Central and peripheral neuromuscular mechanisms underlying functional recovery heterogeneity in tibial plateau fractures

Functional recovery after tibial plateau fracture surgery shows substantial heterogeneity, with 30–40% of patients developing persistent limitations that extend beyond peripheral muscle deficits and may involve coupled central neural adaptations. We compared 32 patients with higher (Knee Injury and Osteoarthritis Outcome Score-Activities of Daily Living (KOOS-ADL) ≥80) and 32 with lower (KOOS-ADL ≤70) functional outcomes at 12 months post-surgery using synchronized three-dimensional motion capture, functional near-infrared spectroscopy, and surface electromyography during normal, dual-task, and balance-challenged walking. Routine gait revealed sensorimotor cortex hypoactivation and reduced affected-side ankle co-contraction in the lower-function group; dual-task walking exposed a marked affected-side ankle power deficit; and balance-challenged walking unmasked the largest discriminator, a 32.7% versus 7.3% knee coronal plane range-of-motion asymmetry ( d = 2.54), accompanied by bilateral dorsolateral prefrontal cortex deactivation and reduced antagonist co-contraction. These coupled cortical and muscular control deficits define a bone-brain-muscle signature of lower functional recovery and support precision rehabilitation targeting patients most at risk.