Brachial Plexus Injuries
The brachial plexus begins at the neck and crosses the upper chest to the armpit
- C4-T1 cervical root has lateral, posterior, and medial cords
- at the lateral border of the pectoralis minor, these cords ultimately form the 5 major peripheral nerves of the arm: **musculocutaneous, axillary, radial, median, and ulnar
Mechanism of Injury
- often occurs when arm is forcibly pulled or stretched, fall onto the shoulder, penetrating compression, or closed traction injuries
- high speed motor vehicle crashes
Presentation
- upper extremity paresthesia and shoulder weakness [neck and shoulder girdle and upper arm] with pain-free ROM of cervical spine. Cervical radiculopathy
- weakness, reflex and sensory deficits
- adduction and internal rotation of the shoulder indicate weakness of the deltoid + infraspinatus muscles [C5]; elbow extension is due to weakness of the biceps [C6], and flexion of the digits and wrists is due to weakness of the extensors [C7]
- Mucocutaneous nerve injury: numbness to the lateral forearm
- paresthesia and/or motor loss in may be transient [ex: neuropraxia] or permanent.
Management
- Depends on the extent of the injury. Orthopedist referral
- Electromyography/nerve conduction velocity [EMG/NCV] can help localize the lesion and aid in prognosis. Can show changes as early as 3 weeks after injury
