The Severity of Obesity and Knee Osteoarthritis: Effects on Strength and Gait

PURPOSE: The purposes of this investigation were to examine the relationships between severity of obesity (defined by BMI) and radiographic evidence of knee OA and their associations with abnormal joint loading, muscular weakness, knee pain, and function in older adults. METHODS: Baseline data from participants (n= 30) enrolled in the Fatty acids, Arthritis, and inflaMmation in the Elderly clinical trial were utilized for this study. Presence of knee OA was confirmed by a K-L score ≥ 1, and participants had to have a BMI ≥ 27.0 kg/m2. Internal knee moments, knee joint forces, and quadriceps and compressive forces were calculated using 3-D gait analysis with a 37-reflective marker set arranged in a Cleveland Clinic full-body configuration, a 6-Camera Motion Analysis System set to sample data at 60 Hz, and a torque-driven musculoskeletal model.27, 29 Quadriceps and hamstrings strength were assessed using an isokinetic dynamometer. Pair-wise Pearson correlations were computed between the outcome and explanatory variables. Generalized linear modeling was used to look for associations between the outcome and explanatory measures controlling for gender, race, and weight. RESULTS: Significant associations were found such that tall, heavy males were associated with greater internal knee extension moments and greater compressive forces and quadriceps forces. Height and weight were associated with increased quadriceps strength; however, only height was associated with increased hamstring strength. We also found a K-L score > 1 to be associated with an increased internal knee abduction moment. After adjusting for race, gender, and weight, increased pain and decreased function explained a significant amount of the variance with quadriceps force, while walking speed explained a significant amount of the variance with compressive and quadriceps force. CONCLUSION: It is well known that obesity is a major risk factor for knee OA. These data confirm associations between the internal knee extension moment and compressive forces which may accelerate disease progression. Other associations confirmed previous relationships identified in the literature.

Grantor dc:publisher

Wake Forest University

Year dc:date.issued

2009

Author dc:creator

• Pierce, Benjamin

• knee osteoarthritis

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10339/14737

OAI identifier oai:identifier

oai:wakespace.lib.wfu.edu:10339/14737