Common peripheral nerve entrapments in the upper limb.

Entrapment of peripheral nerves can occur as they travel through restrictive spaces. This nerve compression can result in a constellation of signs and symptoms, which are often called syndromes. Patients initially report pain, paraesthesia and numbness, followed by weakness and clumsiness and, ultimately, muscle wasting. The specific region of paraesthesia and pain and the specific muscle weakness is determined by the peripheral nerve involved and the location of the entrapment. Diagnosis is mainly based on history and examination. Further investigations are available for atypical presentations. Each syndrome has its own set of risk factors, but repetitive action and muscle overuse are commonly associated with most syndromes. The treatment is activity modification followed by steroid injection and finally surgical decompression for ongoing persistent symptoms or severe initial presentation. This article outlines the history, examination, possible investigations and management for common peripheral nerve entrapments of the median, ulnar and radial nerves.