Ergonomic risk factors for MSDs include repetitive motion, awkward posture, long duration of repetitive activity, lack of recovery time, forceful movement, vibration, uncomfortable conditions (cold, wet), and stressful work organization. Relatively few studies of sufficient quality exist to assess the work-site causative factors associated with MSDs other than back pain, hand/wrist/elbow MSDs, and knee/hip arthritis. Nonoccupational factors such as gender, age, work satisfaction, other additive occupational or recreational activities, and chronic medical conditions and lifestyle practices such as diabetes, hypothy-roidism, arthritis, obesity, pregnancy, and alcohol use are potential confounding factors. There is general agreement that a combination of forces (force, repetition, posture, and vibration) is most strongly associated with carpal tunnel syndrome, tendonitis, and lateral epicondylitis, particularly high force and high repetition. There is also positive evidence for the association of force, repetition, and vibration alone or in combination with carpal tunnel syndrome. There is also positive evidence for force, repetition, and posture alone for tendonitis and force alone for lateral epicondylitis. There is insufficient evidence for posture alone as a risk factor for clinical diagnoses. Shoulder pain syndromes and shoulder tendonitis is positively associated with highly repetitive work and repeated or sustained work postures above 60 degrees flexion or abduction (16-22).
High repetition is considered to be a cycle time of less than 30 seconds or more than half of the cycle spent in an activity and greater than the recovery time. High force is considered to be 6 kg of force or greater. Frequency can also be determined by the work load index, which is the number of pieces handled per hour times the number of hours worked. Other determinants of work-relatedness include regular tasks requiring high force by the hand on the affected side, a job involving frequent, repetitive use of the same or similar movements of the affected hand or wrist, regular use of vibrating handheld tools, frequent or prolonged pressure over the wrist or base of the palm on the affected side, and regular or sustained tasks requiring awkward position (20-22).
The meat processing industry is well known as a high-risk industry for MSDs, and before implementation of a voluntary participatory ergonomics program that was instituted in the early 1990s, the prevalence of repetitive motion injuries was as much as 75 times higher than the general industry rate. Cold is also considered to play an important role in the development of MSDs. Some of the highest incidences of carpal tunnel syndrome occur in frozen food workers and butchers. A four times greater risk of carpal tunnel syndrome occurs in frozen food workers than in those performing repetitive work in normal temperatures (23,24).
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Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.