Changes in medio-lateral postural control mechanisms during gait following total knee arthroplasty

Abstract Background Patients who have total knee arthroplasty (TKA) likely suffer from decreased postural stability due to postoperative changes in musculoskeletal structure and loss of proprioception. The purpose of this experimental biomechanical study was to determine if patients who have TKA improve their dynamic postural control during walking after TKA as compared to before TKA. The secondary purpose was to assess changes in postural control between post-TKA patients and healthy controls. Methods Twenty-three patients who had primary knee osteoarthritis (OA) scheduled to undergo unilateral or bilateral TKA were prospectively enrolled. Each patient was tested at 3-month, 6-month, and 12-month after TKA. Ten healthy controls matched for age, sex, and Body Mass Index (BMI) were selected from a database of previous healthy volunteers without knee OA. Ten Vicon cameras and four AMTI force platforms were used to collect the marker and center of pressure (COP) data while participants performed gait. Results Initial improvement in double stance ratio was found by 6-month post-TKA compared to pre-TKA. Patients showed improved postural control as evidenced by faster medio-lateral COP velocity and decreased double stance ratio at 12-month post-TKA compared to pre-TKA (p Conclusion Patients exhibited improvement in dynamic postural control after TKA with time, but had higher variability in COP parameters during gait compared to controls. It is possible that therapy aimed to improve proprioceptive balance after TKA may improve dynamic postural control.