Largest Ever Hip Fracture Fixation Study

With more than 1,000 patients, a new study from 10 specialist UK trauma hospitals involving over 50 surgeons is the world’s largest randomized trial to date on hip fracture fixation. The work, “Effect on health-related quality of life of the X-Bolt dynamic plating system versus the sliding hip screw for the fixation of trochanteric fractures of the hip in adults: the WHiTE Four randomized clinical trial,” was published in the January 3, 2021 edition of The Bone and Joint Journal.

The Founder and CEO of Dublin, Ireland-based X-Bolt Orthopaedics is Dr. Brian Thornes, who previously invented the ankle syndesmosis Tightrope (licensed to Arthrex Inc).

According to Dr. Thornes, a former orthopedic surgeon, “Hip fractures usually occur in the very elderly, who frequently have other pre-existing medical conditions. Mortality following hip fracture is significant, around 10% in the first month and up to 35% at one year. A key aim of hip fracture care is to maximise patient function and mobility, and prevent hospital readmissions and reoperations.”

“The study was powered on the clinical outcome (EQ5D [EuroQol Five-dimension Health Status and Index] score) at 4 months post-operatively, to assess the possible superiority of the novel X-Bolt XHS (expanding bolt) versus traditional lag screw fixation. Over 1,000 patients were deemed necessary for the trial, given the high mortality, and variability on patient scores due to incurrent medical issues.”

A total of 1,128 patients aged 60 years and older with a trochanteric hip fracture either received fracture fixation with the X-Bolt Hip System or a sliding hip screw (randomized with 564 participants in each group).

According to Dr. Thornes, “Patients were randomised on admission and had their surgery within 24 hours. The surgery for both implant groups was identical, except for the placement of an X-Bolt expanding bolt or traditional lag screw into the femoral head.”

“Patients were followed up at 4 and 12 months post-operatively, usually via telephone questionnaire. The results show that, on average, those treated with an X-Bolt XHS had higher mean outcome scores at 4 months versus those that had lag screw fixation. Failure of fixation in the femoral head (‘cut-out’) was exceedingly low in both groups, notably at 0.8% in the X-Bolt XHS group.”

“The X-Bolt scored better than the lag screw in the primary outcome ‘intention-to-treat’ (as randomized) with a mean difference +0.03). The mean difference rises to +0.04 if analysed ‘as treated’ (implant versus implant) in favour of the X-Bolt XHS. Cut-out rates for X-Bolt were less than the lag screw in the trial, and much lower than historical averages for the lag screw.”

The study’s primary outcome, intention-to-treat, did not reach statistical significance. The study authors concluded that the randomized groups (which were unequal) were small and not clinically relevant.