Experimental Execution of the Simulated Pivot-Shift Test: A Systematic Review of Techniques

Purpose: To conduct a systematic review to identify and summarize the various techniques that have been used to simulate the pivot-shift test in vitro. Methods: Medline, Embase, and the Cochrane Library were screened for studies involving the simulated pivot-shift test in human cadaveric knees published between 1946 and May 2014. Study parameters including sample size, study location, simulated pivot-shift technique, loads applied, knee flexion angles at which simulated pivot shift was tested, and kinematic evaluation tools were extracted and analyzed. Results: Forty-eight studies reporting simulated pivot-shift testing on 627 cadaveric knees fulfilled the criteria. Reviewer inter-rater agreement for study selection showed a kappa score of 0.960 (full-text review). Twenty-seven studies described the use of internal rotation torque, with a mean of 5.3 Nm (range, 1 to 18 Nm). Forty-seven studies described the use of valgus torque, with a mean of 8.8 Nm (range, 1 to 25 Nm). Four studies described the use of iliotibial tract tension, ranging from 10 to 88 N. Regarding static simulated pivot-shift test techniques, 100% of the studies performed testing at 30 degrees of knee flexion, and the most tested range of motion in the continuous tests was 0 degrees to 90 degrees. Anterior tibial translation was the most analyzed parameter during the simulated pivot-shift test, being used in 45 studies. In 22% of the studies, a robotic system was used to simulate the pivot-shift test. Robotic systems were shown to have better control of the loading system and higher tracking system accuracy. Conclusions: This study provides a reference for investigators who desire to apply simulated pivot shift in their in vitro studies. It is recommended to simulate the pivot-shift test using a 10-Nm valgus torque and 5-Nm internal rotation torque. Knee flexion of 30 degrees is mandatory for testing.