Osteoarthritis knee

Knee Osteoarthritis and Management

1. Osteoarthritis Knee By: Dr Om Prakash Shah Professor Department of Orthopaedics Rohilkhand Medical College Bareilly(U.P.) Ex HOD Dr SN Medical College, Jodhpur(Rajasthan)

2. Definition Osteoarthritis is a non-inflammatory, degenerative condition of joints Characterized by degeneration of articular cartilage and formation of new bone i.e. osteophytes . It is one of the main joint of the lower limb, and for the routine daily activities of the person it is a very important joint.

3. Classification of OA

4. Primary OA More common than secondary OA Cause –Unknown Common-in elders where there is no previous pathology. Its mainly due to wear and tear changes occuring in old ages mainly in weight bearing joints. Secondary OA Due to a predisposing cause such as: 1.Injury to the joint 2.Previous infection 3.RA 4.CDH 5.Deformity 6.Obesity 7.hyperthyriodism

5. Epidemiology Knee OA most common cause of disability in adults Decreased work productivity, frequent sick days Highest medical expenses of all arthritis conditions Due to habit of sitting cross-legged and squatting OA is more prevalent in India. Symptomatic Knee OA More than 11% of persons > 64yr

6. Knee Anatomy The knee joint is formed by femur, tibia and patella.

7. Pathology OA is a degenerative condition primarily affecting the articular cartilage. 1. Articular cartilage 2. Bone 3. Synovial membrane 4. Capsule 5. Ligament 6. Muscle

8. Articular Cartilage- The lower end of the femur ( condyle of the femur) is covered by thick articular cartilage about 0.5-1 cm in thickness. Similarly, upper end of the tibia ( condyle of the tibia) is also covered by 0.5-1 cm thick articular cartilage. Articular cartilage is a smooth, shiny and elastic structure and it serves the function of a shock absorber. Cartilage is the 1 st structure to be affected. Erosion occurs,often central & frequently in wt. bearing areas. Right: Early OA with area of cartilage loss in the center . Left: More advanced changes with extensive cartilage loss and exposed underlying bone

9. Changes in Bone Bone surface become hard & polished as there is loss of protection from the cartilage. Cystic cavities form in the subchondral bone because eburnated bone is brittle and microfractures occur. Venous congestion in the subchondral bone. Osteophytes form at the margin of the articular surface,which may get projected into the jt. Or into capsule & ligament,bone of the wt.-bearing jt. Tibial condyles become flatened , medial tibial condyle is more affected and depressed as the weight bearing line passes medially. Thus, giving rise to varus deformity.

10. A patient with typical OA of the knees. In the normal standing posture there is a mild varus angulation of the knee joints due to symmetrical OA of the medial tibiofemoral compartments Knee joint Effusion

11. Synovial Membrane- Synovial membrane undergo hypertrophy and become oedematous ( which can lead to ‘cold’ effusions) . Reduction of synovial fluid secretion results in loss of nutrition and lubricating action of articular cartilage. Capsule It undergoes fibrous degeneration and there are low-grade chronic inflammatory changes.

12. Ligaments- Undergoes fibrous degernation There is low grade chronic inflammatory changes and acc.to the aspect joint become contracted or elongated. Muscles Undergoes atrophy,as pt. is not able to use the jt. Because of pain which further limits movts . and function.

13. Risk Factors Age (>45 yrs) Female (more common in post-menopausal women) Obesity ( most important modifiable) Previous knee injury (specially previous trauma and sports injury) Lower extremity malalignment Habit of squatting and sitting cross-legged High impact activities Muscle weakness Osteoporosis

14. Diagnosis of Knee OA Tests FBC, ESR, RF Arthrocentesis X-rays (3 views) Weight-bearing AP Lateral Tangential Patellar (Sunrise) MRI

15. Clinical symptoms Pain Joint Stiffness Swelling Crepitus Varus Deformity Synovial Thickening and effusion Synovial fluid WBC<2000/mm 3 Clear color High Viscosity X-rays Osteophytes Loss of joint space Subchondral sclerosis Subchondral cysts

16. Pain and Tenderness Usually slow onset of discomfort, with gradual and intermittent increase Pain is more on wt. bearing due to stress on the synovial membrane & later on due to bone surface,which r rich in nerve endings coming in contact. -Initially relieved by rest but later on disturb sleep. -Diffuse/ sharp and stabbing local pain Types of pain Mechanical: increases with use of the joint Inflammatory phases Rest pain later on in 50% Night pain in 30% later on

17. Joint Stiffness- ‘Gelling’: stiffness after periods of inactivity, passes over within minutes (approx 15min.) of using joint again Coarse crepitus : palpate/hear (due to flaked cartilage & eburnated bone ends) Reduced ROM: capsular thickening and bony changes in joint,ms . Spasm or soft tissue contracture.

18. Kellegren Lawrence Grading

19. Management Weight loss Nutrition referral Exercise Program (improves cartilage nutrition, muscle strength and prevents progression of OA and deformity) Physiotherapy Quadriceps strengthening ROM exercises Low impact activities e.g. swimming, biking Avoid high stress activities ( eg - jumping, running etc) Ambulatory assist devices Cane Walker Insoles Unloader knee braces

20. Medical Management Chondroprotective agents - Glucosamine/ Chondroitin /Collagen polypeptide/ Diacerin /Rosehip Powder (help in cartilage repair) Acetaminophen NSAIDs ( Diclofenac , Aceclofenac , Indomethacin , Nimesulide ) Cox-2 inhibitors ( Celecoxib , Etoricoxib ) Opioids ( Tramadol ) Intraarticular injections Glucocorticoids Hyaluronans Anti-Osteoporotic treatment( Bisphosphonates , Calcium, Vit D 3 ) Anti- Oxidants ( Vit A, C, E, Se, Mn , Zn)

21. Management: Algorithm Lifestyle Modifications Acetaminophen NSAIDs Opioids Celecoxib Steroid Injectio ns Hyaluronan Injections Surgical Referral

22. The use of shoes and insoles to reduce impact loading on lower limb joints. Modern sports shoes (‘trainers’) often have appropriate insoles. Alternatively, special heel or shoe insoles of sorbithane or viscoelastic materials can be used. They may help relieve pain as well as reducing the peak impact load on the joints during walking.

23. Surgical Management High Tibial Osteotomy Indication: Unicompartmental arthritis Genu varus or valgus Realign mechanical axis Age < 60yo < 15 degrees deformity 19

24. Partial Knee Arthroplasty Indication: Unicompartmental arthritis Ligaments spared Increased ROM Faster recovery Prosthesis 10-yr survival: 84%

25. Total Knee Arthroplasty Indication: Pain during rest is the strongest indication Diffuse arthritis Severe pain Functional impairment Pain relief > functional gain ACL sacrificed PCL also may be sacrificed Prosthesis 10-yr survival: 90%

26. Normal Knee Physiology Cartilage- S ponge like action (deformation and reformation) Beneficial for the joint function Facilitates blood supply of the joint Synovial Fluid- Lubrication of the joint and the articular cartilage (secreted by the synovial membrane around the joint) Smoothens the articular surface Healthy cartilage and good lubrication is necessary for smooth functioning and pain free movement of the joint Good mechanical axis is also necessary for smooth knee function

27. Protein Diet Multi-vitamins and multi- minerals Green vegetables Antioxidants, are necessary for repair of day to day wear and tear of the cartilage and maintainance of healthy cartilage

28. Effect of Pressure over Knee joint Pressure = Force/Area With every 1 kg loss of weight pressure over the knee joint will be decreased by 4 times the normal While walking pressure over the knee joint- 4-5 times the normal pressure While running pressure over the knee joint- 6-7 times the normal pressure While going uphill (climbing stairs) pressure over the knee joint is 7 times the normal Squatting and sitting cross-legged decreases the contact area between the joint surface so resulting in increase of pressure over the joint.

29. Effect of cane support in OA knee The cane will shift the centre of gravity during weight bearing forward to the body, thus decreasing the pressure over the knee joint by balancing the pelvis. There is about 20% decrease in the pressure over the knee joint. The stick should be held in the hand of the same side that of the affected knee. The length of the stick should be upto the greater trochanter of the femur from the ground and the elbow should be in 15 degree flexion. The handle of the cane should be straight and not curved.

30. Waddling Gait VIDEOS