Bone & Joint Research. 2017 Apr;6(4):204-7.
Objectives
The Sliding Hip Screw (SHS) is commonly used to treat trochanteric hip fractures. Fixation failure is a devastating complication requiring complex revision surgery. One mode of fixa-tion failure is lag screw cut-out which is greatest in unstable fracture patterns and when the tip-apex distance of the lag screw is > 25 mm. The X-Bolt Dynamic Hip Plating System (X-Bolt Orthopaedics, Dublin, Ireland) is a new device which aims to reduce this risk of cut-out. However, some surgeons have reported difficulty minimising the tip-apex distance with subsequent concerns that this may lead to an increased risk of cut-out.
Patients and Methods
We measured the tip-apex distance from the intra-operative radiographs of 93 unstable tro-chanteric hip fractures enrolled in a randomised controlled trial (Warwick Hip Trauma Evalua-tion, WHiTE One trial). Participants were treated with either the sliding hip screw or the X-Bolt dynamic hip plating system. We also recorded the incidence of cut-out in both groups, at a median follow-up time of 17 months.
Results
There was a significantly increased tip-apex distance with the use of the X-Bolt (mean difference 3.7mm (95% confidence interval 1.58 to 5.73); SHS mean 17.1 mm, X-Bolt mean 20.8; p = 0.001. However, this was not associated with an increased incidence of cut-out at a median follow-up time of 17 months, with three cut-outs (6%) in the SHS group and 0 (0%) in the X-Bolt group.
Conclusion
The X-Bolt is a safe implant with no increased risk for cut-out. Concerns about minimising the tip-apex distance may be justified but do not appear to be clinically important.
Cite this article: Bone Joint Res 2017;6:204–207.
