The purpose of this study is to compare between therapeutic exercises and therapeutic exercises preceded by mechanical traction in treatment of patients with primary knee osteoarthritis attributed to the outcomes of pain, muscle strength, functional disability and functional performance.

Hypotheses

1. There will be no significant difference between therapeutic exercises and therapeutic exercises preceded by mechanical traction on reduction of knee pain severity in patients with primary knee osteoarthritis.
2. There will be no significant difference between therapeutic exercises and therapeutic exercises preceded by mechanical traction on reduction of functional disability in patients with primary knee osteoarthritis.
3. There will be no significant difference between therapeutic exercises and therapeutic exercises preceded by mechanical traction on increasing isometric quadriceps muscle strength in patients with primary knee osteoarthritis.
4. There will be no significant difference between therapeutic exercises and therapeutic exercises preceded by mechanical traction on increasing isometric hamstring muscle strength in patients with primary knee osteoarthritis.
5. There will be no significant difference between therapeutic exercises and therapeutic exercises preceded by mechanical traction on decreasing walking time in patients with primary knee osteoarthritis.
6. There will be no significant difference between therapeutic exercises and therapeutic exercises preceded by mechanical traction on decreasing ascending and descending stairs time in patients with primary knee osteoarthritis.

Knee osteoarthritis is the most common cause of musculoskeletal pain and disability, resulting in major disability and pain in affected individuals. It is a chronic degenerative disorder of multifactorial aetiology, including acute and/or chronic insults from normal wear and tear, age, obesity and joint injury. It nearly affects about one in each eight adults worldwide, its prevalence rates vary from 7.8 to 9.3% in Egyptian population.

Current clinical guidelines recommend non pharmacological conservative strategies including physical therapy given their ease of application and relatively low cost with minimal adverse effects (e.g.: strengthening exercises, aerobic exercises, stretching exercises, hydrotherapy, manual therapy, massage therapy, thermotherapy, electrotherapy, ultrasound therapy, external support braces and taping).

It was reported that therapeutic exercise is beneficial for patients with knee osteoarthritis in terms of outcomes of pain, function, performance and quality of life. In addition, it was reported that strengthening, flexibility and neuromotor skill exercises have a large efficacy over aerobic and mind body exercise.

Unloading strategies should be proposed as a first line of therapy for the patient with knee osteoarthritis before any attempts are made at tissue regeneration, repair or replacement.

Manual or mechanical knee joint distraction is a conservative technique that provides transient joint separation and unloading that aids in improving clinical symptoms of patients.

Addition of mechanical knee distraction to therapeutic exercises helps in gaining the positive effects of both exercise and unloading techniques. Although this approach has not been used extensively or applied pragmatically, several studies were found showing promising results in terms of reducing pain at both rest and movement, improving knee flexion and extension range of motion, reducing disability, increasing functional abilities and improving the quality of life of patients.

Forty male and female patients with the diagnosis of primary knee osteoarthritis will be recruited in this study. All patients will be assessed and treated in the outpatient clinic of the faculty of physical therapy, Cairo University. Patients will be randomly distributed into 2 equal experimental groups: the first experimental group will receive therapeutic exercises (stretching and strengthening exercise) while the second experimental group will receive mechanical traction of the knee followed by therapeutic exercises. All patients will be treated for 12 sessions, 3 times per week each other day for 4 weeks. Clinical assessments will include assessment of pain severity, functional disability, isometric muscle strength, and functional performance.

Inclusion Criteria:

• Patients will have grade II of primary knee osteoarthritis.
• Patients with bilateral primary knee osteoarthritis, the more painful knee will be selected as the affected knee in this study.
• Age of patients will range from 45 years to 65 years old.
• Duration of illness will range from 3- 12 months.

Exclusion Criteria:

• Malignancy
• presence of skin lesions or infections at the treatment sites

Patients will be blinded to study hypotheses and informed only about comparing different programs of treatment of knee osteoarthritis. After randomization, participants will only be provided with details of the program they will be undertaking.