Your doctor has likely asked you to rate your pain on a scale of 0 to 10. It's obviously subjective. Even so, your doctor can get a sense of an increase or decrease in your pain level over time. But how is physical function assessed in osteoarthritis patients? How is it determined that you have worsening physical function and that usual daily activities are becoming more difficult for you?
Doctors and researchers use several questionnaires that have been established as reliable tools for assessing the function of osteoarthritis patients. Not only do the assessments provide doctors with information about a patient's current level of function, the assessments can be compared for the purpose of identifying functional decline or improvement.
Popular assessments used to determine functional ability in osteoarthritis patients include:
The Lequesne Algofunctional Index
The Lequesne Index is a 10-question survey given to patients with osteoarthritis of the knee. It has 5 questions pertaining to pain or discomfort, 1 question dealing with maximum distance walked, and 4 questions about activities of daily living. The total questionnaire is scored on a 0 to 24 scale. Lower scores indicate there is less functional impairment.
The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)
The WOMAC OA Index is composed of 24 items in three subscales that evaluate pain (5 questions), physical function (17 questions), and stiffness (2 questions). Learn more about the WOMAC OA Index (PDF).
Katz Index of Independence in Activities of Daily Living
Bathing, dressing, toileting, transferring, continence, and feeding are assessed in the Katz Index of Independence in Activities of Daily Living. One point is given for each activity that can be performed independently and no points are given if help is needed. The score ranges from 0 to 6, with 6 being highest and indicative of independence. A zero score reflects a patient that is very dependent. Read more about the Katz ADL (PDF).
Instrumental Activities of Daily Living
The Instrumental Activities of Daily Living survey assesses functional capabilities of older patients. The survey is based on 7 criteria: use of a phone book to dial, answer, or find someone's phone number; traveling in a car or using public transportation; shopping for food or clothes; preparing meals; doing housework; using medications properly; and managing money. Each of the 7 criteria are graded as independent, assistance needed, or dependent. Two surveys are completed -- one by the patients and another by a nurse, family member, or caregiver.
The Arthritis Impact Measurement Scale
The Arthritis Impact Measurement Scale (AIMS) measures physical, social, and emotional well-being along 9 dimensions, including dexterity, mobility, pain, physical and social activity, and depression and anxiety.
Along with the surveys that are used to determine a patient's functional status, there are also some performance-based tests that are used to assess physical function. The performance tests may be more effective, in some cases, in predicting future disability than surveys. Some of the performance tests include:
- grip strength
- pinch strength
- manual dexterity
- timed walk
- standing from chair
- speed and mobility
- gait assessment
It's very important for a patient to get his or her initial symptoms assessed so an accurate diagnosis can be formulated. It's important to begin appropriate treatment as soon as possible, but it doesn't stop there. Doctors and patients must track how physical function is affected by osteoarthritis. What is the patient having problems with, and what solutions may be available? Functional assessment is just as important as diagnosis and treatment. It's part of living with arthritis.
Instrumental Activities of Daily Living. Family Practice Notebook. Scott Moses, MD. 1/13/2008. <www.fpnotebook.com/GER3.htm>.
Functional Assessment Measures. Osteoarthritis. Johns Hopkins. Joan M. Bathon, MD. Accessed 4/14/2008.
Measuring health status in arthritis: The Arthritis Impact Measurement Scale. Meenan RF, Gertman PM, Mason JH. Arthritis & Rheumatism 23, 146-152, 1980.