Dr Shawn M. Carney
Risks for Carpal Tunnel Syndrome: Trimming cannabis leaves and fungal infections?
Updated: Oct 26, 2022
CDC has reported on surprising causes of carpal tunnel syndrome, including the highly repetitive motion of cutting cannabis, which could conceivably give marijuana farmers a pinched nerve ... you can't make this stuff up!
If you were looking for two obscure risk factors for Carpal tunnel syndrome (CTS), you found them!
The CDC Wants You to Know that Trimming Cannabis Leaves May Cause CTS
In 2015, the United Food and Commercial Workers International Union put out a request to the National Institute for Occupational Safety and Health (NIOSH), which is part of the CDC, to evaluate working conditions of marijuana farmers.(1) A team of evaluators visited a 5-acre, pesticide-free farm in Washington state, which had already legalized cannabis for medicinal use in 1998 and recreational use in 2012. This farm employed three workers at the time. Digital force gauges and pinch gauges were used to assess manual hand forces during destemming, and a 'CyberGlove' electrogoniometer glove was used to assess dynamics and repetitive motion of the hand and fingers in trimming.
After interviewing and examining the employees as well as the farmer, the evaluation team concluded that the grip used by some of the staff as they trim buds may lead to CTS. This was not as much related to the force used on the scissors, as much as it was to being “highly repetitive work.” And though none of the employees actually had hand, wrist, or shoulder symptoms or other musculoskeletal problems at the time of the assessments, they were concerned about the longterm affects this set of activities may result in.
Paracoccidioidomycosis: It's Not Just a Lung and Skin Disease
Paracoccidioidomycosis is a systemic fungal infection caused by Paracoccidioides brasiliensis and is endemic to rural areas of Latin America. It is most commonly associated with symptoms affecting multiple organ systems, including pulmonary, skin, neurologic and musculoskeletal symptoms. But of these CTS is a very rare symptom.
In 2012 a case report was published which documented a 63-year-old white male agricultural worker from São Paulo, Brazil, who reported insidious and progressive pain, numbness, and tingling in his right hand and fingers, which began in April 2009.(2) Several prescription medications were tried but progressively the pain in the right hand increased. He even received administrations of methyl-prednisolone and lidocaine into his affected carpal tunnel area in September and October 2010, with poor response.
"After that, physical examination showed mild edema and warmth of the flexor surface of the hand and reduced wrist motion. Phalen test and Tinel signs were positive. In February 2011, an outpatient electrophysiologic evaluation showed a severe right focal demyelination of the median nerve at the wrist and mild acute denervation in the abductor pollicis brevis muscle, consistent with CTS".(2)
Figure. . A) Edema and erythema of the flexor surface of the hand of patient with paracoccidioidomycosis, carpal tunnel syndrome, and flexor tenosynovitis, Brazil. Note a fistulouspustulous nodule in the right thumb and forearm (arrows) and flexor contracture of the fourth finger. B) Flexor surface of the h and and forearm after surgery. C)Paracoccidioidesbrasiliensis
was directly identified on the thumb secretion, sputum, and flexor tenosynovectomy specimen by using a 10% potassium hydroxide preparation. This image was obtained from the thumb secretion. Note the characteristic multiple-budding yeast cells (pilot's wheel) with the well-defined refringent double wall. (2)
Eventually the patient was placed on antifungal and immunosuppressive treatments, and after an additional five months, nearly all symptoms had resolved.
Victory KR, Couch J, Lowe B, Green BJ. Notes from the Field: Occupational Hazards Associated with Harvesting and Processing Cannabis — Washington, 2015–2016. MMWR Morb Mortal Wkly Rep 2018;67:259–260. DOI: http://dx.doi.org/10.15585/mmwr.mm6708a7external icon.
von Glehn F, Damasceno A, Miotto N, Naseri EP, Costallat L, França MC, et al. Carpal Tunnel Syndrome with Paracoccidioidomycosis. Emerg Infect Dis. 2012;18(8):1390-1392. https://doi.org/10.3201/eid1808.120153.
The content and any recommendations in this article are for informational purposes only. They are not intended to replace the advice of the reader's own licensed healthcare professional or physician and are not intended to be taken as direct diagnostic or treatment directives. Any treatments described in this article may have known and unknown side effects and/or health hazards. Each reader is solely responsible for his or her own healthcare choices and decisions. The author advises the reader to discuss these ideas with a licensed naturopathic physician.