Traditional tension band wiring (TBW) is the gold standard treatment for simple transverse patella fractures. Damage to soft tissues and malposition of metal-work can lead to complications.

A new study published in Injury tested three novel techniques for fixation of simple transverse patella fractures, to ease application without additional resources to traditional TBW.

Here, the biomechanical integrity of the novel techniques was tested against the traditional TBW. Overall, four configurations were assessed – two with longitudinal Kirschner Wires (LKW) and two with cross Kirschner Wires (CKW), fixed with either standard figure-of-eight (AO) or side TBW (STBW). An initial proof of concept human cadaveric study was conducted to ensure whether real world application of the constructs was feasible.

• Seventeen out of 22 specimens reached 100 cycles with peak loading ranging from 75 to 80 N.
• CKW with STBW showed best performances, with an average fracture displacement of 0.43 mm.
• On the other hand, LKW with STBW performed worst with the average fracture displacement of 1.93 mm.
• The incremental displacement/cycle for both CKW configurations was 0.27 mm, compared to 0.41 and 0.60 mm for both LKW constructs—suggesting that the CKW configuration conferred greater fixation stiffness under cyclic loading.

Hence, the results indicated that reorienting the plane of the wires and position of the cerclage TBW may reduce iatrogenic soft tissue injury—reducing operating time and the risk of complications. Thus, the findings demonstrated biomechanical superiority for CKW with either AO or STBW compared to LKW.

Source: Injury. 2020 Mar 25. pii: S0020-1383(20)30231-X. doi: 10.1016/j.injury.2020.03.010.