selective neurotization of finger flexion of the median nerve was designed and tested in 6 fresh adult human cadavers. Acetylcholinesterase (AchE) staining of the BMBMCN and median nerve was done to observe the features of the nerve fibers. This technique was clinically tried to restore digital flexion in 6 cases of adult brachial plexus lower trunk injury. These cases were followed up for 3, 6, 9 and 12 months postoperatively. Recovery of function, grip strength, nerve electrophysiology and muscle power of the affected limbs were observed and measured.

RESULTSThe brachialis muscle was totally innervated by the musculocutaneous nerve (MCN). Based on the Hunter's line, the level of the origin of the BMBMCN was (13.18 +/- 2.77) cm. AchE histochemical staining indicated that the BMBMCN were totally made up of medullated nerve fibers. At the level of the BMBMCN, the median nerve consistently collected into three fascicular groups as shown by microanatomy in combination with AchE stain. The posterior fascicular group was mainly composed of anterior interosseous nerves and branches to the palmaris longus. The technique was tested in six fresh cadavers successfully, except that stoma split occurred in one case. Five of the six cases recovered digital flexion 12 months after operation, and at the same time grip strength, muscle power, and nerve electrophysiology also recovered markedly.

CONCLUSIONSThe technique of transferring the BMBMCN for selective neurotization of finger flexion is anatomically safe and effective, with satisfactory clinical outcomes.

Acetylcholinesterase ; analysis ; Adult ; Brachial Plexus ; anatomy & histology ; injuries ; Brachial Plexus Neuropathies ; surgery ; Clinical Trials as Topic ; Female ; Humans ; Male ; Middle Aged ; Musculocutaneous Nerve ; transplantation ; Nerve Transfer ; methods ; Retrospective Studies

This study was designed to investigate the incidence of lateral root of the ulnar nerve through cadaveric dissection and to analyze its impact on myotomes corresponding to the flexor carpi ulnaris (FCU) assessed by electrodiagnostic study. Dissection of the brachial plexus (BP) was performed in 38 arms from 19 cadavers, and the connecting branches between the lateral cord and medial cord (or between lateral cord and ulnar nerve) were investigated. We also reviewed electrodiagnostic reports from January 2006 to May 2008 and selected 106 cases of single-level radiculopathy at C6, C7, and C8. The proportion of abnormal needle electromyographic findings in the FCU was analyzed in these patients. In the cadaver study, branches from the lateral cord to the ulnar nerve or to the medial cord were observed in 5 (13.1%) of 38 arms. The incidences of abnormal electromyographic findings in the FCU were 46.2% (36/78) in C7 radiculopathy, 76.5% (13/17) in C8 radiculopathy and 0% (0/11) in C6 radiculopathy. In conclusion, the lateral root of the ulnar nerve is not an uncommon anatomical variation of the BP and the FCU commonly has the C7 myotome. Needle EMG of the FCU may provide more information for the electrodiagnosis of cervical radiculopathy and brachial plexopathy.
Brachial Plexus/anatomy & histology/physiology ; Brachial Plexus Neuropathies/diagnosis ; Cadaver ; Electrodiagnosis/methods ; Electrophysiology/*methods ; Female ; Forearm/*anatomy & histology ; Humans ; Male ; Muscle, Skeletal/*innervation/physiology ; Radiculopathy/diagnosis ; Ulnar Nerve/*anatomy & histology/physiology

Adult-onset brachial plexopathy can be classified into traumatic and non-traumatic aetiologies. Traumatic brachial plexopathies can affect the pre- or postganglionic segments of the plexus. Non-traumatic brachial plexopathies may be due to neoplasia, radiotherapy, thoracic outlet syndrome and idiopathic neuralgic amyotrophy. Conventional magnetic resonance imaging (MRI) is useful to localise the area of injury or disease, and identify the likely cause. This review discusses some of the common causes of adult-onset brachial plexopathy and their imaging features on MRI. We also present a series of cases to illustrate some of these causes and their MRI findings.
Adult ; Aged ; Brachial Plexus ; anatomy & histology ; diagnostic imaging ; Brachial Plexus Neuropathies ; diagnostic imaging ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Thoracic Outlet Syndrome ; diagnostic imaging ; therapy ; Wounds and Injuries ; diagnostic imaging

BACKGROUND: The ability to explore the anatomy has improved our appreciation of the brachial anatomy and the quality of regional anesthesia. Using real-time ultrasonography, we investigated the cross-sectional anatomy of the brachial plexus and of vessels at the axillary fossa in Koreans. METHODS: One hundred and thirty-one patients scheduled to undergo surgery in the region below the elbow were enrolled after giving their informed written consent. Using the 5-12 MHz linear probe of an ultrasound system, we examined cross-sectional images of the brachial plexus in the supine position with the arm abducted by 90degrees, the shoulder externally rotated, and the forearm flexed by 90degrees at the axillary fossa. The results of the nerve positions were expressed on a 12-section pie chart and the numbers of arteries and veins were reported. RESULTS: Applying gentle pressure to prevent vein collapse, the positions of the nerves changed easily and showed a clockwise order around the axillary artery (AA). The most frequent positions were observed in the 10-11 section (79.2%) for the median, 1-2 section (79.3%) for the ulnar, 3-5 section (78.4%) for the radial, and 8-9 section (86.9%) for the musculocutaneous nerve. We also noted anatomical variations consisting of double arteries (9.2%) and multiple axillary veins (87%). CONCLUSIONS: Using real-time ultrasonography, we found that the anatomical pattern of the major nerves in Koreans was about 80% of the frequent position of individual nerves, 90.8% of the single AA, and 87% of multiple veins around the AA.
Anatomy, Cross-Sectional ; Anesthesia, Conduction ; Arm ; Arteries ; Axilla ; Axillary Artery ; Axillary Vein ; Brachial Plexus* ; Elbow ; Forearm ; Humans ; Musculocutaneous Nerve ; Shoulder ; Supine Position ; Ultrasonography* ; Veins