Wrong-Way Wrist Bones.

Abstract

Humans are very manual creatures, which means that the 8 small and complexly connected wrist bones have a lot of responsibility. Their ability to function properly supports everything from activities of daily living and work to the creation of art and music. The wrist is frequently penalized by our reflexive, outstretched-arm attempts to ward off injuries during a fall or before an imminent collision. Wrist dislocations often occur without concomitant fractures, but the diverse patterns of carpal dislocation arise from the varying directions and amplitudes of the deforming forces. All of the wrist dislocations explored in this month’s “Case Connections” article required open reduction and some form of fixation. Considering the high degree of anatomical derangement and instability in these cases, the outcomes were remarkably good, thanks to carefully planned and executed orthopaedic interventions. In the July 27, 2016, edition of JBJS Case Connector, Phan et al. describe the case of a 47-year-old male bicyclist who was hit by a car and sustained complete scaphoid and lunate dislocations, as seen on initial radiographs (Fig. 1). The neurovascular exam was normal, but a second set of radiographs revealed further proximal migration of the lunate, suggesting loss of soft-tissue attachments. Fig. 1 Anteroposterior radiograph showing radial dislocation of the scaphoid and proximal migration of the lunate. Intraoperatively, through a volar incision, surgeons found that the soft tissues of the first dorsal wrist compartment were completely avulsed off the radius. The lunate, stripped of all its soft tissue, was found lying in the Parona space. Surgeons removed the lunate from the surgical field and preserved it in saline solution while they explored further; they found that the scaphoid was dislocated volarly and proximally, with retention of only a small, unvascularized dorsal soft-tissue attachment. Through a dorsal incision, surgeons noted a rupture of the extensor …