A clinical impression of avascular changes in the hook of the hamate a
fter fracture led to this study of the pattern and size of the hamate
hook vascular foramina. Its appears that vessels enter the hamate hook
at primarily two sites. The radial base foramina are large and always
present, while the ulnar tip foramina are small and absent in 29% of
specimens. In these hamates, fracture at the hook base could potential
ly compromise blood supply to the hook fragment, and this may be a fac
tor in hamate hook nonunion.