Work Related MSK Disorders

Question 1

What is a work related musculoskeletal disorder?

Answer 1

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

Question 2

What are WMSDs defined by?

Answer 2

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

Question 3

What are the primary reasons WMSDs occur?

Answer 3

Sprains, strains, bodily motions, overexertion, low back

other leading sources of injury: structures (walkways, floors, buildings), building materials, furniture, containers

Question 4

What are the mechanisms of a WMSD?

Answer 4

Repeated microtrauma at the cellular level

Question 5

What is at risk for WMSDs

Answer 5

Physical: muscles, joints, tendons, blood vessels, and nerves are at risk for the MSK disorders

Environmental: (still part of physical), cold environments, vibrations

Question 6

How are cold environments a risk factor for WMSDs

Answer 6

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

Question 7

How are vibrations a risk factor for WMSDs

Answer 7

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

Question 8

What are individual risk factors to WMDSs

Answer 8

Age, sex, strength, anthropometry, smoking, training,

Question 9

How is age a risk factor to wmsds

Answer 9

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

Question 10

How is sex a risk factor for WMSDs

Answer 10

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.

Question 11

How is strength a risk factor for WMSDs

Answer 11

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

Question 12

How is anthropometry a risk factor for WMSDs

Answer 12

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

Question 13

How is training a risk factor for WMSDs

Answer 13

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

Question 14

What structures are impacted by WMSDs

Answer 14

Muscle, tendons, nerves, vascular comprerssions

Question 15

How are muscles impacted by Wmsds

Answer 15

obstruction of blood or nerve supply to the muscle can lead to complete deterioration of the muscle, muscle cramps, DOMS, tension stress, strains

Question 16

How are tendons impacted by WMSDs

Answer 16

• 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

Question 17

How are nerves affected by WMSDs

Answer 17

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

Question 18

How is vascular compression affected by WMSDs

Answer 18

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.

Question 19

What is carpal tunnel syndrome (CTS)

Answer 19

• 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

Question 20

What is tendonitis?

Answer 20

• 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.

Question 21

What is lateral epicondylitis (tennis elbow)

Answer 21

Risk of injury is increased by activities requiring large or prolonged grasping forces
Combined stressors
Office settings (#2)
Construction

Question 22

What is tenosynovitis?

Answer 22

repetition induced tendon injury that involves swelling of the tendons sheath

Question 23

What is De Quervains Syndrome?

Answer 23

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

Question 24

What is intersection syndrome?

Answer 24

A type of tenosynovitis that remains on the forearm

Has the same causes as De Quervains

Question 25

What is a trigger finger?

Answer 25

Occurs in individual or multiple fingers and results when the tendons thicken or sheath swells

The finger then gets stuck in a flexed position

Question 26

What is ischemia?

Answer 26

Blood supply to the tissue is lacking

Common cause: compressive force in the palm of the hand

Excessive gripping
Numbness, tingling, could be some level of fatigue depending where it occurs

Question 27

What is hand-arm vibration syndromes

Answer 27

Vibration syndrome is often referred to as white finger, dead finger, or Raynaud’s disease.
Excessive exposure to vibrating forces(<500Hz) and cold temperatures may lead to the development of these disorders

Raynaud Disease:
Affects blood vessels and nerves of hands or feet
If detected early it can proceed, if not there can be permanent damage

Question 28

What is thoracic outlet syndrome?

Answer 28

• compression of nerves (brachial plexus) and/or vessels (subclavian artery and vein) to the upper limb
• Symptoms: aching pain in the shoulder of the arm, heaviness of easy fatiguability of the arm, numbness/tingling of the outside of the arm, swelling of the hand, finger stiffness
• Work activities such as
  carrying heavy shoulder loads
  pulling shoulders back and down
  reaching above shoulder level

Contributors: Weak shoulder muscles, long necks and sloped shoulders, poor posture and obesity may contribute to thoracic outlet syndrome.

Question 29

What is stage 1 of WMSD?

Answer 29

Eary stage
- momentary aches and tiredness during normal work hours
- symptoms go away overnight or on days off
- work performance not affected, symptoms can continue for weeks or months

Question 30

What is stage 2 of WMSD

Answer 30

Intermediate
- begin in the early work shift and do not go away overnight
- more chronic
- symptoms: tenderness, swelling, weakness, numbness, and pain.
- difficulty sleeping
- reduction in work performance (specifically repetitive work)
- symptoms last months

Question 31

What is stage three of WMSD

Answer 31

Late
- symptoms persist even at rest
- sleep is disturbed, pain is felt even with non-repetitive motions
- work performance highly affected, even when performing light tasks in dailylife
- lasts months or years

Question 32

How are WMSDs treated?

Answer 32

Restriction of movement
Adjust working postures/workspace
Application of heat or cold
Exercise/rehabilitation
Medication
Short-term fix
Try to avoid esp for long term
Surgery

Question 33

How can we tell if a job may cause WMSDs?

Answer 33

RULA, REBA, JSI, WISHA, NIOSH
Still consider the cold environment and vibration because they are not included in these assessments ^^