Wrist drop

Wrist Drop

Anatomical illustration of the radial nerve and its branches.

Wrist drop, also known as radial nerve palsy, is a condition characterized by the inability to extend the wrist and fingers, leading to a "drooping" appearance of the hand. This condition is typically caused by damage to the radial nerve, which innervates the muscles responsible for wrist and finger extension.

Causes

Wrist drop can result from various causes, including:

• Compression of the radial nerve: This can occur due to prolonged pressure on the nerve, often seen in situations such as "Saturday night palsy," where the arm is compressed against a hard surface during sleep.
• Fractures: A fracture of the humerus can lead to radial nerve injury, as the nerve runs in close proximity to the bone.
• Direct trauma: Injury to the arm or forearm can directly damage the radial nerve.
• Systemic conditions: Conditions such as diabetes mellitus or lead poisoning can lead to neuropathy affecting the radial nerve.

Symptoms

The primary symptom of wrist drop is the inability to extend the wrist and fingers, resulting in a characteristic "drooping" of the hand. Other symptoms may include:

• Weakness in the wrist and finger extensors
• Numbness or tingling in the back of the hand and forearm
• Difficulty in performing tasks that require wrist extension, such as lifting objects

Diagnosis

Diagnosis of wrist drop involves a combination of clinical examination and diagnostic tests. A healthcare provider will assess the range of motion, muscle strength, and sensory function of the affected limb. Additional tests may include:

• Electromyography (EMG): To assess the electrical activity of muscles and the function of the radial nerve.
• Nerve conduction studies: To evaluate the speed and strength of signals traveling through the radial nerve.
• Imaging studies: Such as X-rays or MRI, to identify any structural causes of nerve compression or injury.

Treatment

Treatment of wrist drop depends on the underlying cause and severity of the condition. Options may include:

• Physical therapy: Exercises to strengthen the wrist and finger extensors and improve range of motion.
• Splinting: Use of a wrist splint to support the hand in a functional position and prevent contractures.
• Surgical intervention: In cases where there is significant nerve damage or compression, surgical decompression or nerve repair may be necessary.
• Medications: Pain management and treatment of underlying conditions, such as diabetes, may be required.

Prognosis

The prognosis for wrist drop varies depending on the cause and extent of nerve damage. In cases of mild compression, recovery may occur within weeks to months with appropriate treatment. However, severe nerve injury may result in prolonged recovery or permanent deficits.

Related Pages

• Radial nerve
• Peripheral neuropathy
• Nerve injury
• Physical therapy