Definition
Osteoarthritis (OA) is a degenerative joint disease, occurring primarily in older persons, characterized by erosion of the articular cartilage, hypertrophy of bone at the margins (i.e., osteophytes), subchondral sclerosis, and a range of biochemical and morphologic alterations of the synovial membrane and joint capsule.
Biomechanics of the knee
Knee joint composed of 3 bones (tibial, fibular and femur) and consist of 2 joint which are tibiofemoral joint and patellofemoral joint. The strength & stability knee joint depends on tendon and ligament (hip joint depend on a close fit between bone). The superior tibia and inferior femur are covered by articular cartilage (Ross & A.Simmons 2007) .
The articular cartilage consist of a layer of hyaline cartilage with cover the bone. The function is to reduce friction between bone during movement and absorb shock.
Causes of Osteoarthritis
- Repetitive ‘’microtrauma’’
- Repetitive knee bending
- Obesity
- Aging
Pathophysiology
When excessive mechanical stress happened, it causes structural fissures and erosion, damage and lost articular cartilage over the knee joint. Then, the surface becomes rough and worn. The tissue damage cause release enzymes that accelerate disintegration of cartilage on the bone over knee joint. Exposed and damage subchondral bone, cysts, osteophytes or new bone spurs develop around margin. The pieces of osteophytes and cartilage break off into synovial joint made the knee joint become narrowed.
SIGN AND SYMPTOMS OSTEOARTHRITIS
- Pain
- Bone enlargement
- Joint movement limited
- Crepitus
Typical characteristics of pain and clinical signs of osteoarthritis
- Pain: Age>45years (often >60), insidious onset over months or years, variable or intermittent over time, pain mainly related to movement and weight bearing, relieved by rest, only brief (<15mins) morning stiffness, usually only one or a few joints painful (not multiple regional pain).
The clinical sign:
- Restricted movement due to capsular thickening, or blocking by osteophyte
- Palpable, sometimes audible, coarse crepitus due to rough articular surface
- Bony swelling (osteophyte) around joint margins
- Deformity, usually without instability
- Joint-line or periarticular tenderness
- Muscle weakness, wasting
- No or only mild synovitis (effusion, increased warmth)
Complication
- Stability
- Fatigue
- Bone deformity
- Wrong posture
Doctor’s Management
- Diagnosis of OA is typically based on a medical history and physical examination
- X-ray
- Magnetic Resonance Imaging (MRI)
- Joint aspiration (procedure in which fluid is drained from the affected joints and examined)
- Blood test
Treatment for osteoarthritis
All the treatment goals are to improve joint function and quality of life, obtain pain relief, reduce joint inflammation, restore function and reduce disability.
1) Operative : Several surgical options:
- Arthroscopic debridement
- Realignment procedures (osteotomy)
- Joint fusion (arthrodesis),
- Joint replacement (arthroplasty)
- Partial knee replacement
- Total knee replacement (TKR)
2)Conservative – pharmacology and nonpharmacology.
NON-PHARMACOLOGICAL
- Exercise
- Dietary modification and weight reduction
- Physical therapy
- Ambulatory assistive device
- use cane on opposite side of affected extremities
- use appropriate shoes wear and bracing
e.g,: unloader knee braces
PHARMACOLOGICAL
- Begins with analgesics : e.g: acetaminophen (4g/day)
- Topical cream containing capsaicin: -for local relief
- NSAIDs: e.g : ibuprofen, ketoprofen, naproxen
- Intra-articular injection of corticosteroid or hyaluronic acid.
Physiotherapy management
GOALS & EXPECTED OUTCOME:
- Decrease pain
- Increase or maintain the ROM of all joint sufficient for functional activities
- Increase or maintain muscle strength sufficient for functional activities
- Increase joint stability & decrease biochemical stress on all affected joints
- Increase endurance for all functional activities
- Promote independence in all ADL, including bed mobility & transfer
- Improve efficiency & safety of gait pattern
- Establish patterns of adequate physical activity or exercise to maintain or improve musculoskeletal & cardiovascular fitness & general health
- Educate the patient, family & other personnel to promote the individual’s capacity for self-management
Physiotherapy Treatment
1) Pain relief
- TENS for knee OA : repeated use was more effective than a single application, use at least 4 weeks
- cryotherapy
- orthoses also may be used to alleviate pain, through biomechanical support or correction for knee OA pt.
- OA bracing – OA unloader for genu varus& genu valgus
2) Joint mobility
- include manual therapy & exercise
- restore normal osteokinematic & arthokinematic motion at knee & hip joint
- especially knee extension & hip rotation ROM
3) Stretching
-quadricep, hamstring, calf, & gluteal
- involve whole body training & working with breathing exercise such tai chi
3) Joint protection
- foot orthotic
4) Gait training
5)Strengthening
- for knee OA, LE exercise that functional training
-reduce pain & improve function
- quadriceps & gluteus
- include isometric, isotonic & functional exercise
6) Endurance training
- aerobic for cardiovascular fitness
- cycle ergometry or aquatic program can be used
- walking & stationary bicycles – safe & effective means of aerobic exercise
7) Functional training
- rearrangement the home or work environment
- eg. Raising beds or chairs can reduce the effort needed to stand-up
8)Patient education
9) ADL modifications
