OsteoarthritisOsteoarthritis

(Degenerative (Degenerative arthritis/osteoarthrosis/hypertroparthritis/osteoarthrosis/hypertrop

hic arthritis)hic arthritis)

OsteoarthritisOsteoarthritis

Osteoarthritis is a non-inflammatory, Osteoarthritis is a non-inflammatory, degenerative condition of joints degenerative condition of joints Characterized by degeneration of Characterized by degeneration of articular cartilage and formation of articular cartilage and formation of new bone i.e. osteophytes.new bone i.e. osteophytes.

Common in weight-bearing joints Common in weight-bearing joints such as hip and knee.such as hip and knee.

Also seen in spine and hands.Also seen in spine and hands. Both male and females are affected.Both male and females are affected. But more common in older women But more common in older women

i.e. above 50 yrs,particularly in i.e. above 50 yrs,particularly in postmenopausal age.postmenopausal age.

Risk factors Obesity esp OA knee

Abnormal mechanical loading eg.meniscectomy, instability

Inherited type II collagen defects in premature polyarticular OA

Inheritance in nodal OA

Occupation eg farmers

Infection:Non-gonococcal septic arthritis

Hereditary

Poor posture

Injured joints

Ageing process in joint cartilage

Defective lubricating mechanism

Incompletely treated congenital dislocation of hip

Classification of OAClassification of OA

OA

Primary OA Secondary OA

Primary OAPrimary OA

More common than secondary OAMore common than secondary OA Cause –UnknownCause –Unknown Common-in elders where there is no Common-in elders where there is no

previous pathology.previous pathology. Its mainly due to wear and tear Its mainly due to wear and tear

changes occuring in old ages mainly changes occuring in old ages mainly in weight bearing joints.in weight bearing joints.

Secondary OASecondary OA

Due to a predisposing cause such as:Due to a predisposing cause such as:1.Injury to the joint1.Injury to the joint2.Previous infection2.Previous infection3.RA3.RA4.CDH4.CDH5.Deformity5.Deformity6.Obesity6.Obesity7.hyperthyriodism7.hyperthyriodism

Types of OATypes of OA

Nodal Generalised OANodal Generalised OA • • Crystal Associated OACrystal Associated OA • • OA of Premature OnsetOA of Premature Onset

Nodal Generalised OA

• • Heberden’s nodes

• • Bouchard’s nodes

• • CMC of thumb

• • Hallux

• valgus/rigidus

• • Knees & hips

• • Apophyseal joints

Crystal Associated OA

• Calcium pyrophosphate

• dihydrate occurs

• mainly in elderly

• women, and principally

• affects the knee

OA of Premature Onset

• • Previous meniscectomy

• • Haemochromatosis

PathologyPathology

OA is a degenerative condition OA is a degenerative condition primarily affecting the articular primarily affecting the articular cartilage. cartilage.

1.articular cartilage1.articular cartilage2.Bone2.Bone3.Synovial membrane3.Synovial membrane4.capsule4.capsule5.Ligament5.Ligament6.muscle6.muscle

Articular CartilageArticular Cartilage Cartilage is the 1Cartilage is the 1stst structure to be affected. structure to be affected. ErosionErosion occurs,often central & frequently in occurs,often central & frequently in

wt. bearing areas.wt. bearing areas. FibrillationFibrillation,which causes softening,splitting ,which causes softening,splitting

and fragmentation of the cartilage,occur in and fragmentation of the cartilage,occur in both wt. bearing & non-wt. bearing areas.both wt. bearing & non-wt. bearing areas.

Collagen fibresCollagen fibres split and there is split and there is disorganisation of the proteoglycon collagen disorganisation of the proteoglycon collagen relationship such as H2O is attracted into relationship such as H2O is attracted into cartilage, which causes futher softening and cartilage, which causes futher softening and flaking.these flakes of cartilage break off and flaking.these flakes of cartilage break off and may be impacted b/w the jt.surfaces causing may be impacted b/w the jt.surfaces causing locking and inflammation.locking and inflammation.

Right: Early OA with area of cartilage loss in the center.

Left: More advanced changes with extensive cartilage loss and exposed underlying bone

Arthroscopic appearances in OA of the knee joint: fibrillated surface of the cartilage on the medial femoral condyle

Bone(Eburnation)Bone(Eburnation)

Bone surface become hard & Bone surface become hard & polished as there is loss of protection polished as there is loss of protection from the cartilage.from the cartilage.

Cystic cavities form in the Cystic cavities form in the subchondral bone because subchondral bone because eburnated bone is brittle and eburnated bone is brittle and microfractures occur.microfractures occur.

Venous congestion in the Venous congestion in the subchondral bone.subchondral bone.

Gross superior view of a femoral head from a patient with radiographic stage I OA. This shows an area of complete cartilage loss, with polishing or eburnation of the underlying bone.

Osteophytes form at the margin of Osteophytes form at the margin of the articular surface,which may get the articular surface,which may get projected into the jt. Or into capsule projected into the jt. Or into capsule & ligament,bone of the wt.-bearing jt.& ligament,bone of the wt.-bearing jt.

There is alteration in the shape of the There is alteration in the shape of the femoral head which becomes flat and femoral head which becomes flat and mushroom shaped.mushroom shaped.

Tibial condyles become flatened.Tibial condyles become flatened.

Osteophyte at margin of articular surface

Synovial MembraneSynovial Membrane

Synovial membrane undergo hypertrophy Synovial membrane undergo hypertrophy and become oedematous (and become oedematous (which can lead to which can lead to ‘cold’ effusions)‘cold’ effusions)..

Reduction of synovial fluid secretion results Reduction of synovial fluid secretion results in loss of nutrition and lubricating action of in loss of nutrition and lubricating action of articular cartilage.articular cartilage.

CapsuleCapsuleIt undergoes fibrous degeneration and there It undergoes fibrous degeneration and there

are low-grade chronic inflammatory changesare low-grade chronic inflammatory changes

LigamentLigament Undergoes fibrous degernationUndergoes fibrous degernation There is low grade chronic There is low grade chronic

inflammatory changes and acc.to the inflammatory changes and acc.to the aspect joint become contracted or aspect joint become contracted or elongated.elongated.

MusclesMuscles

Undergoes atrophy,as pt. is not able to Undergoes atrophy,as pt. is not able to use the jt. Because of pain which use the jt. Because of pain which further limits movts. and function. further limits movts. and function.

Clinical features of OAClinical features of OA

PainPain StiffnessStiffness Muscle spasmMuscle spasm Restricted movementRestricted movement DeformityDeformity Muscle weakness or wastingMuscle weakness or wasting Joint enlargement and instabilityJoint enlargement and instability CrepitusCrepitus • • Joint Joint EffusionEffusion

Clinical features 1• 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

Clinical features • Pain and tenderness (cont)

– Types of pain

• Mechanical: increases with use of the joint

• Inflammatory phases

• Rest pain later on in 50%

• Night pain in 30% later on

Clinical features 2• Movement abnormalities

– ‘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.

Clinical features 3

• Deformities– Soft tissue swelling:

• mild synovitis • small effusions

– Osteophytes– Joint laxity– Asymmetrical joint destruction leading to

angulation

Osteoarthritis of the DIP joints. This patient has the typical clinical findings of advanced OA of the DIP joints, including large firm swellings (Heberden’s nodes), some of which are tender and red due to associated inflammation of the periarticular tissues as well as the joint.

Knee joint effusion

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.

Pseudolaxity due to cartilage loss. The joint is not loaded in the first photograph

Unstable distal interphalangeal joints in OA. The examiner is able to push the joint from side to side due to gross instability, a common finding in late interphalangeal joint OA.

Radiographic Classification

Stage 1 Bony spur only

Stage 2 Narrowing of jt. Space,less than half of the normal jt. space

Stage 3 Narrowing of jt. Space,more than half of the normal jt. space

Stage 4 Obliteration of jt. space

Stage 5 Subluxation or sec.lateral arthrosis

Distribution of OA of the hip joint. OA can maximally affect the superior pole, inferior pole, posterior part or other segments of the hip joint. Superior pole involvement, with a tendency for the head of the femur to sublux superolaterally, is the commonest pattern. Involvement of the whole joint (concentric OA) is relatively uncommon.

Special Investigations

• Blood tests: Normal

• Radiological features:– Cartilage loss– Subchondral sclerosis– Cysts– Osteophytes

Management

Treatment Principles

• Education

• Physiotherapy– Exercise program– Pain relief modalities

• Aids and appliances

• Medical Treatment

• Surgical Treatment

Education

• Nonsystemic nature of disease

• Prevent overloading of joint. Obesity!!

• Appropriate use of treatment modalities– Importance of exercise program– Aids, apliances, braces– Medial treatments– Surgical treatments

Exercise

• Will not ‘wear the joint out’

• Important for cartilage nutrition

• Some evidence that lack of exercise leads to progression of OA

Exercise

• Encourage full range low impact movements eg swimming, cycling

• Avoid– Prolonged loading– Activities that cause pain– Contact sports– High impact sports eg running

Quadriceps exercises for knee OA. Quadriceps exercises are of proven value for pain relief and improving function, and everyone with knee OA should be taught the correct techniques and encouraged to make these exercises a lifetime habit. There is a weight on the ankle.

Use of transcutaneous nerve stimulation (TENS) as an adjunct to other therapy for pain relief at the knee joint. The use of acupuncture, TENS and other local techniques to aid pain relief in difficult cases of OA is often worthwhile.

Aids and appliances

• Braces / splints

• Special shoes/insoles

• Mobility aids

• Aids: dressing, reaching, tap openers, kitchen aids

• Taping of patella in patello femoral OA

Use of a cane, stick or other walking aid. This patient, who has hip OA, has found that she can reduce the pain in her damaged left hip by leaning on the stick in the right hand as she walks. The reduction in loading can be huge, and the effect on symptoms and confidence with walking very beneficial.

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.

Medical Treatment

• Simple analgesics: paracetamol, low dose ibuprofen

• NSAID’s/Coxibs PRN regular

• Intra-articular corticosteroids

• Topical treatment eg NSAID creams, capsaicin

• ‘Chondroprotective agents’

A patient with OA of the carpometacarpal joint of the left thumb undergoing arthrocentesis for injection of a depot corticosteroid preparation. The operator is distracting the patient’s thumb to open up the joint space.

Joint replacement surgery

• Indications: pain affecting work, sleep, walking and leisure activities

• Complications– sepsis– loosening– lifespan of materials (mechanical failure)