Musculoskeletal Disorders

Musculoskeletal Disorders (MSDs)

Musculoskeletal Disorders (MSDs) are injuries or disorders of the muscles, tendons, joints, nerves, ligaments, and vertebral discs. When these tissues are stressed on a regular basis without adequate time for recovery, they can eventually become damaged and lead to the development of MSDs.

Signs

  • can be physically observed, felt or heard
  • Redness, swelling, reduced range of motion, loss of strength, etc.

Symptoms

  • cannot be seen but can be felt by the individual
  • Pain, discomfort, aching, numbness, tingling, burning sensation, stiffness, fatigue, etc.

Mild

Back showing minor stage

Beginning of physical discomfort such as light pain.

Symptoms:  Pain, aching, fatigue

Onset: Weeks or Months

Job Performance: Not affected

Visible Signs: None

Treatment:  May be reversible if treated early

.

Moderate

Back showing moderate stage

Increased physical discomfort such as more frequent and intense pain.

Symptoms: Pain, aching, fatigue, sleep difficulty

Onset:  Months

Job Performance:  Decreased

Visible Signs:  May be present

Treatment:  Difficult and slower recovery

Severe

Back showing severe stage

Persistent physical discomfort such as intense and prolonged pain.

Symptoms: Constant to intense pain, fatigue, sleep difficulty

Onset: Months to years

Job Performance: Unable to perform job duties

Visible Signs: Often present

Treatment: Greater risk of permanent damage

Specific Musculoskeletal Disorders (MSDs)

Signs and Symptoms

When a muscle, tendon, nerve, or joint is stressed and traumatized on a repeated basis for days, months or years, those body tissues eventually become damaged. This leads to a work-related musculoskeletal disorder (MSD).

Work-related musculoskeletal disorders, sometimes referred to as repetitive strain injuries (RSI), are caused by increased trauma to an area and and overuse to injuries.

When a MSD develops a worker experiences:

  • Swelling (as tissues become more and more irritated)
  • Pain and Discomfort
  • Stiffness and Range-of-Motion Loss
  • Inability to Perform Functions and Duties (both at work and at home)

Hazards that cause musculoskeletal disorders include:

  • Awkward Postures
  • Static Postures
  • Force
  • Repetitive Movements
  • Vibration

Body Map

Ergonomic Risk Factors

Awkward Postures

  • Postures that deviate from neutral (e.g. reaching, twisting, bending, etc.)
  • kneeling
  • working with arms above shoulder level

Static Postures

  • Any posture that is held for an extended time

Force

  • Forceful exertions (i.e. lifting,
    carrying, gripping, etc.) 
  • Contact stress 
  • Mechanical stress 

Inadequate Recovery Time

  • Similar muscle actions performed multiple times in a short period 
  • Sustained muscle contractions without enough rest  
  • May lead to fatigue, weakness or altered movement patterns

Vibration

vibration
  • Mechanical oscillations of any frequency that are transferred to the body – may affect the entire body or individual body segments

Temperature

  • Working in hot or cold conditions

Contact Stress

  • External pressure that is applied to a part of the body for a sustained period

Psychosocial

  • The combination and effect of nonphysical aspects (social, cultural, and environmental influences) on the mind and behavior

Combination Effect

  • Many or all of the risk factors act in synergy

Repetition

ergoIcon_repitition
  • Short cycle time or fast paced work
  • Inadequate recovery time
  • Sustained or static postures(i.e. standing)