Osteoarthritis : Osteoarthritis Shahbaz Shafi Malik
BSc (Hons), MB BCh, MRCS
Norfolk & Norwich University Hospital OA : OA Chronic disorder
Degenerative joint disease
Result in progressive erosion of articular cartilage Epidemiology : Epidemiology Starts at 50 years of age
Female > male (2: 1)
10% of general population Classification : Classification Primary OA
Idiopathic and appears insidiously
arises without obvious predisposing influences
Genetic – familial tendency
Obesity – OA knee Slide 6: Secondary OA – presence of other predisposing factor
Intrarticular fracture, recurrentl dislocation
Congenital deformity of a joint
Perthe’s diease, SUFE
Underlying systemic diseases
DM, Haemochromatosis, Obesity Pathology : Pathology The cardinal features are:
Progressive loss of cartilage thickness
Subarticular cyst formation and sclerosis
Remodelling of the bone ends and osteophyte formation
Capsular fibrosis Pathogenesis : Pathogenesis The normal homeostasis in the joint is disturbed
OA is a disease of wear-and-tear :
Occurs in old age
Weight bearing joints
Increase frequency in the joints predisposed to abnormal mechanical stress obese & previous joint deformity
Risk increased with:
Reduced Bone density
High levels of oestrogen Pathogenesis : Pathogenesis Pathogenesis : Pathogenesis Characterized by significant changes of:
Mechanical properties of cartilage
Early the degenerating cartilage
Increased in water
Decreased concentration of proteoglycans
Weakening of collagen network (reduce type II collagen)
IL-1, TNF and NO are increased in the joint
Increased apoptosis of chondrocytes
These result in:
Reduce tensile strength
Reduce resilience Degeneration Morphology : Morphology Early stage:
Increased in chondrocytes
Subsequently cracking of the matrix
Small fractures & dislodge, producing ‘joint mice’
Osteophytes formation Clinical features : Clinical features Pain
Loss of function History : History Age - > 50 years
Occupation – what type?
Any history of trauma around the joint?
Secondary causes – congenital, RA
Any joint pain become worst by activity, relieved by rest.
Joint stiffness – early morning, long rest
Affect on daily activity !!
Climbing stairs Examination : Examination General examination
Muscle wasting (quadricep)
Palpable osteophytes Examination : Examination Movement
Valgus/varus stress Investigation: X-ray features : Investigation: X-ray features Narrowing or loss of joint space
1st sign of OA - reflects loss of articular cartilage; main pathology
Osteophyte formation-around the periphery of the joint.
Subchondral sclerosis-looks very white on the radiograph.
Subchondral cyst X-ray features : X-ray features Management - Conservative : Management - Conservative Pain relief
Analgesic and NSAIDS
To increase movement to prevent muscle wasting and deformity/contracture.
non -weight bearing exercise to strengthen muscle strength (cycling, swimming etc).
To reduce load on the joint
Weight loss if patient is obese
Use of walking stick to distribute the load
Avoid unnecessary stress,eg jogging,climbing stairs Operative management : Operative management Arthroscopic debridement and cleaning of the joint cavity and infusion of synthetic synovial fluid.
If stiffness is acceptable and neighbouring joints are not likely to be prejudiced. Usually done in young patient.
Joint replacement -usually done in old patient. OA - Knee : OA - Knee Knee is a complex synovial joint formed between femoral condyles, tibial condyles & patella.
Stabilised by variety of ligaments.
Active movement at the knee are:
medial rotation & lateral rotation. Articular Cartilage : Articular Cartilage Reduce friction at the joint
Act as a cushion to absorb the shock associated with joint use
Transmit weight loads to the underlying bone. Mechanical Axis : Mechanical Axis The mechanical axis of the knee is a line extending from the center of the hip joint to the middle of the ankle joint. This line is practically perpendicular to the ground.
In a healthy, well aligned knee joint, the mechanical axis passes through the middle of the knee.
Only when the mechanical axis passes through the center of the knee joint, the stresses on the knee joint surfaces are uniform in all areas of the joint and well balanced.
In many knee joint diseases, the mechanical axis is disturbed and does not pass through the center of the joint. This disturbance results in the overload of distinct areas of the knee joint leading to their damage. The patella lies not symmetrically in its groove. Mechanical Axis : Mechanical Axis Radiological exam : Radiological exam Views
Standing AP (weight bearing)/Lateral
Notch patellar views (Sunrise view)
Posteroanterior intracondylar (PAIC)
Joint space narrowing
Medial tibiofemoral joint space narrowing
Patellofemoral joint space narrowing
Lateral joint space narrowing to lesser extent
New subchondral bone formation
Tibia lateral subluxation
Medial osteophytes are most prominent initially Grading : Grading The best way to see if osteoarthritis is present and see the severity is by looking at x-rays of the knee. OA is classified into 5 stages :
Grade 0: · Normal knee joint · No loss of cartilage and no deformation
Grade 1: · Some loss of articular cartilage · If severe loss of cartilage, joint space narrows · Osteophytes may be seen Slide 29: Grade 2: · More activity in the bone under the cartilage · Increased activity can lead to bone hardening (sclerosis) and cysts · Change in bone density (whitening of bone on x-ray)
Grade 3: · Some deformations on edge of bone · Rough edges · Increased joint narrowing
Grade 4: · Complete loss of joint space · Definite deformity of bone ends · Changes in joint shape mean the bone contour has been altered Role of diacerein & glucosamine : Role of diacerein & glucosamine Diacerein is IL-1 inhibitor
Disease modifying effect on O.A.
Prophylactic use of diacerein leads to lower degree of articular stiffness when compared to glucosamine
Prophylactic chondroprotective effects of diacerein and glucosamine are histologicaly similar. Surgery : Surgery Arthroscopic debridement
Proximal tibial osteotomy
Distal femoral osteotomy
Chondral resurfacing procedure
Autologous chondrocyte grafting
UKA Arthoscopic techniques : Arthoscopic techniques Simple lavage
Abrasion chondroplasty OSTEOCHONDRAL & AUTOLOGOUS CHONDROCYTE TRANSPLANTATON : OSTEOCHONDRAL & AUTOLOGOUS CHONDROCYTE TRANSPLANTATON Healthy chondrocytes are harvested from an uninvolved area of injured knee.
Grown in tissue culture
Injected into knee cartilage defect.
Sealed over with a periosteal flap from proximal medial tibia
Still experimental Arthoplasty : Arthoplasty Preservation of bone stalk
Immedite wt. bearing
Shorter recovery time
Easier revision to TKR
Prosthesis loosening & failure TKR : TKR References : References 1.