Sliding hip screw vs intramedullary nail for AO/OTA31A1-A3: a systematic review and meta-analysis

to conduct a systematic review with consequent meta-analysis evaluating the best treatment for Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) 31A1-A3 trochanteric fractures when comparing the sliding hip screw (SHS) to the intramedullary nail (IMN). The outcomes used for comparison are major complications (in total, as well as nonunion and infection specifically), mortality rates, functional outcomes and patient-reported outcome measures (PROM).

Search strings for the Cochrane Library, CINAHL, Medline and Embase databases were developed with the help of a scientific librarian. Two authors screened the studies from the search string independently using Covidence.org and data extraction was performed similarly. Quality assessment was performed using the Cochrane Risk of Bias tool for randomised trials (ROB2) for RCT studies, and Cochrane Risk of Bias in Non-Randomised Studies - of Interventions (ROBINS-I) for non-RCT studies. Meta-analyses were performed using Log Risk Ratio as the primary effect estimate.

Of the 2,051 studies screened by the two authors, six RCTs and six non-RCTs were included in this meta-analysis, with a total of 10,402 patients. The results indicated no significant differences in total major complications, nonunion, infection or mortality between SHS and IMN treatments for AO/OTA 31A1, 31A2 and 31A3 trochanteric fractures. Due to a lack of compatible data, we were unable to perform a meta-analysis on function scores and PROM. However, there are trends that favour IMN for 31A1 and 31A2 fractures.

No significant difference between SHS and IMN was found in the meta-analysis in any of the examined AO/OTA fracture subtypes in terms of primary and secondary outcomes. When assessing function scores and PROM, we found trends favouring IMN for 31A1 and 31A2 fractures that should be explored further.