CPT® Code 25100

The procedure described by CPT® Code 25100 refers to an arthrotomy of the wrist joint that includes a biopsy. An arthrotomy is a surgical procedure that involves making an incision into a joint to gain access for examination or treatment. In this case, the incision is typically made longitudinally along the midline or horizontally in accordance with Langer's lines, which are natural skin creases that help minimize scarring. The incision is performed on the dorsal (back) aspect of the wrist, and the specific approach may vary depending on the location of the pathology being addressed. During the procedure, full-thickness skin flaps are developed down to the extensor retinaculum, a fibrous band that holds the tendons of the wrist in place. Care is taken to protect important anatomical structures, including the superficial radial nerve, the dorsal sensory branch of the ulnar nerve, and various blood vessels. The retinaculum is then incised longitudinally over the third dorsal compartment to facilitate access to the wrist joint. If the surgical team needs to access the ulnar side of the wrist, the extensor pollicis longus tendon is retracted radially, and the fourth extensor compartment may be elevated subperiosteally, or the septum between the third and fourth compartments may be divided to create a flap over the ulna. Conversely, if access to the radial side is required, the extensor retinaculum is elevated off Lister's tubercle, and the second dorsal compartment is released. The procedure may also involve capsulotomy, where the dorsal radioulnar ligament is incised for ulnar capsulotomy, or the dorsal radiocarpal and intercarpal ligaments are incised for radial capsulotomy, following the natural alignment of their fibers. Once the wrist capsule is incised, the wrist joint is exposed, allowing for the biopsy to be performed using biopsy forceps to obtain a tissue sample. This procedure is critical for diagnosing various conditions affecting the wrist joint. After the necessary tissue samples are collected, the joint is flushed with sterile saline, and the surgical wound is closed in layers to promote proper healing.