Work Place Injury Prevention Tracy Ervin, MPT

Transcription

1 Work Place Injury Prevention MSDs and CTDs Tracy Ervin, MPT Worker s Comp Data MSDs account for approx. 55% of WC illness and 65% of WC costs Ergonomics and Office Politics Perception: most workers are faking Reality: 7-10% of injured workers are not credible Physiology of pain Worker attitude is affected by pain and employer response Worker attitude is mistaken for faking Office Politics #1 factor affecting the cost of a work comp claim = supervisor/manager response to the worker s injury Defining Ergonomics Ergonomics is the science of fitting jobs to the people who work in them. Goals: Increase worker comfort Prevent injuries 1

2 Statistics 80% of workers are injured due to worker behavior vs. poor job design (poor ergonomics) Musculoskeletal Work Movement 1/3 of the work the body does every day tendon pulls on muscle that pulls on bone that moves a joint = movement Posture 2/3 of the work the body does every day tendon pulls on muscle that pulls on bone and joint = static posture Posture Where 2/3 of injuries occur Creates a nutrient pathway disorder static contraction of muscles reduces blood supply - this reduces oxygen/nutrients to working muscles and toxins build up in the muscle - creates inflammation Neck Posture Neck neck musculature tightens when doing skilled work with the hands decreases oxygen/blood flow to the limbs the further away from the body the hands are held, the worse the load on the neck and head position Posture - Neck cont d Slouch = 3x the weight of the head on the neck compresses the joints and triples the chance of developing degenerative joint disease at the neck posture muscles are now in a stretched position lose 1/2 the strength of the muscles in this position lumbar curve also reverses in this position - increases compressive forces on the discs 2

3 Posture - Neck cont d Posture - Neck cont d Key exercise for neck and upper extremity pain: Chin tucks - off loads the joints and muscles of the neck and spine Posture - Neck cont d Key exercises: Scalene exercise - don t over-stretch with this - be gentle gently depress opposite shoulder and sidebend away for 10 sec. Repeat other side Exercises Perform exercises every hour Purpose = increase blood supply Exercises are effective in the work place if done correctly Exercises do not slow production - actually increase production Shoulder Risks: Reach - how high and how far More than 60º elevation = increased Rotator Cuff stresses Reducing ht. of reach by 2-3 can decrease load on RC by 20% Load how much and is it sustained? Shoulder Recovery Exercises Codman s Pendulums increases blood supply to shoulder by 400% swing arm in slow lazy circle for 10 sec. - repeat other side 3

4 Elbow Typically affected by what is happening at the wrist or at the neck If from neck - due to forward head posture If from wrist - due to lift, tug, grip, pull, sustained loads (even light loads) Key exercise: Wrist/finger flexion Straighten elbow completely and make a fist Can add ulnar deviation for more stretch - move toward little finger side Hold 10 sec. - shake hand - repeat on other side Elbow Anatomy Small space for a lot of structures Active area Can become irritated easily due to small space Median Nerve is sensitive Neck postures can contribute Wrist Wrist Risks Grip Pinch Flexion/extension position of wrist Vibration Key exercise: Wrist extension exercise palm up, elbow straight, gentle pull of wrist/fingers back Hold 10 sec. - repeat other side Wrist 4

5 Neutral Wrist With Tool Use Elbow biomechanics Too much elbow flexion Better design Shoulder Reaching Risks Forward Head Posture Stress Stress Can damage musculoskeletal tissues by decreasing blood supply to tissues due to tight muscles 5

6 Stress Key exercise to reduce stress: Relaxation exercise Sit upright - inhale & shrug shldrs. and clench fists (don t clench teeth) Hold x3 sec... Relax fully and exhale x5 sec. Repeat again Reduces tension by 95% Computer Ergonomics Position of the body at the work station can create or avoid problems Monitor - midline with symmetrical upright head posture and eyes level with top of monitor Documents should be in midline or close to midline Should have upper extremity weight bearing - use key board on desk top at appropriate height or use properly adjusted arm rests Computer Ergonomics Phone - don t cradle phone to neck Whenever practical - use a handless head set Mouse - close to keyboard to avoid reach Even perfect posture can be harmful if it is sustained Frequent position changes BLINK Chair Computer Ergonomics Slide hips to the back of the chair Sit with low back supported Shoulder blades touch the back rest Knees at 90 degrees or a little less Knees slightly lower than hips Feet flat on floor or on foot rest 8 out of 10 people hurt their backs More lost work days due to back injuries than the common cold billion dollars/year spent on back injuries Why so many injuries 1. Very mobile area 2. Very stable area Spine can t do both of these, but is asked to do both 6

7 Anatomy Spine Structure Curvature in spine acts as a coil spring - increases loading capacity and provides shock absorption Anatomy Vertebral Structure Stacked on top of each other Facet joint - where vertebrae articulate with each other - forms a weight bearing joint Anatomy Discs Two jobs: 1. Shock Absorption 2. Movement Anatomy Discs Body wt. is shared by the facet jt. and the disc when in neutral spine position With forward bend position - stress moves to the back of the disc - can injure disc fibers and weaken disc structure Anatomy Discs Weakened fibers can lead to a bulging disc - can lead to a herniated disc Forward bend is the real issue Occurs in standing and in sitting Ligaments - hold the spine together and limit how much movement can occur if forced - tear ligaments they heal, but with scar tissue structure becomes weakened - more prone to injury 7

8 With forward bend - facet joints only have a partial unstable surface contact with each other, vs. in the neutral spine position where the facet joints fully contact each other get damage to the facet joints due to this edge to edge pressure Ligaments get stretched with forward bend - is the weakest possible position Anatomy Muscles are NOT weak - strongest muscles in the body purpose = stabilize vertebral joints in the neutral spine position relieves ligament/disc strain pulled muscles are rare can get muscle spasm in response to other injured structures such as ligaments, disc, etc. Proper lifting Technique Improper lifting Technique Olympic Clean and Jerk Chen Yanquin (58 Kg class) Olympic Record = 138 Kg Liu Chunhong (69 Kg class) World Record = 158 Kg Sequence Note the neutral spine position throughout the sequence 8

9 Need flexibility to lift properly with the neutral spine and move into a deeper squat Lifting DOES NOT cause back injury injury occurs during lifting to a back that is already compromised due to poor posture/biomechanics/health What compromises the low back? Forward bend Poor flexibility Prolonged sit Key exercise to counter forward bend, sitting, and lifting stresses: Standing lumbar extension push abdomen forward to create extension at the low back and look straight ahead Hold 3-5 sec. - several reps Key stretch for tight hamstrings if sitting or standing a lot: Seated hamstring stretch SEATED - sitting tall - straighten the knee and pull ankle/toes to you - hold 30 sec. on each leg Sitting Often, even in the correct, supported position, the low back will still hurt It s not always the position - it s the time spent in one position Change positions frequently Standing Different than walking - with walking - get muscle contraction/relaxation as weight shifts In standing - static/constant muscle contraction - get joint compression - shuts off blood supply Place anti-fatigue mat under feet or insert in shoes Posture variety is important 9

10 Key exercise to decrease forces on spine due to prolonged stand: Sitting flexion stretch - only do if you spend most of your time in standing - 10 sec. every hour Lifting Two issues: Ergonomics of lift - how high/low, how often, how far, how cumbersome Worker behavior - how does the worker choose to lift? Worker behavior with lifting - poor lifting technique Proper lifting technique Stop and think Foot placement Avoid twist Keep load close to body Neutral spine with lift Back Belts research indicates can decrease back injuries by 32% Back belts will NOT work for workers that demonstrate poor lifting techniques/poor behavior, or with poor ergonomic design See with sustained standing/walking on cement floors Key stretches: door frame stretch - hold 30 sec. Plantar Fascitis 10

11 Key stretch: runner s stretch - hold 30 sec. Plantar Fascitis Alternative stretch to doorway stretch: stair stretch - hold 30 sec. Plantar Fascitis Balanced Lifestyle - Work and Home Taking Care of the Working Body Fitness of the worker is important Stronger/fitter workers don t have to work as hard to do their jobs Strength, endurance, flexibility affect how workers can perform their job throughout the day Taking Care of the Working Body Diabetes the tiny blood vessels that feed tendons, muscles, joints are 3-4x thicker than normal - compromises blood flow to working tissues - people with diabetes more likely to get tendonitis and MSDs Taking Care of the Working Body Thyroid conditions These individuals have irritated connective tissue - more prone to tendonitis and MSDs Rheumatoid Arthritis Symptoms can often be borderline See chronic tendonitis issues that present periodically 11

12 Taking Care of the Working Body Nutrition: What you eat, drink, and smoke affects the health of your body and the body s ability to repair itself Nicotine - breaks down connective tissue in the disk, spine, tendons - at risk for tendonitis, spine problems, and MSDs Taking Care of the Working Body Nicotine - Cont d One study - 92% of workers with tendonitis were smokers 6 wks of no smoking - connective tissue returns to normal Resources Questions cprtherapy.org Tracy Ervin, MPT cprtracy@gmail.com 754 N. College Rd. Ste D