Volar Angle Stable Plating for Distal Radius Fractures

The treatment of distal radius fractures has evolved substantially over recent years. Most authors still agree that anatomic reconstruction of both the radiocarpal and radioulnar joints is required to restore normal wrist kinematics and achieve optimal outcomes in both the short and long term.1–3 More controversial is the question of how to achieve anatomic reconstruction of the distal radius. Stable extra-articular fractures may be treated with manipulation and casting. Intra-articular, unstable, and irreducible fractures, especially in the younger patient, require more invasive treatment. The options for internal fixation have greatly increased over the past 10 years. Dorsal plating was popular for some time, but concerns lingered over the lack of recovery of wrist flexion, which is believed to result from a combination of an extensive dorsal exposure and capsulotomy, in addition to the spaceoccupying plate, which leads to thick scar formation and capsular contracture.1 Two prospective, randomized controlled trials, published in 2005, compared the results of predominantly dorsal internal fixation with percutaneous fixation and external fixation, including mini-open reduction if required.4,5 Kreder and colleagues4 found that when displaced intra-articular fractures can be treated by indirect reduction and percutaneous fixation, a more rapid return to function and a superior functional outcome will be obtained than by open reduction and internal fixation, provided that the intra-articular step and gap formation is minimized. Grewal and colleagues5 terminated enrollment half-way through their study, since the dorsal plating group showed significantly higher complication rates, as well as significantly higher pain levels, weaker grip, and longer surgical and tourniquet times. A meta-analysis of outcomes of external fixation versus plate osteosynthesis for unstable distal radius fractures was published later in the same year.6 The review included 917 patients in the external fixation group and 603 in the plating group, of which only 55 were treated with a volar fixed-angle device. The authors did not detect any significant differences in grip strength, range of motion, radiographic alignment, pain, or physician-rated outcomes. Patients had higher rates of infection, hardware failures, and neuritis with external fixation and higher rates of tendon complications and early hardware removal with internal fixation. The authors concluded that the literature offered no evidence to support the use of internal fixation over external fixation for these injuries.6 The disappointing results of open reduction and internal fixation have to be revisited in light of the development of volar fixed-angle plate technology and fragment-specific low-profile fixation techniques. Robert Medoff and colleagues7,8 described a specific fragmentation pattern of the distal radius and derived his fragment-specific approach from this. They described five main articular fragments and developed the TriMed Wrist Fixation System (TriMed, Inc, Valencia, California), fragment-specific fixation implants for these fragments. This system enables the surgeon to reliably stabilize fracture fragments through limited volar and dorsal approaches and to institute immediate mobilization in the majority of cases.9,10 The early experience in our department with this system showed a restoration of articular congruity to less than 2 mm in 20 of 21 patients with AO type C2 and C3 fractures, with no loss of reduction at a minimum 6-months’ follow-up. The mean range of motion was 50 degrees flexion, 63 degrees extension, and a pronation-supination arc of 149 degrees.10 Before the advent of locking technology, volar plating was mainly indicated for volar rim shearing fractures.11,12 New angle stable plate designs have expanded the indications for volar plating to include dorsally displaced unstable fractures. A variety of designs (DVR, �and Innovations�� volar subchondral support systems, Avanta�� and the LCP Distal Radius Plate, Synthes North America) were developed, and clinical results were presented.13–17 These confirmed the safety and efficacy of these devices. In a comparison with external fixation, the restoration of intra-articular congruity, radial length, and volar tilt was significantly improved with volar plating.15 Moreover, successful maintenance of reduction, with minor settling of the fracture in only 3 of 23 patients, was noted in an osteopenic patient population over 75 years.14 The subsequent development of variable-angle volar locking plates offers the potential to combine the advantages of volar plating with the deliberate placement of fixation screws and pegs to achieve some degree of fragment-specific fixation.