We reviewed 101 patients with injuries of the
terminal branches of the infraclavicular brachial plexus sustained between
1997 and 2009. Four patterns of injury were identified: 1) anterior
glenohumeral dislocation (n = 55), in which the axillary and ulnar
nerves were most commonly injured, but the axillary nerve was ruptured
in only two patients (3.6%); 2) axillary nerve injury, with or without
injury to other nerves, in the absence of dislocation of the shoulder
(n = 20): these had a similar pattern of nerve involvement to those
with a known dislocation, but the axillary nerve was ruptured in
14 patients (70%); 3) displaced proximal humeral fracture (n = 15),
in which nerve injury resulted from medial displacement of the humeral
shaft: the fracture was surgically reduced in 13 patients; and 4) hyperextension
of the arm (n = 11): these were characterised by disruption of the
musculocutaneous nerve. There was variable involvement of the median
and radial nerves with the ulnar nerve being least affected. Surgical intervention is not needed in most cases of infraclavicular
injury associated with dislocation of the shoulder. Early exploration
of the nerves should be considered in patients with an axillary
nerve palsy without dislocation of the shoulder and for musculocutaneous
nerve palsy with median and/or radial nerve palsy. Urgent operation
is needed in cases of nerve injury resulting from fracture of the
humeral neck to relieve pressure on nerves.