The investigators assessed overall physical activity and sleep quality in subjects with knee osteoarthritis(OA) at baseline, and at four and 12 weeks following initiation of physical therapy. Subjects received a course of manual physical therapy with interventions targeted to relevant impairments in the lower quarter. No progressive activity intervention or guidance on sleep hygiene was included. The purpose of this study was to assess a relationship between manual physical therapy and habitual physical activity and sleep behavior in individuals with knee OA.

Inclusion Criteria:

1. Knee pain and crepitus with active motion and morning stiffness < 30 minutes and age > 38 years old.
2. Knee pain and crepitus with active motion and morning stiffness < 30 minutes and bony enlargement.
3. Knee pain and no crepitus and bony enlargement.

Participants will have to meet all of the following additional inclusion criteria:

1. Age > 38 years old.
2. Tricare beneficiary
3. Ability to read and speak English well enough to provide informed consent and follow study instructions
4. Knee OA is the participant's most physically limiting condition as determined by patient's self report.
5. Able to ambulate 20 meters (65.6 feet) feet without an assistive device.
6. Radiographic findings of knee OA

Exclusion Criteria:

• 1.) Presence of any medical "Red Flags" affecting the knee:

  1. Tumor, neoplasm etc. affecting the knee

  2. Current or past history of rheumatoid arthritis or similar rheumatic condition

  3. Current or past history of gout or pseudogout affecting the knee

  4. Active Infection in the knee within the past 12 months

     2.) Inability to participate in the therapy plan prescribed by the treating therapist 3.) Any prior Physical Therapy for the knee in the past 12 months 4.) Injection to the knee joint within the previous 30 days 5.) Surgical procedure on either lower extremity within the past 6 months 6.) Any prior lower extremity joint replacement surgery 7.) A physical impairment unrelated to the knee that prevents the subject from safely participating in any aspect of the study 8.) History of cardiac, respiratory, or musculoskeletal disorders (e.g. amputation) that restrict lower extremity function. 9.) Any physical, psychological, or emotional condition that is more symptom producing, or activity limiting than their knee OA.

     10.) Any condition that disrupts sleep more than knee OA, such as a sleep disorder or Obstructive Sleep Apnea 11.) Inability to speak/read English adequately to understand and provide informed consent 12.) Pregnant or intending to become pregnant in the next year 13.) Military service members in a WTU (Warriors in Transition Unit) or service equivalent or pending a medical evaluation board/discharge process. For non-military personnel, anyone that is pending or undergoing any litigation. 14.) WOMAC Score < 30 15.) Unable to provide informed consent to participate in the study

Military Retirees and dependents receiving care for primary diagnosis of knee osteoarthritis.