Someone lucky enough to still have grandparents around may have heard them predict the likelihood of rain, based on the pain in their joints. While this prognostication prowess has been largely attributed to the tales of old wives, medical research has suggested that there may be some accuracy in weather predictions that are based on joint pain.

It has to do with barometric pressure. This common meteorological term, which is also known as atmospheric pressure, is the force exerted by the atmosphere at a given point. It is, in fact, the weight of the air.

Weather experts note that fluctuations in barometric pressure are usually a sign of weather conditions changing. A rise in pressure usually means improving weather while falling pressure may reflect the impending inclement weather. Barometric pressures will also vary with altitude and moisture.

Osteoarthritis and Barometric Pressure

According to Dr. Kwame Ennina joint replacement surgeon in the North Texas area and a member of the referral line of Texas Health Spine & Orthopedic Center, "Osteoarthritis occurs when the protective cartilage on the ends of your bones wears down over time. While this painful condition can damage any joint in your body, it most commonly affects joints in your hands, knees, hips, and spine.

"Osteoarthritis can occur when the cartilage that cushions the ends of bones in joints gradually deteriorates. Cartilage is a firm, slippery tissue that permits nearly frictionless joint motion. Several factors can cause the slick surface of the cartilage to become rough, and if the cartilage wears down completely, you may be left with bone rubbing on bone."

Factors that can lead to osteoarthritis include:

• Gender – Women are more likely to have this condition than men.
• Older age – This risk increases with age.
• Obesity – Extra body weight contributes to osteoarthritis because it adds stress on the weight-bearing joints, such as knees and hips. Also, fat tissue produces proteins that may cause harmful inflammation in and around the joints.
• Joint injuries – injuries from playing sports, repetitive stress from work or from an accident may increase the risk of osteoarthritis.
• Genetics – Some people inherit a tendency to develop this condition.

"In addition to a loss of flexibility and tenderness around the joints, osteoarthritis can cause chronic pain," Dr. Ennin said. "Research has suggested that this pain occurs more often when the barometric pressure is decreasing."

New Studies on Stormy Weather

In a recently published report, Dr. Elaine Husni, director of Cleveland Clinic's Arthritis and Musculoskeletal Center noted, "There is some consensus that lower barometric pressure and dropping temperatures correlate with more joint pain. The thinking is that the lightness of the air can cause the thin lining known as the joint capsule, which surrounds the joints and maintains lubrication, to expand and stretch nerves, causing pain. A similar phenomenon can occur with humidity changes. The shift in pressure can cause swelling around the joints."

The Arthritis Foundation points to several other studies that support the effect of the weather on joint pain. It notes that if the results of the various studies are combined, "the general consensus is that cold, wet weather is the worst for inciting arthritis pain." The group also notes that changes in barometric pressure seem to be more important for pain levels than the actual barometric pressure. This means that either a cold front or warm front coming in can ramp up the ache in one's knee or hip, but once the weather has settled in, that pain will even out.

"While more research on this phenomenon is needed," said Dr. Ennin. "The anecdotal evidence is certainly voluminous."

"It is interesting to note that some studies point to changes in patient physical activity due to weather and how this affected their osteoarthritis. Pain was lower on days that were sunny and dry and greater on those that were cold and damp. On inclement days, most of us stay inside and are sedentary, and this lack of physical activity is a well-known cause of increased pain from osteoarthritis. Thus, one might ask if the cause of this pain is the barometric pressure, the lack of physical activity due to bad weather, or both?"

What to Do About Weather Related Joint Pain

A study tracked online searches for terms related to arthritis and knee and hip pain and weather changes over five years in 50 American cities. When the temperature fell below minus 5 degrees Celsius and 30 degrees Celsius, search volumes for hip pain increased by 12 index points and for knee pain increased by 18 points. When it was greater than 30 degrees, search volumes dropped by 7 index points.

While it would be great if everyone who has osteoarthritis could move to someplace warm and dry year around, this is not possible. It is, therefore necessary for these sufferers to take remedial actions in order to reduce the pain.

"I recommend osteoarthritis patients try to keep their core warm and dry during the fall, winter and early spring months," Dr. Ennin said. "We also suggest anti-inflammatory medications and regular physical activity, such as walking and losing excess weight. If the chronic pain persists, joint replacement should be considered."