Indirect reduction technique via Nice knot for transverse fracture of patella

Abstract

To assess the outcomes in indirect reduction technique via Nice knot for transverse patellar fractures. The clinical data of 25 patients with transverse patellar fractures meeting the inclusion criteria between January 2017 and December 2018 were retrospectively analyzed. The patients were divided into trial group ( n=13) and control group ( n=12) according to different intraoperative reduction methods. No significant difference was found in gender, age, affected side, cause of fracture, classification, or the time from injury to operation between the two groups ( P>0.05). In the trial group, No.2 suture was used to cross the quadriceps tendon and patellar tendon to construct the Nice knot, then the suture was tightened to make the distal and proximal fracture segments contact in an indirect reduction pattern. Depend on Nice knot's sliding compression and self-stabilizing function, the suture mesh created an anterior tension band as a temporary fixation. In the control group, Weber's clamp was used to hold the fracture segments directly and fixed temporarily. After reduction, terminal fixation was conducted using a titanium Kirschner wire with titanium cable in both groups. The operation time, intraoperative blood loss, follow-up time, fracture healing time, and complications were recorded and compared in the two groups. At last follow-up, the knee function was evaluated according to the Böstman scoring criteria for efficacy in patellar fractures. The operation time in the trial group was significantly shorter than that in the control group ( t=-2.165, P=0.041). There was no significant difference of intraoperative blood loss between the two groups ( t=0.514, P=0.612). The incisions of the two groups healed by first intention. All the patients were followed up 12-16 months, with an average of 14.4 months, no significant difference was found in the follow-up time between the two groups ( t=-0.309, P=0.760). One patient in the control group developed soft tissue irritation symptoms at 1 day after operation, and no special treatment was given, the symptoms disappeared at 2 months after operation. The fractures of the two groups healed at the 12-week follow-up. During the follow-up, there was no complication such as loosening and fracture of titanium cables and tendon tissue calcification. At last follow-up, the Böstman score presented no significant difference between the two groups ( t=-0.086, P=0.932). In the trial group, an 80-year-old female patient was evaluated as good (score, 27) due to atrophy of the quadriceps femoris, leg weakness, and affected stair climbing, and the rest 24 patients were all evaluated as excellent. The indirect reduction with Nice knot can shorten the operation time in the treatment of transverse patellar fractures, and obtain good effectiveness.