Malunions of the Distal Radius

Fractures of the distal radius are common injuries, comprising approximately 8% to 17% of fractures seen in the emergency department. These injuries largely occur in 2 distinct populations: a smaller subset composed of high-energy fractures, which are often seen in young adults, and a larger group of low-energy fragility fractures, which are more frequently noted in older adults. The overall incidence of the injury is expected to increase over the next 20 years, paralleling the aging of the US population as a whole. Treatment paradigms for distal radius fractures have evolved significantly as the biomechanics of the wrist have been elucidated. Although initial descriptions classified distal radius fractures as a largely homogenous group of injuries that healed well with minimal treatment, it is now recognized that these injuries display significant variation in fracture pattern and stability, with certain fracture deformities leading to poor prognosis if left uncorrected. Considerable effort has been expended in investigating and determining appropriate treatments for different fracture types, taking into account patientspecific factors including functional demands and overall health. In spite of significant advances in developing treatment strategies, complication rates from improper or failed treatment regimens remain high, ranging from 23% to 31%. Malunion is the most common complication following distal radius fractures. This occurs in approximately 23% of nonsurgically treated injuries and approximately 11% of operatively treated fractures. Malunions may be extraarticular (involving the metaphyseal region) or intra-articular (manifesting with residual joint incongruity) and can present along a spectrum of severity, ranging from asymptomatic radiographic abnormalities to disabling deformities associated with significant pain and functional impairment. The incidence of clinically apparent malunions will likely increase in the future, reflecting both the overall increase in distal radius fractures and the increased functional demands of a longerliving adult population. Historically, treatment for clinically significant malunion has been operative, consisting primarily of corrective osteotomies with adjunct bone grafting and fixation. Recent research to define optimal treatment protocols for malunions has focused on: (1) determining the appropriate indications for intervention; (2) developing appropriate surgical techniques incorporating new insights into the biomechanics of wrist function; and (3) developing new technologies to improve the accuracy and efficacy of operative intervention. In this chapter we will attempt to provide a summary of the current literature regarding distal radius malunions while detailing some of the work that has gone into addressing the questions listed above.