Outcomes and complications of the INFIX technique for unstable pelvic ring injuries with high-velocity trauma: a systematic review and meta-analysis.

Abstract

The pelvic INFIX technique has been proposed as a useful alternative to symphyseal plating for management of unstable pelvic ring injuries. The minimally invasive nature of the procedure, shorter operative time and less perioperative blood loss have been purported as potential advantages. This systematic review and meta-analysis were conducted to determine the outcomes and complications of the INFIX technique for unstable pelvic ring injuries. A systematic review of literature was performed on the PubMed, EMBASE and Scopus databases. Prospective and retrospective studies in all languages, whether comparative or non-comparative, pertaining to the use of INFIX in pelvic fractures were included. Studies which did not evaluate INFIX, case reports, conference abstracts and those with less than 10 cases were excluded. Cadaveric studies, technique papers and studies that did not describe the prespecified outcome measures were also excluded. Meta-analysis consisted of two different arms: a comparative arm, to compare INFIX to symphyseal plating, and a non-comparative meta-analysis arm, to determine pooled rates of outcomes and complications. Risk of bias was determined by the Methodological Index for Non-Randomised Studies (MINORS) tool. A total of 22 studies were included in the systematic review, of which 7 were comparative and 15 were non-comparative. 746 patients were included for qualitative analysis and pooled analysis done for 589 patients. The average follow-up of these studies ranged from a minimum of 5.4months to a maximum of 54months. Comparative meta-analysis (n = 3 studies) of plating and INFIX showed significantly lesser blood loss (mean difference = 176.46mL; 95% CI -207.54 to -145.38) and shorter operative time (mean difference = 26.43min, 95% CI -31.79 to -21.07) with INFIX, but no significant difference in the overall complication rates (OR 1.59, 95% CI 0.83-3.05) and functional outcome scores (mean difference = -2.51, 95% CI -5.73 to 0.71). Pooled analysis showed overall good radiological (mean percentage of excellent to good reduction = 91.4%, 95% CI 0.860-0.969) and functional outcomes (mean Majeed score = 86.48, 95% CI 83.34-89.61) with INFIX. The most common complications were lateral femoral cutaneous nerve (LFCN) injury (overall rate 28%, 95% CI 15.1-41%) and heterotopic ossification (HO) (overall rate 9.4%, 95% CI 5.5-13.3%); rates of other complications were low. Significant heterogeneity was noted in the pooled analysis of blood loss, operative time, functional outcome, HO and LFCN injury. The overall strength of evidence was found to be weak. The INFIX technique can be considered as a viable alternative to symphyseal plating for unstable pelvic ring injuries. It has the advantages of shorter operative times and less blood loss, along with comparable functional outcomes, when compared to plating. Overall, good functional outcomes can be expected. However, well-designed, multi-center randomized controlled trials are needed to conclusively prove the benefit of this technique.