Lecture 13 & 14 - Cumulative Trauma Disorders (CTDs)
What could cause hyperlordosis?
- obesity - pregnancy
What is hand/arm vibration syndrome?
- transfer of energy from vibrating tool causes vasoconstriction in the hands and fingers - "white finger" syndrome
What are awkward workstation designs that cause lower back pain?
- work too low - work too high (requires reaching) - work too far away from body - unsupported back
What are the psychosocial factors that contribute to low back pain?
-Monotonous work -Poor social support -High work pressure -Lack of control -Job dissatisfaction -Mutual dislike of boss/co-workers
What are two vascular disorders?
1) Hand/arm vibration syndrome 2) Primary Raynaud's phenomenon
What jobs represent the top 3 occupations with the largest percentage of musculoskeletal injuries?
1)Service occupations 2) transportation 3) material moving
What causes pressure on spinal nerves?
A herniated disc in the lower back can cause lower back pain and/or leg pain (sciatica) by putting pressure on the nerve root.
What causes tennis elbow, pitcher's elbow, and bowler's elbow?
Activities associated with the use of the arm for impact or jerky throwing motions.
What causes bursa disorders?
Can be caused by direct trauma or overuse
Who is at an increased risk of osteoarthritis?
People standing on their feet or work on hard surfaces, such as janitors, road construction workers, carpet layers have an increased risk of OA.
What is scoliosis?
abnormal curvature of the spine usually in the lateral direction
What are the top musculoskeletal injuries by body part?
back -46%, shoulder -14.4%, arms -4.4%, wrists -6.5%, knee -5.9%, neck -1.6%
What is hyperlordosis?
excessive development of a forward curve in the lumbar spine.
How is Tinel's test performed?
performed by tapping the median nerve at the wrist. Tapping a compressed median nerve induces tingling in one or more fingers in the hand afflicted with CTS.
What is Tension neck syndrome?
static trapezius contraction in precision work
Do females or males report more back pain?
• Females report slightly more back pain in terms of work limitation, compared to males
What can cause lumbar lordosis?
•An increased lumbosacral angle may result in exaggerated lumbar lordosis (swayback)
What were ganglion cysts also called?
"Bible bumps" because the bible was used to pound and rupture the cyst.
What is a strain?
- A muscle, ligament, or tendon insertion is strained when it is pulled or pushed to its extreme. By forcing the joint beyond its normal range of motion. - results from lifting a heavy object or holding against an external force.
What is thoracic outlet syndrome caused by?
- Caused by hypertrophy of the subclavius or pectoral muscles due to repetitive shoulder abduction and adduction. - Associated with overhead work, reaching above shoulder level.
How can workplace redesign prevent CTDs?
- Correct working posture by adjusting the workstation to the height of the worker -manual crank or power lift: •Elimination of extended reaches •Avoid work-surfaces that cause friction or rubbing on any body part •Avoid excessive wrist deviation •Hands, wrists, and forearms should be able to move straight out from the body •Keep elbows close to the body •Tilt part bins, boxes to avoid bending the wrists or back 63 HSCI 580, Occupational Ergonomics, •Adjust the work surface toward the body to bring the work into easier reach -careful on this one if parts slide toward you then can cause a problem too. •Provide armrests to support the forearms and give relief to the shoulders and neck muscles •Store parts of containers designed and situated within the worker's reach to minimize hand flexion and extension
What is an unsheathed tendons?
- Found in the elbow and shoulder joints. - when strained or subjected to overuse, the tendons become irritated and radiate pain from the elbow down to the forearm.
What are engineering solutions to prevent CTDs?
- Job Redesign (eliminate repetitive tasks performed in awkward postures); - Enlarge tasks requiring different movements; - Design fast-paced tasks with work cycles longer than 30 seconds; - Avoid keeping the same posture; - Minimize pinch grips -use whole hand; - Hold an object near to the center of gravity for better balance; - Provide flanged support on handles; - Avoid excessive forces; - Minimize exposure to vibration and cold temperatures; - Automate repetitive tasks when technologically and economically feasible.
What are differences between Raynaud's disease and phenomenon?
- Symptoms due to other underlying disease in phenomenon - laboratory evaluation abnormal in phenomenon - Angiography (assessment of blood and lymph nodes) see structural changes in phenomenon - tropic changes (necrosis, atrophy) is common in phenomenon
What is a ganglionic cyst?
- another form of a tendon sheath disorder - affected sheath swells up with synovial fluid and causes a bump under the skin, often on the wrist.
What is Osteoarthritis?
- articular cartilage wears down -Common in the hands, knees, hips, spine
What is kyphosis?
- backward curvature of the thoracic spine - humpback appearance
What are awkward postures associated with CTDs in the neck and back?
- bending the neck downward - holding the chin forward - bending the back forward to reach an object
What are back injuries associated with CTDs?
- chronic lumbar strain - herniated intervertebral disk by sudden jury movement, extreme twisting, and/or strong push or pull - compression fracture of vertebrae - muscle spasm - scoliosis - unstable (dislocated) vertebrae - kyphosis - hyperlordosis
What is Knee osteoarthritis?
- inflammation in the knee accompanied by cartilage rigidity and atrophy - Bone spurs, cartilage wear and narrowed joint space also signs of knee OA.
What are the four general categories of occupational health problems?
- musculoskeletal disorders - cardiovascular disease - dermatologic disorders - other disorders
What causes carpal tunnel syndrome?
- overactive pituitary - hypothyroid - rheumatoid arthritis - fluid retention
What are awkward postures associated with CTDs in the shoulders?
- raising the upper arms above shoulder level - rotating the arms - holding the elbows away from the body
What are lowering, pulling, pushing, and carrying activities that can cause back injury?
- sudden or jerky movement to create inertia instead of smooth lifting - extreme twisting instead of pivoting - lifting objects too far away from body - lifting with the back flexed - using weak back muscles instead of the leg muscles which are stronger - reaching above shoulders especially when lifting an object - awkward workstation design - poor postures in sitting and standing - vertical vibrations such as those experienced by truck and bus drivers or construction machinery operators - accidents, including falling, slipping and tripping incidents - poor non-occupational postures in sitting and sleeping - large abdomen with weak muscles - weak muscles (especially back muscles) due to lack of exercise and stretching
What is trigger finger?
- tendons flexing finger. - Characterized by painful locking during flexion
What are awkward postures associated with CTDs in the hands and wrists?
- turning the palm of the hand upward (supination) - twisting the wrist - bending the wrist dorsally (extension) or palmarly (flexion), wrist adduction (bending ulnarly) and abduction (bending radially, towards the thumb), or pinch grip
What are good work practices that can prevent CTDs?
-Aligning the ears, shoulders, and hips -Aligning the elbows, wrists, and hands in neutral position -Elbows close to body -pone foot during standing on a footrest to reduce strain on the low back region
What are the effects of Cubital tunnel syndrome?
-Causes numbness & tingling in little finger & ulnar half of ring finger. -Usually accompanied by atrophy of intrinsic hand muscles and grip weakness -Resting on elbow or repetitive elbow flexing cause symptoms
What is the result of thoracic outlet syndrome?
-Compression of brachial plexus can result in numbness of the lower arm and hand -Impinged subclavian artery can result in ischemia and increase fatigue from static muscle contraction
What is the Thoracic outlet syndrome?
-Neurovascular disorder of the bundle carrying nerves, arteries, veins from the neck through the shoulder to the arm. - Symptoms include numbness & tingling of the arm and hand.
What are the effects of carpal tunnel syndrome?
-Results in motor impairment (grip weakness), sensory impairment (tingling, burning, prickly), autonomic impairment (diminished sweat). -Patients exhibit significantly increased pressure in carpal tunnel. •Flexion and extension movements increase the pressure
What are the types of Tenosynovitis?
-Trigger finger -De Quervain's syndrome:
What are good work habits that can prevent CTDs?
-Use whole hand grasps, avoid pinch grips -Hold object at its center of gravity for better balance -Adjust height of work surface with body height •Good tool use •Use tools with the right grip size (1" female, 1.5 male) •Right handle length (4" female, 5" male) •Handle should be angled not the wrist during work •Cushioned handles for better grip and reduced vibration •Keep tools in good repair, sharpen blades and bits for less muscular effort during use.
What is De Quervain's syndrome?
-abductor pollicislongus and extensor pollicisbrevis tendon sheaths - Can result in popping of tendons as wrist ulnar deviated and thumb flexed inside palm - "Blackberry thumb"
What is Medial epicondylitis ?
-golfer's elbow - tendinitis of forearm flexors •Resulting from forceful flexions and rotation of the forearm.
What are administrative controls that can prevent CTDs?
-revise work-rest schedules -more mini-breaks less longer breaks; rotate workers among jobs - -rotation within each day is preferred over rotation between days; -Training -raise awareness of CTD causes and how to prevent them. -Early communication of symptoms and an astute first line supervisor who has the authority to help the workers is one the best intervention solutions.
What is Supraspinatus tendinitis?
-rotator cuff syndrome - tendinitis of the muscle elevating the shoulder - Impingement of the bursa and supraspinatus tendon upon shoulder abduction.
What is Lateral epicondylitis?
-tennis elbow -tendinitis of forearm extensor and supinator muscles -Repeated wrist extensions or alternating pronation/supination of the wrist.
Which groups report the largest percentages of back cases with days away from work?
1) Service industry 2) manufacturing 3) retail
What are the two tests to diagnose carpal tunnel syndrome?
1) Tinel'sTest: 2) Phalen'sTest
What are the three stages of disc degeneration?
1) bulging disc 2) herniated disc 3) pressure on spinal nerves
How much of total injuries were due to repetitive motion, with an average of 24 days away from work?
3.2%
How much of low back pain is cause by excess lordosis?
3/4
How much of the 900,000+ injuries in 2010 were musculoskeletal related with an average of 11 days away from work?
30%
Where does Cubital tunnel syndrome occur?
: ulnar nerve at elbow.
Where does Guyon's canal syndrome occur?
: ulnar nerve at wrist
What causes a herniated disc?
As a disc degenerates due to injury, disease, or wear, the inner core extrudes back into the spinal canal, which is known as a disc herniation.
Why is the elbow particularly vulnerable to tendinitis?
Because of the imbalance between the large forearm muscles and the small insertion area of the epicondyle of the humerus bone (elbow).
How is Phalen's test performed?
In this test the patient is asked to put the backs of his/her two hands together and acutely flex his/her wrists for one minute. Development of tingling in the fingers is a positive sign of CTS.
What is neurogenic pain caused by?
Neurogenic pain may be caused by entrapped nerve, following sensory distribution
What causes a bulging disc?
Normal, everyday pressure on the disc forces its outer surface to budge slightly
What is Primary Raynaud's phenomenon?
bouts of white finger and painful sensations triggered by cold temperatures
Where are the symptoms of tennis elbow most common?
common on the outer side of the elbow.
What is carpal tunnel syndrome?
compression of the median nerve passing through carpal tunnel
What is Bursitis?
inflammation of synovial sacs in elbow, shoulder, knee, hip
What is Tenosynovitis?
inflammation of tendon sheath
What is tendinitis?
inflammation of the tendons
Where does radial tunnel syndrome affect?
lateral elbow
What is hip bursitis?
pain in outer part of upper thigh
What is a bursa?
small fluid-filled sacs located in major joints in the body
What is Patellofemoral pain syndrome caused by?
•Caused by overuse or misuse of the knee -More common in women
What are ways to prevent CTDs?
•Engineering Solutions •Workplace redesign •Administrative Controls •Good work practices •Good work habits • Personal Protective Equipment
What PPE would help prevent CTDs?
•Gloves -to reduce vibrations and to protect hands from extreme temperatures •Gloves should fit properly and be flexible for easier grapping of objects •Finger cots can be used to increase friction and to protect the fingertips from cuts •Fingerless, padded gloves to protect palms against impact and vibration but allow dexterity •Back-supports only help when the person has an injured back and it is prescribed by a qualified physician. No data to suggest that back supports (back belts) prevent healthy backs from getting injured. •Knee pads -good if workers have to kneel to do work (I.e., shipbuilding, carpet layers, construction, etc) •Wrist splints -don't even think about it -can harm workers if worn on the job -ok if used while sleeping to prevent "fetal posture" bending of wrists while sleeping.
What are the nerve disorders?
•Guyon'scanal syndrome •Cubital tunnel syndrome: •Radial tunnel syndrome: lateral elbow *Carpal tunnel syndrome: - Thoracic outlet syndrome
What are seven of the most Common Work Risk Factors for Developing CTDs?
•High Rates of Manual Repetition •Excessive Manual Force •Awkward Posture •Insufficient Recovery Time •Sustained Muscle Loading •Vibration •Temperature
What are non-occupational risk factors for CTDs?
•Hobbies with similar repetitive muscle patterns to the work tasks. •Biological and medical conditions such as wrist size, hormone levels, rheumatoid arthritis, diabetes, acromegaly •Non-Occupational factors contribute to work-related CTDs, but magnitude is unknown.
What are the main groups of tendinitis?
•Insertional tendinitis: tendon-bone interface •Peritendinitis: central region of the tendon •Myotendinitis: muscle-tendon junction
What is Patellofemoral pain syndrome?
•Irritation to underside of patella, where it meets the femur. •Pain associated with extended sitting, squatting, jumping, stair use (espdescending) •Knee may "give out", make popping noises or have a grinding feeling.
Who experiences patellofemoral pain syndrome?
•Manual laborers, such as carpenters, miners, report high levels of PFPS •People with desk jobs also report PFPS due to extended sitting
What are the risk factors for low back pain?
•Manual materials handling •Postural demands •Whole body vibration •Slipping and tripping: •Psychosocial factors:
