Ershela Sims

BACKGROUND AND AIMS: This study examines racial differences in gait mechanics in persons with knee osteoarthritis and the influence of anthropometrics, educational level, radiographic disease severity (rOA), and self-report measures of pain and disability on racial differences in gait. METHODS: One hundred seventy five (64 black and 111 white) adults with radiographic knee OA were tested. 3-D kinematic and kinetic data were collected while subjects walked at two self-selected speeds (normal and fast). Anthropometric data, radiographic level of OA, and self-report measures of pain and disability were also collected. Gait patterns were compared across groups and within groups. RESULTS: Black and white subjects did not differ significantly in radiographic OA. However, blacks walked significantly more slowly when asked to walk fast. At the normal speed, blacks had a smaller knee range of motion and loading rate than whites. Blacks also took longer to reach their peak maximum ground reaction force than whites. Within black subjects variations in gait mechanics were primarily explained by BMI, rOA, selfreported psychological disability, and pain self-efficacy. In white subjects, variations in gait mechanics were primarily explained by weight, age, velocity, psychological disability, and self-efficacy. CONCLUSIONS: Blacks in this study had a pattern of gait mechanics generally associated with high levels of osteoarthritis, though they did not differ significantly in rOA from whites. The variability in gait patterns exhibited by blacks was most strongly related to variance in walking speed, anthropometrics, and perceived physical ability. Taken together, these results suggest that race is an important factor that must be considered in the treatment and study of osteoarthritis.

OBJECTIVE: To examine the degree to which 2 commonly used measures of pain and disability, the Arthritis Impact Measurement Scales (AIMS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), relate to objective gait measurements. DESIGN: A descriptive study of the influence of self-reported pain and perceived functional impairment on gait mechanics in osteoarthritic adults. SETTING: A university clinical research laboratory. PARTICIPANTS: Overweight/obese adults with radiographic knee osteoarthritis (OA) as well as pain and disability associated with the disease (N=179). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The AIMS and WOMAC were administered to determine self-report measures of pain and disability. Speed, stride length, support time, knee angle, and peak vertical force (PVF) were determined from 3-dimensional kinematic and kinetic data collected on subjects walking at self-selected normal and fast speeds. Anthropometric data and radiographic levels of OA were also collected. RESULTS: Pearson correlation analysis showed that the AIMS physical disability score was inversely correlated with speed, stride length, and knee range of motion at both speeds and PVF at the fast speed. The WOMAC function score was inversely correlated with speed and stride length at both speeds and with PVF at fast speed. The WOMAC pain score was inversely correlated with speed and PVF at the fast speed. Regression analysis revealed that the AIMS physical disability score and body mass index accounted for the greatest variation in speed at the normal speed. Overall, AIMS physical disability and WOMAC function explained a larger proportion of variance in gait mechanics than radiographic measures of OA disease severity. CONCLUSIONS: Taken together, the results suggest that the AIMS physical disability and WOMAC function scores are associated with some important measures of gait impairment.