CPT® Code 25240

The procedure described by CPT® Code 25240 involves the excision of the distal ulna, which can be either partial or complete. This surgical intervention is typically performed to address various conditions affecting the wrist, particularly those related to the distal ulna's anatomy and function. The term "Darrach type" refers to a specific method of excision that may be employed during the procedure, indicating a technique that focuses on the distal ulna's removal while preserving surrounding structures when feasible. The procedure begins with an incision made over the posterior aspect of the wrist, allowing access to the dorsal retinaculum, which is a fibrous band that stabilizes the extensor tendons. The surgical approach includes making transverse incisions at both the proximal and distal borders of the retinaculum, followed by a longitudinal incision through the sixth compartment, which houses the extensor carpi ulnaris tendon. Careful dissection is crucial to expose the distal ulna while protecting vital structures such as the ulnar artery and nerve. The excision itself involves removing the distal 1-2 cm of the ulna, with an emphasis on preserving the ulnar styloid process and the ulnar collateral ligament whenever possible. After the excision, the remaining bone is smoothed and contoured to ensure proper healing and function. Finally, the remnants of the wrist capsule are anchored to the distal ulna, and the incision is meticulously closed in layers to promote optimal recovery.