Ergonomically Yours

Archive for May, 2010

By Dr. Steve Jones
My chiropractic clinic is located in San Diego, California.  For whatever reason, we see many patients suffering from neck pain, back pain, shoulder pain, wrist pain and hand pain as a result of computer work.  As we spend increasing amounts of time at our computer workstations, we need to be aware of how the design and arrangement of our equipment can impact our chances of injury.   Computer ergonomics is the study and / or implementation of work station design with the purpose of reducing or eliminating physical stress.
My interest in repetitive stress syndromes began approximately 10 years ago when my practice started seeing a much greater number of people suffering from the effects of computer / keyboard work.  Despite all of my training and continuing education related to these types of injuries, I quickly realized that traditional treatment for this type of injury was marginally successful at best.
Any type of therapy was going to have to include the application of basic ergonomic principals to the patient’s work environment.
I am of the opinion that treatment alone or application of ergonomic principals by themselves was not going to resolve a repetitive stress injury.
This article will address the implication of work station ergonomics and injury resulting from postural stress secondary to use of the computer mouse.
Specifically, the following will be addressed:
1)    What repetitive stress injuries are
2)    What role do work station ergonomics play in injury
3)    How reaching for the mouse sets the stage for injury
4)    What are the symptoms of repetitive stress injury
5)    How one can avoid mouse reaching injuries
What Exactly is a Repetitive Stress Injury?
Repetitive Stress Injury is a kind of catch all phrase for many conditions.  Carpal Tunnel Syndrome, Tenosynovitis / DeQuervain’s Syndrome, Tendonitis, Thoracic Outlet Syndrome, Trigger Finger, Myofascial Pain Syndrome and Chronic Sprain / Strain are some of the actual diagnosis that are rendered in my office.  All of these conditions are serious and in many cases can cause great pain, permanent disability and sometimes loss of employment.
Repetitive Stress Injuries occur from repetitive movements involving a specific set of muscles and joints.  RSI injuries are the result of an accumulation of stress and strain that causes irritation, inflammation, and eventually pain or other disability.  A good analogy used to characterize the onset of RSI would be the “straws on the camels back” saying.
Initially, RSI affects the soft tissues of the involved joint(s).  Soft tissues include muscles, nerves, ligaments and tendons.  However, if left untreated for long periods of time, the involved joint can become arthritic and form bone spurs resulting in permanent damage to the joint.
While various occupations ranging from meat cutters to construction workers develop RSIs that result from the typical duties of their professions, the most frequent cause of these injuries involve computer work.  The constant demand of keyboarding and mousing combined with the postural stress of confinement in an office chair with one’s neck and back held in prolonged fixed positions has resulted in an epidemic of injuries that includes hand pain, wrist pain, arm pain, neck pain, back pain and shoulder pain.
Work Station Ergonomics
The study of workstation ergonomics tells us that the objects that are used most often should be located closest to your body and accessed easily, without awkward body positions.  Repeated reaching or prolonged postures that involve leaning forward from your chair are particularly stressful and fatiguing.
Many people are aware of computer ergonomics and thus have an ergonomic mouse.  An ergonomic mouse is of little use if it is positioned in an area that requires reaching and stretching in order to operate it.   Limiting reaching and stretching for desk items is essential to maintaining a healthy ergonomic environment.
The most frequent complaint that I have seen in my office is due to computer work is the combination of mousing and its’ inherent postural stress.
Most computer stations are designed in a way that involves the worker operating the computer mouse on a pad on the desk.  Reaching to the desk for the mouse places direct stress on the joints and soft tissues of the neck, shoulder, elbow, wrist and hand.  Additionally, reaching forward for the mouse stresses the lower and middle back.
So How Does Reaching for the Mouse Set the Stage for Injury?
Reaching for the mouse causes you to lean forward in your chair, extend your arm and support the weight of your body through your extended arm.  The following section will discuss the particulars of each of these positions.
The stresses placed on the human frame when reaching for the mouse are easily explained.  Contrary to popular belief, sitting, which most people believe is relaxing, is hard on the back. Sitting for long periods of time can cause increased pressure on the intervertebral discs of the spine.
In recent years, ergonomisist have told us that proper sitting posture would have us sitting upright with our hips flexed at 90 degrees.  As it turns out, the most up to date studies show that a slightly reclined sitting posture with the hips flexed at 100 to 115 degrees is ideal if you have to sit at a desk.  If your mouse is not positioned close enough to your body, you will have to reach for it.  Reaching for your mouse stresses your back by reducing the angle of your hips.
Next, we have to look at the effects of reaching on the neck and shoulder.  When the mouse is being operated at a distance that makes the operator reach, the shoulder extends forward and the shoulder blade abducts (rotates forward).  This position stretches the muscle groups that connect the medial portion of your shoulder blade to your spine and the superior portion of your shoulder blade to your neck.  In the short term, this stretch aggravates the affected muscle groups causing spasm, fatigue, headaches and stiffness in the neck and shoulder.  In the long term, this position creates a condition called a “stretch weakness” resulting in muscular imbalance, trigger points and chronic variations of the conditions listed in the prior sentence.
Lastly, placing the mouse too far away, too low, or too much on one side can cause shoulder, wrist, elbow, and forearm discomfort. When the operator is forced to reach for the mouse, his / her body weight shifts forward and ultimately results in weight bearing stress on the extended arm.  Spending prolonged periods of time leaning on an extended arm is an unnatural and destructive posture that will eventually lead to the development of a repetitive stress syndrome; likely resulting disorders would include tendonitis of the wrist, elbow or shoulder.
What are the Common Symptoms?
•    Tightness, discomfort, stiffness, soreness or burning in the hands, wrists, fingers, forearms, or elbows
•    Tingling, coldness, night pain or numbness in the hands, especially around the base of the thumb
•    Clumsiness or loss of strength in the hands
•    Pain in the neck, shoulders, wrists, hands or back that is associated with using the computer
How Can You Avoid Injuries Related to Reaching for the Mouse?
The following recommendations are applicable to both home office ergonomics as well as ergonomics in the office.
1)  Placing the input device directly in your immediate reach zone offers natural comfort and maximum hand-eye coordination.  The use of a platform for the mouse is preferable.  Some models of mouse platforms attach directly to your chair.
2)  Your chair should have arm rests that are adjustable.
3)  Your wrist should be either in a neutral position or flexed slightly downward when operating both your mouse and your keyboard.   For this reason, if you select a mouse platform that attaches to your chair, adjustability of the platform is of primary importance.
4)  Consider using a high quality office chair with adjustable armrests and lumbar supports.  It should also allow some degree of recline.
5)  Make sure that the upper arm and elbow are as close to the body and as relaxed as possible for mouse use – avoid overreaching.
6)  Hold the mouse lightly, don’t grip it hard or squeeze it. Place the pointing device where you don’t have to reach up or over very far to use it.  The closer you can place it to your body the better.

Sitting is a pain in the @#$%&! Or at least a pain in the back.

Our spines do not like sitting as a rule. If you remain seated in the same position for a long enough period of time you will experience some level of discomfort.

Although there are many reasons that sitting eventually causes discomfort, one of these reasons cannot be avoided. The natural center of gravity for a sitting human being is approximately 1 inch in front of the belly button. In order to park our upper bodies over our center of gravity we have to either lean forward eliminating the support of our backrests or slide our butts downward and forward assuming a slumped position. Often these postures are accompanied by crossed legs or feet and leaning our elbows on the desk or our armrests in order to promote stability of the spine.

Poor posture often results from chairs and work stations that are void of proper ergonomic considerations. Postural stress causes discomfort in the neck, back and arms resulting in fatigue and fidgeting. It comes as no surprise that these consequences of poor posture have a negative effect on your mood, your concentration and your productivity.

In the long run, poor posture can cause chronic back pain, neck pain and a host of syndromes that affect the upper extremity as a whole.

I found an excellent definition of poor posture in a book called “Backs” by Leonard Ring in which he defined poor posture as “a faulty relationship of the various parts of the body which produces increased strain on supporting structures”.

As important as proper sitting posture is for a younger person with an otherwise healthy back, it is of much greater importance to those who are older and may have some level of arthritis in their spines or a history of injury. Arthritis weakens the joints in the back and makes it more sensitive to the stresses of prolonged sitting when using good posture and much more likely to suffer consequences in situations that involve poor posture. A history of back injuries is also detrimental to the spine during sitting positions especially when it is exposed to the stress of poor posture. All of those old gymnastics, football, hockey and general horseplay falls and jolts have a cumulative effect that decreases our ability to endure stressful postures.

The bottom line is that there are many good sources on the Internet that describe the characteristics of proper sitting positions. The more stress that you can eliminate from your sitting postures the happier your back will be.

Here’s To Your Health

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Yours Ergonomically,
Steve Jones

Ergonomic Office Supplies

San Diego Chiropractor

(619) 280-0554

The other day I had a new patient walk into my San Diego, California office asking for chiropractic treatment.  He was bent over 45 degrees at the waist, complaining of lower back pain and saying “Doc, Why do I have back pain?  I have no idea how I got this way but I am having trouble standing up and sitting down, can you help me?”  This is a common new patient presentation in our office.  More often than not, the typical back pain patient can’t recall a specific cause of their back pain.  Sometimes the pain has advanced enough to affect the nervous system resulting in sciatica nerve pain.

Patient’s like this always want an explanation as to how they got the way they are.  Most of my patients have followed a typical course on their way to experiencing back pain.

The joints, muscles and ligaments that allow movement, move the body and provide stability in the low back are among the biggest and strongest in the body.  This being the case, it usually takes a significant single injury to damage these structures.  A hard fall, car accident or a long day of strenuous lifting are examples of single events that can cause back pain all by themselves.

However, most cases of back pain are caused by cumulative stress.  Cumulative stress comes from postural stress (excessive sitting), poor lifting habits, awkward sleeping habits, etc.  Cumulative stress also known as repetitive stress takes place over months or sometimes years.

The bottom line is that most back injuries arise from events that seem small and insignificant by themselves but after months or years of exposure to these stresses lead to irritation of the joints and muscles resulting in back pain.

Once the joints, muscles and ligaments of the lower back have been exposed to extended periods of stress, they become very vulnerable to injury.  This process follows a predictable path.  The joint is stressed by some activity, the stress irritates the soft tissues of the joint, the irritation causes inflammation and the inflammation causes pain and scar tissue formation.  Scar tissue limits joint motion, causes pain in the joint and is often sensitive to changes in weather. We all know someone that knows better than the weather man as to when it is going to rain.  It is scar tissue build up and arthritis that causes joint pain when it is going to rain.

Once this process has begun, a severe case of back pain can arise from something as simple as picking a sock up off the floor or reaching for a cup of coffee.

Unfortunately for the patient, the little things that they do on a regular basis that stress their backs don’t become apparent until after they are in pain.  I always advise my patients to pay special attention to the specific activities or movements that aggravate their backs while they are in pain.  These are the activities that are often responsible for the cumulative stress that I discussed at the beginning of this article.

Joints are complex structures that in most cases are very durable and work without pain.  However, the process described above can happen silently, over time, resulting in severe back pain and / or sciatica for the person who has ignored proper back care through the course of their lives.  Chiropractic care from a licensed chiropractor can be very effective in relieving your back pain.  Chiropractic care is a safe, effective and affordable form of treatment that has a history of success with relieving low back pain.

Key: chiropractic,back pain,chiropractor,sciatica,low back pain,chiropractic treatment,nerve pain

Bio for Article city
Dr. Steven R. Jones is a licensed Chiropractor in the state of California.  He received his doctorate from Palmer College of Chiropractic-West in Sunnyvale, California.  Dr. Jones has treated his patients for over 15 years at his own San Diego Chiropractic practice.  Dr. Jones is accepting new patients and would be happy to consult with you regarding your chiropractic needs.  Click the following links to find out how we can help you start feeling better today!  www.JonesPainRelief.com   www.ErgoNav.com
Back Pain,Chiropractic,Herniated Disc,Pinched Nerve,Neck Pain,Muscle Spasm

Dr. Steve Jones is a licensed Chiropractor in San Diego.  Dr. Jones has treated his patients for over 15 years at his own San Diego Chiropractic practice.   Dr. Jones is accepting new patients and would be happy to consult with you regarding your chiropractic needs.  Click the following links to find out how we can help you start feeling better today! www.JonesPainRelief.com, www.ErgoNav.com

Dr. Steve Jones is a licensed Chiropractor in San Diego.  Dr. Jones has treated his patients for over 15 years at his own San Diego Chiropractic practice.  He is certified as a Specialist in Health Ergonomics.  Dr. Jones Can be found on the web at www.JonesPainRelief.com & at www.ErgoNav.com

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Here’s To Your Health

Yours Ergonomically,

Dr. Jones

Economic Mouse Pad
San Diego Chiropractic
Pain Relief San Diego Chiropractic

(619) 280-0554