**1. Introduction**

Entrapment neuropathy, impingement syndrome or compression neuropathy are clinical conditions that develop due to compression of peripheral nerves in various narrow spaces or tunnels along their anatomical course due to different reasons such as trauma, anomaly, tumor, metabolic disease [1–5]. "Entrapment", "Compression" or similar terms are used to indicate that the onset of the problem is not caused by the nerves, but that it develops secondary to external mechanical effects [6]. While some neuropathies are common, some are rare [3].

In general, these neuropathies are thought to occur in actively working young/ middle-aged individuals (between the ages of 25 and 40), especially in predisposing professions or having a history of certain medical conditions, and in individuals between the ages of 40 and 60 (due to hormonal factors) [3, 4]. In order to diagnose entrapment neuropathy, the patient's clinical history and examination are very important. However, it can sometimes be difficult to diagnose only by clinical history and examination. At this stage, it may be necessary to using imaging techniques. Electrophysiological studies (including electromyography and nerve conduction studies) are the gold standard in detecting the presence of lesions and determining the location of impingement neuropathies and nerve damage [7–9].

#### *Demyelination Disorders*

After the impingement, a series of symptoms such as pain, change or loss of sensation, motor dysfunction and muscle atrophy are usually observed. The severity of the problem is directly proportional to the duration of exposure to compression, its shape, severity and size [1, 10]. Pain and loss of strength are the most common symptoms of entrapment neuropathies. Medical conditions such as rheumatoid arthritis, diabetes, pregnancy, and acromegaly may cause entrapment neuropathy to present a more rapid and severe clinical picture [6].

In this study, the definitions of entrapment neuropathies observed in the upper limb, their impingement levels, causes and clinical conditions that may be seen due to impingement were reviewed.
