Quick answer
Ulnar nerve entrapment is the second commonest nerve entrapment after carpal tunnel syndrome, usually behind the elbow (cubital tunnel) and sometimes in Guyon’s canal at the wrist. Its hallmark is numbness of the little finger and half the ring finger, worse with the elbow bent, followed by clumsiness and weak grip. Treatment starts with avoiding prolonged elbow bending and a night splint; nerve release surgery is needed for weakness, wasting or failed treatment.
✅ Last medically reviewed by Prof. Dr. Ibrahim Shaarawi, Professor of Orthopaedic Surgery, on 5 October 2026
The “funny bone” you feel when you knock your elbow is the ulnar nerve. When it is compressed constantly, little-finger numbness begins and, if neglected, can end in weak hand muscles. Here are the sites, symptoms and treatment, as part of our guide to carpal tunnel release and hand nerve surgery.
Where is the ulnar nerve trapped?
- Cubital tunnel (behind the elbow): the commonest site; pressure rises with prolonged elbow bending or leaning on the elbow.
- Guyon’s canal (little-finger side of the wrist): less common; seen in cyclists, with ganglion cysts and hamate fractures.
Symptoms
- Numbness and tingling in the little finger and half the ring finger.
- Worse with the elbow bent: holding a phone, sleeping with bent elbows.
- Pain behind the elbow at times.
- Clumsiness: difficulty opening jars, buttoning and writing.
- Advanced cases: wasting between thumb and index finger and clawing of the last two fingers.
Video: things slipping from your hand
Cubital tunnel or Guyon’s canal?
| Cubital tunnel (elbow) | Guyon’s canal (wrist) | |
|---|---|---|
| Numbness on the back of the hand (little-finger side) | Usually present | Usually absent |
| Worse with | Elbow bending | Pressure on the heel of the hand (cycling, crutches) |
| Common causes | Prolonged elbow bending, leaning, old fractures | Ganglion, hamate fracture, cycling |
| Surgery | Release at the elbow, sometimes transposition | Canal release and removing the cause |
Diagnosis
- Examination: Tinel’s sign behind the elbow, elbow flexion test, Froment’s sign for weak thumb adduction.
- Nerve conduction studies to locate and grade the entrapment.
- Elbow X-ray with old fractures or arthritis; ultrasound or MRI if a cyst is suspected.
Cervical disc disease can mimic it and must be excluded — see hand numbness: causes and treatment.
Key numbers to know
- Ulnar nerve entrapment at the elbow is the second most common entrapment neuropathy after carpal tunnel syndrome (Cochrane review, 2016).
- Across 9 randomised trials (587 patients), 69% improved after simple ulnar nerve decompression versus 75% after transposition — no significant difference — with more wound infections after transposition (Caliandro et al., Cochrane 2016).
- Carpal tunnel syndrome is the most common peripheral nerve entrapment worldwide (Padua et al., Lancet Neurology 2016).
| Treatment | When we use it | What to expect |
|---|---|---|
| Avoid prolonged elbow bending; night splint | Mild cases | Gradual improvement for many patients |
| Physiotherapy and nerve gliding | Mild and moderate cases | Less tingling and better movement |
| Simple (in situ) ulnar nerve decompression | Moderate to severe cases or hand muscle weakness | Results similar to transposition with fewer wound complications |
| Anterior transposition of the nerve | A nerve that slips out of its groove, or selected cases | Decided on what we find during surgery |
| Guyon’s canal release at the wrist | Compression at the wrist, such as a ganglion | Removes the cause and relieves little-finger tingling |
At Prof. Dr. Ibrahim Shaarawi’s clinics in Nasr City, Mohandeseen and New Cairo (5th Settlement) we examine the hand and review your nerve study at the same visit, confirming where and how badly the nerve is trapped before choosing a splint, injection or release.
Non-surgical treatment
- Avoid prolonged elbow bending; use a headset for calls.
- Don’t lean on the elbow.
- A night splint or a towel wrapped around the elbow to stop it bending during sleep.
- Nerve-gliding exercises.
Ulnar nerve release surgery
Surgery is indicated for weakness or wasting, moderate to severe entrapment on testing, or failed conservative treatment. Options are simple decompression in situ or anterior transposition in selected cases (such as a nerve that slips out of its groove). A Cochrane review found similar outcomes, with fewer wound complications after simple decompression. Nerve release costs 35,000–50,000 EGP.
Frequently asked questions about ulnar nerve entrapment
What causes little finger numbness?
Usually ulnar nerve entrapment at the elbow, especially with prolonged elbow bending, and sometimes in Guyon’s canal at the wrist or from the neck.
Is ulnar nerve entrapment serious?
It is not life-threatening, but neglect can lead to permanent weakness and wasting of the hand muscles, so early treatment matters.
Can ulnar nerve entrapment be treated without surgery?
Yes in mild cases: avoiding elbow bending, a night splint and nerve-gliding exercises. Surgery is for weakness, wasting or failed treatment.
What is cubital tunnel release?
Surgery that widens the tunnel behind the elbow through which the ulnar nerve runs, sometimes moving the nerve in front of the elbow; usually a day case.
What is the difference between cubital tunnel and Guyon’s canal syndrome?
Cubital tunnel is at the elbow and worse with bending; Guyon’s canal is at the wrist and worse with pressure on the heel of the hand, usually sparing sensation on the back of the hand.
To have your hand assessed and your nerve tests reviewed, book a consultation, call +20 155 240 4488 or message us on WhatsApp at +20 155 554 7181.
Medically reviewed by Prof. Dr. Ibrahim Shaarawi, Professor of Orthopaedic Surgery. This article is general medical education and does not replace an examination or the treatment plan your surgeon sets for you. See our medical disclaimer.
Related hand nerve and tendon guides
Related guides on nerve entrapment:
- Carpal tunnel release and hand nerve surgery
- Hand numbness: causes and treatment
- Hand numbness at night
- Left and right hand numbness
- Carpal tunnel syndrome
- Nerve entrapment
- Ganglion cyst of the hand and wrist
References
- Palmer BA, Hughes TB. Cubital tunnel syndrome. J Hand Surg Am. 2010;35(1):153-63.
- Chen SH, Tsai TM. Ulnar tunnel syndrome. J Hand Surg Am. 2014;39(3):571-9.
- Caliandro P, et al. Treatment for ulnar neuropathy at the elbow. Cochrane Database Syst Rev. 2016;11(11):CD006839.
- Schmid AB, et al. Entrapment neuropathies: a contemporary approach to pathophysiology, clinical assessment, and management. Pain Rep. 2020;5(4):e829.