The aims of this study were to determine: (1) what factors predict patient self-estimated hand function; (2) what factors predict actual hand function; and (3) the relationship among actual hand function, patient estimates of hand function, and self-assessed activities of daily living (ADL).
Fifty-two patients with rheumatoid arthritis completed wrist and hand mobility measures, grip strength, pain, stiffness, and estimated hand function tests, along with the Sollerman Grip Function Test (actual hand function), Health Assessment Questionnaire (HAQ), and subscales of the Arthritis Impact Measurement Scales (AIMS).
Grip strength and stiffness were the strongest predictors of self-estimated hand function. Flexion and extension deficits in digits II through V were the strongest predictors of actual hand function. Actual hand function and self-estimated hand function were significantly correlated with each other and with the HAQ and AIMS subscales.
Measures of deficit are the most useful in predicting actual hand function, whereas measures of strength and flexibility are most useful for estimated hand function.