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Background and Aims Peripheral nerve blocks are an increasingly common method of providing post-operative analgesia for shoulder surgery. However, the standard technique, the interscalene block (ISB), inevitably causes hemidiaphragmatic paresis (HDP), secondary to phrenic nerve palsy. This can cause morbidity in patients with pre-existing respiratory compromise, prompting investigation into alternative ‘phrenic-sparing’ nerve blocks. The aim of this review was to give an overview of these blocks and to critically evaluate the current literature to determine if any are suitable alternatives to the ISB. Incidence of HDP and analgesic efficacy were considered.Methods We queried four electronic databases and one register. Our initial search of online databases and registers yielded a total of 515 original papers following removal of duplicates. The titles and abstracts of these remaining articles were subsequently screened and 467 were removed following application of the inclusion and exclusion criteria. A total of 28 articles were included in the review.Results The use of ultrasound-guidance, lower volumes of local anaesthetic (LA) and injection 4 mm outside the brachial plexus fascia reduced HDP incidence for ISB, however no single modification did so sufficiently. While the superior trunk block (STB) showed comparable analgesic effect to ISB, HDP prevalence was also high. The posterior suprascapular nerve block (SSNB) produced consistently low HDP incidences but also inferior analgesia, except when combined with an infraclavicular brachial plexus block. The aSSNB provided equivalent analgesia to ISB while reducing HDP incidence. Lower LA volumes consistently led to lower HDP incidence across all blocks.Conclusions This review demonstrated that the extra fascial ISB, and combined posterior SSNB with infraclavicular block showed the greatest promise in providing an effective alternative to gold-standard ISB for those patients with significant pulmonary co-morbidities. Further investigation into the minimum effective volumes is warranted to determine if any of these blocks can successfully balance HDP prevention with analgesic efficacy.