比较分析髋膝关节置换日间手术和与之倾向性匹配的住院手术术后90 d随访结果，以此来评估髋膝关节置换日间手术模式的安全性和有效性。

2019年12月至2021年12月，共有198例髋膝关节置换术在上海长征医院日间手术中心完成。纳入标准包括：年龄≤70岁；血浆白蛋白≥35 g/L；血红蛋白≥110 g/L；美国麻醉协会(ASA)分级为Ⅰ、Ⅱ级；身体质量指数(BMI)≤30 kg/m²。排除标准包括：关节畸形严重；既往心脑血管疾病、糖尿病、心律失常和严重肝、肾功能不全等。其中185例患者作为日间手术组(日间组)根据年龄、ASA分级和BMI与同期185例髋膝关节置换住院手术患者(住院组)倾向性匹配成功。该匹配队列包括227例全髋关节置换术、143例全膝关节置换术。回顾性分析了两组患者术后90 d内再手术、再入院、严重和轻微并发症、急诊就诊次数、计划外的门诊就诊情况，运用Wilcoxon秩和检验和卡方检验进行比较分析。

日间手术(日间组)和住院手术(住院组)患者人口统计学资料相似，反映了成功匹配。日间组和住院组的再手术发生率均为1.1%(χ²＝0，P＝1.000)，再入院发生率分别为2.2%、2.7%(χ²＝0，P>0.05)。总并发症、严重并发症、轻微并发症的发生率(χ²＝0.178、0、0.069，均为P>0.05)差异均无统计学意义。髋关节置换术后脱位的发生率分别为0.8%、0.9%(χ²＝0，P>0.05)；膝关节置换术后关节纤维化需麻醉下处理的发生率分别为3.0%、3.9%(χ²＝0，P>0.05)；急诊就诊的发生率分别为1.6%、2.2%(χ²＝0，P>0.05)；以上数据两组差异无统计学意义。在计划外门诊就诊方面，日间组和住院组的发生率(13.0% vs 5.9%，χ²＝5.333，P＝0.021)、日间组前93例和日间组后92例中的发生率(18.3% vs 7.6%，χ²＝4.665，P＝0.031)以及住院组和日间组前93例中的发生率(5.9% vs 18.3%，χ²＝10.394，P＝0.001)的差异具有统计学意义；而住院组和日间组后92例中的发生率(5.9% vs 7.6%，χ²＝0.280，P>0.05)的差异无统计学意义。

研究结果表明，在选择合适患者的情况下，髋膝关节置换日间手术模式具有与传统手术模式相似的安全性和有效性。

To evaluate the safety and feasibility of outpatient total hip and knee arthroplasties by comparing the results of 90-day follow-up after the operation between propensity matched cohorts that undergo inpatient vs outpatient total hip and knee arthroplasties.

From December 2019 to December 2021, a total of 198 hip and knee arthroplasties were performed in Ambulatory Surgical Center of Shanghai Changzheng Hospital. The inclusion criteria: age ≤70 years old; plasma albumin ≥35 g/L; hemoglobin ≥110 g/L; American Society of Anesthesiologists (ASA) grade Ⅰ and Ⅱ; body mass index (BMI) ≤30 kg/m². Exclusion criteria: severe joint deformity; patients with history of cardiovascular and cerebrovascular diseases, diabetes mellitus, arrhythmia, and severe liver or renal insufficiency and so on. Among them, 185 patients as the outpatient group were successfully propensity matched to 185 inpatients undergoing total hip and knee arthroplasty as the inpatient group, based on gender, age, ASA grade, and BMI. The matched cohort included 227 total hip arthroplasties(THAs) and 143 total knee arthroplasties(TKAs). Reoperation and readmission incidences, major and minor complications, emergency department visits, and unplanned outpatient visits within 90 days after surgery were retrospectively analyzed in the two groups. Wilcoxon rank sum test and Chi-square test were used for statistical analysis.

The demographics of patients undergoing outpatient surgery (outpatient group) and inpatient surgery (inpatient group) were similar, which meant a successful match. The rates of reoperations in both groups were 1.1% (χ²=0, P>0.05), and readmissions rates were 2.2%、2.7% respectively in two groups(χ²=0, P>0.05). No statistically significant difference was found in total complications, major complications, or minor complications(χ²=0.178, 0, 0.069, all P>0.05). Incidence of dislocation after THA were 0.8% and 0.9% respectively(χ²=0, P>0.05); the rates of arthrofibrosis requiring manipulation under anesthesia after TKA were 3.0% and 3.9% respectively(χ²=0, P>0.05), rates of emergency department visits were 1.6% and 2.2% respectively(χ²=0, P>0.05); all these data showed no statistically significant difference between two groups. In terms of unplanned outpatient visits, the incidences in the outpatient and inpatient groups(13.0% vs 5.9%, χ²=5.333, P=0.021), in the first 93 and last 92 of the outpatient group(18.3% vs 7.6%, χ²=4.665, P=0.031), and in the first 93 of the outpatient group and the inpatient group (5.9% vs 18.3%, χ²=10.394, P =0.001) showed statistically significant differences; while there was no statistically significant difference in incidence between the inpatient group and the last 92 of the outpatient group(5.9% vs 7.6%, χ²=0.280, P>0.05.

The results indicate that the model of outpatient hip and knee arthroplasties has similar safety and efficacy to the traditional surgical model among appropriately selected patients.