The Effects of Knee Reconstruction on Combined Anterior Cruciate Ligament and Anterolateral Capsular Deficiencies

We tested the effect of intraarticular reconstructions of the anterior cruciate ligament alone and in combination with extraarticular reconstructions in 10 cadaveric knees. These knees had anterior cruciate ligament deficiency alone or in combination with anterolateral capsuloligamentous deficiencies. In the knees with combined injury, intraarticular reconstruction returned anterior stability to levels not significantly different from levels found for the knees deficient in the anterior cruciate ligament alone and treated with this proce dure. After intraarticular reconstruction, rotational sta bility of the knee with combined injuries failed to return to the levels seen in the knee with isolated anterior cruciate ligament deficiencies that underwent the same treatment. When a tenodesis with either 0 N or 22 N of tension was added to the intraarticular reconstruction in the knee with combined injuries, we found that ex cessive internal rotation significantly decreased at all angles of flexion, except at full extension with 0 N of tension. In addition, the extraarticular reconstruction with 22 N of tension in the tenodesis overconstrained the knee in internal rotation between 30° and 90° of knee flexion. The tenodesis with 0 N of tension over constrained the knee at only 60° and 90° of flexion. These results suggest extraarticular reconstruction as an adjunct to the intraarticular operation for the knee with anterior cruciate ligament and anterolateral struc tural injuries. The results also suggest that the surgeon can affect anterior and rotational laxity by adjusting the tension in the tenodesis.