Static Bilateral Plantar Load Sharing One Month After Total Knee Arthroplasty for Varus Osteoarthritis: A Prospective Pedobarographic Equivalence Study

Background and Objectives: Total knee arthroplasty (TKA) reduces coronal malalignment, but whether this correction redistributes load at the foot early after surgery is unknown. We evaluated static plantar load distribution before and one month after TKA and tested whether the magnitude of axial correction predicted the magnitude of load change. Materials and Methods: Sixty-four consecutive patients undergoing unilateral TKA for advanced knee osteoarthritis were enrolled prospectively; 60 completed both assessments. Hip–knee–ankle (HKA) angle, Q angle, and passive extension deficit were recorded preoperatively and at a mean of 30.9 ± 3.3 days postoperatively, together with static pedobarography of both feet in a bilateral stance under an instruction to load both limbs symmetrically. The primary outcome was the relative bilateral load share of the operative foot. Change scores were analyzed with paired tests, two one-sided equivalence tests (TOSTs), correlation, multivariable regression, and a linear mixed model.