Darrach’s procedure is a surgical technique primarily used to address distal radioulnar joint (DRUJ) disorders, particularly in cases of chronic pain, instability, or dysfunction of the wrist caused by conditions such as rheumatoid arthritis, trauma, or degenerative joint disease. This procedure involves the excision of the distal end of the ulna, which helps alleviate pain and restore function by removing the source of mechanical irritation.
The distal radioulnar joint is a pivot joint formed between the distal ends of the radius and ulna bones of the forearm. It plays a crucial role in forearm rotation, allowing pronation and supination movements. The stability of the DRUJ is maintained by the triangular fibrocartilage complex (TFCC), the joint capsule, and surrounding ligaments.
In conditions such as rheumatoid arthritis, trauma, or post-traumatic arthritis, the DRUJ can become painful and unstable due to cartilage destruction, ligamentous laxity, or bone deformity. This leads to limited wrist motion, pain during rotation, and decreased grip strength.
Darrach’s procedure is indicated in patients with:
It is generally reserved for low-demand patients or those with limited functional requirements, as the procedure can lead to some loss of stability and strength.
Darrach’s procedure involves the resection of the distal 1 to 2 cm of the ulna, including the ulnar head. The surgery is typically performed under regional or general anesthesia with the patient in a supine position and the arm on an arm table.
Incision and Exposure: A longitudinal or curved incision is made over the dorsal-ulnar aspect of the wrist, centered over the distal ulna. Care is taken to protect the dorsal sensory branches of the ulnar nerve.
Soft Tissue Dissection: The extensor retinaculum and the extensor carpi ulnaris (ECU) tendon sheath are identified and preserved if possible. The joint capsule is incised to expose the distal ulna.
Resection of the Distal Ulna: The distal 1 to 2 cm of the ulna, including the ulnar head, is excised using an oscillating saw or bone rongeurs. The cut surface is smoothed to prevent soft tissue irritation.
Soft Tissue Balancing: The surrounding soft tissues, including the TFCC remnants and capsule, are repaired or reconstructed to provide some stability to the ulnar stump.
Closure: The extensor retinaculum and ECU sheath are repaired, and the skin is closed in layers.
Immobilization: The wrist is immobilized in a splint or cast, typically in a neutral or slight supination position, for 2 to 4 weeks.
Postoperative management focuses on pain control, edema reduction, and gradual restoration of wrist and forearm motion.
Rehabilitation aims to restore functional pronation and supination while minimizing instability or pain.
Darrach’s procedure has been shown to provide significant pain relief and improved wrist function in appropriately selected patients. Most patients regain satisfactory range of motion and are able to perform daily activities without significant limitations.
However, some degree of weakness in grip strength and forearm rotation may persist. The procedure is less suitable for high-demand patients or those requiring heavy manual labor due to potential instability of the ulnar stump.
As with any surgical procedure, Darrach’s procedure carries risks, including:
Careful surgical technique and postoperative rehabilitation help minimize these risks.
Other surgical options for DRUJ pathology include:
The choice of procedure depends on patient factors, surgeon preference, and the underlying pathology.
Darrach’s procedure remains a valuable surgical option for managing distal radioulnar joint disorders, especially in patients with chronic pain and instability due to arthritis or trauma. By excising the distal ulna, the procedure alleviates mechanical irritation and improves wrist function. While it may not be suitable for all patients, particularly those with high functional demands, it offers a relatively straightforward solution with good pain relief and functional outcomes in selected cases.
If you are experiencing persistent wrist pain or instability, consult an orthopedic specialist to determine if Darrach’s procedure or another treatment option is appropriate for your condition.