Purpose <p>Conservatively managed diaphyseal humeral fractures have demonstrated higher non-union rates than previously reported and there are drawbacks to functional bracing. There is a growing trend towards operative management of these injuries, yet there are several complications associated with current operative methods. This systematic review aimed to evaluate the role of elastic stable intramedullary nailing (ESIN) as a solution to mitigate these risks.</p> Methods <p>A systematic review and meta-analysis was performed using PubMed, EMBASE, MEDLINE and Cochrane databases. Methodology followed the Preferred Reporting Items for Systematic Reviews. Papers were screened using the screenatron SR software. Any differences of opinion regarding study inclusion were resolved through consultation with senior authors DT and AT. Data and outcomes were synthesised by two independent reviewers, and papers were assessed for bias and quality.</p> Results <p>Nine studies encompassing 264 patients, at a mean age of 40&#xa0;years old were analysed with a mean follow-up of 17&#xa0;months. The majority of these studies were of level four evidence (with only one study being level three). Two elastic nails were retrogradely inserted in most cases. Two hundred fifty-eight (98%) of patients achieved union, the average time to union was 14&#xa0;weeks. Studies demonstrated satisfactory, if not ‘good to excellent’ results across all, albeit heterogenous, measured outcomes. A low rate of complications such as radial nerve palsy and infection were found.</p> Conclusion <p>Current evidence supports the potential for increased use of ESIN for humeral shaft fracture management in adults. However, this study would encourage the further investigation of its efficacy through the development of a formalised surgical technique and the promotion of more high-quality comparative studies.</p>