OSTEOARTHRITIS

1. OSTEOARTHRITIS

2. Two Major Forms of Musculoskeletal Pain • Articular • Degenerative: Osteoarthritis (OA) • Inflammatory: Rheumatoid Arthritis (RA), etc., • Crystal-induced: Gout, CPPD • Other • Nonarticular • Fibromyalgia • Soft tissue trauma • Tendonitis, Bursitis, etc.

3. Arthritis Care: An Increasing Burden on Healthcare Resources Prevalence 49.8 (19.2) 50 40 28 (10.2) 30 Millions of Cases in US (% Population)* 15.8 (6.1) 20 2.1 (0.8) 10 0.6 (0.23) 0.3 (0.12) 0 Ankylosing spondylitis Other systemic connective- tissue disease Osteoarthritis Rheum. arthritis Soft-tissuedisease Osteoporosis† *Data for 1993/94 †NationalOsteoporosis Foundation. www.nof.org. Dec 6, 2000. The Arthritis Foundation Fact Book for the Media. Atlanta, Georgia. Arthritis Foundation; 1994:1–4.

4. Arthritis • 43 Million people in the US have some form of arthritis • 2020 it is expected that 103 million people will be effected • For approximately 3 million people in the US, the primary cause of limitation of movement is arthritis

5. Extent of Musculoskeletal Diseases in United States • 37.9 million people affected by arthritis • – 21 million with clinical signs and symptoms • of OA • – 2.1 million with RA • Data from 1990 • Lawrence et al. Arthritis Rheum. 1998;41:778–799. • 315 million physician visits/yr • 8 million hospital admissions/yr • 17 million people with activity limitation • 1.5 billion days of restricted activity/yr • Data from 1990–1992 • Yelin, Callahan. Arthritis Rheum. 1995;38:1351–1362.

6. Economic Impact of MusculoskeletalConditions in the United States Direct Costs 12% 12% Direct medical costs $ 72.3 billion* Indirect costs (lost wages) $ 77.1 billion Total costs $149.4 billion (2.5% of GNP) Physician 5% Hospital Other provider Drugs 20% Nursing home Administrative 46% Other 1% 4% *In 1992 dollars Data from Yelin, Callahan. Arthritis Rheum. 1995;38:1351–1362.

8. Osteoarthritis: AKA Degenerative Arthritis Osteoarthrosis Old Age Arthritis Degenerative Joint Disease Wear and Tear Arthritis DJD

9. Osteoarthritis • Definition Slowly progressive deterioration of a joint in which localized loss of cartilage occurs in association with subchondral sclerosis, osteophytosis, cyst formation, and synovial thickening

10. SOCIOECONOMIC IMPACT OF OA • Most common reason for physician visits in people >55 years of age • Lost and limited work days • Impaired leisure activities • Co-morbidity: Heart disease, depression, etc. • Cost = Billions

11. Normal vs OA Joint Normal knee Osteoarthritic knee Thickened capsule Capsule Cyst formation Sclerosis in subchondral bone Cartilage Fibrillated cartilage Synovium Synovial hypertrophy Osteophyte formation Bone

12. Presentation • Symptoms • Pain: worse during the day—with activity or after activity • Stiffness: Minimal in the morning (<30 min); gelling after inactivity • Range of motion: decreased • Signs • Crepitus • Swelling—variable effusions • Restricted movement • Bony enlargement • Joint instability

13. Location & Prevalence of OA 80 Men 60 DIP 40 Knee 20 Hip 0 Prevalence of OA (%) 20 40 60 80 80 Women DIP 60 Knee 40 Hip 20 0 20 40 80 60 Age (years)

14. Articular Cartilage • Integrity depends on a balance between degradation and synthesis of extra-cellular matrix constituents Homeostasis Degradation Synthesis

15. Pathogenesis of OA Biomechanical Chondrocytes • ­ Matrix degradation • Cytokines • Enzymes • N.oxide • ¯ Matrix synthesis • IGF-1 • TGF-b Genetic Loss of matrix integrity Metabolic OA IGF = insulin-like growth factor; TGF = transforming growth factor

16. Articular Cartilage • A specialized connective tissue “organ” with a highly ordered anatomic structure that is avascular and aneural • A sparse chondrocyte population is embedded in extra-cellular matrix composed predominantly of water, proteoglycans, and type II collagen • The mechanical properties of articular cartilage are attributable to the extra-cellular matrix

17. Normal Hyaline Cartilage

18. Cartilage Ultra-structure • Collagen fiber alignment assists distribution of forces • Chondrocyte morphology varies within the tissue

19. Cartilage Structure • Proteoglycans attach to hyaluronic acid via link protein to form an “aggregate” or aggrecan • Aggrecan interactions dampen compressive loads • Type II Collagen encapsulates aggrecan and distributes forces, providing tensile strength and resisting shear

20. Cartilage Structure

21. Osteoarthritis Biochemistry • Proteoglycan changes Decreased () total proteoglycan (PG) content  hyaluronic acid (HA) content  aggregate size and aggregation of proteoglycans • Collagen Changes Ultrastructural changes in collagen Increased water content • Chondrocyte response division to form “clusters” cellular hypertrophy

22. Osteoarthritis • Cytokines can promote degradation and inhibit synthesis of extra-cellular matrix constituents OA Degradation Synthesis

23. OA: Cartilage Changes

24. Osteoarthritic Cartilage

25. Radiographic Findings • Bony sclerosis • Joint space narrowing • Marginal osteophytes • Subchondral cysts • Malalignment

26. Osteoarthritis of hands

27. Osteoarthritis of Hands: X-rays

28. Osteoarthritis: Synovial Cyst

29. Osteoarthritis of the Knees

30. Osteoarthritis of the Knee Subchondral bone Femoral condyle Patella

31. OA of the Hip • Pain often is located deep in the groin and radiates to the thigh • Check ROM

32. Osteoarthritis Cervical Spine Narrowed Neural Foramina

33. Osteoarthritis Lumbar Spine

34. Diffuse Idiopathic Skeletal Hyperostosis (DISH)

40. EPIDEMIOLOGY OF OA • Most common form of chronic arthritis • 1:5 affected worldwide, increases with age • >50% require medical therapy for pain and disability

41. Risk Factors • Age • Female sex • Trauma • Obesity (micro-trauma) • Genetic or hereditary links • Neuromuscular dysfunction • Metabolic disorders

42. WEIGHT AND OA Degree of Obesity RR(95% CI) (Range of BMI) Males Females Normal (>20 to 25) 1.00 1.00 Overweight (>25 to 30) 1.69(1.03-2.80) 1.89(1.24-2.87) Obese (>30 to 35) 4.78(2.77-8.27) 3.87(2.63-5.68) Very Obese(>35) 4.45(1.77-11.18) 7.37(5.15-10.53) Am J Epidemiol 1988;128:179

43. Goals of Arthritis Therapy • Relieve pain/inflammation • Minimize risks of therapy • Retard disease progression • Provide patient education • Prevent work disability • Enhance quality of life and functional independence

44. Drug Therapy Options in Osteoarthritis • Analgesics • NSAIDs (Rx, OTC), COX-2 Inhibitors • Topical agents • Intra-articular glucocorticoids • Intra-articular hyaluronan • Investigational agents

45. American Pain SocietyTreatment of Chronic Pain in OA • Plus, as needed: • Nonpharmacologic interventions • Glucosamine • Tramadol • Adjunctives • Intra-articular hyaluronic acid • Surgical intervention • Mild pain • Little or no inflammation • Acetaminophen • Moderate to severe pain/inflammation • COX-2–specific inhibitor Continued pain? Yes Continued pain? Conduct GI risk-factor analysis • High risk • Nonselective NSAID plus PPI or misoprostol • Not high risk • Nonselective NSAID • Hyaluronic acid injection for knee pain • Glucocorticoid intra-articular injection for other joint pain Yes Continued pain? American Pain Society, 2002.

46. ACR Osteoarthritis Guidelines ACR Subcommittee on OA Guidelines. Arthritis Rheum 2000; 43: 1905-1915

47. ACR Osteoarthritis Guidelines Nonpharmacologic MeasuresCornerstone of Therapy ACR Subcommittee on OA Guidelines. Arthritis Rheum 2000; 43: 1905-1915

48. Patient education Personalized social support through telephone contact Aerobic exercise program Range-of-motion exercises Assistive devices for ambulation Appropriate footwear Bracing Joint protection and energy conservation Self-management programs Weight loss (if overweight) Physical therapy Muscle-strengthening exercises Patellar taping Lateral-wedge insoles Occupational therapy Assistive devices for activities of daily living Nonpharmacologic Modalities ACR Subcommittee on OA Guidelines. Arthritis Rheum 2000; 43: 1905-1915

49. Physical Therapy 6 Minute Walk WOMAC Deyle, et al., Ann. Int. Med. 2000: 132; 173-81

50. Acetaminophenfor the relief of mild-to-moderate joint pain ACR Osteoarthritis Guidelines Nonpharmacologic Measures ACR Subcommittee on OA Guidelines. Arthritis Rheum 2000; 43: 1905-1915