The brachial plexus is a complex network of nerves and their numerous branches,
responsible for transmitting signals from the spine to the shoulders, arms and
hands. It consists of anterior and posterior branches C5, C6, C7, C8 and T1.
Each primary trunk divides into two branches, an anterior and a posterior, to form
a complex grouping of several divisions.
Anatomopathological types of injury can cause various lesions to the brachial
plexus, and, depending on the nature of the causative agent, can result in open
(knife, firearm or surgical) or closed (usually caused by accidents with traction
forces) wounds, leading to total paralysis of the entire musculature and anaesthesia
of the upper extremity, or partial paralysis divided into superior, middle or inferior.
Secondary trunk injuries can be antero-external, antero-internal and posterior,
producing different types of paralysis. Obstetrical brachial plexus lesions often
occur during childbirth as a result of traction movements that can produce tears,
but these usually heal without the need for treatment or with postural orthotic
Given the complexity of the brachial plexus and its different planes, branches
and grouping into different divisions, symptoms can range from total paralysis
of the upper limb and its anaesthesia to different types of selective paralysis
affecting areas such as the outside of the shoulder, deltoid, supraspinatus,
infraspinatus, biceps brachii, brachialis and brachioradialis, and paralysis of the
flexor muscles of the hand and fingers, complete paralysis of the ulnar nerve
and partial paralysis of the median nerve or paralysis associated with the axillary
and radial nerves. While motor, sensory, electromyographic and radiological
clinical signs are those that determine the degree of lesion, sensory nerve
conduction studies are also of great importance.
As well as the surgical treatment and rehabilitation techniques indicated for each
case, depending on the degree of lesion and its effect on the extremity, whether
it is more or less partial or complete, treatment with orthotic devices is also
suitable provided that it is adapted to each particular case.
The functions of orthoses for the treatment of brachial plexus injuries include
support, positioning of the limb at the right angle due its weight and preventing
subluxation of the gleno-humeral joint. In some cases, unloading requires an
adjustable positioning system that allows the angle of abduction and forward
flexion of the shoulder to be graduated and varied, as well as the flexion of the
elbow and the functional positioning of the hand, thereby enabling the orthosis
to be individually adapted to the needs of each patient.