Alabama Department of REHABILITATION SERVICES "for Alabama's children and adults with disabilities" Muscular Skeletal Disorders Michael Papp, MSE Muscular Skeletal Disorders What are MSDs? Muscles Nerves Tendons Ligaments Joints Cartilage Spinal disks What are MSDs? Develop gradually over time Not the result of an instantaneous event, such as slips, trips, and falls Symptoms range from mild to severe chronic and debilitation conditions 1
Signs & Symptoms Aching Burning Cramping Loss of color Numbness Pain Swelling Stiffness Tingling Weakness Carpal Tunnel Syndrome Carpal Tunnel is formed by the wrist bones and a dense ligament Carpal tunnel--a tunnel in the wrist through which the median nerve and nine tendons pass Continued and repetitive pressure on the median nerve in the carpal tunnel can cause carpal tunnel syndrome Carpal Tunnel Syndrome 2
Carpal Tunnel Syndrome How Carpal Tunnel Syndrome Develops Swelling or thickening of the carpal tunnel tendons start Tunnel begins to close Exerts pressure on the median nerve Causes tingling, numbness, pain Carpal Tunnel Syndrome Areas Affected by the Median Nerve Thoracic outlet syndrome Compression of blood vessels and/or nerves between shoulder and arm Numbness of fingers and hand 3
Tension Neck Syndrome Fatigue or stiffness in the neck, neck pain or headache radiating from the neck May occur when neck is held in one position for a long period of time. Alabama Department of REHABILITATION SERVICES "for Alabama's children and adults with disabilities" Ergonomic Risk Factors MSD Risk Factors Awkward Postures Force and Exertion Pressure and Compression Cold Temperatures Excessive Noise Lighting Lifestyle 4
Awkward Postures Two types Static Postures- nonmoving Little movement may occur in neck, back, hips, and legs. Dynamic Postures - body in motion Fingers, arms, and shoulders moving repetitively Force & Exertion Forceful exertions place higher loads on the muscles, tendons, ligaments, and joints Factors Force needed or used to depress key Posture during typing Speed of movement Reduce exertion by reducing: Force needed to press keys Hitting the keys only as hard as necessary Pressure & Compression External Compression Sharp edges concentrate forces on a small area of the anatomy, resulting in high, localized pressure. Internal Compression high-force exertions awkward postures static postures high velocity or acceleration of movement swelling of injured tissue 5
Pressure & Compression Tools & Work Practice Hazards leaning the side of the forearm or elbow on a hard surface. sharply bent wrist positions compression over an extended period of time Cold Temperature Effects Cold environments compromise muscle efficiency Possible vascular and neurological damage Workers with cold-desensitized fingers may exert more force than necessary exposing muscles, soft tissues, and joints to increased forces Cold Temperature Effects Alcohol, nicotine, caffeine, and some medication increase MSD risks from cold temperatures Diseases, such as diabetes, heart, vascular, and thyroid problems, may make a person more susceptible to effects of cold temperatures 6
Noise Effects Increased muscle tension Quicker onset of fatigue Mental stress Reduced concentration Diverted attention Slower recovery time Light Effects Too much or not enough light creates: Awkward postures Muscle fatigue Eye strain Mental fatigue Light Effects Position of light sources Glare on computer screen Eye strain Awkward postures Bright light in field of view Eye strain 7
Life Style Factors Exercise & Activities Proper exercise means Improved health Stronger body Improved endurance Reduced stress Better range of motion No exercise means Easily fatigued Life Style Factors Muscles weaken Easily injured from light activity No endurance Less resistance to illness Life Style Factors Smoking Effects Restricts blood vessels Carbon monoxide in blood Longer recovery from injury Increased injuries from vibration Increased injuries from cold Poor general health 8
Life Style Factors Medication has the POTENTIAL to increase risk of MSDs if it: Lowers or raises normal blood pressure Changes sense of balance Masks pain Relaxes muscles Affects blood circulation Affects eyesight Alabama Department of REHABILITATION SERVICES "for Alabama's children and adults with disabilities" Office Ergonomics If Possible: Reduce Force Used Reduce Repetitive Motions Improve Posture and Position Take Short Rest Breaks 9
Force Press the keys only as hard as necessary to operate keyboard Do not type harder than necessary Repetition Try and reduce the number of keystrokes necessary to perform a task. Utilize keyboard shortcuts and hot keys when available. 10
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Reducing MSD Risk Rest Breaks Short rest breaks allow tissues to recover Research has shown that short rest breaks speed up overall production Hourly output declines though out the day, short rest breaks postpone production loss 13