Monitoring surgical performance: an application of industrial quality process control to anterior cruciate ligament reconstruction

Quality control is receiving increasing attention from surgeons as a key to meeting the needs of patients and the requirements of health care authorities. The objective of the study was to evaluate a continuous monitoring program for surgical performance in anterior cruciate ligament reconstruction. We measured the differential anterior knee laxity immediately after anterior cruciate ligament reconstruction by two experienced surgeons. Surgical technique including the choice of ancillary devices and implant material was at the surgeon’s discretion. The target was an immediate postoperative differential knee laxity at 20° of knee flexion of −1.5 mm. The cumulative summation test (CUSUM) was used to detect inadequate performance. Seventy-nine consecutive patients were included in the study. Median postoperative differential knee laxity at 20° flexion was −2 mm (interquartile range −4 to 0 mm; SD = 2.3). The CUSUM test at 20° knee flexion emitted an alarm at the 12th procedure, indicating that performance was inadequate with a tendency for laxity to be above the target of −1.5 mm. Two alarms were emitted after the 28th procedure, indicating that laxity tended to be below the target. Monitoring of immediate postoperative differential anterior knee laxity in anterior cruciate ligament reconstruction is feasible and can provide useful information on actual surgeon performance. Clinical relevance: continuous monitoring of the quality of anterior cruciate ligament reconstruction may help surgeons to detect deviations from optimal performance when new surgical techniques and innovative fixation devices are introduced.