Nerve Injuries to the Hand & Wrist

Overview

Nerve injuries to the hand and wrist can significantly impact hand function, leading to pain, numbness, weakness, and loss of dexterity. These injuries can result from trauma, repetitive stress, or medical conditions affecting the nerves. The three primary nerves that can be affected are the median nerve, ulnar nerve, and radial nerve.

Causes

Nerve injuries to the hand and wrist can arise from various causes, including:

• Trauma: Lacerations, fractures, or dislocations that damage the nerves.
• Repetitive Motion: Activities causing repetitive stress or pressure on the nerves, such as typing, using tools, or playing instruments.
• Compression: Conditions like carpal tunnel syndrome (median nerve) or ulnar tunnel syndrome (ulnar nerve) that compress the nerves.
• Medical Conditions: Diabetes, rheumatoid arthritis, and other conditions that affect nerve health.

Types of Nerve Injuries

The three main nerves in the hand and wrist can be affected differently:

1. Median Nerve Injuries:

   • Carpal Tunnel Syndrome: Compression of the median nerve as it passes through the carpal tunnel in the wrist, causing numbness, tingling, and weakness in the thumb, index, and middle fingers.
   • Lacerations or Trauma: Direct injury to the median nerve can result in loss of sensation and motor function in the affected areas.

2. Ulnar Nerve Injuries:

   • Ulnar Tunnel Syndrome (Guyon’s Canal Syndrome): Compression of the ulnar nerve at the wrist, leading to numbness and tingling in the ring and little fingers.
   • Cubital Tunnel Syndrome: Compression of the ulnar nerve at the elbow, affecting the hand and fingers.
   • Trauma: Direct injury to the ulnar nerve can cause significant functional impairments.

3. Radial Nerve Injuries:

   • Radial Tunnel Syndrome: Compression of the radial nerve in the forearm, leading to pain and weakness in the hand and wrist.
   • Saturday Night Palsy: Compression of the radial nerve in the upper arm, often from prolonged pressure, causing wrist drop and inability to extend the fingers.

Symptoms

Symptoms of nerve injuries in the hand and wrist depend on the specific nerve affected and may include:

• Pain: Sharp or burning pain along the path of the affected nerve.
• Numbness and Tingling: Loss of sensation or “pins and needles” feeling in the affected area.
• Weakness: Difficulty gripping or holding objects, muscle weakness, or muscle wasting in severe cases.
• Loss of Coordination: Impaired fine motor skills and dexterity.

Diagnosis

Diagnosis involves a comprehensive evaluation, including:

• Medical History and Physical Examination: Assessment of symptoms, injury history, and physical examination to identify signs of nerve damage.
• Nerve Conduction Studies and Electromyography (EMG): Tests to evaluate the electrical activity and function of the nerves and muscles.
• Imaging Studies: X-rays, MRI, or ultrasound to visualize the structures of the hand and wrist and identify any underlying causes of nerve compression or injury.

Treatment

Treatment options depend on the severity and cause of the nerve injury and may include:

• Non-Surgical Treatment:

  • Rest and Activity Modification: Avoiding activities that aggravate symptoms and allowing time for healing.
  • Splinting or Bracing: Using splints or braces to immobilize the affected area and reduce pressure on the nerve.
  • Medications: Pain relievers, anti-inflammatory drugs, or corticosteroid injections to manage pain and inflammation.
  • Physical Therapy: Exercises to improve strength, flexibility, and function, and techniques to modify activities that contribute to symptoms.

• Surgical Treatment:

  • Decompression Surgery: Relieving pressure on the affected nerve by enlarging the surrounding structures, such as in carpal tunnel release or ulnar nerve decompression.
  • Nerve Repair or Grafting: Repairing severed nerves or using grafts to restore nerve continuity in cases of severe trauma.
  • Neurolysis: Removing scar tissue or adhesions around the nerve to improve function.

Prognosis

The prognosis for nerve injuries in the hand and wrist varies based on the severity of the injury and the timeliness of treatment. Early diagnosis and appropriate treatment can lead to significant improvement in symptoms and function. Severe or untreated nerve injuries may result in permanent deficits.

Prevention

Preventing nerve injuries involves taking measures to reduce risk factors:

• Ergonomic Adjustments: Modifying workstations and tools to reduce strain on the hands and wrists.
• Protective Gear: Using appropriate protective equipment during activities that pose a risk of injury.
• Proper Technique: Employing proper techniques and form in sports and physical activities to minimize the risk of injury.
• Regular Breaks: Taking regular breaks during repetitive tasks to avoid overuse injuries.