The guidelines developed by the New York State Workers Compensation Board are intended to assist healthcare professionals in providing appropriate treatment for brachial plexus injuries.
Tailored for medical practitioners, these Workers Compensation Board guidelines offer support in determining the right course of action for individuals with brachial plexus injuries.
It’s important to emphasize that these guidelines do not replace clinical judgment or professional experience. The ultimate decision regarding treatment for brachial plexus injuries should be a collaborative one, involving the patient and their healthcare provider in consultation.
Brachial Plexus Injuries
Injuries to the brachial plexus in the nerves and shoulder girdle region lead to a loss of motor and sensory function, along with pain and instability in the shoulder.
The signs and symptoms vary based on the injury mechanism and the nature and extent of neurological involvement. There are two modes of injury: 1) acute direct trauma, and 2) repetitive motion or overuse. Transient compression, stretch, or traction (neuropraxia) result in sensory and motor signs lasting from days to weeks. Damage to the axon (axonotmesis) without disrupting the nerve framework may produce similar symptoms.
Recovery time is delayed and relies on axon regrowth distally from the injury site. Laceration or disruption of the entire nerve with complete loss of framework (axonotmesis) represents the most severe form of nerve injury. Function restoration depends on regrowth of the nerve distal to the injury site, but total disruption of the axon sheath may hinder recovery. Electrodiagnostic studies (EDX) are the most commonly used diagnostic method for analyzing nerve injuries. These studies should be employed when necessary as an extension of the history and clinical examination.
Slowing of motor nerve conduction velocities due to demyelination can be localized to identify regions of entrapment and injury. Denervation demonstrated on the electromyographic portion indicates motor axonal or anterior horn cell loss. Studies should be conducted three to four weeks following injury or symptom description. If symptoms persist for more than three to four weeks, studies may be conducted immediately after the initial evaluation (defined as the first encounter with the physician, not the date of injury). Serial studies may be warranted if initial studies are negative and can also assist in gauging prognosis.
Limb temperature affects nerve conduction velocities. In cases of significant slowed conduction, it is recommended to follow the standard of the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM), including temperatures. It is preferable that EDX in the outpatient setting be performed and interpreted by physicians certified in neurology or physical medicine and rehabilitation. There are six relatively common nerve injuries to the shoulder girdle, each of which will be addressed separately.
Brachial Plexus
Brachial Plexus Formation
The Brachial Plexus is created by the nerve roots of C5-C8 and T1, exiting the cervical spine and traversing the scalene musculature. Upon leaving the scalene musculature, they form trunks, divisions, and cords at the clavicle level, ultimately shaping the peripheral nerves of the arm.
History and Injury Mechanism
Direct brachial plexus injury leads to extensive sensory and motor loss. Various factors, including direct trauma, shoulder subluxation, clavicular fractures, shoulder depression, and head deviation away from the arm, can result in diverse brachial plexus lesions. It is crucial to distinguish these injuries from the acquired (nonwork-related) Parsonage-Turner Syndrome, a syndrome of brachial plexus neuritis.
Physical Examination Findings
Physical findings may involve inspecting for trauma or deformity, identifying sensory loss, demonstrating weakness corresponding to the injury’s severity and anatomy, and experiencing pain during the mechanism of injury’s recreation.
Laboratory Tests
Generally, laboratory tests are not indicated. They are recommended selectively in patients suspected of having a systemic illness or disease.
Testing Procedures
Testing procedures may encompass electrodiagnostic studies (EDX). If these studies fail to localize and provide sufficient information, additional insights may be gained from MRI and/or myelography. These studies are employed to differentiate root avulsion from severe brachial plexus injuries. Evaluation may also involve an apical lordotic chest x-ray.
Non-Operative Treatment Approaches (Brachial Plexus)
For closed injuries, observation is the preferred approach. Repeat electrodiagnostic studies may aid in monitoring recovery. In moderate to severe presentations, a sling may be indicated.
Rehabilitation through Procedures in Section E: Therapeutic Procedures – NonOperative
The rehabilitation involves employing the procedures outlined in Section E, specifically focusing on non-operative therapeutic measures.
Medications in Treatment
Medications, such as analgesics, nonsteroidal anti-inflammatories, antidepressants, and anticonvulsants (e.g., gabapentin), may be deemed necessary. Steroids may be prescribed to mitigate the inflammatory response. Narcotics may be indicated in acute situations and should be prescribed as warranted for limited durations.
Operative Procedures for Brachial Plexus
In cases of open injuries, exploration may be considered if there is inadequate progress with a conservative approach. For closed injuries, exploration is justified if there is documented progressive weakness and loss of function after 4-6 months of conservative care.
Post-Operative Procedures for Brachial Plexus
Post-operative procedures involve an individualized rehabilitation program established through communication among the physician, surgeon, and therapist. This program initiates with 4-6 weeks of rest, followed by a gradual increase in motion and strength.
Axillary Nerve
Axillary Nerve Origin and Function
The Axillary Nerve arises from the 5th and 6th cervical roots, encircling the shoulder. It provides motor branches to the teres minor and the three heads of the deltoid, offering sensation to the lateral aspect of the proximal arm at the deltoid level.
History and Injury Mechanism
Injury mechanisms involve direct injury, penetrating wounds to the shoulder, and upward pressure on the axilla. Axillary nerve injuries can also result from fractures of the surgical neck of the humerus, dislocation of the shoulder, and shoulder surgery.
Physical Examination Findings
- Weakness and atrophy of the deltoid muscle
- Loss of strength in abduction, flexion, and extension of the shoulder
- Sensory loss over the upper arm
Laboratory Tests
Generally not indicated, but recommended selectively in patients suspected of having a systemic illness or disease.
Testing Procedures: Electrodiagnostic Studies
Recommended selectively for patients with persistent symptoms.
Non-Operative Treatment Approaches
- Rehabilitation using procedures outlined in Section E: Therapeutic Procedures – Non-Operative
- Medications such as analgesics, nonsteroidal anti-inflammatories, antidepressants, and anticonvulsants may be indicated. Narcotics may be rarely indicated acutely.
Operative Procedures
Usually not necessary since most injuries to the axillary nerve result from stretch and/or traction. Surgery may be considered in select patients after four to six months with electrodiagnostic studies showing ongoing enervation and loss of function.
Post-Operative Procedures
Involve an individualized rehabilitation program established through communication among the physician, surgeon, and therapist. This program begins with four to six weeks of rest, followed by a gradual increase in motion and strength.
Long Thoracic Nerve
Long Thoracic Nerve Formation
The Long Thoracic Nerve is composed of the cervical fifth, sixth, and seventh roots. It traverses the border of the first rib and descends along the posterior surface of the thoracic wall to the serratus anterior.
History and Injury Mechanism
Injury may result from direct trauma to the posterior triangle of the neck or chronically repeated or forceful shoulder depression. Repeated forward arm motion, as well as nerve stretch or compression with abducted arms, can lead to dysfunction of the long thoracic nerve.
Physical Examination Findings (Long Thoracic Nerve)
- Dull ache in the shoulder region without sensory loss
- Scapular deformity and/or winging may be described by the patient or family
- Serratus anterior (scapular winging) may be demonstrated by asking the patient to flex and lean on their arms, such as against a wall, and/or the examiner resisting protraction.
Laboratory Tests
Generally not indicated, but recommended selectively in patients suspected of having a systemic illness or disease.
Testing Procedures: Electrodiagnostic Studies
Recommended selectively for clinically indicated patients. Indications include when signs or symptoms persist, and electrodiagnostic studies are used to define the anatomy and severity of the injury. Side-to-side comparisons of the nerve can confirm the diagnosis and exclude more widespread brachial plexus involvement.
Non-Operative Procedures
- Rehabilitation using procedures outlined in Section E: Therapeutic Procedures – NonOperative.
- Medications, such as analgesics, nonsteroidal anti-inflammatories, antidepressants, and anticonvulsants, may be indicated. Narcotics may be rarely indicated acutely.
Operative Procedures
Recommended in very select patients as clinically indicated. Operative procedures, such as scapular fixation, may be recommended, but only in the most severe cases with documented significant loss of function.
Post-Operative Procedures
Involve an individualized rehabilitation program established through communication among the physician, surgeon, and therapist. This program begins with eight to ten weeks of rest, followed by a gradual increase in motion and strength.
Musculocutaneous Nerve
Musculocutaneous Nerve Origin and Function
The Musculocutaneous Nerve originates from the fifth and sixth cervical roots. It innervates the coracobrachialis, biceps, and brachialis muscles, providing sensation to the lateral aspect of the forearm. Nerve injury can result from trauma, including surgery, or penetrating wounds to the brachial plexus, coracobrachialis, and shoulder.
History and Injury Mechanism
- Most commonly, a stretch/traction injury occurs due to forceful elbow extension inducing nerve dysfunction.
- Trauma can affect the sensory component (lateral antebrachial cutaneous nerve), leading to the loss of sensation in the forearm.
Physical Examination Findings
- Pain in the arm
- Weakness and atrophy in the biceps and brachialis
- Sensory loss over the lateral aspect of the forearm (not always present)
- Attenuation or loss of the biceps deep tendon reflex
Laboratory Tests
Generally not indicated, but recommended selectively in patients suspected of having a systemic illness or disease.
Testing Procedures: Electrodiagnostic Studies
Recommended selectively for clinically indicated patients. Indications include when signs or symptoms persist. Side-to-side comparisons of the motor and sensory components of the nerve may be useful, as standard norms are not always reliable.
Non-Operative Treatment Approaches
- Rehabilitation using procedures outlined in Section E: Therapeutic Procedures – NonOperative.
- Medications, such as analgesics, nonsteroidal anti-inflammatories, antidepressants, and anticonvulsants, may be indicated. Narcotics may be rarely indicated.
Operative Procedures
Recommended selectively for clinically indicated patients. Operative procedures are usually not necessary unless there is increasing loss of function over four to six months and/or a laceration to the nerve has been identified.
Post-Operative Procedures
Involve an individualized rehabilitation program established through communication among the physician, surgeon, and therapist. This program begins with eight to ten weeks of rest, followed by a gradual increase in motion and strength.
Spinal Accessory Nerve
Spinal Accessory Nerve Overview
The Spinal Accessory Nerve is the eleventh cranial nerve, responsible for innervating the ipsilateral sternocleidomastoid and trapezius muscles. These muscles play a crucial role in scapular control and, consequently, shoulder function.
History and Injury Mechanism
- Mechanism of Injury: Direct trauma to the posterior neck, forceful shoulder compression downward, and/or deviation of the head away from the traumatized shoulder can result in nerve injury. Surgical procedures in the posterior neck can also disrupt the nerve.
Physical Examination Findings
- Pain in the shoulder
- Weakness or paralysis of the trapezius, evident as winging with the arms abducted
- Drooping of the shoulder
Laboratory Tests
Generally not indicated but recommended selectively in patients suspected of having a systemic illness or disease.
Testing Procedures: Electrodiagnostic Studies
Recommended selectively for clinically indicated patients. Indications include when signs and symptoms persist. Electrodiagnostic studies define the anatomy and severity of the injury; side-to-side comparisons of the nerve can confirm the diagnosis. Radiographic procedures may be necessary to exclude lesions at the base of the brain or upper cervical spine.
Non-Operative Treatment Approaches
- Rehabilitation using procedures outlined in Section E: Therapeutic Procedures – NonOperative.
- Medications, such as analgesics, nonsteroidal anti-inflammatories, antidepressants, and anticonvulsants, may be indicated. Narcotics may be rarely indicated acutely.
Operative Procedures
Recommended selectively for clinically indicated patients. Operative procedures are usually not necessary unless increased loss of function over four to six months has been documented and/or a laceration to the nerve has been identified.
Post-Operative Procedures
Involve an individualized rehabilitation program established through communication among the physician, surgeon, and therapist. This program begins with eight to ten weeks of rest, followed by a gradual increase in motion and strength.
Suprascapular Nerve
Suprascapular Nerve Overview
The Suprascapular Nerve originates from the fifth and sixth cervical roots, specifically the superior trunk of the brachial plexus. It innervates the supraspinatus and infraspinatus muscles of the rotator cuff.
History and Injury Mechanism
- Mechanism of Injury: Supraclavicular trauma, stretch, and friction through the suprascapular notch or against the transverse ligament at the notch can lead to nerve injury. Repetitive arm use has, on occasion, been shown to cause traction to the nerve.
Physical Examination Findings
- Pain at the shoulder
- Wasting at the supraspinatus and/or infraspinatus muscles with weakness
- Tinel’s sign can help elicit a provocative pain response.
Laboratory Tests
Generally not indicated but recommended selectively in patients suspected of having a systemic illness or disease.
Testing Procedures: Electrodiagnostic Studies
Recommended selectively for clinically indicated patients. Indications include when signs and symptoms persist. Side-to-side comparisons may be useful since standard norms are not always reliable. If a mass lesion at the suprascapular notch is suspected, an MRI may be indicated.
Non-Operative Treatment Approaches
- Rehabilitation using procedures outlined in Section E: Therapeutic Procedures – NonOperative.
- Medications, such as analgesics, nonsteroidal anti-inflammatories, antidepressants, and anticonvulsants, may be indicated. Narcotics may be rarely indicated acutely.
Operative Treatment Approaches
Recommended selectively for clinically indicated patients. Operative treatment involving surgical release at the suprascapular notch or spinoglenoid region is warranted based on the results of electrodiagnostic studies and/or the absence of improvement with conservative management.
Post-Operative Procedures
Involve an individualized rehabilitation program established through communication among the physician, surgeon, and therapist. This program begins with eight to ten weeks of rest, followed by a gradual increase in motion and strength.
