• Clinical science

Radial neuropathies


Radial neuropathies are conditions caused by acute or chronic injury to the radial nerve. Clinical presentations vary with the mechanism, site, and extent of nerve injury. The radial nerve arises from the posterior cord of the brachial plexus, which comprises cervical roots C5–T1. Within the upper extremity, the radial nerve has lateral cutaneous sensory branches and innervates extensors. When injured, radial neuropathies are therefore characterized by sensory symptoms of pain, paresthesia, and numbness, as well as motor symptoms of weakness of extension at the elbow, wrist (“wrist drop”), and/or fingers. Several risk factors are associated with subtypes of radial neuropathies, including crutch use, intoxication, fracture of the humerus or radius, use of tight watch bands or handcuffs, and repetitive pronation and supination. The patient history and examination, including Tinel's sign, may be sufficient for diagnosis in some cases, but x-ray is necessary in the presence of trauma, and electrodiagnostics, though less useful than in carpal tunnel syndrome, may be considered if symptoms persist. Conservative management, consisting of local corticosteroid injections and counseling to reduce risk factors, is typically the treatment of choice in nontraumatic cases. Surgical decompression, with approach varying by location, may be considered in refractory cases.



Clinical features

Site of lesion Sensory symptoms Motor symptoms
  • All below
  • All below
  • Wrist drop
    • Paralysis or weakness of the hand and finger extensors (decreased grip strength)
    • The patient cannot extend their hand at the wrist joint.
Elbow (radial tunnel)
  • Sometimes weakness of extension and supination, secondary to pain (not to missing innervation!)
Deep forearm (proximal posterior interosseous nerve)
  • None
  • Paralysis of the finger extensors (no true wrist drop!)
Superficial forearm and wrist (superficial radial nerve)
  • Deficits on the radial side of the dorsum of the hand (thumb, index finger, and the radial half of the middle finger)
  • None

The higher (more proximal) the lesion, the greater the number of extensor muscles involved!



  • History:
    • Inquire about risk factors, including substance use, trauma, and causes of compression.
    • Ask the patient to describe the timeline of symptoms, history of similar symptoms, and associated symptoms such as joint pain.
  • Physical examination: Focus the exam on the most proximal location of injury, if known (see “Clinical Features”)



  • The treatment of choice depends on the severity and persistence of symptoms.
  • Conservative therapy
  • Surgical therapy in severe and treatment-resistant cases: nerve decompression, neurorrhaphy, nerve transplantation, tendon transfer
  • Orthopedic repair of fractures, dislocations, or other traumatic injury


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  • 3. Stern M. Radial Nerve Entrapment. In: Radial Nerve Entrapment. New York, NY: WebMD. http://emedicine.medscape.com/article/1244110. Updated September 13, 2016. Accessed April 7, 2017.
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last updated 11/09/2020
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