Good News in Carpal Tunnel Syndrome Research

I complained in my book about the lack of research on carpal tunnel syndrome and other repetitive strain injuries (RSIs), but a recent book proves me wrong. Pathology and Intervention in Musculoskeletal Rehabilitation, 2nd Edition presents an overview of recent studies. There is a growing body of work that allows scientists to at least understand some of the mechanisms behind RSIs. The following information comes from the chapter Repetitive Stress Pathology: Soft Tissue by Nancy N. Byl, Mary F. Barbe, and Jane Fedorzyck.

Thankfully, researchers now acknowledge there is a complex set of multifactorial causes involved. The authors specifically state that any clinical assessment must take into consideration “the interactions of physical impairments, personal psychological factors, and psychosocial factors”. They unequivocally state that the most successful approach to treating RSIs takes a holistic approach. This is great news for patients who are stilling getting the run around from primary care physicians unfamiliar with the syndrome.

P. Michel Leahy's equation for cumulative, repetitive, forceful exposure is now augmented with genetics, personality, and coping mechanisms. This change in approach comes from the fact that while a clear correlation between hours on the computer and RSIs remains controversial, enough studies have demonstrated that high work stress, low job security and contentious relationships with supervisors are not.

Women, we have long known, are definitively more susceptible, but now motherhood, increased age and body mass have been added to the list.  As well as previous hand or wrist pain, so watch out, RSIs are permanent conditions.

Much of the progress though in understanding RSIs has been made in studying the pathophysiological mechanisms behind them. Researchers are now working off a conceptual model where tissues are disrupted, triggering inflammation and interrupting the wound healing process. Chronic inflammation begins at the wound site, but then becomes centralized inflammation as it spreads well past the original damaged tissue. The tissues themselves then change by thickening, disorganizing and even dying, and this process can spread well beyond the original injury site.

Studies confirm motor behavior changes can also come into play as a result of these tissue changes. First nerve damage, then sensory loss and finally, a systemic response where tissues become more sensitive and patients engage in something called ‘sickness behavior’ which deserves (and will get) it's own post. They call this peripheralization, where the disorder worsens, traveling away from the original wound site.

I’ve long thought RSI was a disease, not a disorder; but it seems the scientists know more than I do—studies show the soft tissue system indeed becomes disordered at the cellular level. If you’re having trouble convincing your doctor, your boss or your family the seriousness of your RSI, you might want to recommend this book to them.

@JillGambaro is the author of The Truth About Carpal Tunnel Syndrome . She has lived with multiple repetitive strain injuries known as a “double crush” for over 15 years. A former board member of the Los Angeles Repetitive Strain Injury Support Group and the Cumulative Trauma Disorders Resource Network, Jill advocates for prevention, patient engagement and healthy playing for musicians through her Blog, Facebook and Twitter @IckyFingersMovi. Look for her upcoming documentary Icky Fingers.