Concurrent Change in Quadriceps Strength and Physical Function Over Five Years in the Multicenter Osteoarthritis...

Area of Science:

• Orthopedics
• Rehabilitation Medicine
• Gerontology

Background:

• Quadriceps weakness is common in knee osteoarthritis (OA) and linked to functional limitations.
• Limited data exist on the functional benefits of modest strength gains in knee OA patients.
• Understanding this relationship is crucial for optimizing OA treatment strategies.

Purpose of the Study:

• To evaluate the concurrent changes in quadriceps strength and physical function over a 5-year period in individuals with knee OA.
• To determine if modest increases in knee extensor strength correlate with improvements in specific physical functions.

Main Methods:

• Analysis of data from the Multicenter Osteoarthritis (MOST) study, excluding participants who underwent knee replacement.
• Categorization of participants based on a ≥15% increase, decrease, or no significant change (within 15%) in knee extensor strength over 5 years.
• Assessment of physical function using the 5-times sit-to-stand test, 20-meter walk test, and WOMAC function scores, with stratified analyses by sex and baseline strength.

Main Results:

• Over 5 years, 22% of men and 30% of women achieved at least a 15% increase in knee extensor strength.
• Women with increased strength showed improved chair stand performance (OR 2.27) compared to those with stable strength, but no other functional gains.
• Increased strength was not significantly associated with improved physical function in men, nor with most functions in women.

Conclusions:

• Modest improvements in quadriceps strength are associated with better chair stand performance in women with knee OA, but not in men.
• Significant improvements in overall physical function did not accompany strength gains in most participants.
• Targeted interventions may be necessary to achieve broader functional improvements in knee OA management.