Yoga for Managing Knee Osteoarthritis in Older Women: a Feasibility Study

The study hypothesized that it is feasible and safe to use Hatha yoga in older women with knee osteoarthritis (OA), and practicing Hatha yoga regularly will help reduce pain and stiffness, enhance physical function, and improve quality of sleep and quality of life in older women with knee OA.

1. Potential participants were initially screened via telephone by a trained research assistant for eligibility which was based on the following inclusion criteria:

   1. community-dwelling women aged 65 years or over;
   2. had a symptomatic OA of knee diagnosis for at least 6 months;
   3. had no previous training in any form of yoga; and
   4. were not currently participating in a supervised exercise program.
2. Once initial screening eligibility was established, the individual was seen at home to confirm:

   1. the presence of knee OA symptoms using the Clinical Criteria for the Classification of Idiopathic OA of the Knee developed by the American College of Rheumatology.
   2. Cognitively intact using the Short Portable Mental Status Questionnaire (SPMSQ).
3. Exclusion criteria included:

   * symptoms of joint locking;
   * instability indicated by chronic use of a knee brace, cane, walker, or wheelchair;
   * a corticosteroid injection in the symptomatic joint within three months of study entry;
   * a hyaluronic acid injection in the symptomatic joint within six months of study entry;
   * a history of knee surgery within the last two years or a joint replacement at any point;
   * individuals who had self-reported significant medical comorbidities that might preclude exercise participation such as: a) uncontrolled high blood pressure or existing heart condition; and b) other comorbid condition with overlapping symptoms (i.e. fibromyalgia, rheumatoid arthritis);
   * individuals who had medication changes for arthritis symptoms were permitted to remain in the trial; however, these changes were monitored.
4. Primary outcome measures included:

   - OA symptoms (e.g., pain, stiffness and physical function) were assessed using the Western Ontario and McMaster Universities OA Index scale (LK scale 3.1) (WOMAC) and a single question that asked about the number of pain medications used per day.
   * WOMAC scale contains 24 items divided into 3 subscales: Pain (5 items), Stiffness (2 items), and Physical Function (17 items). The 5-point Likert Scale uses the following descriptors for all items: none, mild moderate, severe, and extreme. These correspond to an ordinal scale of 0-4. The scores are summed for items in each subscale, with possible ranges as follows: pain=0-20, stiffness=0-8, physical function=0-68. A total WOMAC score is created by summing the items for all three subscales. Higher values represent a worse OA symptom.
5. Secondary outcome measures included:

   * physical performance of the LE which was assessed using the Short Physical Performance Battery (SPPB) developed by the National Institute on Aging. The test consists of three components: repeated chair stands, balance, and timed 8" walk. Each subscale 0 (worst performance) to 12 (best performance).
   * BMI in kg/m\^2 was calculated using the participant's weight and height.
   * Quality of sleep was evaluated using the Pittsburgh Sleep Quality Index (PSQI). A score of ≥ 5 on the PSQI total scale, which is computed as a sum of the seven subscales (e.g., sleep quality, sleep latency, sleep duration, sleep disturbance, sleep efficiency, and use sleep medication) is associated with clinically significant sleep disruptions, including insomnia and major mood disorders.
   * The self-perceived quality of life was assessed using the Short Form Health Survey (SF-12) which measures a total of 8 health domains: 4 physical and 4 mental component summary scales. Physical Health (physical functioning, role-physical, bodily pain, and general health)and Mental Health (vitality, social functioning, role-emotional, and mental health) Composite Scores (PCS \& MCS) are computed using the scores of twelve questions and range from 0 to 100, where a zero score indicates the lowest level of health measured by the scales and 100 indicates the highest level of health. The Cantril Self-Anchoring Ladder that measures both "current" and "in 5 years" using steps from 0 to 10, where "0" represents the worst possible life and "10" represents the best possible life.
6. Feasibility measures: Feasibility was measured by eligibility, recruitment, and retention rates.

   * The average number of yoga class attendance and minutes of home practice were used to measure the retention and adherence rates.
   * Acceptability was evaluated by the participants' perceived difficulty of the yoga class and level of enjoyment.
   * Perceived level of difficulty and enjoyment were rated by participants after completing the yoga program on two different scales of 1 - 10 where 10 represents "extremely difficult" and "most enjoyable", respectively.
   * Safety was assessed by recording the frequency of injuries that occur during group and home-based exercise sessions.
7. Demographic information (e.g., age, race/ethnic background, education level, annual household income, marital status, living arrangement, and type of insurance), and comorbidities were collected from all participants.

Eligibility Criteria:
Inclusion Criteria:

* community-dwelling women aged 65 years or over
* had a symptomatic OA of knee diagnosis for at least 6 months
* had no previous training in any form of yoga; and
* were not currently participating in a supervised exercise program
* cognitively intact

Exclusion Criteria:

* symptoms of joint locking;
* instability indicated by chronic use of a knee brace, cane, walker, or wheelchair;
* a corticosteroid injection in the symptomatic joint within three months of study entry;
* a hyaluronic acid injection in the symptomatic joint within six months of study entry;
* a history of knee surgery within the last two years or a joint replacement at any point;
* individuals who had self-reported significant medical comorbidities that might preclude exercise participation such as: a) uncontrolled high blood pressure or existing heart condition; and b) other comorbid condition with overlapping symptoms (i.e. fibromyalgia, rheumatoid arthritis) were also be excluded.