Goreisan May Reduce Postoperative Swelling and Pain After Total Hip Arthroplasty: A Retrospective Comparative Study

<b>Background</b>: To our knowledge, the effect of Goreisan on edema following total hip arthroplasty (THA) has not been investigated, and its clinical efficacy in this context remains unclear. <b>Methods</b>: To elucidate these issues, we conducted a retrospective comparative study of 149 patients who underwent primary THA at our institutions, with group allocation based on treatment period. Patients were divided into control (<i>n</i> = 77, mean ± standard deviation age: 66.8 ± 9.8 years; 56 females) and Goreisan (<i>n</i> = 72, age: 65.6 ± 9.7 years; 53 females) groups, based on whether Goreisan was administered postoperatively for 7 days (2.5 g, three times daily). The primary outcome was CT-based postoperative swelling, assessed by thigh circumference and cross-sectional area, whereas pain and blood loss were evaluated as secondary outcomes. Correlation and multiple regression analyses were also conducted. <b>Results</b>: The postoperative blood loss was lower in the Goreisan group (451.2 ± 256.8 mL vs. 553.6 ± 301.9 mL, <i>p</i> = 0.036). The differences in thigh circumference and area were larger in the control group (+13.5 ± 12.6 mm vs. +1.9 ± 12.7 mm, <i>p</i> < 0.001; +11.1 ± 9.5 cm² vs. +2.7 ± 9.3 cm², <i>p</i> < 0.001). The enlargement ratios of thigh circumference and area were higher in the control group (+3.0 ± 2.96% vs. +0.41 ± 2.86%, <i>p</i> < 0.001; +6.96 ± 6.95% vs. +1.63 ± 5.70%, <i>p</i> < 0.001). Motion pain on postoperative day 7 was lower in the Goreisan group (1.71 vs. 2.18, <i>p</i> = 0.037). The differences and enlargement ratios of both the thigh circumference and area were associated with motion pain on postoperative days 1 and 7. In both cases, the correlations were stronger for circumference-related parameters than those for area-related parameters. <b>Conclusions</b>: These findings suggest that Goreisan may be associated with reduced postoperative swelling and pain after THA, although the results are observational and hypothesis-generating.