Radiographic assessment of the tibiofemoral relationship in anterior cruciate ligament deficient knees.

BACKGROUND

The intercondylar roof line is one of the indicators used during anterior cruciate ligament (ACL) reconstruction to see the relation to the position of the tibial tunnel. The tibial tunnel can be made posteriorly in the anteriorly subluxated tibia. During ACL reconstruction, the tibiofemoral relationship of the opposite or normal knee should be considered. The purpose of this study was to examine the radiographic tibiofemoral relationship of the sagittal plane in a standing position in ACL deficient knees.

METHODS

In this study, 64 patients were evaluated for inclusion. Lateral radiographs of the injured and uninjured knee were obtained preoperatively in a standing position. The knee was fully extended with the opposite foot on a step, asking the patients to bear weight fully on one leg. The tibiofemoral relationship was evaluated in the radiographs.

RESULTS

The mean value of anterior tibial subluxation was 1.2 mm in the injured side and -1.6 mm in the uninjured side. The tibia was located in a significantly anterior position in the injured knee ( < 0.0001). The mean distance of the space for the ACL was 9.7 mm in the injured side and 10.7 mm in the uninjured side ( < 0.01). Roof-plateau angle averaged 63.6° in the injured side and 67.4° in the uninjured side ( < 0.001).

CONCLUSION

The tibiofemoral relationship of the ACL deficient knee was different from that of normal knee in the standing position. The relationship of the normal knee should be considered during ACL reconstruction and the risk of secondary lesions in the ACL deficient knee in activities of daily life should be considered.