Horizontal Versus Vertical Orientation of the Loop for Tension Band Wiring of Transverse Patella Fractures

Abstract

Conventional operative treatments of patella fractures are frequently associated with implant failure or displacement. Recent biomechanical studies showed that the orientation of the wire loop and the site of the wire twist can affect the fixation strength. The purpose of this study was to compare the clinical outcome of the tension band technique with loops in different orientations and different knot positions. For this retrospective study, 72 patella fractures (71 patients) were fixed with figure-of-eight configurations in combination with 2 K-wires. Patients were divided into 3 groups according to the orientation of tension band construct. A total of 40 patella fractures were placed with figure-of-eight configurations in a vertical orientation either with 1 wire twist (group 1; 16 patella fractures) or with 2 wire twists at the adjacent corners (group 2; 24 patella fractures). Thirty-two patella fractures were placed with figure-of-eight configurations in a horizontal orientation with 2 wire twists at the adjacent corners (group 3). Range of motion, complication rates, and knee scoring scales (Hospital for Special Surgery and Lysholm) were assessed during serial follow-up. Satisfactory reductions were achieved in all groups, but functional results in the early stage were different. Group 3 had better Hospital for Special Surgery and Lysholm scores at 3 months postoperatively; however, at 6 months and 1 year postoperatively, all groups had similar scores. At the 1-year follow-up, all groups achieved acceptable flexion and range of motion. The overall complication rate was lower in the horizontal group (12.5%). Placing the figure-of-eight tension band construct in a horizontal orientation can provide functional benefits in the early stage after patella fractures.

Modified two-tension-band for patellar fractures

“…5 The merits of the biomechanism for excellent postoperative outcomes are also supported by clinical research. 6,7 The present technique is similar to that used previously; 7 with four strands crossing the fracture site and two twists at the adjacent corner, this type of tension band technique complies with the biomechanical principles described by John et al 5 At the same time, research has shown that an additional cerclage wire increases the compressive strain. 17 All of these factors suggest that MTTB may be more effective than the AO TBW technique.…”

“…Due to the biomechanical merits described previously, 5 Lee et al 6 found that the loop of the horizontally oriented tension band with two-wire twists at the adjacent corners was better regarding satisfactory bony union, improved early functional outcomes, and a lower complication rate. In another study that used the two-tensionband technique for patellar fracture revision surgery in six patients with fixation failure following TBW, it was concluded that the two-tension-band technique may avoid technical errors and provide more secure fixation.…”

Cannulated Screws and Braided Polyester Tension Band as an Alternative for Fixation of Transverse Patella Fracture: A Finite Element Analysis Study

“…However, it has to be accepted that the strength of braided polyester tension band also depends on knot tying technique issues. 11,29,44,46,54,55 Clinical application of braided polyester needs to consider the knot tying issue.…”

“…11,44,45 Recent clinical studies found that a horizontal figure-of-eight wire loop resulted in a lower postoperative complication rate. 46 Interestingly, all research involving cannulated screw constructed a tension band with horizontal figure-of-eight loop through the screw's cannulation. 9,20,30,37,38 This raises a conflicting issue of the mechanical stress which may concentrate at the sharp corners as the wires exit on both ends of the screws.…”

“…18,31,32,34,36 Another variation includes horizontal orientation of the figure-of-eight loop which was proven to provide better fixation stability, compared to traditional vertically oriented technique. 11,[44][45][46] On the basis of the available evidence, it seems fair to suggest that combining the cannulated screws with horizontal braided polyester loop should provide a strong tension band construct. To our knowledge, there was only one literature focusing on this configuration, which was a biomechanical study in 13 cadavers.…”