The Palpable Scaphoid Surface Area in Various Wrist Positions.

Abstract

To determine the theoretical amount of surface area available for palpation of the scaphoid in various wrist positions and to provide a guide depicting which wrist position will expose proximal pole, waist, and distal pole fractures. Using 3 fresh-frozen male cadaver wrists, we digitized palpable surface areas (dorsal, volar, and snuffbox) of the scaphoid in several wrist positions. The entire scaphoid was then excised and a digitized 3-dimensional reconstruction of the entire scaphoid was obtained. The 2 images were superimposed and the surface area was calculated The maximum palpable area of the scaphoid was achieved with the wrist in neutral extension and maximum ulnar deviation and the wrist in maximum flexion and neutral deviation. Neutral wrist extension and ulnar deviation exposed all but the most proximal portion of the proximal pole and the distal pole, which made this the ideal position to detect tenderness from a scaphoid waist fracture and larger proximal pole fractures. Maximum wrist flexion with neutral wrist deviation exposed the entire proximal pole, which made this the ideal position to detect tenderness from a proximal pole scaphoid fracture. Wrist position influences the amount of scaphoid surface area available for palpation and should be considered when examining a patient with a suspected scaphoid fracture. The scaphoid should be palpated in 3 anatomic regions with the wrist placed in different positions to maximally expose the anatomical region being palpated.