Suture Tape-Augmented Posterior Cruciate Ligament Repair Should Be Tensioned and Fixed at Approximately 100° Knee Flexion to Prevent Loss of Full Flexion.

purposeTo evaluate the biomechanics of simulated posterior cruciate ligament injuries (SimPCL) with and without internal brace suture tape augmentation (IBSTA) in cadaver knees.

methodsA total of 20 cadaveric knees were used, all male, with an average age of 65 ± 18 years. Femoral tunnel isometry was evaluated at the 1/11 o'clock and 2/10 o'clock femoral positions. SimPCL were created in 6 knees. IBSTA was performed, and load data were collected through knee range of motion. An additional 6 specimens were evaluated at the 1/11 femoral tunnel position, and load cell recordings were obtained at 10 different knee flexion angles. Cyclic displacement in 8 cadaver knees was assessed using an Instron machine. Load and displacement data were recorded. Testing was performed under 3 conditions for each specimen: intact PCL, SimPCL, and SimPCL/IBSTA using the 1/11 femoral tunnel position.

resultsThere was no difference in isometry when comparing the 1/11 o'clock (7.1 ± 4.0 ft∗lb) femoral position and the 2/10 o'clock (7.6 ± 4.2 ft∗lb) position (

conclusionsIn this cadaver study, there was a 1.18-mm average difference in posterior tibial displacement when comparing intact and SimPCL/IBSTA. The internal brace construct should be tensioned and fixed at approximately 100° of knee flexion to prevent loss of full flexion. CLINICAL RELEVANCE: The presented biomechanical data for internal bracing of PCL injuries may lead to improved surgical techniques.