Thoracic and lumbar fractures associated with skiing and snowboarding injuries according to the AO Comprehensive Classification.

BACKGROUND: The incidence of spinal fractures varies from 1% to 17% in alpine skiing injuries. Distinctions have been made regarding the differences in the mechanisms of injury and fracture types between skiing and snowboarding. Although fracture patterns have been described, there have not been any detailed descriptions of the specific fracture types and subgroups. PURPOSE: To address the patterns of spinal fractures associated with these sports and to determine the incidence of various fracture groups and subgroups as well as to determine whether the fracture patterns differ between skiing and snowboarding injuries. STUDY DESIGN: Descriptive epidemiology study. METHODS: This is a retrospective review of thoracic and lumbar spinal fractures associated with either skiing or snowboarding over a period of 5 years. The injuries were classified according to the AO Comprehensive Classification. In addition, isolated transverse process fractures and isolated spinous process fractures were included. Cervical spine fractures were excluded from this study. RESULTS: There were a total of 119 patients with thoracic and lumbar fractures that were identified after 1,283,348 skiing/snowboarding days. There were a total of 146 fractures, of which 114 were classified according to the AO Comprehensive Classification, with the remaining fractures (n = 32) consisting of isolated transverse or spinous process fractures. The preponderance of these injuries (94.7%) was compression injuries. Burst fractures (A3.1 and A3.2) made up 23%, and simple compression fractures (A1.1, A1.2, and A1.3) made up 71% of the total. Distraction injuries composed only 4.4%, and rotation injuries composed 0.9% of the total. The snowboarders incurred only compression fractures, whereas the 5 distraction injuries and the 1 rotational injury were noted only in the skier population. There were no patients with neurological deficits in this review. Fourteen skiers (14%) and 10 snowboarders (8%) were found to have isolated transverse process fractures. All 6 isolated spinous process fractures (4% of all fractures) were in the thoracic spine. CONCLUSION: Thoracic and lumbar fractures caused by skiing and snowboarding are mainly stable injuries, composed of either compression fractures, mostly simple compression injuries, or isolated transverse and spinous process fractures. Neurological injury was not seen in this study.

Biomechanical evaluation of locked plating in proximal humeral fractures.

The ideal method of fixation in proximal humeral fractures is not well established. Locked plating is a potential solution, but to date, there has been little support shown in the literature. We compared the biomechanical performance of a locked plate with that of an intramedullary humeral nail in a cadaveric model. Paired fresh-frozen cadaveric humeri (N = 5) were instrumented with either a locked plate or an intramedullary nail after creation of a 3-part osteotomy. Construct stiffness, cyclic loading behavior, and load to failure were evaluated. The locked plate was more stiff in valgus loading than the nail (P = .003). All other loading vectors showed no statistical differences in stiffness between the two constructs. The load to failure was 828 N for the plate and 901 N for the nail. The nail showed interfragmentary motion (degrees), or toggle, at zero load, whereas the plate did not. The locked plate, being stable at zero load, may prove useful in earlier pain-free rehabilitation of proximal humeral fractures.