It is the major peripheral nerve of the upper limb. It runs down the arm where it passes on the medial side of the arm between the brachialis and the biceps brachii. The majority of the muscles in the forearm are controlled by median nerve. For example, it controls abduction of the thumb, flexion of hand at wrist, flexion of digital phalanx of the fingers. Due to its importance, it is also called the eye of the hand. Median nerve injury can be classified into two groups: high and low median nerve injuries. If the lesion involves the elbow and forearm areas, this will be high median nerve injury. If the lesion involves the wrist, this will be low median nerve injury.
Median nerve injury is usually caused by deep, penetrating injuries to the arm, forearm, or wrist.
- Ape-hand deformity: Inability to abduct and oppose the thumb due to paralysis of the thenar muscles.
- Loss of sensation in the thumb, index finger, long finger, and the radial aspect of the ring finger
- Impairment and inability in forearm pronation and wrist and finger flexion
- Regular activities of daily living such as brushing teeth, and writing could become very hard with this medical condition
Common Physical Therapy interventions in the treatment of median nerve injury include:
- Manual Therapeutic Technique (MTT): hands on care including soft tissue massage, stretching and joint mobilization by a physical therapist to improve alignment, mobility and range of motion. The use of mobilization techniques also helps to modulate pain.
- Therapeutic Exercises (TE) including stretching and strengthening exercises to regain range of motion and strengthen muscles of the arm, forearm or wrist area to support, stabilize and decrease the stresses place on median nerve.
- Neuromuscular Reeducation (NMR) to restore stability, improve movement techniques and mechanics of the involved arm, forearm or wrist area. It also reduces stress on the joint surfaces in daily activities.
- Modalities including the use of ultrasound, electrical stimulation, ice, cold, laser and others to decrease pain and inflammation of the involved joint.
- Avoiding the activities that produce the pain or stress the involved arm, forearm or wrist area is the first line of treatment.
- RICE: Rest, Ice, Compression, Elevation should be used to reduce the stress on the median nerve.
- NSAIDS (Non steroidal anti-inflammatory drugs) to reduce pain and inflammation.
- Immobilization, strapping or bracing may be beneficial to rest, and promote recovery.
- Injection of steroids may be indicated to reduce inflammation
- In severe recurrent conditions, surgery may be indicated. Surgery involves excising the tissue or removing parts of the bone compressing the nerve
Occupation therapy and wearing splints could help a lot in prevention of recurrence of median nerve injury. Although it is not possible to totally inhibit trauma to arm and wrist, patients may decrease the amount of compression by keeping proper actions during repetitive activities. Also, strengthening and rising flexibility will decrease the risk of nerve compression.
