[Early postoperative functional differences between total knee arthroplasties supplied with mobile-bearing platform...

The goal of this study was to analyze differences of gait patterns among patients with total knee arthroplasty supplied with mobile-bearing platform in contrast to patients supplied with fixed-bearing knee systems.

For that reason 17 patients with mobile-bearing knee systems and two groups of 15 patients each with fixed-bearing knee systems have been examined clinically, radiologically, and by means of gait analysis up to 6 months postoperatively. Additionally 20 knee-healthy control subjects have been gait-analyzed for comparison.

There existed no different developments of gait characteristics between the groups of patients in the preoperative status. After the operation an increase of the ground reaction force of the operated leg was observed in all groups. The functional range of motion in the operated knee joint improved among patients postoperatively. Besides, in the group with the mobile-bearing knee a significantly stronger flection of the operated leg during the stance phase under load could be proven. Between the groups of patients the average values of the respective radiological alignments did not exhibit statistically significant differences. No severe complications have been observed.

For the group of patients with fixed-bearing knee course samples have been registered, which approximate the reference values of healthy control subjects more strongly. The entire course sample is characterized by an increased range of motion of the opposite side and the adjacent joints. The parameters measurable in the gait analysis point to a better biomechanical situation after implantation of the mobile-bearing system.