Supinated Foot Posture Is Associated With Reduced Knee and Foot Function in Patients With Knee Osteoarthritis

Area of Science:

• Orthopedics
• Biomechanics
• Rehabilitation Science

Background:

• Knee osteoarthritis (KOA) significantly impacts lower limb function.
• Foot posture is a potential, yet understudied, factor influencing KOA.
• Understanding foot posture's role may optimize treatment strategies for KOA patients.

Purpose of the Study:

• To compare lower limb function between supinated and neutral foot postures in patients with KOA.
• To evaluate the association between foot posture and functional metrics prior to total knee arthroplasty (TKA).

Main Methods:

• Sixty-two female KOA patients were categorized into neutral (n=33) or supinated (n=29) foot posture groups using the Foot Posture Index-6 (FPI-6).
• Key functional parameters including femorotibial angle (FTA), knee flexion and ankle dorsiflexion range of motion (ROM), knee extension strength, toe grip strength (TGS), Timed Up and Go (TUG) Test, and knee pain were assessed.
• Statistical comparisons were made between the two foot posture groups.

Main Results:

• The supinated foot posture group demonstrated significantly reduced knee flexion ROM, ankle dorsiflexion ROM, knee extension strength, and TGS compared to the neutral group.
• A larger femorotibial angle (FTA) was observed in the supinated foot posture group.
• No significant differences in TUG test performance or reported knee pain were found between the groups.

Conclusions:

• KOA patients with supinated feet exhibit diminished lower limb strength and ROM.
• Integrating foot alignment assessment into KOA rehabilitation programs is recommended.
• Further long-term research is necessary to establish definitive causal links between foot posture and KOA progression.