WOMAC Osteoarthritis Index

WOMAC Osteoarthritis Index or the Western Ontario and McMaster Universities Osteoarthritis Index is a widely used measure of symptoms and physical disability, originally developed for people with OA of the hip or knee.

The WOMAC Osteoarthritis Index score was developed to evaluate clinically important, patient-relevant changes in health status as a result of intervention.

Evidence of the reliability (test–retest), validity, and responsiveness of the WOMAC score has been provided in OA patients undergoing total knee or hip arthroplasty and in OA patients receiving nonsteroidal antiinflammatory drugs (NSAIDs).

The WOMAC Osteoarthritis Index evaluates three dimensions::

• Pain (5 questions and 20 score)
• Joint Stiffness (2 questions and 8 score)
• Physical function (17 Questions and 68 score).

Each question is scores based on the severity of the answer, ranging from (0-4):

1. None: Scores (0)
2. Mild: Scores (1)
3. Moderate: Scores (2)
4. Severe: Scores (3)
5. Extreme: Scores (4)

Higher scores on the WOMAC score indicate worse pain, stiffness, and functional limitations.

There is also an index score or global score, which is most commonly calculated by summating the scores for the three subscales.

WOMAC Osteoarthritis Index

SECTION A: PAIN

The following questions concern the amount of pain the patient currently experiencing due to arthritis in the hips and/or knees.

For each situation, the patient enters the amount of pain recently experienced.

Question: How much pain do you have?	None	Mild	Moderate	Severe	Extreme
1. Walking on a flat surface
2. Going up or down stairs
3. At night while in bed
4. Sitting or lying
5. Standing upright.

SECTION B: JOINT STIFFNESS

The following questions concern the amount of joint stiffness (not pain) the patient are currently experiencing in his hips and/or knees.

Stiffness is a sensation of restriction or slowness in the ease with which you move your joints.

	None	Mild	Moderate	Severe	Extreme
1. How severe is your stiffness after first wakening in the morning?
2. How severe is your stiffness after sitting, lying, or resting later in the day?

SECTION C: PHYSICAL FUNCTION

The following questions concern the patient’s physical function. By this it means the patient’s ability to move around and to look after himself.

For each of the following activities, the patient should indicate the degree of difficulty he is currently experiencing due to arthritis in the hips and/or knees.

Question: What degree of difficulty do you have with?	None	Mild	Moderate	Severe	Extreme
1. Descending stairs
2. Ascending stairs.
3. Rising from sitting.
4. Standing.
5. Bending to floor.
6. Walking on flat.
7. Getting in/out of car.
8. Going shopping.
9. Putting on socks/stockings.
10. Rising from bed.
11. Taking off socks/stockings.
12. Lying in bed.
13. Getting in/out of bath.
14. Sitting.
15. Getting on/off toilet.
16. Heavy domestic duties.
17. Light domestic duties.

References

1. Bellamy N, Buchanan WW, Goldsmith CH, Campbell J, Stitt LW. Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee. J Rheumatol. 1988 Dec;15(12):1833-40. PMID: 3068365.
2. Bellamy N. Outcome measurement in osteoarthritis clinical trials. J Rheumatol Suppl. 1995 Feb;43:49-51. PMID: 7752137.
3. Bellamy N, Buchanan WW, Goldsmith CH, Campbell J, Stitt LW. Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee. J Rheumatol. 1988 Dec;15(12):1833-40. PMID: 3068365.
4. McConnell S, Kolopack P, Davis AM. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC): a review of its utility and measurement properties. Arthritis Rheum. 2001 Oct;45(5):453-61. doi: 10.1002/1529-0131(200110)45:5<453::aid-art365>3.0.co;2-w. PMID: 11642645.
5. Dutton’s Orthopaedic Examination, Evaluation, And Intervention 3rd Edition.