Understanding Cumulative Trauma

1. Understanding Cumulative Trauma TM 655 Carter J. Kerk SDSMT Summer 2010

2. Assignment • Read MacLeod, Chapter Three

3. What is cumulative trauma? • Wear and tear on joints and surrounding tissues over time because of overuse • Cumulative vs. Acute • Low Back • Cervical Spine (neck) • Upper Extremities • Shoulder, elbow, wrist, fingers

4. Musculoskeletal & Neurovascular Disorders • Disorders of muscles, joints, tendons, ligaments, nerves, cartilage • usually a gradual buildup of stress to the musculoskeletal system and neurovascular system • diagnosis by a qualified medical expert • most common in upper extremities and spine

6. Disorder Terminology • Cumulative Trauma Disorders (CTDs) • Repeated Motion Disorders (RMIs) • Repetitive Strain Injuries (RSIs) • Musculoskeletal Disorders (MSDs) • Involving muscles and connective tissue • Connective Tissue (bone, cartilage, tendon, ligament, fascia) • Neurovascular Disorders (NVDs) • Involving nerves and blood vessels

7. MSD / NVD Symptoms • Vague, Slow to Develop • Soreness, pain, discomfort • Numbness, tingling sensations • Weakness, clumsiness • Burning sensations • Limited range of motion • Joint stiffness, popping/cracking in joints

8. Diagnosis • Difficult to diagnose • Proper diagnosis should only be done by a qualified medical professional • Certified Occupational Physician (Occ Doc) • By training, experience, examination in occupational illness/disease • A few specialists • Not most doctors, no nurses, no ergonomists, no physical therapists, no occupational therapists, no engineers, and certainly no managers, etc.

9. Treatment • Ice • Anti-inflammatory drugs • Rest • Possibly cortisone • After some time • Physical therapy (strengthening, stretching, work hardening, etc.) • Surgery (only as a last resort) • “Job Re-Design” – Always look at this

10. Early Recognition • Early recognition is important in controlling MSDs / NVDs • Use early warning systems (e.g. body discomfort surveys) • Training of employees and managers • Working relationship with Occ Doc • Stress “conservative treatment” • Non-surgical

11. The Risk Factor Model Lack of Rest Work/Rest Ratio Shift Length Environment Sustained Repetition Occupational Vibration Non-Occupational Temperature Posture Physical & Temporal Risk Factors Force Personal Psychosocial Compounding Risk Factors

12. Wrist Disorder Rates by Exertion & Repetition (n=574, Silverstein, 1985)

13. MSDs / NVDs Categorized by Body Part • Hand and Wrist • Elbow and Shoulder • Back, Neck, and Torso • Legs

14. Wrist • Bones • Ligaments • Tendons • Nerves • Carpal Tunnel

15. Elbow • Bones • Humerus (medial & lateral epicondyle); radius, ulna • Muscles • Forearm muscles attach at elbow • Nerves • Ulnar nerve

16. THE SHOULDER Anatomy • Bones • Muscles • Ligaments • Bursa • Cartilage

17. Hand and Wrist Disorders • Carpal Tunnel Syndrome (CTS), Tendonitis, De Quervain’s Disease, Digital Neuritis, Ganglion Cyst, Guyon Tunnel Syndrome, Synovitis, Trigger Finger

18. Elbow and Shoulder Disorders • Bursitis, Epicondylitis, Radial Tunnel Syndrome, Rotator Cuff Tendonitis, Thoracic Outlet Syndrome

19. Back, Neck, and Torso • Degenerative Disc Disease, Herniated Disc, Ligament Sprain, Mechanical Back Syndrome, Muscle Strain, Posture Strain, Tension Neck Syndrome, Hernia

20. Legs • Patellar Synovitis, Phlebitis, Plantar Fascitis, Shin Splints, Sub-Patellar Bursitis, Trochanteric Bursitis

21. Categories of Upper Extremity CTDs • Tendon disorders • Nerve disorders • Neurovascular disorders

22. Tendon Disorders • Tendonitis • tenosynovitis • De Quervain’s disease • stenosing tenosynovitis crepitans (trigger finger) • ganglionic cyst • lateral epicondylitis (tennis elbow) • medial epicondylitis (golfer’s elbow) • rotator cuff tendonitis

23. Nerve Disorders • Cubital tunnel syndrome • Carpal tunnel syndrome (CTS)

24. Neurovascular Disorders • Thoracic outlet syndrome • Vibration syndrome • white finger or Raynaud’s phenomenon

26. Swelling of tendons. Decreased blood supply to median nerve. Numbness/tingling in fingers. Prolonged irritation – scarring & nerve damage. Repetitive or strenuous activity. Carpal Tunnel Syndrome

27. DeQuervain’s Tenosynovitis • Swelling of tendon sheath that surrounds thumb tendons as they travel through the wrist to the thumb. • Overuse. • Strain injury. • Inflammatory arthritis.

28. Trigger Finger • Tendon thickens and bends finger • Arthritis, diabetes, lacerations, infections • Repeated “pistol gripping” of power tools • Long hours grasping steering wheel

30. Lateral Epicondylitis • Tennis Elbow • Chronic tendinosis of the wrist and finger extensors at their insertion at the elbow. • Tendons of forearm become irritated or tear away from medial or lateral epicondyle causing irritation. • Overuse of forearm muscles used for rotation of the arm and extension of wrist.

31. Medial Epicondylitis • aka. Golfer’s Elbow • Overuse of the flexor-pronator muscles whose origin is at anterior medial epicondyle of humerus • Sports related • Occupation related • Screwdriver, hammer use

32. Ulnar nerve entrapment • Muscle, ligament, & bone make up cubital tunnel. • Ulnar nerve travels medially. • Frequent elbow bending – pulling levers, reaching, lifting. • Repeated injury or pressure. • Resting elbow on hard surface for long periods. • Direct blow or injury to ulnar nerve. • Anatomy- nerve shifts, snaps over bone  irritation.

33. Rotator Cuff Injuries. • Single traumatic injury. • Collisions, fall on an outstretched hand • Multiple “micro-traumas” over time. • Repeated overhead activity. • Heavy lifting. • Normal degeneration in 3rd and 4th decades of life. • Most commonly the supraspinatus.

34. Impingment: Rotator Cuff Tendonitis or Shoulder Bursitis • Tendons become red, sore, & inflamed usually from crowding by surrounding structures. • Trapped under acromium(impingement) • Inflammation of the bursa usually occurs too. Causes – Overuse (frequent overhead reaching); Rheumatoid arthritis.

36. Low Back Pain (LBP) Categories • Muscular / Ligamentous • strain • Structural • overloading trauma, degenerative disease, facet dysfunction, osteoporosis, scoliosis • Discogenic • herniation, nerve irritation, tumor • Others • infections, congenital disorders

38. ? Magnitude and Trend: Numbers and types of occupational illness cases between 1972 and 2001. (DHHS 2004, Fig 1-22)

39. What are the reasons for the dramatic increase thru mid 90s? • Aren’t these the same jobs workers have been doing for decades? • Are workers getting weaker or wimpier? • Increased awareness and reporting? • Technological changes? • Aging workforce?

40. Increase in Awareness & Reporting • MSDs have probably existed since the Stone Age • Only recently have we begun recording • Increased media exposure • Proactive training • Work expectations (we may no longer be willing to accept the pain) • Employees realize they can receive compensation (for suffering or faking)

41. Increase in Awareness & Reporting (continued) • Diagnostic techniques have improved • Easier access to medical care and treatment • Companies are required by OSHA to record work-related disorders • When you start a new program, be prepared for a spike in reporting the first few years • Increased consciousness

42. Changes in Technology • Increase Specialization of Tasks • Typewriters to keyboard • Drafting tables to CAD software • Chicken at the grocery store • Increases in Assembly Line Work • Traditionally started in the automotive industry, now common in many sectors • Gaps in Automation • Highly automated processes may be interspersed with repetitive human tasks

43. Fads and Malingerers? • Fad? • “Australian Disease” (see course website) • Reporting phenomenon, increase attention in media • Ergonomics and CTDs are no fad! • Malingerers? • There is a problem – Workers’ Compensation • Malingerers are not the primary cause of increased claims

44. ? Magnitude and Trend: Numbers and types of occupational illness cases between 1972 and 2001. (DHHS 2004, Fig 1-22)

45. What are the reasons for the gentle decline since mid 90s? • Effects of ergonomics programs? • Effects of medical management? • Better overall understanding of the problem?

46. Were MSDs invented in the 1980s? • MSDs are Age-Old (read cases p. 76-78) • MSDs in the 1700s • Dr. Bernardino Ramazzini (founder of Occ Med) wrote a book in 1713 (Diseases of Workers) • But amidst all these disorders are descriptions of “. . . The harvest of diseases reaped by certain workers . . . from irregular motions in unnatural postures of the body.” • MSDs in Literature • Herman Melville’s Moby Dick (1851) about life he experienced on whaling ships: • “they have swelled their wrists with all day rowing” • “a roll of flannel for the small of someone’s rheumatic back” {i.e., a lumbar cushion}