Cubital tunnel syndrome / ulnar nerve entrapment

Cubital tunnel syndrome / ulnar nerve entrapment

The cubital tunnel syndrome, also called ulnar nerve entrapment, is caused by a compression of the ulnar nerve in the cubital tunnel, a canal proceeding through the elbow.

In case of the cubital syndrome, there is an excessive narrowing under the ulnar ligament of the ulnar nerve in the elbow and/or under the flexor carpi ulnaris muscles. Within this area, the ulnar nerve is located at the medial edge of the elbow between skin and bone, without any significant cushion by soft tissue. Even slightly bumping into this area can cause paresthesia. Due to its exposed location, the nerve is prone to injury and damage.

Symptoms cubital tunnel syndrome (ulnar nerve entrapment)

A typical symptom of the cubital tunnel syndrome is sensation disturbance or numbness of the little finger, the side of the ring finger showing to the little finger and the side of the hand next to the little finger. A longer ulnar nerve entrapment is to cause a loss of strength or paralyzation of the hand, for example, while writing, opening a bottle or a can and spreading of fingers. At a progressive state, a severe symptom of cubital tunnel syndrome is atrophy of the middle hand, best visible between thumb and index finger. Irradiating pain from the inner side of the elbow into the little finger is quite rare. Here are the symptoms of cubital tunnel syndrome in an overview:

  • sensation disturbance / numbness of little finger, the side showing to the little finger of the ring finger and the side of the hand next to the little finger
  • loss of strength or paralyzation of the hand
  • atrophy of the middle hand
  • rarely pain radiating from the inner side of the elbow into the little finger

Causes cubital tunnel syndrome (ulnar nerve entrapment)

Cubital tunnel syndrome can have several causes: elbow damage dated back several years, arthrosis of the elbow or chronic pressure damage of the nerve. The latter often originates from supporting elbows on a hard underground, for example, a desk, or from long lasting bending of elbows, for example, at night.

Diagnostics cubital tunnel syndrome (ulnar nerve entrapment)

The diagnosis cubital tunnel syndrome is confirmed by measuring the electrical conductivity of the nerves. A therapy in time can provide a permanent cure. But existing atrophy caused by cubital tunnel syndrome may not or not sufficiently decrease.

Therapy cubital tunnel syndrome (ulnar nerve entrapment)–cubital tunnel surgery

The cubital tunnel syndrome can be treated by microsurgery, a so-called cubital tunnel surgery. Drugs supporting the clotting of blood are to be stopped or substituted before cubital tunnel surgery, if necessary after consulting the family doctor. Patients must have an empty stomach (this comprises eating, drinking and smoking). After the operation, it is not possible to drive the car by oneself but to let another person drive you.

During the outpatient cubital tunnel surgery, regional anesthesia is applied plus optional sedation (‘twighlight sleep’). The first step of surgical exposure and relief of the entrapped ulnar nerve is a skin incision of 3-4 cm (1-1.5 inches) at the inner side of the elbow. A soft tissue over the nerve and, if necessary, a muscle (m. epitrochleoanconaeus) is cut through to remove the ulnar nerve compression. Under certain circumstances, the ulnar nerve is relocated at the front side of the elbow. A small drainage is placed into the wound at the end of cubital tunnel surgery.

Complications (general/special) cubital tunnel surgery

After the surgical solution of the cubital tunnel syndrome, small hematoma and swellings best decrease through aktive movement and loosening of bandages. A severe swelling necessitates additional ice pack treatments. But the wound has to be kept dry and must not get wet.
The inflammation or infection rate of patients undergoing cubital tunnel surgery is very low. In case of any sign of infection, for example, swelling, pounding pain in the surgical area, reddening or festering of the wound, a physician has to be consulted. The best would be a consultation at Beta Klinik.
Theoretically, a damage of the ulnar nerve is possible. Extremely rare is the emergence of a sympathetic reflex dystrophy, also called complex regional pain syndrome (CRPS).
Ulnar nerve recovery takes quite long because of the long recovery line from the elbow to the fingers. Thus, the decrease of sensation disturbance and loss of strength (paresis) can take a long time. In case cubital tunnel syndrome has caused atrophy, the improvement is often incomplete.
A new compression of the ulnar nerve (so-called recurrent cubital tunnel syndrome / ulnar nerve entrapment) is rare, especially when pressure to the elbow near at and around the operated area is avoided.

Aftercare cubital tunnel surgery

To avoid a swelling of the hand and to recover quickly, the hand has to be positioned at height of the upper body, and strains are to to be refrained from. A sling is not necessary. From first postoperative day, a careful movement of the elbow is necessary.
The fist change of bandages takes place on the first day as well as the removal of the drainage. Slowly, hand and arm can be increasingly strained. Stitches are removed after 7-10 days. Washing the arm and showering are possible at the following day. The arm needs 2-3 weeks of low strain to be used for normal daily activities and most occupational ones. To take care of the ulnar nerve, a strong bending of the elbow over a long period, for example, while supporting the arm on the desk or while sleeping, should be avoided from now on.


If unexpected symptoms after cubital tunnel surgery occur like severe pain, movement limitations of joints or a severe swelling, please consult Beta Klinik.