Inter- and intra-operator variability associated with extracapsular suture tensioning

Abstract

To determine inter- and intra- operator variability associated with extracapsular suture tensioning as performed during lateral fabello-tibial suture placement. Ex vivo study. Fifteen Greyhound cadaveric pelvic limbs were prepared by cutting the cranial cruciate ligament and placing an extracapsular fabello-tibial suture. On two occasions, three surgeons tensioned the extracapsular suture of each stifle. Stifles were returned to 135 degrees of flexion and the suture tension was measured using a commercially available suture tensioner with inbuilt tensiometer. Intra-operator and inter-operator agreement were assessed using the limits of agreement method. A linear mixed effects model was specified to assess the effect of operator, repeated estimates and stifle order on tension applied. The mean difference within the three operators ranged from 0 to 14.7N. With 95% limits of agreement, on most occasions for all three operators, the difference was between -31.7 and 41.0 N. The mean difference between the three operators ranged from 6.0 to 30.7 N. With 95% limits of agreement, on most occasions the difference between operators was between -25.6 and 62.5 N. Marked variation exists in the tension applied during fabello-tibial suture application, both within and between surgeons. This variation may lead to inconsistent clinical outcomes. Further studies are required to determine the clinical consequences of this marked variation in extracapsular suture tensioning.