Brachial plexus injury (BPI) These nerves originate in the fifth, sixth, seventh and eighth cervical (C5–C8), and first thoracic (T1) spinal nerves, and innervate the muscles and skin of the chest, shoulder, arm and hand.

Injury classified Obstetric Mechanical injury involving shoulder dystocia during difficult childbirth Falls from a height on to the side of the head and shoulder, the nerves of the plexus are violently stretched Direct violence or gunshot wounds, by violent traction on the arm, or by efforts at reducing a dislocation of the shoulder joint

Signs and symptoms : A limp or paralyzed arm, lack of muscle control in the arm, hand, or wrist, and lack of feeling or sensation in the arm or hand. Nerve compression or stretch. Infants, in particular during delivery and these present with typical patterns of weakness depending on which portion of the brachial plexus The most severe form of injury is nerve root avulsion complete weakness in corresponding muscles.

Location of the nerve damage * Musculocutaneous nerve damage weakens elbow flexors, * Median nerve damage causes proximal forearm pain * Ulnar nerve causes weak grip and finger numbness * Total and irreversible paralysis * The cardinal signs of brachial plexus injury then, are weakness in the arm, diminished reflexes, and corresponding sensory deficits.

Classification : * Neurapraxia * Axonotmesis * Neurotmesis The severity of brachial plexus injury is determined by the type of nerve damage. Seddon's classification, based on three main types of nerve fiber injury : * Neurapraxia * Axonotmesis * Neurotmesis

Injury type : Erb's palsy ( upper trunk BPI , C5-6) Mixd palsy Klumpke's paralysis ( lower trunk BPI C8-T1)

DiagnosIs : Clinical exams Axon reflex testing Electrophysiological testing Myelographic study MRI

* Some injuries may heal without treatment * Many infants improve or recover within 6 months * The ability to bend the elbow (biceps function) by the third month of life is considered an indicator of probable recovery * Additional upward movement of the wrist, as well as straightening of thumb and fingers an stronger indicator of excellent spontaneous improvement

Treatment : Orthosis/splinting Occupational or physical therapy Surgery

Surgery : Hand Wrist Forearm Elbow Upper arm Shoulder

Opponoplasty of hand Pinch function

Wrist arthrodesis

Steindler-Mayer elbow flexorplasty

Steindler-Mayer elbow flexorplasty

Shoulder Tendon Transfer & Elbow Flexorplasty

Steindler-Mayer elbow flexorplasty

Shoulder Tendon Transfer & Elbow Flexorplasty

Elbow Flexorplasty & Shoulder Arhtrodesis

Shoulder Tendon Transfer & Elbow Flexorplasty

Prognosis : Avulsion and rupture injuries require timely surgical intervention for any chance of recovery. The potential for improvement varies, but there is a fair prognosis for spontaneous recovery with a return of function. Reconstruction of paralytic arm is remedy procedure.

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Further References : Brachial Plexus Injuries: National Institute of Neurological Disorders and Stroke. Last updated September 29, 2008 - see bottom of webpage. Retrieved 2009-10-11. "Brachial Plexus Injury”: Description & illustrations". Cincinnati Children's Hospital, health information website Retrieved 2013-10-11.

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