Sex-based differences and relationship with the restricted knee flexion angle due to aging: a comparative study

Area of Science:

• Gerontology
• Biomechanics
• Orthopedics

Background:

• The relationship between inferior patellar mobility (IPM) and knee flexion angle remains unclear.
• Quantitative measurement methods for IPM are needed.
• Understanding IPM in older adults is crucial for mobility and fall prevention.

Purpose of the Study:

• To develop quantitative IPM measurement methods.
• To clarify the relationship between IPM and knee flexion angle in community-dwelling older females.
• To establish reference values for IPM in young and older women.

Main Methods:

• Cross-sectional study involving 128 healthy older women (65-79 years) and 205 young adults (19-21 years).
• Objective measurement of IPM using a patellofemoral arthrometer (PFA).
• Reliability assessment of IPM measurements.

Main Results:

• The PFA demonstrated excellent intratester and intertester reliability (ICCs 0.87-0.99).
• Normal IPM range (displacement/height) was 5.1-14.3% for young women and 1.2-8.8% for older women.
• IPM was significantly lower in older women and positively correlated with knee flexion angle in those with limited flexion.

Conclusions:

• The developed PFA is a reliable tool for measuring IPM.
• Aging is associated with decreased IPM in women.
• IPM is correlated with knee flexion angle, particularly in older women with reduced knee flexion capacity.