Several herbicide applicators have been diagnosed with ‘trigger thumb’ (Stenosing tenosynovitis) or ligament damage to the thumb possibly caused by excessive use, and/or stiff spring pressure with some handgun applicators. Trigger thumb involves the pulleys and tendons in the hand that bend the fingers/thumb. The condition can be relieved with a steroid injection at the base of the thumb, or surgery in more severe cases.
- Rod Cook, La Plata County Weed Supervisor: We hope to fix this problem by reducing the trigger spring pressure on the handgun.
- Ted Brown, Clear Creek Co Weed Supervisor: I had trigger thumb in 2011, but haven’t had any recurrences; however, I’ve reduced using the handguns but will consider reducing spring pressure on triggers.
- Tina Booton, Weld Co Weed Supervisor: We try to use the keeper as much as possible on the trigger to reduce stress on the thumb.
- Amy Sidener, Grand Co Weed Supervisor: I had damage to the CMC joint after 9 years of herbicide application with handguns. I have a "brace" that was built by an occupational therapist to assist with proper thumb positioning and have changed spray guns to something similar to the Hypro Hydra Gun--more ergonomic and the pressure on that joint is much less. Seems to help.
* Bones that make up the base joint of the thumb – a Carpal (wrist) bone and a Metacarpal or long bone of the thumb – the (CMC) joint is the most common place in the hand for arthritis.