What is the treatment approach for a patient with musculocutaneous neuropathy?

Treatment of Musculocutaneous Neuropathy

Conservative management with relative rest, NSAIDs, physical therapy, and splinting should be initiated first, with surgical decompression reserved only for cases that fail conservative treatment after an adequate trial. 1

Initial Diagnostic Confirmation

Before initiating treatment, confirm the diagnosis through electrodiagnostic studies, as nerve conduction studies alone are insufficient—needle EMG examination is essential to document denervation in the biceps and brachialis muscles 2. This distinguishes musculocutaneous neuropathy from cervical radiculopathy or brachial plexus lesions that may present similarly 1.

Conservative Treatment Approach (First-Line)

Initiate conservative management for all patients unless there is complete nerve transection or compressive mass lesion:

• Relative rest from aggravating activities, particularly those involving repetitive elbow flexion or shoulder movements 1
• NSAIDs for pain and inflammation control 1
• Splinting to protect the nerve during recovery and prevent overstretching 1
• Structured physical therapy focusing on maintaining range of motion while avoiding excessive stress on the healing nerve 1

The majority of traumatic and iatrogenic musculocutaneous neuropathies (65% of cases) respond to conservative management 2.

Pharmacologic Management for Neuropathic Pain

If neuropathic pain is prominent (numbness, tingling, burning sensations), add symptomatic treatment:

• First-line options: Duloxetine (30 mg daily for 1 week, then 60 mg daily), pregabalin (target 300 mg twice daily), or gabapentin (1200-3600 mg daily in divided doses) 3
• Alternative: Tricyclic antidepressants such as nortriptyline (starting 10-25 mg at bedtime, titrating slowly) if first-line agents are ineffective or contraindicated 3

These medications address the neuropathic pain component but do not accelerate nerve recovery 3.

Special Considerations for Inflammatory Causes

If bilateral musculocutaneous neuropathy is present or there is clinical suspicion for neuralgic amyotrophy (Parsonage-Turner syndrome):

• Corticosteroid pulse therapy: Methylprednisolone 1 g daily for 5 days, followed by a slow taper over 4-6 weeks 3, 4
• This approach is supported by case reports showing complete recovery with steroid treatment in inflammatory cases 4

Bilateral absence of lateral antebrachial cutaneous nerve sensory responses strongly suggests an inflammatory etiology requiring immunosuppressive treatment 2.

Surgical Intervention Criteria

Proceed to surgical decompression only if:

• Conservative management fails after 3-6 months of adequate trial 1
• A compressive mass lesion (osteochondroma, tumor, hematoma) is identified on imaging 5
• Progressive weakness develops despite conservative treatment 1

Mass lesions should be considered in atraumatic cases that are recurrent or fail to recover, even when strenuous exercise is the apparent trigger 5.

Monitoring and Prognosis

• Reassess clinically every 4-6 weeks during conservative treatment
• Repeat electrodiagnostic studies at 3-6 months if no clinical improvement to assess for reinnervation 2
• Note that some patients may not exhibit significant weakness despite nerve injury, as other muscles (brachioradialis, supinator) can compensate for elbow flexion and supination 2

Critical Pitfall to Avoid

Do not rely solely on sensory nerve conduction studies of the lateral antebrachial cutaneous nerve—normal sensory responses do not exclude musculocutaneous neuropathy, as motor fibers may be selectively injured 4. Always perform needle EMG of the biceps and brachialis muscles to confirm the diagnosis 2.