Abstract
AIMS: The aim of this systematic review and meta-analysis was to establish which intramedullary nailing technique, antegrade or retrograde, was associated with superior operative and/or functional outcomes in the treatment of humeral shaft fractures. METHODS: This SR was registered on the international prospective register of systematic reviews (PROSPERO) (CRD42022373170). The databases used to conduct the search for literature were Pubmed/Medline, Embase, Web of Science. References of all included studies were screened to identify papers not found in the initial database search.The inclusion criteria were; humeral shaft fractures treated with intramedullary nailing, direct comparison of antegrade and retrograde techniques, participants aged 16 and over, and outcomes of interest being reported. Exclusion criteria included pathological humerus fractures, humeral shaft fracture operative management for delayed, mal or non-union and studies with follow up time of less than 3 months. RESULTS: This review included three studies resulting in the analysis of 216 patients in total. The only significant surgical outcome was that surgical time (minutes) was found to be significantly shorter for the antegrade nailing group. The narrative synthesis suggested that antegrade nailing is associated with shoulder symptoms to a greater degree than retrograde nailing is for elbow symptoms. Risk of bias analysis found that all three included studies were at moderate risk of bias. CONCLUSIONS: There is not enough evidence to suggest whether antegrade or retrograde nailing results in better surgical or functional outcomes in the treatment of humeral shaft fractures. Sufficiently powered multicentre studies will be required to identify evidence-based advantages and disadvantages of both antegrade and retrograde intramedullary humeral nailing. LEVEL OF EVIDENCE: 1 - systematic review and meta-analysis.