Objective A new type of tibialfemoral forcebalancing telemetry device was developed for measuring force balance on the tibialfemoral contact surface in knee joint. MethodThe forcebalance telemetry device was designed imitating the configuration of tibial part of total knee prosthesis, in which force sensors and telemetry circuit were embedded. During total knee arthroplasty(TKA), this device was implanted as a tibial prosthesis to measure tibialfemoral force while the knee joint was being placed at different angles. The tension balance was adjusted by releasing soft tissue around knee joint. ResultsThe results indicat that this device has advantage of high accuracy for force measurement (r>0.98,RMS= 65 g), which is sufficient to meet clinical demand. ConclusionsThe measurement of force balance on the tibialfemoral contact surface with telemetry device can provide new insight into the estimation of optimal knee prosthesis position and selection of appropriate polyethylene insert.