Interobserver Variability of the Diagnosis of Scaphoid Proximal Pole Fractures.

Fractures of the proximal pole of the scaphoid are prone to adverse outcomes such as nonunion and avascular necrosis. Distinction of scaphoid proximal pole fractures from waist fractures is important for management but it is unclear if the distinction is reliable.  A consecutive series of 29 scaphoid fractures from one tertiary hospital was collected consisting of 5 scaphoid proximal pole and 24 scaphoid waist fractures. Fifty-seven members of the Science of Variation Group (SOVG) were randomized to diagnose fracture location and displacement by using radiographs alone or radiographs and a computed tomography (CT) scan.  Observers reviewing radiographs alone and observers reviewing radiographs and CT scans both had substantial agreement on fracture location (κ = 0.82 and κ = 0.80, respectively;  = 0.54). Both groups had only fair agreement on fracture displacement (κ = 0.28 and κ = 0.35, respectively;  = 0.029).  Proximal pole fractures are sufficiently distinct from proximal waist fractures that CT does not improve reliability of diagnosis.  Level IV interobserver reliability case-control study.