ObjectiveThe diagnostic accuracy of US and MRI for identifying peroneal tendon tears is unknown. The aim of this study is to determine the accuracy of these modalities for the diagnosis of peroneal tendon tears.Materials and methodsStudies on diagnostic accuracy of MRI or US for peroneus brevis (PB) and/or longus pathology were searched in Scopus, EMBASE, and PubMed. Systematic review was performed using the QUADAS-2 tool. Pooled diagnostic accuracy of MRI and US were calculated by using a bivariate random-effects model.ResultsTwelve studies were included for analysis. Eight studies reported on MRI, three reported on US, and one study included both. Studies were all at a high risk of bias, with only one study satisfying at least two of the four risk-of-bias criteria. Reported accuracy data was heterogeneous for both MRI and US. For PB tear, US showed higher pooled sensitivity than MRI (US: 93%; 95% CI: 75%, 98%; MRI: 73%; 95% CI: 56%, 87%); and similar pooled specificity to MRI (US: 85%; 95% CI: 55%, 96%; MRI: 88%; 95% CI: 70%, 95%) For peroneus longus, US had high pooled sensitivity (94%; 95% CI: 71%, 99%) and specificity (94%; 95% CI: 79%, 98%), whereas MRI was similarly specific (91%; 95% CI: 76%, 97%) but less sensitive (60%; 95% CI: 35%, 85%).ConclusionUS was observed to be sensitive and specific for peroneal tendon tears, while MRI was found to be specific but insensitive. The scarcity of literature addressing this question and the heterogeneity of the results precluded any confident conclusion of the superiority/inferiority of either modality.Key PointsQuestionPeroneal tendon tears are a common cause of lateral ankle pain, but the accuracy of MRI and US for identifying these tears is unknown.FindingPooled data shows US to be both sensitive and specific and MRI to be specific and insensitive for peroneal tendon tears; however, the literature is scarce, at risk of bias, and results are inconsistent.Clinical relevanceMRI and US are commonly utilized to assess lateral ankle pain. Though pooled-data suggests that US may be more sensitive, confident conclusion of the diagnostic accuracy of these modalities is limited by the level-of and quality-of the available evidence.Key PointsQuestionPeroneal tendon tears are a common cause of lateral ankle pain, but the accuracy of MRI and US for identifying these tears is unknown.FindingPooled data shows US to be both sensitive and specific and MRI to be specific and insensitive for peroneal tendon tears; however, the literature is scarce, at risk of bias, and results are inconsistent.Clinical relevanceMRI and US are commonly utilized to assess lateral ankle pain. Though pooled-data suggests that US may be more sensitive, confident conclusion of the diagnostic accuracy of these modalities is limited by the level-of and quality-of the available evidence.Key PointsQuestionPeroneal tendon tears are a common cause of lateral ankle pain, but the accuracy of MRI and US for identifying these tears is unknown.FindingPooled data shows US to be both sensitive and specific and MRI to be specific and insensitive for peroneal tendon tears; however, the literature is scarce, at risk of bias, and results are inconsistent.Clinical relevanceMRI and US are commonly utilized to assess lateral ankle pain. Though pooled-data suggests that US may be more sensitive, confident conclusion of the diagnostic accuracy of these modalities is limited by the level-of and quality-of the available evidence.