[Cubital tunnel syndrome : Diagnostics and therapy]

[Nerve compression syndromes of the median and radial nerves at the elbow]

Nerve compression syndromes of the median and radial nerves at the elbow are usually caused by a combination of traction and pressure and are mainly characterized by loss of strength and dull, localized elbow pain. Muscular functional impairments can occur, whereas sensory impairments are less common. The diagnostics including a detailed medical history, neurological examination with, for example, lateral comparison muscle testing and imaging procedures such as X‑ray, sonography or magnetic resonance imaging (MRI) are essential. In the early stages, conservative treatment with immobilization and infiltrative cortisone treatment can be successful. If symptoms persist or progress, surgical interventions using magnifying glasses (from 2.5×) and microsurgical instruments or a microscope are indicated. It is particularly important to protect the vascular supply and the nerve gliding tissue in order to ensure optimal regeneration and thus function. With timely diagnostics and treatment the prognosis is good.

[Revision surgery for carpal and cubital tunnel syndrome]

BACKGROUND

Carpal tunnel syndrome, a compressive neuropathy of the median nerve at the wrist and cubital tunnel syndrome, a compressive neuropathy of the ulnar nerve at the elbow, are the two most common peripheral nerve compression syndromes. Chronic compressive neuropathy of peripheral nerves causes pain, paraesthesia and paresis. Treatment strategies include conservative options, but only surgical decompression can resolve the mechanical entrapment of the nerve with proven good clinical results. However, revision rates for persistent or recurrent carpal tunnel syndrome is estimated at around 5% and for refractory cubital tunnel syndrome at around 19%. Common causes for failure include incomplete release of the entrapment and postoperative perineural scarring.

THERAPY

Precise diagnostic work-up is obligatory before revision surgery. The strategy of revision surgery is first complete decompression of the affected nerve and then providing a healthy, vascularized perineural environment to allow nerve gliding and nerve healing and to avoid recurrent scarring. Various surgical options may be considered in revision surgery, including neurolysis, nerve wrapping and nerve repair. In addition, flaps may provide a well vascularized nerve coverage in the case of recurrent carpal tunnel syndrome. In the case of recurrent cubital tunnel syndrome, anterior transposition of the ulnar nerve is mostly performed for this purpose.

RESULTS

In general, revision surgery leads to improvement of symptoms, although the outcome of revision surgery is less favourable than after primary surgery and complete resolution of symptoms is unlikely.