There are two cartilage structures, called menisci, in each knee joint. A torn meniscus can be caused by a traumatic injury or aging-related degeneration. Osteoarthritis (OA) is a type of arthritis that is caused by the breakdown and eventual loss of another type of cartilage that covers the end of bones within a joint. In people who have knee OA, a meniscal tear can easily lead to disability. This study will compare the effectiveness of two recommended treatments, surgery and physical therapy, for people with a torn meniscus and knee OA.

OA is the most common form of arthritis in the United States. Symptoms of knee OA include pain in and around the knee that typically worsens with weight-bearing activities, morning stiffness, and tenderness. A person with OA who experiences a torn meniscus--a cartilage structure within the knee that provides stability and proper weight distribution--is especially at risk for disability. Past studies have shown that arthroscopic partial meniscectomy (APM), a type of knee surgery, usually relieves symptoms and improves function in people suffering from a meniscal tear. However, the success of APM is more variable among people with already existing OA. Clinicians are also uncertain about the short- and long-term benefits, drawbacks, and indications for APM in people with OA and meniscal tears. The purpose of this study is to compare the effectiveness of two treatments, APM surgery and standard physical therapy, for people with OA and a torn meniscus.

This study will last 12 years. At the initial study visit, participants will be randomly assigned to one of two groups.

• Group 1 participants will undergo APM surgery at a time that is convenient for the participant and surgeon. After surgery, participants will be referred for rehabilitative physical therapy to regain strength and flexibility of the knee. For participants who choose to do physical therapy, the duration of treatment will depend on individual progress.
• Group 2 participants will receive standard physical therapy to increase strength and flexibility of the knee. This will include one to three weekly exercise sessions over an 8-week period.

The study consists of up to 5 visits to the center:

• Visit 1, the enrollment visit: sign the consent form, fill out a questionnaire, have a physical examination of the knee and find out your treatment group (surgery or physical therapy
• Visit 2, at 3 months after enrollment: Fill out a questionnaire and have a physical examination of the knee
• Visit 3, at 18 months: Fill out a questionnaire, have an MRI of the knee (if eligible) and xrays of both knees
• Visit 4, at 5 years: Fill out a questionnaire, have an MRI of the knee (if eligible) and xrays of both knees
• Visit 5, at 12 years: Fill out a questionnaire, have a physical examination of the knee, have an MRI of the knee (if eligible) and xrays of both knees

Telephone calls: During the first 3 months of the study, all participants will receive check-up phone calls every 2 weeks, followed by quarterly phone calls for the initial 2 years in the study

Questionnaires: Participants will also complete mailed questionnaires at 6 months, and 1, 2, 2.5, 3, 3.5, 4, 4.5, 5, and 12 years after enrollment. The questionnaires will include questions about knee pain, ability to walk, recreational activities, general health, and satisfaction with with treatment.

Inclusion Criteria:

• OA symptoms lasting at least 1 month and managed with medications, activity limitations, and/or physical therapy
• At least one symptom consistent with a torn meniscus. Symptoms may include clicking, catching, popping, giving way, pain with pivot or torque, episodic pain, and/or pain that is acute and localized to one joint line.
• Available knee X-ray (within 6 months) and MRI (within 3 years)
• Evidence of osteophyte formation or cartilage fissure, tear, or loss on a knee MRI OR plain radiographic evidence of osteophyte formation or joint space narrowing
• Evidence of a meniscal tear (tear extending to surface of meniscus) on a knee MRI
• Willingness to undergo random assignment and sign an informed consent

Exclusion Criteria:

• Chronically locked knee
• Kellgren-Lawrence Grade IV status, indicating advanced OA and usually the need for total knee replacement
• Contraindication to MRI
• Radiographic chondrocalcinosis (a condition in which there are deposits of calcium pyrophosphate dihydrate [CPPD] crystals in one or more joints that eventually result in damage to the affected joints) AND acute symptomatic pseudogout
• Inflammatory diseases (e.g., rheumatoid arthritis, psoriatic arthritis, systemic lupus erythematosus, gout, pseudogout)
• Injection with viscosupplementation in the affected knee in the 4 weeks before study entry
• Any medical contraindications to surgery or physical therapy
• Both knees are symptomatic for meniscal tears and a candidate for bilateral APMs
• Prior surgery on an affected knee
• Pregnancy or possible pregnancy
• Claim filed for worker's compensation
• Unable or unwilling to give informed consent
• Unable or unwilling to attend physical therapy sessions at designated locations or in the community