Cubital tunnel syndrome is caused by compression of the ulnar nerve as it passes behind the inside of the elbow. It can cause numbness, pins and needles, tingling in the little and ring fingers and weakness in the hand.
Mr Robert Farnell is an experienced specialist Consultant Orthopaedic Hand and Wrist Surgeon who has been working in Leeds for over 25 years. He exclusively treats conditions affecting the adult hand and wrist, including carpal tunnel syndrome, trigger finger and thumb, thumb arthritis and Dupuytren’s disease.
What is cubital tunnel syndrome?
Cubital tunnel syndrome is compression of the ulnar nerve as it passes through the cubital tunnel behind the elbow.
The ulnar nerve is a major nerve which supplies sensation to the little finger and ring finger. It also supplies many of the small muscles in the hand.
The ulnar nerve is most commonly compressed at the elbow and less commonly at the wrist. Compression of the nerve as it passes through the tunnel behind the elbow is called cubital tunnel syndrome.
Symptoms of cubital tunnel syndrome
Symptoms are usually caused by altered sensation in the hand or weakness of the small muscles in the hand.
Common symptoms include:
- Altered feeling, pins and needles or tingling in the little finger and ring finger
- Pain in these fingers, which may radiate up the forearm
- Weakness in the small muscles of the hand
- Difficulty opening jars or gripping items
- Visible loss of bulk, or wasting, of the muscles in the hand
- Clawing of the little and ring fingers, where the fingers are held slightly flexed
Figure 1: Wasting of the small muscles in the hand.
When are symptoms worse?
Symptoms are often worse when the elbow is bent, such as when using the telephone, driving a car or when in bed.
Some patients wake with numbness and tingling in the little and ring fingers during the night or first thing in the morning.
In the early stages, symptoms may be intermittent. In more advanced cases, the fingers may become permanently numb with little feeling.
Why early assessment is important
In more advanced cubital tunnel syndrome, weakness and muscle wasting may develop in the hand. Muscle wasting is often irreversible and it is best to treat the condition before it becomes this severe.
How is cubital tunnel syndrome diagnosed?
In most cases, your doctor will make the diagnosis after listening to your symptoms and examining your hand, wrist, elbow and nerve function.
It may be necessary to arrange further investigation with nerve conduction studies. These are electrical tests which help identify the site of nerve compression.
Occasionally, compression of nerves in the neck or shoulder can mimic the symptoms of cubital tunnel syndrome. Nerve conduction studies will usually help distinguish between these conditions.
Find out what to expect at your outpatient appointment.
Treatment for cubital tunnel syndrome
Treatment depends on the severity of symptoms, how long they have been present and whether there is any evidence of permanent nerve change.
Non-surgical treatment
Non-surgical treatment relies on understanding that the ulnar nerve lies in a tunnel behind the elbow joint. As the elbow bends, the nerve becomes stretched. If the nerve is compressed in the cubital tunnel, elbow flexion may trigger symptoms.
Nerve protection
Patients are usually advised to keep the elbow straight as often as possible and to avoid prolonged elbow flexion or leaning on the elbow.
Using the telephone with the unaffected hand or using a hands-free device can be helpful.
Night-time elbow splint
A soft night-time elbow splint can help control night-time symptoms and may be useful in some patients.
Surgical treatment
Surgery may be recommended for patients whose symptoms do not respond to non-surgical treatment.
Surgery involves releasing the ulnar nerve from the tight cubital tunnel behind the inside of the elbow.
There is debate amongst surgeons about whether anything further should be done to the nerve, such as moving it to the front of the elbow. This is called anterior transposition.
If the nerve is transposed, it can be left in the fatty tissue beneath the skin, called subcutaneous anterior transposition, or moved beneath the larger muscle mass, called submuscular anterior transposition.
Mr Farnell’s preference is to perform a simple in-situ ulnar nerve release and only transpose the nerve anteriorly if it is unstable afterwards.
Other surgical treatments have also been described, including excision of the medial epicondyle of the humerus. Mr Farnell will discuss which procedure is most suitable for you.
What happens during cubital tunnel surgery?
Surgery can usually be performed as a day case procedure using either general or regional anaesthesia. With regional anaesthesia, the arm is temporarily numb and paralysed for several hours.
After surgery, there will usually be a bulky bandage around the elbow. The stitches remain in place for approximately two weeks.
Read more about post-operative care.
Results of surgery
The outcome of surgery depends on several factors, including the severity of the cubital tunnel syndrome before treatment.
Sensory symptoms such as tingling and pins and needles may improve after surgery. However, muscle wasting is often irreversible and may not recover fully if the condition was severe before surgery.
Concerned about tingling in your little and ring fingers?
If you have numbness, pins and needles, night-time symptoms or hand weakness affecting the little and ring fingers, Mr Robert Farnell can assess whether cubital tunnel syndrome may be the cause.
Cubital tunnel syndrome FAQs
What is cubital tunnel syndrome?
Cubital tunnel syndrome is compression of the ulnar nerve as it passes through the cubital tunnel behind the elbow.
What are the symptoms of cubital tunnel syndrome?
Symptoms may include numbness, pins and needles or tingling in the little and ring fingers, pain radiating up the forearm, hand weakness and difficulty gripping objects.
Which fingers are affected by cubital tunnel syndrome?
Cubital tunnel syndrome usually affects the little finger and ring finger because these areas are supplied by the ulnar nerve.
Why are symptoms worse when the elbow is bent?
The ulnar nerve passes behind the elbow. When the elbow is bent, the nerve becomes stretched and symptoms may be triggered if the nerve is compressed.
Can cubital tunnel syndrome cause hand weakness?
Yes. Cubital tunnel syndrome can affect the small muscles in the hand, causing weakness, difficulty gripping and sometimes visible muscle wasting.
How is cubital tunnel syndrome diagnosed?
Diagnosis is usually based on symptoms and clinical examination. Nerve conduction studies may be recommended to confirm the site of nerve compression.
Can cubital tunnel syndrome be treated without surgery?
Yes. Non-surgical treatment may include avoiding prolonged elbow flexion, avoiding pressure on the elbow and using a soft night-time elbow splint.
When is surgery considered for cubital tunnel syndrome?
Surgery may be considered if symptoms do not improve with non-surgical treatment or if there is significant weakness, numbness or muscle wasting.
What is cubital tunnel release surgery?
Cubital tunnel release is an operation to release pressure on the ulnar nerve behind the inside of the elbow.
Can muscle wasting recover after cubital tunnel syndrome?
Muscle wasting is often irreversible and may not recover fully. This is why early assessment is important if symptoms are worsening or hand weakness is present.