Why is my forearm feeling heavy today, given my history of lateral wrist drop and radial nerve injury, when yesterday the heaviness was in my upper arm?

Migrating Heaviness from Upper Arm to Forearm with Radial Nerve Injury History

Your migrating heaviness from upper arm yesterday to forearm today most likely represents progressive radial nerve dysfunction, and you need urgent clinical evaluation with nerve ultrasound or MRI to determine if there is worsening compression requiring immediate intervention.

Understanding Your Symptom Pattern

The migration of heaviness distally along your arm over 24 hours is concerning for progressive radial nerve compromise. Given your history of radial nerve injury and wrist drop, this pattern suggests either:

• Worsening compression at an existing site of nerve injury 1, 2
• New compression developing at a different anatomical location along the radial nerve pathway 3
• Evolving nerve dysfunction from repetitive arm use or positioning 4

The radial nerve can be compressed at multiple sites from the upper arm (spiral groove) down through the forearm (radial tunnel), and symptoms can migrate as different portions of the nerve become affected 1, 3.

Critical Red Flags Requiring Immediate Attention

You should seek urgent evaluation if you experience:

• Progressive motor weakness, particularly worsening wrist drop or new finger extension weakness 2, 3
• Rapidly increasing numbness over the dorsal hand and forearm 5, 2
• Complete inability to extend the wrist or fingers 2, 4

These indicate advancing nerve injury that may require urgent surgical decompression to prevent permanent deficit 3.

Recommended Diagnostic Approach

Start with clinical examination focusing on:

• Specific location of heaviness using the "rule of nine" test to map the exact distribution 1
• Testing third finger and wrist extension strength 1
• Assessing sensation over the dorsal forearm and hand 5, 2

If examination confirms radial nerve involvement, obtain imaging:

• Nerve ultrasound is the preferred initial study for confirming radial nerve compression and identifying the exact site 4
• MRI without contrast can show muscle edema or atrophy along the posterior interosseous nerve distribution if ultrasound is inconclusive 1, 6

The American College of Radiology recommends MRI without IV contrast for suspected soft tissue and nerve injuries when radiographs are normal 7.

Immediate Management Strategy

Activity modification is essential:

• Immediately cease any repetitive arm activities, particularly overhead work or repetitive pronation movements 4, 3
• Avoid positions that compress the radial nerve, including arm abduction greater than 90° or prolonged elbow flexion 7

Medical treatment should include:

• Systemic corticosteroids for acute compression (as used successfully in documented cases of acute radial neuropathy) 4
• NSAIDs for pain control 1
• Vitamin B supplementation 5

Physical therapy should be initiated once acute compression is addressed 1, 5.

Prognosis and Recovery Timeline

With traumatic or compression-related radial nerve lesions, prognosis is generally good if treated promptly 2. Recovery timelines vary:

• Mild compression: Improvement within days to weeks with activity modification 4
• Moderate injury: 60 days for complete motor recovery (as documented in perioperative cases) 5
• Severe compression: May require surgical decompression, with 67-93% achieving complete symptom relief 1

Recovery is faster when:

• Compression duration is shorter 3
• Repetitive aggravating activities are ceased 3
• Treatment is initiated rapidly 5

Common Pitfalls to Avoid

Do not dismiss this as simple muscle fatigue - migrating neurological symptoms warrant investigation 2, 3.

Do not delay imaging if symptoms progress or fail to improve within 48-72 hours of activity modification 4, 3.

Do not confuse with lateral epicondylitis - radial tunnel syndrome and lateral elbow pain can mimic each other, but your history of radial nerve injury makes nerve pathology more likely 3.