What could be causing severe weakness and involuntary coiling of the wrist in an adult with no pain, possibly due to repetitive strain or overuse?

Severe Wrist Weakness with Involuntary Coiling (No Pain)

You need urgent neurological evaluation for suspected peripheral nerve injury or neuropathy affecting the wrist extensors, most likely radial nerve palsy or severe median/ulnar nerve dysfunction causing wrist drop and abnormal posturing.

Immediate Clinical Assessment

The combination of severe weakness and involuntary coiling (abnormal posturing) without pain suggests a neurological rather than musculoskeletal etiology:

• Wrist drop from radial nerve palsy presents as inability to extend the wrist with the hand falling into flexion, which may appear as "coiling" 1
• Severe weakness without pain is atypical for tendinopathy or overuse syndromes, which typically cause pain with functional loading 2, 1
• Nerve compression syndromes can cause weakness and abnormal hand positioning, particularly carpal tunnel syndrome (median nerve) or ulnar nerve compression, though these usually have associated sensory symptoms 3

Diagnostic Workup

Start with plain radiographs of the wrist to rule out fracture, dislocation, or bone pathology that could be compressing nerves 4:

• Radiographs are the appropriate first-line imaging study for wrist complaints 4
• Look for fractures, joint malalignment, or masses that could cause nerve compression 4

If radiographs are normal, proceed to nerve conduction studies and EMG to identify the specific nerve involved and severity of dysfunction:

• This is critical for differentiating between radial, median, or ulnar nerve pathology 1
• Helps determine if the lesion is at the wrist, forearm, or more proximal 3

MRI without IV contrast may be indicated if structural nerve compression is suspected:

• MRI can identify masses, ganglion cysts, or soft tissue abnormalities compressing nerves 4, 2
• Useful for evaluating tendon pathology if tenosynovitis is contributing to nerve compression 3

Critical Differential Diagnoses

Radial nerve palsy (wrist drop):

• Most common cause of inability to extend wrist with hand falling into flexion 1
• Can result from compression at various sites along the nerve course
• May occur from repetitive activities or prolonged pressure

Severe carpal tunnel syndrome:

• Advanced median nerve compression can cause severe weakness and thenar atrophy 3
• Typically has sensory symptoms, but severe cases may present primarily with motor weakness 3

Monomelic ischemic neuropathy:

• Acute neuropathy with global muscle pain and weakness, though this typically presents with a warm hand and palpable pulses 4
• Less likely given no mention of vascular access or recent surgery 4

Common Pitfalls to Avoid

• Do not assume this is simple overuse tendinopathy - the absence of pain with severe weakness points to neurological pathology, not tendon disease 2, 1
• Do not delay neurological referral - progressive nerve compression can lead to permanent motor deficits if not addressed promptly 3
• Do not confuse with hand ischemia - ischemic steal syndrome presents with pain, coldness, and color changes, not isolated weakness 4

Urgent Management

Immediate splinting in neutral position to prevent contracture while awaiting definitive diagnosis 5:

• Immobilize the wrist to minimize further nerve irritation 5
• Avoid positions that increase nerve compression 1

Urgent referral to neurology or hand surgery within 24-48 hours for definitive diagnosis and treatment 5:

• Nerve decompression surgery may be required if structural compression is identified 1, 3
• Early intervention prevents irreversible nerve damage 3