Comparison of clinical results of anatomic posterolateral corner reconstruction for posterolateral rotatory instability of the knee with or without popliteal tendon reconstruction.

BACKGROUND: It is unknown whether popliteal tendon reconstruction is necessary in anatomic posterolateral corner reconstruction, although the tendon has function in the varus and rotatory stability of the knee joint.

HYPOTHESIS: Anatomic reconstructions of the posterolateral corner with the popliteal tendon reconstructed will present better clinical and radiographic results than cases with the popliteal tendon not reconstructed.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: The authors retrospectively analyzed 32 cases of anatomic posterolateral corner reconstruction with a minimum 2-year follow-up. There were 17 cases of anatomic reconstruction with popliteal tendon reconstruction and 15 cases without popliteal tendon reconstruction. The authors compared preoperative and postoperative range of motion, varus instability by varus stress test, lateral joint opening on varus stress radiographs, posterolateral rotatory instability by dial test, Tegner activity score, Lysholm score, and International Knee Documentation Committee (IKDC) subjective knee evaluation form and knee examination form between the 2 groups. They also compared posterior translation on posterior stress radiographs in cases with posterior cruciate ligament reconstruction.

RESULTS: There was no difference in range of motion, varus stress test, dial test, Tegner score, Lysholm score, or the score by IKDC subjective knee evaluation form. The side-to-side difference in lateral joint opening on the varus stress radiographs significantly improved after anatomic reconstruction in both groups (P < .001, P = .001), but there was no preoperative or postoperative differences between the groups. No difference was found in the grade distribution on the IKDC examination form. In the cases with posterior cruciate ligament reconstruction, there was also no difference in posterior translation between the groups on posterior stress radiographs at the last follow-up.

CONCLUSION: No effect of popliteal tendon reconstruction was found in anatomic posterolateral corner reconstruction on the stability and clinical results.