What is Cubital tunnel syndrome?
Compression of the ulnar nerve is medically termed as cubital tunnel syndrome. Due to compression of ulnar nerve leads to the tingling sensation or numbness in the little finger and ring finger with pain and weakness in the affected upper limb.
This medical condition is termed so, because of the anatomical location of the ulnar nerve. Trough cubital tunnel, the ulnar nerve moves and extends under the medial epicondyle (termed as “funny bone.”) and prior to travel towards the brain, this nerve enters into an added tunnel named as a Guyon’s canal. There is a very close association between ulnar nerve with underlying muscles. (1,2)
The different factors which influence the cubital tunnel syndrome are as follows:
Due to incorrect lying posture during sleep can cause prolonged bending at the elbow joint and pressure is generated in the ulnar nerve.
Sometimes extended pressure is generated cubital tunnel syndrome, as ulnar nerve has very little padding. During the body rest on the particular hand or may little or ring finger becomes pressed due to wrong sleeping posture, as the ulnar nerve gets compressed due to extended pressure.
Movement of the ulnar nerve
The ulnar nerve is not fixed in its position and can move forward and backward direction. Therefore, bending of the elbow joint can cause sliding of the ulnar nerve from medial epicondyle. This cause irritation of the ulnar nerve and pain and other symptoms arise.
Any joint inflammatory condition which occurs due to retention of the fluid and this can cause compression of the ulnar nerve.
Any accidental injury directly hits ‘ funny bone’ or elbow joint can hurt the ulnar nerve.
The risk factors which influence the different reasons behind the compression of the ulnar nerve:
- Elbow fracture or dislocation
- Joint disorders like arthritis or any other bone spurs which affects medial epicondyle
- Inflammation of the elbow joint
- Cyst formation close to the elbow joint
- Prolonged, repetitive actions that involve the elbow to be bent or contract continuously
Sign and symptoms
The ulnar nerve provides sensation to the ring finger and the little finger. It also regulates maximum number of the small muscles present in the upper limbs that assist in the fine actions, and some of the superior muscles in the hand that assist to make a sturdy grip. Therefore, all the symptoms arise in cubital tunnel syndrome affect mainly in the upper extremities. The following sign and symptoms are included in the cubital tunnel syndrome:
- One of the common symptom is tingling sensation and numbness in the little finger or in the ring finger, though this symptom is not continuous. It is prominent during prolonged bending of elbow joint, which include holding the phone or driving a motor car foe prolonged period. Even due to numbness nocturnal awakening is frequent for some individuals.
- Difficulty in holding things or finger movement, specifically ring finger and little finger become painful or sensation of pricking of a needle like feeling is generated due to falling asleep in bending position of the elbow or lying down based on the ring finger and little finger.
- Weak griping power which affects holding of cricket ball or manipulating the position of the things. Trouble in finger management during play an instrument or typing can develop during the more rigorous nerve compression.
- Pain in the whole upper extremities.
- Generalized weakness and clumsy feeling may generate. (1,2)
It is always advisable to consult doctors if prolonged or repetitive cubital tunnel syndrome occurs, because it may cause temporary or permanent disabling due to muscle wasting. (2)
Initial diagnosis is started by discussing with sign and symptoms. Doctor even ask about medical history, general health, occupation, activities, co-morbidity and medications taken by the patient. This discussion is further proceeding to physical examinations, which is conducted by a doctor to rule out the severity of the condition. The steps usually followed during physical examination are:
- Tapping on the funny bone, which can cause irritation in the ulnar nerve and resultant shock is produced in the little finger and ring finger, though it is typical that taping can generate shock into the little finger and ring finger.
- The checking of the position of the ulnar nerve in the bending position of the ulnar nerve.
- Ask to move wrist, elbow, shoulder and neck, to check the symptoms.
- Test out the sensation and griping power of the fingers and hands.
Doctor usually orders wrist and elbow X-ray to check the involvement of the bones, as the joint disorder like arthritis or bone spur can irritate the ulnar nerve.
Nerve conduction studies
The nerve conduction studies help to rule out the functionality of the ulnar nerve and also detect the compression location. In nerve conduction tests, the impulse transmission is measured. This test also helpful to determine the muscle damage related to nerve compression.
For confirmatory test, magnetic resonance imaging (MRI) and ultrasound have been ordered. Theses imaging tools are beneficial for presenting the lesions like swelling of the nerve fibers (ganglions), any benign tumor in the nerve (neuromas) or regional ulnar arterial inflammation (aneurysms) in Guyon’s canal causing compression of the ulnar nerve. (2,3,4)
Treatment is divided into three segments, natural therapy, non surgical therapy and surgical therapy.
Usually daily activities may hamper due to the cubital tunnel syndrome, therefore, for symptomatic relief, following measures can helpful:
- Do not perform such works, which need prolonged bending of the elbow joint.
- During typing for prolonged period , avoid respite elbow on the armrest
- Avert the activities such as leaning on elbow, which put pressure inside the hand. The activities include driving a motor vehicle with resting on the arm on the open window.
- Maintain the proper hand posture during sleeping , like to keep straight elbow when you are in the lying position. For this wrapping of a towel or wearing an elbow pad at backward direction can help to maintain the proper posture.
Non surgical therapy
Usually non-steroidal anti-inflammatory drugs ((NSAIDs) like ibuprofen are useful to relieve pain. Sometimes, doctors can also prescribe steroidal drug due to pain is uncontrollable with NSAIDS.
Wearing of splint
The wearing of a splint can helpful to maintain the straight positioning of the elbow at the night during sleeping.
Nerve gliding exercises
Stretching of the affected upper limb and rotation, inward & outer ward abduction and adduction movement of the wrist joint is thought to be helpful to reduction of the cubital tunnel syndrome.
Surgical therapy has several complications like holing of ulnar nerve, damage to the associated ligaments, constant weakness, neuronal damage in the associated nerve tissues, infection, haematoma, prolonged numbness, etc. Therefore surgical intervention is not recommended frequently. But if natural therapy and nonsurgical therapy are not effective, then surgical intervention is recommended. Through surgical intervention the increased pressure on the ulnar nerve is released by widening the cubital tunnel. (2,4)
1. Cubital Tunnel Syndrome, American Societyfor Surgery of the Hand; Retrieve from: http://www.assh.org/handcare/hand-arm-conditions/cubital-tunnel
2. Jay D. Keener , eorge S. Athwal; Stuart J. Fischer, J. Michael Wiater, (2015); Ulnar Nerve Entrapment at the Elbow (Cubital Tunnel Syndrome); c http://orthoinfo.aaos.org/topic.cfm?topic=a00069
3. Jennifer Robinson (2014); Cubital and Radial Tunnel Syndrome; Retrieve from: http://www.webmd.com/pain-management/cubital-radial-tunnel-syndrome?page=3
4. Steven Cutts; Cubital tunnel syndrome; Postgrad Med J. 2007 Jan; 83(975): 28–31; Retrieve from : http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2599973/