Spatiotemporal structuration of sensorimotor information during walking in knee osteoarthritis patients.

OBJECTIVE

Patients with knee osteoarthritis (KOA) exhibit proprioceptive deficits and changes in neuromuscular control, which may consequently lead to functional motor impairment. However, how altered proprioceptive feedback interacts with changed neuromuscular control after injury remains unclear. This study aimed to elucidate the spatiotemporal interaction patterns between lower-limb muscle activity and proprioceptive feedback in patients with knee osteoarthritis during walking, to reflect changes in their neuromuscular control mechanisms.

METHODS

Fifteen KOA patients and fifteen healthy controls were recruited for gait testing. Muscle activity and proprioceptive inputs were obtained via musculoskeletal model simulations combined with electromyography (EMG) signal processing. The sensorimotor information flow between muscles around knee joint and proprioceptive feedback was analyzed in both the time- and frequency- domains.

RESULTS

Time-domain analysis showed that, compared with healthy controls, the affected side of KOA patients exhibited significantly increased sensorimotor information density both inter-limb and intra-limb (p < 0.05), and the information flow from muscle activity to proprioceptive feedback was significantly increased (p < 0.05). Frequency-domain analysis further revealed that, compared with healthy controls, KOA patients exhibited significantly altered inter-limb and intra-limb coordination patterns, characterized by increased spindle-model information density and decreased GTO-model inter-limb density during stance (p < 0.05).

CONCLUSION

Patients with KOA demonstrated specific alterations in sensorimotor information density and direction of information flow compared with healthy controls. These findings revealed compensatory control strategies adopted by the nervous system in response to joint dysfunction and suggested that these characteristic changes could inform the future development of individualized rehabilitation interventions.