Conditions & Treatments - Knee Osteoarthritis

Knee osteoarthritis is the most common form of arthritis in the geriatric population (1, 2). Thirty-three percent of persons 63-94 years of age are affected by knee osteoarthritis (1, 2). Pain, impaired mobility, and reduced muscle strength are common findings in patients with OA which can limit activities of daily living (1, 2). Knee osteoarthritis is primarily characterized by cartilage deterioration along with associated ligament tearing, bone calcification and changes in musculature that may cause joint space narrowing (2, 3). Changes to the joint space can cause significant pain, muscle weakness, joint instability and decreased range of motion for these patients (3).

Risk factors for OA include (4):
1. Noted-trauma, immobilization
2. History of joint infection
3. Hemarthrosis
4. High intensity activities marked by repetitive impact and twisting – football, soccer, hockey, running, and etc.
5. Occupational Duties- repetitive heavy lifting, kneeling and squatting
6. Muscle weakness, obesity, genetics, nutrition and joint laxity

The first line of defense for OA includes weight loss, physical therapy, and exercise. The second line of defense includes surgery and pharmacologic intervention (5). Nonsteroidal anti-inflammatory drugs (NSAIDs) are shown to benefit patients, but are associated with major side effects including gastrointestinal complications, kidney damage, and potential fatality (5, 6, 7). Acetaphetamine may also be prescribed to patients since it has less serious side effects, but it is not as effective as NSAIDs (5, 6, 7). Arthroscopic surgeries, knee capsule injections of saline, and tidal irrigation have not been shown to have lasting proven benefits for the patients (1, 5). Exercise, however, has been shown to be the most effective intervention in reducing pain and functional limitation (1). Given the number of obese patients and geriatric patients that have limitations to exercise; a health professional such as a physical therapist is even more further indicated.

Common signs and symptoms of osteoarthritis consist of (4):
1. Onset of symptoms insidiously and progresses slowly
2. Deep ache
3. Aggravation with weight bearing or use of joint
4. Alleviation with rest, decreased weight bearing
5. Mild joint edema
6. Loss of flexibility/mobility/ROM
7. Crepitus with joint motion
8. Palpable osteophytes/bone spurs

Studies have shown that patients can benefit from manual therapy techniques used in combination with joint mobility and strengthening exercise by physical therapists (1,5). Manual therapy can be used for the improvement of elasticity of the joint capsule and the surrounding muscles and strengthening exercises can provide increased stabilization and decreased loading at joint surfaces. The manual therapy treatment techniques, consisting of passive physiologic and accessory joint movements, muscle stretching, soft tissue mobilization are applied to mainly knee joint, and strengthening of hip flexors and extensors, and knee flexors and extensors are typically performed (1,5). Studies found improvements in range of motion (11%), pain (33%), and gait speed (11%) after manual therapy and strengthening exercise (8).

Knee Osteoarthritis Treatment Options for a PT
• Gait Training
• Postural/Functional Training
• ROM exercises
• Stretching (see videos 28 & 30 for hip/groin/knee)
• Strengthening/Stabilization (see videos 17 & 21 for hip/groin/ knee)
• Manual Therapy
• Modalities

Last revised: June 9, 2011
by Minhwan Kim, SPT