Ultrasound-guided Release of the Median Nerve at the Elbow in Patients With Lacertus Syndrome

The lacertus fibrosus is a thick, tough, fibrous band of connective tissue. The lacertus fibrosus is a continuation of the tendon of the biceps brachii muscle. It plays a role in protecting the median nerve, which passes under this ligament as it travels towards the hand.

Lacertus syndrome is an orthopaedic condition that occurs when the median nerve is compressed where it passes under the lacertus fibrosus. This syndrome can affect both men and women, generally after the age of 35. It can occur on one side or bilaterally. Common symptoms vary from person to person and include pain in the forearm, elbow and sometimes the shoulder, a feeling of tiredness or heaviness in the forearm, muscle weakness in the thumb and grip, clumsiness, loss of stamina and variable tingling in the first three fingers of the hand (thumb, index and middle fingers), similar to carpal tunnel syndrome.

Treatment for lacertus syndrome is generally aimed at relieving compression of the median nerve and reducing associated symptoms. Treatment options vary according to the severity of the condition and the patient's individual needs. They may include physiotherapy, non-steroidal anti-inflammatory drugs (NSAIDs), orthoses, corticosteroid injections and surgery.

Sectioning the Lacertus fibrosus frees the median nerve. It is performed as an outpatient procedure under local anaesthetic, and the patient can resume his or her activities immediately. Lacertus fibrosus section has been described as an open procedure, i.e. with a horizontal scar in the elbow crease.

Ultrasound guided surgery is an innovative technique that has proved its effectiveness for nerve releases such as the median nerve in the carpal tunnel or the ulnar nerve in the elbow. This new ultrasound-guided surgical technique reduces the side-effects associated with surgery (infection, algodystrophy, scarring), limits the need for time off work and reduces overall costs.

This new ultrasound-guided surgical technique was tested on a series of 18 cadavers and then on a series of 15 patients for whom a lacertus syndrome had been diagnosed. The patients underwent the operation without any immediate surgical or anaesthetic complications. Muscle strength returned immediately and persisted. Pain was reduced and all patients who were working were able to carry out their professional activities from the very first week. The millimetric skin incision healed without hypertrophic scar tissue. A small haematoma appeared at week 1 and resolved spontaneously. No other late complications were observed.

In this context, this study would consolidate the preliminary results observed and confirm the hypothesis that minimally invasive percutaneous surgery under ultrasound is appropriate for sectioning Lacertus fibrosus safely, rapidly and effectively in Lacertus syndrome.

Inclusion criteria

• Patient, male or female, aged ≥ 18 years and < 70 years
• Patient with isolated or bilateral Lacertus syndrome (no associated procedure on the day of surgery).
• Patient with a normal EMG

Exclusion criteria

• Patient with previous elbow surgery
• Patient with a history of elbow fracture
• Patient taking part in another study