Ulnar nerve entrapment
Description of condition
The ulnar nerve is one of three main nerves that travel to the arm and hand from the spinal cord. Along the route to the arm and hand there are various areas in which the ulnar nerve can be entrapped, leading to pain and irritation of the ulnar nerve. Areas where the nerve is commonly entrapped are behind the collarbone, at the elbow and at the wrist.
When entrapment occurs at the elbow it is referred to as “cubital tunnel syndrome”. Entrapment at the wrist is referred to as “Guyon’s canal syndrome”.
Causes
Compression of the ulnar nerve at the elbow can be caused by various mechanisms. The nerve is particularly vulnerable at the elbow as it is close to the skin surface with minimal protection by soft tissue.
- Direct hit/blow to the elbow (“hitting your funny bone”)
- Prolonged pressure on your elbow (e.g. when working at a computer with your elbow on the table or armrest of the chair), putting strain on the nerve where it runs over the boney prominence of the elbow.
- Swelling around the elbow
Some causes for compression of the ulnar nerve at the wrist are:
- Ganglions
- Fracture of the hamate wrist bone
- Constant external compression/trauma (e.g. on handle bars of a bicycle)
Symptoms
- Pins and needles/numbness of the little finger and half of the ring finger on both sides.
- Weak grip and poor coordination of fingers. Difficulty performing tasks like typing.
- With continuous compression, muscle wasting may occur.
- Claw deformity can occur with prolonged compression and subsequent damage to the ulnar nerve; hyperextension of knuckles of little finger and ring finger with flexion of first joint in little finger and ring finger.
Treatment options
Conservative management may be indicated by the treating doctor if the condition has not progressed too far. If the symptoms are persistent and cause functional limitations, surgery may be indicated.
Conservative management
When consulting the hand therapist you will be provided with:
Nerve gliding exercises
Nerve gliding exercises may also be performed with the aim to release the nerve from where it is being compressed.
Splinting
Splinting may be indicated to prevent continuous strain on the ulnar nerve together with position changes in daily activity may be indicated.
Surgical management
If the nerve is continuously irritated by a boney prominence, an anterior transposition (relocation of the nerve) or medial epicondylectomy (removing the boney prominence) may also be indicated.
When the entrapment occurs in the guyon’s canal the ligament can also be released to create more space for the nerve to glide. If the entrapment is caused by a ganglion or cyst, this will have to be removed in order to allow more gliding space for the nerve.
It is important to note that healing of the nerve tissue takes time. Surgery should provide relief from the numbness, pain, weakness or tingling sensation, but it may take several months for improvement to reach an optimal level.
Post-operative management
- You will be immobilized in a post-operative dressing for 8 – 14 days.
- Your stitches may be either dissolvable or the hand therapist/doctor will remove them after 10 – 14 days.
- Although your post-operative dressing is usually removed after 8 – 14 days you are not allowed to lift any heavy weights or start using your hand or wrist in any strenuous tasks. Care should be taken to perform light functional tasks within limited pain thresholds for the first 4 – 6 weeks after surgery.
Aims of hand therapy
- Management of swelling and wound care.
- Scar Management – to prevent the scar from getting stuck to the nerve.
- Nerve gliding exercises – to prevent the nerve from getting entrapped in the scar tissue.
- Splinting for functional participation in activities of daily living.
- Mobilisation of the hand, wrist and elbow.
- Sensory re-education/desensitization.
- Strengthening exercises.
*The above text is for information purposes only and should not be seen as health advice. Please consult with your medical practitioner should you require health advice or medical treatment.