Summary
Pivot shift test after ACL reconstruction
Abstract
Purpose
The objective of this multicenter study was to evaluate the factors influencing postoperative positive pivot shift test after anterior cruciate ligament (ACL) reconstruction.
Methods
Six hundred sixty-three patients who had undergone ACL reconstruction with or without ACL remnant preserving techniques at 10 institutions were enrolled in this multicenter study. They were 339 males and 324 females whose average age at the surgery was 28.6 (12-66) years. Age, sex, body mass index (BMI), preoperative Tegner score, duration between injury and surgery, preoperative pivot shift grade, anterior knee laxity measured by KneeLax 3 arthrometer, lateral and medical meniscal status and its treatment and other parameters were assessed by logistic regression analysis. Postoperatively the grade of pivot shift test and anterior laxity were also evaluated one year after reconstruction.
Results
The postoperative side-to-side difference of anterior laxity was 0.9 ± 2.3 mm and the positive postoperative pivot shift test was fund in 101 patients (15.2%) one year after ACL reconstruction. The factors that significantly influenced the postoperative positive pivot shift test were female sex (odds ratio [OR], 1.58; P=0.041), preoperative side-to-side differences of anterior knee laxity (OR, 1.09; P=0.021), and reconstruction procedure (OR, 0.35; P=0.000). Interestingly, the postoperative positive pivot shift test was observed more frequently in the patients with ACL remnant sacrificing reconstruction than those with remnant preserving technique.
Conclusions
Female sex and larger preoperative anterior laxity of the knee were significantly associated with the postoperative positive pivot shift test. The patients who had undergone ACL reconstruction with remnant preserving technique demonstrated lower postoperative positive pivot shift test compared to ACL reconstruction sacrificing ACL remnant. Careful postoperative management should be important for the patients who have those risk factors for residual rotational laxity. ACL reconstruction with remnant preserving technique is recommended to reduce the postoperative rotational laxity for the patients whose remnant is preserved.