Session I - Upper Extremity

Nonunion following ORIF of Radial Head Fractures

David Ring, MD; Jesse B. Jupiter, MD, Massachusetts General Hospital, Boston, MA

Purpose: Open reduction and internal fixation (ORIF) of fractures of the radial head has become more commonplace as the result of both improvements in the techniques and implants for the fixation of small articular fractures as well as the increasing recognition of the important role that the radial head plays in the stability of the forearm and elbowparticularly in the face of acute combined osseous and ligamentous injury. The blood supply to the radial head is tenuous in analogy with that encountered at the femoral head. The elbow capsule attaches to the proximal radial metaphysis, limiting the number of vessels supplying the head. Intraarticular fracture has the potential to separate fragments >from their blood supply. The additional soft tissue dissection associated with open reduction and internal fixation may further disrupt the blood supply, thereby increasing the risk of delayed or nonunion and avascular necrosis. To date, reports of operative radial head fixation have made little mention of these complications.

Methods: Retrospective review of 73 patients undergoing ORIF of fractures of the radial head at 2 institutions over a 7 year period revealed 7 with nonunion. There were 5 males and 2 females with an average age of 35 years (range 17 to 61). All of the fractures were comminuted (Mason type 3). These 7 ununited fractures represented 13% (7 of 52) of all Mason type 3 fractures, and 25% (7 of 28) of fractures with complete separation of all articular fragments from the radial neck (subclassified type 3B). Four fractures were the result of high energy and 3 of moderate energy traumatic injuries. Two fractures represented part of a posterior Monteggia injury and three were associated with a posterior fracture-dislocation of the elbow. These fractures were all characterized by complex comminution ( OTA Type 21-C2). All but one required the use of a minifragment plate for fixation. Ancillary minifragment screws, Herbert screws, and Kirschner wires were required in every case. In one case autogenous cancellous bone graft had been applied at the fracture site during the initial operative fixation. Nonunion was diagnosed on the basis of persistence of the fracture line on radiographs at a minimum of 6 months after the injury. Hardware breakage or loosening occurred in five patientsall of whom had symptoms consisting of crepitance with forearm rotation and pain along the lateral elbow. All five of these symptomatic patients underwent radial head excision at an average of 11 months after the injury (range 6 to 16).

Results: The five patients treated with excision have been followed for an average of 33 months after the injury. None has complaints referable to instability or pain of the elbow or forearm. Forearm rotation averaged 130 degrees (range 100 to 160 degrees). The two patients who did not undergo radial head resection were functioning well without complaints at 16 and 18 months follow-up.

Conclusions/Significance: Open reduction and internal fixation of complex, comminuted fractures of the radial head may lead to nonunion in upwards of 13% of patients. The reconstructed radial head functioned well as a spacer until hardware breakage or loosening led to the development of pain and crepitance. Late resection appears to lead to good results without compromising the function the elbow or forearm.