Ulnar nerve entrapment is classified by location of entrapment. The ulnar nerve passes through several small spaces as it courses through the medial side of the upper extremity, and at these points the nerve is vulnerable to compression or entrapment—a so-called "pinched nerve".
Ulnar nerve compression is categorized by its location of compression. The ulnar nerve traverses several narrow passageways as it runs along the medial aspect of the upper limb, and at these points the nerve is susceptible to pressure or entrapment—a so-called "pinched nerve".