Cyclists risk permanent nerve damage from bumpy roads, study finds

Bike riding on cobbled, poorly maintained or potholed streets could give a cyclist permanent nerve damage, that’s the conclusion of a new study from researchers at Edinburgh Napier University in Scotland who found that riding for as little as 16 minutes on rough surfaces can produce what’s known as Hand Arm Vibration Syndrome (HAVS).

Your daily bike commute may not involve cobbled streets to rattle over like those in Edinburgh but the potholes and broken pavement common to Canadian cities where winter plays havoc on asphalt surfaces can be just as troublesome.

Every year, especially in the late spring before road crews get a chance to fix up the roads, potholes and broken pavement are a health risk to cyclists — and it’s not just from accidents and falls, says Dr. Mark Taylor from Edinburgh Napier, co-author of the new study which looks at vibrations to the arms and upper body caused by bad roads.

Bumpy roads can cause cyclist nerve damage after continued exposure…

“The minute you get onto a poorly maintained surface you’re getting a substantial duration of vibration exposure that’s being transferred up through your arms and into your shoulders,” says Dr. Taylor, to the Scotsman. “Continued exposure to such vibration levels over commuter journeys may lead to discomfort and potentially cause harm.”

A condition more typically associated with using hand-held vibrating tools like grinders and jackhammers, HAVS involves not just vascular issues but neurologic and musculoskeletal aspects, as well. The issue first gained medical attention back in 1918 when limestone quarry workers were attended to who reported numbness and discolouration of their fingers. Other symptoms include pain, tingling in the fingers and a loss of grip due to nerve damage. In severe cases, permanent nerve damage and even gangrene can result.

To help shine light on the problem, Taylor and his colleagues devised a vibration “data bike” with which to create a cycling vibration route map around their city in order to give cyclists the opportunity to avoid the bumpiest stretches and to alert the municipality of the problem.

“Cyclists should avoid road surfaces that may expose them to Havs,” says Professor Chris Oliver, co-author of the study from Edinburgh Napier. “The damage from HAVS can’t be reversed but reducing vibration exposure can help reduce the symptoms.”

Along with avoiding the worst roads in your city, there are ways to improve your bicycle’s capability to absorb the vibrations. According to the journal road.cc, riders should consider changing to wider tires for better shock absorption, changing a few components such as the seatpost, saddle and handlebars and putting on good quality bar tape.

In Canada, HAVS is a too-seldom diagnosed problem, according to University of Toronto professors Shixin Shen and Ronald House, who argue in a recent study that only two of 13 provinces and territories (BC and New Brunswick) have legislation that limits occupational exposure to hand-arm vibration. Thus, a lot of the burden goes to the family physicians to correctly identify the problem when it presents. “Hand-arm vibration syndrome is substantially underrecognized in Canada,” say the researchers. “A lack of appropriate and timely diagnosis and referral by primary care physicians appears to be an important reason for treatment delay.”

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