BackgroundParaffin bath therapy is noninvasive and is widely used in various hand diseases. Paraffin bath therapy is easy to use, has fewer side effects, and can be applied to various diseases with different etiologies. However, there are few large-scale studies of paraffin bath therapy, and there is insufficient evidence of its efficacy. PurposeThe purpose of the study was to investigate the effectiveness of paraffin bath therapy for pain relief and functional improvement in various hand diseases through a meta-analysis. Study designSystematic review and meta-analysis of randomized controlled trials. MethodsWe searched for studies using PubMed and Embase. Eligible studies were selected based on the following criteria: (1) patients with any diseases of the hand; (2) comparison between paraffin bath therapy and no paraffin bath therapy; and (3) sufficient data on changes in the visual analog scale (VAS) score, grip strength, pulp-to-pulp pinch strength, or Austrian Canadian (AUSCAN) Osteoarthritis Hand index before and after paraffin bath therapy. Forest plots were drawn to visualize the overall effect. Jadad scale score, I2 statistics, and subgroup analyses were used to assess the risk of bias. ResultsA total of five studies included 153 patients who were treated and 142 who were not treated with paraffin bath therapy. The VAS were measured in all 295 patients included in the study, while the AUSCAN index was measured in the 105 patients with osteoarthritis. Paraffin bath therapy significantly reduced the VAS scores (mean difference [MD], −1.27; 95% confidence interval [CI] −1.93 to −0.60). In osteoarthritis, paraffin bath therapy significantly improved grip and pinch strength (MD −2.53; 95% CI 0.71-4.34; MD 0.77; 95% CI 0.71-0.83) and reduced the VAS and AUSCAN scores (MD −2.61; 95% CI −3.07 to −2.14; MD −5.02; 95% CI −8.95 to −1.09). DiscussionParaffin bath therapy significantly reduced the VAS and AUSCAN scores, and improved grip and pinch strength in patients with various hand diseases. ConclusionsParaffin bath therapy is effective for alleviating pain and improving function in hand diseases, thereby improving quality of life. However, owing to the small number of patients included in the study and its heterogeneity, a further large-scale, well-structured study is needed.