Osteoarthritis What is new? Dr Peter Cheung, Rheumatologist, NUHS

Transcription

1 Osteoarthritis What is new? Dr Peter Cheung, Rheumatologist, NUHS

2 Objective Outline some clinical features that are not well appreciated in OA patients Recent advances in knowledge and management of OA Clarify some myths of OA

3 Case 1 50 year old lady works as a secretary of CEO, right handed Worsening pain in the PIP, DIP, and 1 st CMC joint in both hands for 12 months Worse in the right occasionally a bit painful in the morning and also after work Deformities in the DIP joints more apparent over the last 6 months Her mother also had similar problem O/E Heberden s and Bouchard s nodes, squaring of the 1 st CMC joint Dx: Hand OA

4 Hand osteoarthritis

5 Management Hand splints and OT Omega-3 Paracetamol Glucosamine and chondroitin sulphate NSAIDs Vitamin D?

6 Glucosamine + Chondroitin Theory: articular cartilage composed of proteoglycans, including glucosamine and chondroitins, and concentration reduced in OA?absorbed from GIT tract and to joint to reinforce articular cartilage and prevent further deterioration Down regulation of inflammatory mediators NF kappa B Efficacious for pain reduction (pharma sponsored) reduction in joint space loss (pharma sponsored) Large RCT showed neither glucosamine hydrochloride nor chondroitin sulfate improved either pain or function compared to celecoxib A 2 year follow up study found no protection against joint space loss

7 Potential protective actions of omega-3 in OA

8 Pharmacologic Measures Fish Oils ( Omega 3 fatty acids ) Reduce joint inflammation Glucosamine (1.5g) + fish oil (1332 mg fish oil and 600 mg omega-3) vs Glucosamine alone over ½year Higher reduction in pain, stiffness and increased functional ability in combination group Adv Ther (2009) 26(9):

9 Case 1 Progress Patient is worried about side effects of NSAIDs and does not want to take pain killers Decides to give omega 3 3g po daily and saw OT Worried about it being progressive

10 Myth: once joint pain is present with OA, progression is inevitable Joint pain intermittent and variable Damage of cartilage, then loss of cartilage, small or microscopic pieces of cartilage break off and float in the joint (fragments may cause pain) Removal of cartilage and natural breakdown leads to reduction in joint pain Synovitis resolves spontaneously or with injection Intermittent painful episodes can be treated symptomatically

11 Course of joint degeneration varies among patients with OA Many years elapse Cartilage has no nerve supply, inciting event may be asymptomatic Bone remodeling occurs with hypertrophy and changes in synovium with inflammation Articular cartilage and bone changes have occurred, symptomatic pain more consistent MRI- bone marrow lesions come and go and are associated with pain when present. Increased vascularity and cellular congestion caused by a lymphatic drainage system that is inadequate to clear the accumulated lymphatic fluid, increase fluid coming into the lesion increases the pressure?marker of progression

12 Pathogenesis Aneural cartilage = asymptomatic until innervated tissue affected = late dx Chondrocyte death and release of inflammatory mediators Synovitis = inflammatory OA Present in up to 90% (by MRI) Lancet 2011; 377: NYU Abramson OA research lab Subchondral bone inducing cartilage damage or vice versa?

13 And the next consultation, 3 months later She is better with less hand pain and aches Started to exercise, but walking up and down stairs was a problem, sit for too long knees stiff a bit swollen, worried she may have rheumatism! Right medial knee joint line pain with mild varus deformity X-Ray patellofemoral OA, and moderate OA She has decided running is bad for her

14 Pain that originates from patellofemoral joint is common and often accompanies tibiofemoral joint OA Degeneration of medial and lateral compartments results in significant amount of knee pain (either compartment is used a criteria for knee replacement OA in patellofemoral compartment worse with walking up an down stairs or inclines Patellofemoral pain worsen following prolonged sitting in movie theatre

15 Myth: OA is a disease of wear and tear Cartilage needs motion to maintain nutrition Weight bearing exercise improves blood flow to joints and allows fluid to process through synovium Facilitates lymphatic drainage that helps clear oxidative products Lack of joint motion leads to cartilage atrophy

16 Not disease, but symptom modifying Reduced pain & stiffness, improved function, mobility & psychological health Moderate treatment benefits with effect sizes of 0.40 for pain and 0.37 for physical function similar to those achieved from simple analgesia and NSAIDS Journal of Science and Medicine in Sport 14 (2011) 4 9

17 Case 2 45 year old diabetic lady with obstructive sleep apnea Pain in the shoulder right shoulder with reduced ROM Knee pain in right with swelling Groin pain in left O/E right frozen shoulder, right knee effusion with crepitus, pain on left hip internal rotation, pes planus and too many toes BMI=40 Dx: OA knee and hip, pes planus with tibialis posterior tendon dysfunction

18 Joint pain from hip OA is usually referred to the groin Pain with IR of hip felt in groin probably hip OA Lateral hip pain over trochanteric region during internal or external rotation is more likely gluteal medius enthesopathy Can also radiate to the anterior or lateral thigh, knee or lumbar spine

19 Factors contributing to OA progression in hips and knees can be modified Modifiable risk factors Weight loss how much? some studies suggested minimum of 5kg Depends on where one starts really Correction of leg length discrepancy through orthotics can reduce low back pain and improve joint function Modifying abnormal biomechanical forces across the knee from normal heel strike or pes planus through orthotics

20 Weight loss? 44 patients going for bariatric surgery BMI >50 Knee pain decreased after surgery (p<0.001) all WOMAC subscales were improved Levels of IL-6 (p<0.0001) hscrp (p<0.0001), Weight loss resulted in a significant increase: N-terminal propeptide of type IIA collagen levels (+32%; p=0.002), cartilage synthesis significant decrease in cartilage oligomeric matrix protein (COMP) (-36%; p<0.001), cartilage degradation Richette et al. ARD 2011

21 Intra-articular injections up to 4 x a year reduce joint pain and improve function Effective in treating OA flare in knee RCT rapid reductions in joint pain overall improvement in joint pain persisted through a follow up period of 14 days Can it accelerate cartilage progression? 2 year study showed no progression of radiographic damage with steroids every 3 months ACR recommends steroids not more than 4 times a year

22 Hyaluronic acid Hyaluronic acid is a component of synovial fluid and articular cartilage Joint loses much of the lubrication function of hyaluronic acid Alter synovial function, reduce the sensitivity of nerve endings increase endogenous production of hyaluronate and have a modest anti-inflammatory effect Knee pain not controlled by oral analgesics NSAIDs or intraarticular glucocorticoids All approved preparations show they are significantly more effective than placebo, 2/3 receive benefits (time for onset) Costly

23 Only primary OAs 3 year review Ann Rheum Dis 2010;69:

24 Summary Non-pharmacological Medical Vitamin D replaced? Paracetamol Glucosamine NSAIDs, contra-indicated can consider omega-3 Topical treatments Intra-articular treatments? Inflammatory OA refractory : can try hydroxychloroquine