Health Alert: Recognizing Hypothenar Hammer Syndrome

Have you heard of Hypothenar Hammer Syndrome? It’s a rare condition, but those in the construction trades have or will probably run across it in their careers at some point. In April, we focused on safety in the construction industry and what steps workers can take to protect themselves on the job. Check out our Construction Connection video playlist on YouTube and subscribe to SCT’s YouTube Channel for more safety videos.

The Montreal-based Institut de recherche Robert-Sauvé en santé et en sécurité du travail (Robert-Sauvé Research Institute for Occupational Health and Safety) recently released an informational pamphlet about Hypothenar Hammer Syndrome, a disease that is caused by repetitive trauma to the hand.

What is Hypothenar Hammer Syndrome (HHS)?

HHS is an injury to the ulnar artery that reduces blood supply to the fingers, especially impacting the third, fourth, and fifth digits (the middle, ring, and pinky fingers). Considered a traumatic injury, HHS can occur when workers “repetitively use the heel of their hand as a hammer to pound and flatten or to press or twist objects,” according to the IRRST publication.

The ulnar artery delivers oxygenated blood to the hand. Symptoms of HHS include:

  • white or blue, stiff and painful fingers
  • hypersensitivity to cold
  • decrease in muscle strength in the hand
  • impression of a palpable mass in the palm
  • pins and needles feeling or numbness in the fingers

High Risk Individuals/Careers

IRRST indicated that the following professionals/industries are at the highest risk for developing HHS:

  • factory workers
  • machinists
  • metal workers
  • construction workers, miners
  • mechanics
  • forestry workers
  • gardeners
  • landscapers
  • farmers
  • students training in any of the above fields

Common tools used by/in the high risk individuals/careers include “electrical or pneumatic vibrating tools, brush cutters/trimmers, milling machines, grinding machines, jackhammers and saws, hammers, wrenches, pliers, scissors, and presses of every kind.” Continual use and/or overuse of these tools can also cause a potential for HHS.

Prevention is Key!

Though there is no cure for HHS, the IRRST pamphlet recommends the following tips to help prevent the syndrome:

  1. use work methods that avert acute or repetitive trauma
  2. switch tasks regularly/interval work, or rest your hands during the work day
  3. use properly maintained tools meant for the task at hand
  4. don’t use the palm of your hand as a hammer to strike a tool or object
  5. don’t use excessive force when gripping tools like wrenches, scissors, etc.