If you see this dog, please don’t approach her. & This Week’s 1-Page Health News

This is Liberty. Liberty is a puppy who is training to be a guide dog for the blind. One of our awesome patients, Karen B., is training and socializing Liberty for a year. If you’re coming to our office in the afternoon, you may encounter this super-cute dog. Since she’s working, it’s best for Liberty if you admire her from afar please refrain from approaching her. By doing so, you’ll be contributing a little tiny bit to Liberty’s training.
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This Week’s 1-Page Health News:

Mental Attitude: Misfiring in Brain Linked to OCD.
Researchers at the University of Cambridge have found that obsessive-compulsive disorder (OCD) may be caused by a misfiring of the brain’s control system. Individuals with OCD have frequent upsetting thoughts that they try to control by repeating certain rituals or behaviors. The study involved scanning the brains of 37 individuals with OCD and the brains of 33 individuals who did not have the disorder as they all performed a specific activity to avoid a mild electric shock. The researchers found that OCD participants were unable to stop the specific activity, which revealed overactive brain activity in the caudate (an area of the brain that controls habits) and suggests OCD compulsions may be caused by the habit system in the brain.
American Journal of Psychiatry, December 2014

Diet: Cherry Juice Accelerates Recovery After Cycling.
Montmorency cherry juice appears to help cyclists recover after a hard cycling workout. Researchers found that Montmorency tart cherry juice helped to speed up recovery, maintain muscle function, and reduce markers of inflammation in cyclists who participated in a simulated race.
Cherry Marketing Institute, December 2014

Exercise: Ability to Balance May Reflect Brain Health.
According to new research, the inability to balance on one leg for 20 seconds or longer may signal brain damage in otherwise healthy individuals. In a recent study, participants were asked to balance on one leg up to 60 seconds, received an MRI of the brain, and completed a test to measure cognitive impairment. Those who were unable to balance on one leg for more than 20 seconds showed evidence of cerebral small vessel disease as well as lower cognitive function scores. The researchers add that long-term studies are needed to verify these findings and fully assess the significance of postural instability.
Stroke, December 2014

Chiropractic: Neck, Shoulder, and Back Pain Among High School Students.
Chinese researchers evaluated questionnaires completed by 3,600 high school students and found that 41.1% had experienced neck/shoulder pain and 32.8% had experienced back pain during the previous year. The researchers identified physical inactivity (increased sedentary behavior / low levels of physical exercise), heavy backpacks, mental stress, and insufficient sleep as risk factors for neck, shoulder, and back pain in the high school student population.
Journal of the Chinese Medical Association, October 2014

Wellness/Prevention: Young Children Need Eye Screening.
Experts from the United States National Center for Children’s Vision Health say that all children should have their eyesight evaluated yearly between the ages of three and six. Children in this age group require screening to detect vision issues such as amblyopia (“lazy eye”) and strabismus (a disorder of eye alignment), which can require glasses. Dr. Anthony Adams, the editor-in-chief of the journal Optometry and Vision Science, adds, “Unfortunately, many children receive neither appropriate screening to help identify those who need immediate eye attention, nor a comprehensive examination by an eye care professional, prior to beginning school.” The goal of the new guidelines is to ensure that pre-school children with vision problems are identified and receive appropriate eye examinations and follow-up care to help ensure their development and readiness for elementary school.
Optometry and Vision Science, December 2014

Dr. Glenn Hyman’s Denver Chiropractic Center: Car Accident Injuries (Whiplash) Self-Care: Part 2

 

Last month, we started the discussion of self-care options in the management of car accident injuries: whiplash or CAD (cervical acceleration-deceleration) or WAD (whiplash associated disorders). In this series, we are describing various treatment methods that you can be taught to help facilitate in the management process during the four stages of healing (acute, subacute – discussed last month; remodeling and chronic – addressed this month).

 

Like in the acute and subacute stages, many of the same self-care techniques can be applied here as well. You will NEVER “hurt” yourself with ice or ice/heat combinations (done properly), so they can be continued indefinitely. Many patients find this helpful. Using the analogy of a cut on the skin, in the acute stage, the cut is fresh and new. It is quite pain sensitive and unstable and it will continue to bleed if you don’t take it easy. After 72 hours (entering the subacute stage), the wound has an immature scab on it and it can still easily be re-injured, and if this occurs, especially by NOT self-managing properly, the recovery time can be significantly prolonged. So, “DON’T PICK AT YOUR CUT!!!” As we enter the later subacute phase (fourteenth week), the wound’s scab is quite mature, and self-care can be appropriately more aggressive. Think strengthening and activity restoration!

 

Stage 3 – REMODELING phase (14 weeks to 12 months or more): In this stage, we are now three months to a year out from the injury date and hence, we SHOULD now be more “aggressive” with care. During the late acute and subacute stages, you would have been performing exercises focused on movement restoration (range of motion / ROM exercises with LIGHT resistance) in addition to self-applied myofascial release techniques using foam rolls, tennis balls, TheraCane, and/or the Intracell (and possibly others). It is NECESSARY to continue the use of these methods, as they help reduce the chances for any scar tissue to become permanent. In this stage, we will guide you into more advanced exercises that include aerobics (walking, walk/run combinations, etc.) as studies show that whole body aerobic exercise helps MANY specific area injuries, including WAD/CAD injuries.

 

Stretching short/tight muscles, working on balance-challenging exercises (rocker or wobble boards, balance beams, gym balls, eyes closed specific action movements) are VERY IMPORTANT, as they retrain your neuromotor system and reintegrate neural pathways that have been disrupted by the injured tissues and retrain faulty movement patterns you’ve developed from compensating due to pain. Strengthening exercises will include the core since the head sits on the neck, the neck on the trunk, the trunk on the legs, and ALL of this sits on the feet (so we’ll even consider stabilizing the sub-talar joint at the ankle and if pronation is excessive, foot orthotics can help whiplash patients)!

 

Stage 4: CHRONIC (Permanent): ALL OF THE ABOVE can be employed after the one to two year point to “maintain” your best level of function. If you still have pain, try to “ignore it” and KEEP MOVING, stay active, stay engaged in work, family activities, and DON’T let the condition “win.” AVOID CHRONIC DISABILITY by staying active and fit!

 

We realize you have a choice in whom you consider for your health care. If you or someone you know needs help recovering from car accident injuries, call us at 303.300.0424, or use the “Make an Appointment” function on our website www.denverback.com.

Dr. Glen Hyman’s Denver Chiropractic Center: Whiplash Self-Care: Part 1

 

Whiplash is a condition that can occur from MANY causes – in fact, anything that results in a sudden change in the head/neck position. Usually, there is a rapid acceleration that injuries the soft tissues around the neck area by stretching them beyond their limits. Hence, the more accurate terms for whiplash are, “cervical acceleration-deceleration” or CAD as it describes the mechanism of the injury and “whiplash associated disorders” (WAD) describing the degree of injury.

 

Most commonly, when we think about whiplash, we immediately envision a motor vehicle collision (MVC), but prior to the invention of the automobile, the term “railroad spine” was coined to describe injuries to the neck from crashes that occurred between trains. Since then, due to pilots landing planes on aircraft carriers, sports injuries, and the rise of the automobile, this once rare condition has affected MOST of us at some point in time!

 

Today’s topic will focus on self-care. What can you and I do for ourselves WHEN we suffer a CAD injury? Since there are different levels of injury severity, keep in mind that EACH CASE IS UNIQUE and we will ONLY be discussing general options. So ALWAYS let your symptoms guide you in the process of care – that is, if you feel a sharp, piercing/stabbing, activity or movement stopping type of pain, STOP!!! Don’t further injure your tissues!!! We will discuss a common WAD II injury (soft-tissue injury limiting motion but not injuring nerves) and we’ll look the acute and sub-acute stages of the injury.

 

Stage 1 – ACUTE: The inflammatory phase (up to 72 hours). ICE is necessary to decrease swelling (inflammation). Limit motion but try NOT to use a collar unless you have no choice as even small movements that avoid the sharp/knife-like pain are better than no movement at all. A collar may be needed when driving (especially if the roads are bumpy)! Anti-inflammatory herbs like ginger, turmeric, boswellia, bioflavonoid, and others reduce inflammation WITHOUT irritating the stomach, liver, kidneys, and will NOT inhibit the chemicals needed for healing (like NSAIDs do!). Chiropractic care with Active Release Techniques Soft Tissue Treatment SHOULD begin ASAP after an injury. We may only use gentle manual traction and/or mobilization, also staying within reasonable pain boundaries. It’s been well proven that early movement is best!

 

Stage 2 – SUB-ACUTE: The repair phase (72 hours to 14 weeks). Ice can continue if it helps control pain. You can also alternate ice and heat at 10/5/10/5/10 minutes, starting and ending with ice (it “pumps” the tissues). Cervical range of motion (ROM) exercises with LIGHT resistance (use 1 or 2 fingers against the head and push in a forward, backward, sideways, and rotating directions first with “isometrics” – not moving the head, and when tolerated, “isotonic” – moving the head against the LIGHT pressure applied in BOTH directions within the range that avoids sharp/knife-like pain. Movement, strength, pain, and coordination are ALL better managed when light resistance + motion is used vs. not moving (isometrics). Self-applied methods of performing “myofascial release” (which we will teach you) include: Self-massage, the use of a tennis ball and/or foam roll and others. During this repair phase, chiropractic adjustments and Active Release Techniques Soft Tissue Treatments REALLY help!!! We will continue this discussion on the next page…

 

Whiplash Recovery

Exercise is an important part of whiplash treatment and is often overlooked by both patients and doctors. We will focus on several practical and effective exercises over the next several Health Updates. The first of this series can be called “brain exercises.”

The following URL offers you a 37 page PDF of a booklet that contains GREAT information and includes the exercises reviewed below:

http://tinyurl.com/WhiplashExercises

            Brain Exercise #1: Eyes Still, Move Head. Hold a pen a comfortable distance in front of your eyes and keep looking at it as you rotate your head from side to side ten times. Stop if you feel dizzy but keep trying after resting. Repeat three times a day.

            Brain Exercise #2: Head Still, Move Eyes. Keep your head still (move only your eyes) while you move the pen left to right as far as you can ten times without losing sight of the pen. Stop if you feel dizzy but keep trying later in the day. Repeat three times a day.

Brain Exercise #3: Standing Balance Test. Stand with your feet close together (or, feet shoulder width apart if you feel unsteady). You should feel steady for 30 seconds with your eyes open AND closed. Try it (count to 30)! If you feel unsteady, this exercise should be repeated often until you feel improvement with the eyes closed! A variation is to place one foot in front of the other, switching feet after each test. Notice this one is more difficult. A third position is standing on ONE foot (switch sides after each test) with the eyes open AND again closed. This one is REALLY hard! Stand near a counter or corner of a room to “catch” yourself – don’t fall.

Notice that these exercises are NOT neck specific; there are others exercises for that. Rather, these incorporate eye / head movements, coordination/balance challenges and address symptoms such as dizziness, headache, post-concussion symptoms (memory loss, difficulty concentrating, etc.), and others. These exercises can be very helpful as they “exercise” our neuropathways, or the “wiring” within our nervous system so that information flows freely to and from our brain, spinal cord, and our various body parts. These help us function safer and better in ALL of our desired daily activities! We can train you in these exercises if you feel uncomfortable doing these on your own.

We realize you have a choice in whom you consider for your health care and we sincerely appreciate your trust in choosing Dr. Glenn Hyman’s Denver Chiropractic Center for those needs.  If you, a friend, or family member requires care for Whiplash, we would be honored to render our services.

Whiplash – Can We Predict Long-Term Problems?

Whiplash (or the rapid acceleration forwards followed by deceleration or sudden stopping of the moving head during the whiplash event) occurs at a speed that is so fast, we can’t prepare for it. In other words, by the time it takes us to voluntarily contract a muscle to guard ourselves against injury, that rapid forward/backwards “whipping” of the head and neck is already over! When considering the details of the injury event, sometimes we lose focus on what REALLY matters. Is there a way to reduce the chances for a long-term chronic, disabling, neck pain / headache result? Last month, we found out that the long-term use of a cervical collar is NOT a good idea. What are some other ways to prevent long-term disability?

A very interesting study investigated the first 14 days of treatment during the acute stage of whiplash neck sprain injuries following a car accident. The researchers wanted to determine what long-term consequences resulted from two different treatment approaches. In one group (201 patients, 47% of the total group), the patients were encouraged to, “…act as usual,” and continue in their normal daily, pre-injury activities. The patients in the second group were given time off from work and were immobilized in a soft cervical collar during the first 14 days after the car crash. At the end of the 14 days, there was a significant reduction of symptoms between the first visit to the fifteenth day (24 hours after the 14 day initial treatment time frame in both groups). However, when evaluated at the six-month point, the group that continued their normal daily routine, did not take time off work, and did not wear a collar had, “…a significantly better outcome,” compared to the other group. This study supports that over-treatment with a collar and time off from work “sets people up” for adopting a “sick role” where the patient is overly-focused on their problem. This study parallels what we discussed last month and embraces the chiropractic philosophy to staying active, exercise, don’t use a collar, and the use of manipulation which exercises joints and keeps them from stiffening up, thus reducing pain and the fear of doing activity!

Another study looked at different presenting physical factors that might be involved in the development of long-term handicaps after an acute whiplash injury in a group of 688 patients. They measured these physical factors at three, six, and twelve month intervals and found the relative risk for a disability a year after injury increased with the following: 1) A 3.5 times disability increase with initial high pain intensity of neck pain and headaches; 2) A 4.6 times increase with initial reduced neck movement or ranges of motion; and 3) A 4 times greater chance with initial multiple non-painful complaints (such as balance disturbance, dizziness, concentration loss, etc.). In yet another study, both physical and psychological factors were found to predict long-term disability. These included initial high levels of reported pain and poor activity tolerance, older age, cold sensitivity, altered circulation, and moderate post-traumatic stress.

The “bottom line” is that as chiropractors who also use Active Release Techniques, we are in the BEST position to treat and manage whiplash injured patients based on the type of care we perform and offer. We promote exercise of muscles and joints, encourage activity not rest, and minimize dependence on medication, collars, and other negative treatment approaches.

This Week’s Denver Chiropractic Center 1- Page Health News

This is too cool to not share, but my wife Meredith and our baby sitter Meaghan worked hard to make our Lego costumes for Halloween. I am Lego Captain America. Meredith is Lego Ironman. And Meaghan is Lego Spider Man. A safe and happy Halloween to all!

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Health Alert: Evidence Shows Steroids in Waterways.
Recent research has discovered that common livestock steroids do not fully break down in water as previously believed. Researchers are working to understand the environmental effect of this class of drugs on species that rely on rivers and streams near cattle ranches.
University of Iowa, September 2013

Diet: The Effects of Soy and Whey Protein Consumption on Resistance Training.
A small study looked at the effects of consuming either soy or whey protein prior to resistance training. For fourteen days, male participants consumed either 20g of whey protein, soy protein, or a placebo and then performed six sets of squats at ten reps per set using 80% of their maximum lifting weight. Blood tests showed soy protein appeared to lower serum testosterone levels and whey protein appeared to blunt the effect of the stress hormone cortisol in the body.
Journal of the American College of Nutrition, October 2013

Exercise: When Soccer Injuries Occur…
Researchers have found that soccer injuries are more likely to occur if a player’s team is winning, if the player is a forward (an attacking player), after a yellow or red card is issued against the other team, or as the number of free kicks (a kick right after a foul) increases. According to the study’s co-author, Dr. Jaakko Ryynänen, “The ability to recognize periods of matches (games) when the injury incidence is high may be important in terms of preventive measures.”
University of Gothenburg, October 2013

Chiropractic: Heads Up!
If your head is in a forward posture, it can add up to 30 lbs (~13 kg) of abnormal leverage on the cervical spine (neck). In time, this can pull the entire spine out of alignment. Forward head posture may even result in the loss of up to 30% of vital lung capacity. These breath-related effects are primarily due to the loss of the cervical lordosis (the inward curve of the cervical spine), which blocks the action of the inferior hyoid muscle responsible for helping lift the first rib during inhalation.
Rene Cailliet, M.D., January 1996

Chiropractic again: Adjustments Effective After Low Back Surgery.
A review of 32 patients who received chiropractic care after lumbar spine surgery revealed improvements in pain levels with no adverse effects.
Journal Of Manipulative Physiological Therapy, July 2011

Your head position and strain on your neck

For every inch your head is forward, your upper back and neck muscles have to hold an extra 10 lbs (~4.5 kg), as they have to work harder to keep the head (chin) from dropping to your chest. This also forces the sub-occipital muscles (they raise the chin) to remain in constant contraction, putting pressure on the three sub-occipital nerves. This nerve compression may cause headaches at the base of the skull or mimic sinus (frontal) headaches.
Kapandji, Physiology of the Joints, Volume III

We address this in two ways at Denver Chiropractic Center. We use chiropractic adjustments to realign the spine. We also use Active Release Techniques to release those tight sub-occipital muscles that can cause headaches, neck pain and fatigue.

Car Accident injuries – Whiplash Facts

Whiplash is a slang term for cervical acceleration, deceleration syndrome, or CAD. There are facts and myths surrounding the subject of whiplash. Let’s look at some of the facts.

The origin of CAD. The history of CAD dates back to a time prior to the invention of the car. The first case of severe neck pain arose from a train collision around the time of 1919 and was originally called “railroad spine.” The number of whiplash injuries sharply rose after the invention of cars due to rear-end crashes.

Whiplash synonyms. As stated previously, the term “cervical acceleration-deceleration disorder, or CAD, is a popular title as it explains the mechanism of injury, where in the classic rear-end collision, the neck is initially extended back as the car is propelled forward, leaving the head hanging in space. Once the tissues stretch enough in the front of the neck, the head and neck flex forward very rapidly, forcing the chin towards the chest. This over stretches the soft tissues in the back of the neck. Another term for whiplash is WAD or, Whiplash Associated Disorders. In 1995, the Quebec Task Force categorized injuries associated with whiplash by the type of tissues that were found to be injured. Here, WAD Type I represents patients with symptoms/pain but normal range of motion and no real objective findings like muscle spasm. Type II includes injuries to the soft tissues that limit neck motion with muscle spasm but no neurological loss (sensation or muscle strength). WAD Type III includes the Type II findings plus neurological loss, and type IV involves fractures of the cervical spine.

Head rest facts: Prior to the invention of head rests, whiplash injuries were much more common and more serious because the head was propelled in a “crack-the-whip” like fashion. However, headrests are frequently not adjusted correctly; they are either too low and/or too far away from the head. If the seat back is reclined, this further separates the head from the headrest. The proper position of the head rest should be near the center of gravity of the head, or about 9 cm (3.5”) below the top of the head, or at minimum, at the top of the ears. Equally important is that it should be as close as possible to the back of the head. When the distance reaches 4” away from the head, there is an increased risk of injury, especially if it’s also set too low. When the headrest is properly positioned, the chances of head injury are decreased by up to 35% during a rear-end collision.

Seat back angle. The degree of incline of the seat back can also contribute to injury of the cervical spine. As stated above, as the seat is reclined, the head to headrest distance increases, furthering the chance for injury. A second negative effect is called “ramping.” Here, the body slides up the seat back resulting in the head being positioned over the top of the head rest. Also, the degree of “spring” of the seatback contributes to the rebound of the torso during the CAD process.

Concussion: The notion that the head has to hit something to develop a concussion is not true. Also, the idea that a loss of consciousness is needed to develop a concussion is also false. Simply, the rapid forward/backward movement of the head is enough force for the brain (which is suspended by ligaments) to literally slam into the inner walls of the skull and can result in concussion. The symptoms associated with concussion are referred to as post-concussive syndrome or, mild traumatic brain injury.

We realize you have a choice in where you receive your healthcare services.  If you, a friend or family member requires care for whiplash, we sincerely appreciate the trust and confidence shown by choosing our services and look forward in serving you and your family presently and, in the future.

Car Accidents and neck pain (a.k.a. Whiplash)

Whiplash refers to an injury to the neck resulting from a rapid movement, usually associated with a motor vehicle collision (MVC). However, it can occur with a slip and fall injury, a bar room brawl, during a sports event like being tackled in football, among other things. For the sake of this discussion, we will stick with the classic example of a rear-end MVC.

 Mechanism of injury: So what really happens during the MVC that causes injury? The answer centers around movement of the neck which exceeds the normal tissue’s stretch limits, sometimes referred to as “the elastic barrier.” When the MVC occurs, during the first 100-200 milliseconds the trunk supported by the back of the car seat rapidly moves forwards leaving the head unprotected in its original position resulting in a backward glide or motion of the head and neck. Next, the head (which weighs about 12-15 pounds) drops back (HOPEFULLY) into the headrest stopping the motion, but if the head rest is too far back (>1/2 inch) or too low, then the head keeps going backwards until the tissues in the front of the neck stretch to the point of either stopping the motion or tearing (or both).

Next, the highly stretched front of the neck muscles, ligaments, disks, and tendons (in a “crack the whip” like manner) propel the head forwards to the point of over stretching the tissues in the back of the neck, which similarly stops the movement &/or tears. The degree of injury depends on many things, but is notably worse in the long-necked, skinny female where the “crack the whip” reaction is the greatest. Several factors determine the degree of injury, including the “G-Force,” or the amount of energy produced during the impact. The greater the G-force applied to the head/neck, the greater the potential for injury.

The G-force affecting the occupants inside the vehicle is related to many things: the speed of the crash, the size of the two vehicles (worse if a large automobile hits your smaller car), the angle and springiness of the seat back, the amount of energy absorbed by crushing metal vs. no damage to the vehicles (worse when there is no damage as all the energy is transfer to the occupants), whether the head was rotated or looking straight at impact, and more. The KEY to all of this is that we cannot voluntarily contract our muscles quicker than 800-1000 msec and the whiplash process is over after about 500 msec, so we can’t effectively “guard” or protect ourselves against injury even if we try by bracing ourselves before the MVC!

            Type of injury: The classic injury is called a sprain (ligament tear) and strain (muscle and/or muscle tendon tear) to either or both the front of the neck and/or back of the neck. Sprains and strains come in 1st, 2nd, and 3rd degree tears, getting progressively worse as more tissue is torn. Please refer to previous issues of the Whiplash Health Update where the anatomy is reviewed so you can “picture” this properly.

            Prognosis: The length of time to recovery or maximum improvement varies by the amount of tissue damage. A “prognosis scale,” first introduced in 1995 and validated by 2001, showed that in Type 1 injuries pain without loss of neck motion healed the quickest. Type 2 injuries where neck movement was reduced after the MVC (but no neurological findings occurred) healed next quickest. Type 3 injuries, which included BOTH motion and neurological loss, healed the slowest and had the worst long-term outcomes. Other factors enter into this, of course.

We will continue this “Whiplash 101” discussion next month…

We realize you have a choice in where you receive your healthcare services.  If you, a friend or family member requires care for whiplash, we sincerely appreciate the trust and confidence shown by choosing our services and look forward in serving you and your family presently and, in the future.

Denver Chiropractic Center Weekly Health Update

“If you want others to be happy, practice compassion.
If you want to be happy, practice compassion”
~ Unknown

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Mental Attitude: The Elderly and Facebook.
Elderly adults who learned to use Facebook on a daily basis scored 25% better on tests measuring their cognitive abilities than their peers who did not.
University of Arizona, February 2013

Health Alert: Baby Boomers Vs. Preceding Generation!
As each generation grows older, they believe they are healthier than the previous generation. However, the baby boomers are unable to make this claim. Compared to the preceding generation at the same stage of their lives, fewer have “excellent” health (13% vs. 32%), more have high blood pressure (75% vs. 35%), and more are obese (36% vs. 25%).
JAMA Internal Medicine, February 2013

Diet: The Southern Diet and Stroke.
People from the American South are 20% more likely to have a stroke than those from other parts of the country, and the Southern diet may be to blame. People who eat Southern style food high in fat, sugar, and salt at least 6 times a week were at 41% higher risk for a stoke. People whose diets consisted of fruits, vegetables, and whole grains at least 5 times a week were 29% less likely to have a stroke.
American Stroke Association, February 2013

Exercise: Tai Chi?

Tai Chi may reduce falls among adult stroke survivors. Tai Chi is a martial art dating back to ancient China that includes physical movements, mental concentration, and relaxed breathing.
American Stroke Association, February 2013

Chiropractic: Recommended For Back Pain.
The Royal College of General Practitoners’ 2009 recommendation for treating non-specific low back pain advises doctors to advocate exercise and manipulation (such as chiropractic care) before pharmacological (drug) therapies and more invasive treatments (like surgery).
National Institute for Health and Clinical Excellences, 2009

Wellness/Prevention: Sunshine and Rheumatoid Arthritis.
Routine exposure to the sun, especially ultraviolet B (UVB) rays, may decrease the risk of rheumatoid arthritis. Those with the most elevated rates of exposure were 21% less likely to develop rheumatoid arthritis than who had less exposure.
Annals of the Rheumatic Diseases, February 2013