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What is ergonomics?

 

The term “ergonomics” is derived from two Greek words: “ergon”, meaning work and “nomoi”, meaning natural laws. Ergonomics is the science of using knowledge of human abilities and limitations to design and build for comfort, efficiency, productivity safety. Most doctors are aware of this term but often erroneously associate it with only industrial workers and computer professionals. It however has wide applications and is of implications in working of most human beings from a farm labourer to a cardiac surgeon. In 2003 the US Bureau of Labor Statistics identified nursing homes as the fourth most dangerous workplaces in the United States. They were ranked just behind certain manufacturing sites, busy streets and landfill operations in an 84-workplace sample. It is thus necessary that healthcare setups and doctors have an institutional or personal ergonomic program. The aim of any ergonomic program is to decrease the work related musculoskeletal disorders (MSD) that are developed by people when a major part of their position involves reaching, bending over, lifting heavy objects, using continuous force, working with vibrating equipments , and performing repetitive motions.

 

Some General Suggestions to prevent work related MSDs:

Correct Posture and Stance: All of us could significantly reduce our risk of injury if we could adhere to the following ergonomic principle: Work activities should be performed with the joints at about mid-point of their range of movement. This applies particularly to the head, trunk, and upper limbs.  In order to put these recommendations into practice, a person would have to be a skilled observer of his or her own joint and muscle functioning and would have to be able to change his or her posture to a healthier one at will. No one develops this sort of highly refined sensory awareness without special training. Therefore, in order to derive the benefits of ergonomic research, we must learn how to observe our bodies in a new way.

 

Workplace Analysis: This will help to identify existing and potential workplace hazards and find ways to correct these hazards. Assessment of work tasks involves an examination of duration, frequency, and magnitude of exposure to ergonomic stressors such as force, repetition, awkward postures, vibration and contact stress to determine if we are at risk of pain or injury. Observation of work place and your action with help of a skilled observer and periodic screening surveys may help to identify hazards such as stressful tasks and erroneous working strategies. Ergonomics comes into everything which involves people. Work systems, sports and leisure, health and safety should all embody ergonomics principles if well designed. Use of ergonomic designs in medical and surgical practice starts from as small a thing as changing your conventional chair to one that fits ergonomic principles but are important in maintaining your health in long term.

 

Physical fitness and aerobics: A regular exercise program keeps body fit and muscle toned up. This helps prevent degeneration and tear caused otherwise by sudden unaccustomed activity. It has numerous other benefits and preventing musculoskeltal injuries is on eof the most important advantages.

 

Early identification and treatment of the problem: Healthcare providers are often seeing telling their patients that self medication is wrong but often end up committing the same mistakes ourselves. It is advisable to consult a specialist when ever you feel that pain or disability is affecting your daily activities. An early identification and intervention can keep the treatment short and quick where as late presentation often lead to resistant situation where in the treatment is difficult and often prolonged.

 

 

What are common work related MSDs?

 

MSDs are injuries that affect muscles, nerves, tendons, ligaments, joints or spinal column. Some commonly encountered MSDs are:

 

  • Carpal tunnel syndrome.

 

  • Frozen shoulder

 

  • De Quervain’s disease.

 

  • Tennis elbow.

 

  • Low Back pain.

 

  • Plantar Fascitis

 

 

Carpal Tunnel syndrome: Carpal tunnel is a common painful disorder of the wrist and hand caused by pressure on the median nerve at wrist. The symptoms include:

  • pain, numbness, or tingling in hand and wrist, especially in the thumb and index and middle fingers; pain may radiate up into the forearm
  • increased pain with increased use of hand, such as when you are driving or reading the newspaper
  • increased pain at night
  • weak grip and tendency to drop objects held in the hand
  • sensitivity to cold
  • muscle deterioration especially in the thumb (in later stages).

Although if one has these symptoms it is recommended to see an orthopaedician, some of the following general and ergonomic tips may be helpful to alleviate the symptoms.

  • Elevate your arm with pillows when you lie down.
  • Avoid activities that overuse your hand.
  • Find a different way to use your hand by using another tool or try to use the other hand.
  • Avoid prolonged bending your wrists.

 

Frozen Shoulder: Frozen shoulder also known as adhesive capsulitis, is characterized by slow onset, pain near the insertion of the deltoid, inability to sleep on the affected side, painful and restricted elevation and external rotation, and a normal radiological appearance. It is commonly seen with health care workers who are involved in lot of overhead activity and don’t exercise their shoulder often.

 

 The treatment includes physiotherapy and NSAIDs. Most cases resolves within few weeks to up to 6 months. Rarely manipulation under general anesthesia to break the adhesions or intraarticular steroid injection may be advised. In case of severe pain ice packs 20 – 30 minutes twice daily are helpful.

 

 

DeQuervains Tenosynovitis: Tenosynovitis of the wrist, also known as de Quervain's tenosynovitis (for the Swiss surgeon Fritz de Quervain, who wrote about it in 1895), is a painful inflammation of the thumb side of the wrist. The tendons for the muscles which extend or straighten the fingers and thumb and lift the hand at the wrist pass over the back (dorsal surface) of the wrist. These tendons run through six lubricated tunnels or compartments. When the lining of these tunnels (or extensor sheaths) becomes inflamed, the tendon cannot glide smoothly. If this happens in the first dorsal compartment of the hand, lying over the bony base of the thumb, it affects the ability of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) muscles to spread and extend the thumb away from the rest of the hand. Tenosynovitis of the wrist, once known as "washer woman's sprain," may be caused by anything that changes the shape of the first dorsal compartment or causes the swelling or thickening of the tendon.  Strain from overuse of the wrist or thumb, a direct blow or injury to the muscles and tendons in the wrist or hand, or any inflammatory process are all possible causes of the disease. Sometimes a precise cause cannot be identified.

 

Tenosynovitis of the wrist can often be reversed with a 3 to 6 week management trial on an anti-inflammatory medication. The thumb and wrist are rested and immobilized with the use of a spica splint. Steroid injection may be required to decrease inflammation. Heat treatments are effective in managing pain and increasing blood flow to the injury. Use of heat lamps, heating pads, hot soaks, or whirlpool treatments, are good for symptomatic relief. Very rarely surgery to release the tendon may be needed to relieve the symptoms.

 

 

Tennis Elbow: Tennis elbow is common in people whose occupation requires frequent rotary motion of the forearm (e.g – tennis players, pipe fitters, carpenters and in case of health care workers – orthopedic surgeons and spine surgeons). The onset is gradual with an ache over the outer aspect of the elbow and is often referred into the forearm. The pain is persistent and intensified by grasping or twisting motions. Swelling is rarely present and the movements at wrist and elbow are usually normal.

 

The actual pathology of the condition is unknown but majority of opinions indicate that the condition is caused by a partial tearing of the tendon fibers from their attachments to the epicondyle and the epicondylar ridge. Conservative treatment is effective in most cases, but recurrences are common. Rest is often the only thing that is required. Avoiding the activities that precipitate or aggravate pain would provide relief in majority of cases. Heat in the form of moist compress or short wave diathermy is also helpful. Multiple punctures in the tender area with a needle under local anaesthesia or local hydrocortisone injection can be used in resistant cases. Surgery is indicated when all the conservative management is exhausted and operation involves completely severing of the common extensor tendon origin from its attachment and firm refixation of the tendon origin.

 

Low back pain: Four out of five people will experience back pain at sometime in their life. 90% of these resolve within 6 weeks but symptoms of as many as 75% people remain even after one year of the initial episode. There are many causes of back pain and some of the most common causes include muscle strain, degenerative disc disease, spondylolisthesis, spinal stenosis, herniated disk and osteoporosis. A quick assessment and modification of posture, exercises help in going long way in preventing back pain. Some general postural suggestions are -

 

Standing: Keep your ears, shoulders and hip in one line. Don’t slouch and look straight ahead with your head held high. Maintain the posture by keeping your stomach muscles tight while walking,

 

Sitting: Support your back when sitting and don’t slump or sit too far away from your chair. Keep your knees lower than your hips to allow your back to arch forward slightly. Place your feet flat on the floor on a low stool if your feet don’t reach the floor. To prevent twisting of spine, don’t lean on either side. The shoulders should be relaxed and head, chest should be kept up.

 

Sleeping: Sleep on bed with firm base mattress, and while sleeping on side flex your knees, keeping a pillow in between them. Avoid sleeping on your stomach. While getting up always roll to your side and then get up.

 

Bending and lifting: Always bend through your knees, hips, and ankles so that the object is at the waist level. Don’t bend with your waist. While lifting, bend through your knees, hips and ankles so that the object is at waist level. Maintain erect spinal posture throughout the lift by keeping your head and chest up and your stomach muscles tight.

 

Exercises: Regular exercise, stretch before exercising and loosing weight are important. A session with physiotherapist on aerobic conditioning and back school exercises may also be helpful in those already suffering from back pain.

 

Plantar Fascitis: The characteristic complaint is of pain under the medial aspect of the heel, typically worst on the first step in the morning, improving as the day goes on then often getting more painful towards evening. Some patients have more weight bearing pain than first step pain. The pain may radiate across the heel or down the plantar fascia. Tingling, electric shocks, altered sensation and rest pain should suggest nerve entrapment - tarsal tunnel syndrome, nerve to quadratus plantae, medial calcaneal nerves. It is common in people who have prolonged standing. Treatment includes rest, heat, ultrasound, change of shoe wear, stretching of plantar fascia and Achilles tendon. Arch support and custom molded orthoses also help in reliving pain. Occasionally steroid injection, plaster casting, radiofrequency lesioning may be required to treat intractable pain.

 

 

Conclusion: It is difficult to bring about any process and structural change in one’s life and Machiavelli was right to core when he said “one ought to consider that there is nothing more difficult to pull off, chancier to succeed in or more dangerous to manage, than the introduction of a new order of things”. But then it is essential to invest some time and energy for your own health.