Occupational medicine
-
Occupational medicine · Aug 2003
ReviewHypothenar hammer syndrome: a discrete syndrome to be distinguished from hand-arm vibration syndrome.
Hypothenar hammer syndrome (HHS) is a cause of vascular insufficiency to the hand and may be manifest as Raynaud's phenomenon. The cause is trauma to the vulnerable portion of the ulnar artery as it passes over the hamate bone, which may result in thrombosis, irregularity or aneurysm formation. ⋯ Colour and temperature changes occur more diffusely in HHS than in classical Raynaud's phenomenon and the absence of the triphasic colour change may alert clinicians to the diagnosis, which may be confirmed by Allen's test. Doppler or arteriographic studies are required for confirmation. It is important to recognize the possibility of HHS in the occupational setting as a potentially curable cause of Raynaud's phenomenon, distinct from hand-arm vibration syndrome. The possibility exists of HHS occurring as a result of repeated hypothenar trauma from vibrating tools, in which case the nature and magnitude of the individual episode of trauma may be more important than the weighted acceleration level of vibration exposure.