Characteristics of isometric knee extensor strength in patients with medial patellofemoral ligament reconstruction using artificial ligaments

<p>Objective: The purpose of this study was to clarify the difference in knee extensor muscle strength in patients with medial patellofemoral ligament reconstruction (MPFLR) using artificial ligaments and MPFLR with concomitant tibial tubercle osteotomy (MPFLR+TTO).</p><p>Methods: Fifteen patients in the MPFLR group (follow-up time: 22.8±15.6 months) and 11 patients in the MPFLR+TTO group (follow-up time: 22.8±9.6 months) participated in the present study. The isometric knee extensor strength at 90° and 30° of knee flexion were measured for all participants. The differences and ratios in knee extensor strength between the operated and non-operated knees were determined.</p><p>Results: In the MPFLR group, there were no significant differences in isometric knee extensor strength between operated and non-operated knees. In the MPFLR+TTO group, the operated knee extensor strength was significantly lower than the non-operated knee. The isometric knee extensor strength ratio of the operated to the non-operated knee was significantly lower at 30° of knee flexion in the MPFLR+TTO group than in the MPFLR group.</p><p>Conclusion: Isolated MPFLR using artificial ligaments provided good recovery of knee extensor muscle strength. On the other hand, it was suggested that MPFLR with concomitant TTO remained the differences in knee extensor strength between operated and non-operated knees and postoperative recovery of knee extensor muscle strength was smaller than isolated MPFLR.</p>