Up to 30% of patients after distal radius fractures suffer from ulnar-sided wrist pain. 1 This is manifested in the form of wrist pain, restricted movement, weakness, and instability, even after correct reduction of the fracture and bony union. The integrity of the distal radioulnar joint (DRUJ) is necessary for stability and load transfer from the forearm to the wrist. [2][3][4] Osteoarthritis of the DRUJ may occur after trauma due to a bony deformity, a ligamentous injury, or combination of both. 1,5,16 In the surgical treatment of osteoarthritis, "salvage operations" are often necessary, in which the ulnar head is resected partially or completely. 7-10 Numerous clinical studies have demonstrated a reduction of painful clinical symptoms for all these techniques. 11-14 Biomechanically, even a partial resection of the distal ulna destabilizes the wrist, and clinically, it may lead to instability of the distal ulnar stump and the radius. 15,16 Distal radioulnar impingement occurs because the distal support of the radius for rotation and the "cam effect" of the distal ulna have been ablated. As a result, instability of the DRUJ may again lead to restriction of motion and strength as well as to increased pain. [17][18][19] To reduce DRUJ instability, various "soft tissue stabilization operations" have been developed. The most common techniques are the pronator quadratus-interposition flap (Johnson procedure) 20 and the extensor carpi ulnaris (ECU)-flexor carpi ulnaris (FCU) tenodesis (Breen-Jupiter tenodesis). [21][22][23] Biomechanical studies, however, show that these procedures do not provide adequate stabilization of the distal ulna. 24 Ulnar head prostheses have also been developed to restore the integrity of the DRUJ, which has been shown experimentally 6 and clinically. [25][26][27][28] Keywords ► distal radioulnar joint (DRUJ) ► osteoarthritis ► arthroplasty ► ulnar head resection ► ulnar head prosthesis
AbstractA stable distal radioulnar joint (DRUJ) is mandatory for the function and load transmission in the wrist and forearm. Resectional salvage procedures such as the Darrach procedure, Bowers arthroplasty, and Sauvé-Kapandji procedure include the potential risk of radioulnar instability and impingement, which can lead to pain and weakness. Soft tissue stabilizing techniques have only limited success rates in solving these problems. In an attempt to stabilize the distal forearm mechanically following ulnar head resection, various endoprostheses have been developed to replace the ulnar head. The prostheses can be used for secondary treatment of failed ulnar head resection, but they can also achieve good results in the primary treatment of osteoarthritis of the DRUJ. Our experience consists of twenty-five patients (follow-up 30 months) with DRUJ osteoarthritis who were treated with an ulnar head prosthesis, with improvement in pain, range of motion, and grip strength. An ulnar head prosthesis should be considered as a treatment option for a painful DRUJ.