Work Related MSK Disorders Flashcards
What is a work related musculoskeletal disorder?
Diseases related to and/or aggravated by work can affect the upper limb extremities, the lower back area and the lower limbs.
A group of disorders, not a diagnosis
What are WMSDs defined by?
Impairments of body structures such as muscles, joints, tendons, ligaments, nerves, bones and the localized blood circulation system, caused or aggravated primarily by work itself or by the work environment
What are the primary reasons WMSDs occur?
Sprains, strains, bodily motions, overexertion, low back
other leading sources of injury: structures (walkways, floors, buildings), building materials, furniture, containers
What are the mechanisms of a WMSD?
Repeated microtrauma at the cellular level
What is at risk for WMSDs
Physical: muscles, joints, tendons, blood vessels, and nerves are at risk for the MSK disorders
Environmental: (still part of physical), cold environments, vibrations
How are cold environments a risk factor for WMSDs
Compromise muscle efficiency and may cause vascular and neurological damage
May require gloves that have been shown to impact sensations, thus leading to additional force exertion
How are vibrations a risk factor for WMSDs
Whole body vibration - mechanical energy oscillations that are transferred to the body as a whole - 4hz = low back, GI issues
Hand-arm vibration (HAV) - manual work involving vibrating power hand tools
What are individual risk factors to WMDSs
Age, sex, strength, anthropometry, smoking, training,
How is age a risk factor to wmsds
MSK impairments (specifically the back) are most prevalent in middle-older aged workers
Decreases in MSK function due to age-related disorders, loss of muscle fiber and of tissue strength with age may degradation increase the likelihood and severity of soft tissue damage
How is sex a risk factor for WMSDs
Women are three times more likely to have CTS than men (Women.gov, 2011).
Other reasons for the increased presence of WMSDs in women may be attributed to differences in muscular strength and anthropometry.
How is strength a risk factor for WMSDs
Relationship between back injury and weak back strength in job tasks
found a substantial increase in back injury rates in subjects performing jobs requiring strength that was greater or equal to their isometric strength-test values.
Risk three times greater in weak subjects
How is anthropometry a risk factor for WMSDs
Weight, height, body mass index, and obesity have all been identified in studies as potential risk actors
The risk for CTS among obese women was double that of thinner women
How is training a risk factor for WMSDs
An important part of a successful ergonomic program is training.
The training of employees is essential and should include training employees:
When the job is identified as a hazard
When an employee is assigned to a problem job - The best time!
Periodically, at least every 3 years
What structures are impacted by WMSDs
Muscle, tendons, nerves, vascular comprerssions
How are muscles impacted by Wmsds
obstruction of blood or nerve supply to the muscle can lead to complete deterioration of the muscle, muscle cramps, DOMS, tension stress, strains
How are tendons impacted by WMSDs
- collagen fibres do not stretch or contract
- development of scare tissue make the tendon more prone to repeated injuries and chronic tension
- surfaces can become rougher
- inflammation can occur if there is not enough synovial fluid in sheath
How are nerves affected by WMSDs
problem areas include = tunnels, branches, fixed, close to unyielding surfaces
nerve compression if the body part decreases the size of the opening through which the nerve runs
Hard surfaces and sharp edges of environment and tools can trigger nerve compression
How is vascular compression affected by WMSDs
Occurs when there is a constriction or obstruction of the blood flow supply
Vascular compression can result in ischemia which affects:
Duration of muscular activities
Recovery time of a fatigued muscle
Vasospasms may also occur from vibrations in certain body parts, particularly in the hands and fingers.
What is carpal tunnel syndrome (CTS)
- the median nerve is compressed when passing through the bony carpal tunnel
- associated with forceful and repetitive work
- An increase in pressure in the carpal tunnel can cause CTS if it affects the median nerve or reduces blood supply by compressing capillaries
- Symptoms include; pain, numbness tingling, burning sensations and the base of the thumb
What is tendonitis?
- highly repetitive movements are required, increase in blood supply to muscles is associated with decreased blood supply to the tendon
- Tendinitis can result from trauma or excessive use of a joint and can afflict the wrist, elbow, and shoulder joints.
What is lateral epicondylitis (tennis elbow)
Risk of injury is increased by activities requiring large or prolonged grasping forces
Combined stressors
Office settings (#2)
Construction
What is tenosynovitis?
repetition induced tendon injury that involves swelling of the tendons sheath
What is De Quervains Syndrome?
the most common type of tenosynovitis
Occurs in hand-intensive workplaces
Symptoms: pain, tingling, swelling, numbness, and discomfort when moving the thumb
Characterized by pain on the thumb side of the wrist and impaired thumb function
Activities requiring extensive thumb use are associated with this disorder
Avoidance of ulnar deviation when operation tools is indicated
What is intersection syndrome?
A type of tenosynovitis that remains on the forearm
Has the same causes as De Quervains