Workplace Ergonomics: Understanding and Preventing Musculoskeletal Disorders and Injuries

1. Workplace Ergonomics: Understanding and Preventing Musculoskeletal Disorders and Injuries Part I: Introduction to Ergonomics and Musculoskeletal Disorders Developers: Margaret Nuesca and Karen Traicoff (Occupational Therapy Students) Project Advisors: Tiffany Boggis, MBA, OTR/L and Zachery Collins, MOTR/L, CEAS Director, School of Occupational Therapy: John White, Ph.D, OTR/L Spring 2010

2. Ergonomics: What is it? • Definition: The scientific study (Greek – nomos) of human work (Greek - ergon). • Strategy: Ergonomics considers the physical and mental capabilities and limits of the worker as he or she interacts with tools, equipment, work methods, tasks, and the working environment. • Goal: Reduce work-related musculoskeletal disorders (WMSD’s) by adapting the work to fit the person, instead of forcing the person to adapt to the work. Source: OR-OSHA 201: Introduction to Ergonomics

3. Ergonomics: Why it matters • Ergonomics prevents the inadvertent injury of workers, who are a valuable resource. • Musculoskeletal disorders are preventable and unnecessary injuries that: • Cost the US economy billions of dollars annually • Result in missed work, increased pain, and decreased morale among affected workers. • Integrating good ergonomics into job and workplace design costs no more than choosing a bad design. • Good ergonomics programs focus on ways to reduce costs to companies by: • reducing injuries - reducing errors • reducing absenteeism - maximizing productivity • Good ergonomics programs are ALWAYS cost-effective - they save more than they cost. Source: http://ergo.human.cornell.edu/CUproERGO.html

4. Role of Supervisors in Ergonomics • Supervisors assist in assuring safety in the workplace as the person working most directly with the employee • Supervisors utilize knowledge about workplace hazards to reduce risks in the work environment in order to keep employees safe • Supervisors watch for signs of employee pain or discomfort, encourage early reporting of symptoms, and assist in obtaining an ergonomic evaluation. • Important to report symptoms early: not reporting early will increase severity of injury and related costs

5. Role of Occupational Therapy • Interested in getting people back to doing: • Work • Play • Leisure • Ergonomics are important to OT’s because an ergonomically friendly workplace enables individuals to prevent injury and work to their fullest potential.

6. What are Musculoskeletal Disorders (MSDs)? • Illnesses and injuries of the musculoskeletal system that can have a work-related causal component. • Include: • 29% of all workplace injuries in the U.S. requiring time away from work are caused by work-related MSD’s (Bureau of Labor Statistics, U. S. Department of Labor, 2008)

7. What kinds of Injuries are Musculoskeletal Disorders (MSDs)? • Acute Injuries • Happen immediately due to overload • Can become chronic • Re-injury possible • Strains, sprains, disc herniations • Chronic Injuries • Pain or symptoms lasting more than a month • Cumulative Trauma • Happen over time • Difficult to cure

8. Specific MSDs(by body part, from NIOSH) Click on the for more info When finished, click here to continue

9. Carpal Tunnel Syndrome (CTS)(Claiborne, Powell, Reynolds-Lynch, 1999) • Result of median nerve compression within the carpal tunnel • Carpal tunnel is composed of eight irregular shaped carpal bones covered by the tough fibrous flexor retinaculum. • Tunnel contains the finger flexor tendons and the median nerve. • Median nerve innervates most of the palm, thumb, index finger, middle finger, and radial border of the ring finger Retrieved from: http://www.mdconsult.com/das/patient/body/188016560-2/0/10041/34700.html • Flexor tendon sheaths that become swollen may impinge on the median nerve within the cramped carpal tunnel. • Symptoms of CTS include: numbness, tingling, and pain in the distal distribution, and may commonly wake patients during the night. • In advanced cases, symptoms may persist during the day, person may drop objects frequently owing to decreased sensation, and thenar muscle atrophy. • Click here to return to previous page

10. De Quervain’s Disease (Claiborne, Powell, Reynolds-Lynch, 1999) • A form of tenosynvitis affecting the first dorsal (extensor) compartment of the hand. • The extensor pollicis brevis and abductor pollicis longus are involved. • The sheath of the tendons on the thumb side of your wrist become inflamed or swollen, making it difficult to move. • Symptoms include a dull aching sensation over the tendon, discomfort with specific movements (grasping or turning wrist), and tenderness to touch. Retrieved from: http://mapleleafpt.com/index.php?page=library&list=wrist&article=39 Click here to return to previous page

11. Elbow Tendonitis(Claiborne, Powell, Reynolds-Lynch, 1999) • Also known as “tennis elbow”, affecting the outer part of the elbow • Inflamed unsheathed tendon that may become frayed or torn apart when repeatedly exerted and tensed. • Tendon may become thickened, bumpy, and irregular. • May be caused by repetitive motions, which aggravate the tendons needed to perform the task. • Tendons without sufficient rest and recovery time may become permanently weakened. Retrieved from: http://www.mdconsult.com/das/patient/body/188016560-2/0/10041/30150.html • Symptoms include a dull aching sensation over the tendon, discomfort with specific movements, and tenderness to touch. • Click here to return to previous page

12. Epicondylitis(Claiborne, Powell, Reynolds-Lynch, 1999) • Also known as “golfer’s elbow”, affecting the inner part of the elbow. • This is another form of tendonitis affecting the wrist and digit flexors where they originate at the medial epicondyle of the elbow. • May be caused by excess or repetitive motions in the wrist and fingers (such as typing), or a sudden force to the elbow or wrist. Retrieved from: http://www.colinmcnulty.com/blog/2008/02/25/i-have-medial-epicondylitis-aka-golfers-elbow/ • Symptoms include a dull aching sensation over the tendon, discomfort with specific movements, and tenderness to touch. • Click here to return to previous page

13. Rotator Cuff Tendonitis (Claiborne, Powell, Reynolds-Lynch, 1999) • Also known as supraspinatus tendonitis, subdeltoid bursitis, subacromial bursitis, and partial tear of rotator cuff. • The four rotator cuff tendons provide the shoulder with mobility and stability • These tendons internally and externally rotate and abduct the arm • Repeated overhead motions result in wear and tear of the tendons as they pass between the humerus and acromion process • Symptoms include a dull aching sensation over the tendon, discomfort with specific movements, and tenderness to touch. Retrieved from: http://www.walkerpt.com/library_shoulder_31 Click here to return to previous page

14. Thoracic Outlet Syndrome (TOS)(Claiborne, Powell, Reynolds-Lynch, 1999) • A neurovascular (nerves & blood vessels) compression between the neck and shoulder. • The thoracic outlet is composed of the anterior scalene muscle, medial scalene muscle, clavicle, and first rib. • Activities and postures of the upper extremity can impede circulation by putting pressure on the blood vessels within the thoracic outlet. • Decreased circulation results in oxygen and nutrient deprivation to surrounding tendons, ligaments, and muscles. • Muscle recovery and activity duration are slowed and limited Retrieved from: http://spectrum2105.com/thoracic_outlet_rotator_cuff • Common symptoms of TOS include pain, paresthesias, and weakness in the involved arm • Symptoms often follow the ulnar nerve distribution in the hand (little finger and ulnar side) • Click here to return to previous page

15. Tension Neck Syndrome(Ergomatters, 2010) • Also known as “tech neck”. • Results from performing activities with the neck in flexion or rotation (e.g., holding phone with shoulder, turning neck to the side to look at a document while typing) • Symptoms may involve stiff neck, neck or shoulder tension, knots in the shoulders, tight chest, numbness and tingling in the forearm down to the fingers. Retrieved from: http://www.kulpphysicaltherapy.com/neck.html • Headaches may occur due to prolonged periods of looking up or off to the side, or holding arms extended, rounded shoulders, pain between the shoulder blades. • Click here to return to previous slide

16. Disc Herniation • Also known as bulging disk, compressed disk, herniated intervertebral disk, prolapsed disk, slipped disk • Results in a less elastic spinal disk, nerve becomes pinched • May have occurred suddenly from a fall or an accident, or may occur gradually with repetitive straining of the spine Retrieved from: http://www.drpepperchiro.com/custom_content/111118_dts_spinal_decompression.html • Symptoms may include back pain that spreads to the buttocks and legs when herniation is in lower back, neck pain that spreads to the shoulders and upper arms when herniation is in upper back, tingling or numbness, muscle spasms or weakness • Click here to return to previous page

17. Back Pain • Also known as back strain • Back pain can arise from problems with any of the structures that make up our back (bones, muscles, ligaments, tendons, and disks) • May occur from strained muscles and ligaments, improper or heavy lifting, or after a sudden awkward movement. • Some problems may also occur from lack of movement – constantly sitting • Symptoms may include muscle ache, shooting or stabbing pain, pain that radiates down your leg, limited flexibility or range of motion of your back, inability to stand straight Retrieved from: http://www.clarian.org/ADAM/doc/SeniorsCenter/28/000393.htm Click here to return to previous page

18. Signs and Symptoms of MSDs Early Warning Signs: • Numbness or burning sensation in hand • Reduced grip strength in the hand • Swelling or stiffness in the joints • Pain in wrists, forearms, elbows, neck, or back • Reduced range of motion in the shoulder, neck, or back • Dry, itchy, or sore eyes • Blurred or double vision • Aching or tingling • Cramping • Weakness These signs and symptoms should be reported and are an indicator that an ergonomic assessment should be made.

19. Part I Summary • Musculoskeletal Disorders (MSDs) are illnesses and injuries of the musculoskeletal system that can have a work-related causal component. • MSDs can also be contributed to non-work-related factors. • The goal of ergonomics is to minimize work-related MSDs by adapting the work to fit the person, instead of forcing the person to adapt to the work. • Symptoms of MSDs involve swelling, numbness, tingling, discomfort, burning sensation, irritation, stiffness, pain, and weakness.

20. References Bureau of Labor Statistics, U.S. Department of Labor (2008). Nanfatal occupational injuries and illnesses requiring days away from work, 2007. News: United States Department of Labor, Bureau of Labor Statistics. Claiborne, D. K., Powell, N. J. & Reynolds-Lynch, K. (1999). Ergonomics and cumulative trauma disorders: A handbook for occupational therapists. San Diego: Singular Publishing Group, Inc. Cluett, J. (2009) Herniated disk. Retrieved from http://orthopedics.about.com/cs/herniateddisk/a/ruptureddisk.htm Ergo Matters (2010). Tech-related tension neck. Retrieved from http://www.statefundca.com/safety/ErgoMatters/TechTension.asp Department of Consumer and Business Services (no date). Easy Ergonomics:  A Practical Approach for Improving the Workplace. Retrieved from http://www.cbs.state.or.us/external/osha/pdf/pubs/3347.pdf Harvard Environmental Health & Safety (2010). Computer Workstation Ergonomic Training and Evaluation Program. Retrieved from http://www.uos.harvard.edu/ehs/training/ergo_info.html Mayo Clinic staff (2009). Back pain. Retrieved from http://www.mayoclinic.com/health/back-pain/DS00171 Medline Plus (2010). Herniated disk. Retrieved fromhttp://www.nlm.nih.gov/medlineplus/herniateddisk.html National Institute for Occupational Safety and Health (1997). Musculoskeletal disorders and workplace factors: A critical review of epidemiologic evidence for work-related musculoskeletal disorders of the neck, back, upper extremity, and low back. Retrieved from http://www.cdc.gov/niosh/docs/97-141/ergotxt1.html Oregon OSHA (n.d.). OR-OSHA 201: Introduction to ergonomics (Publication No. 1003-02). Retrieved March 1, 2010, from the Oregon OSHA site: http://www.orosha.org/educate/training/pages/materials.html