Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
McKenna EpiLog Fellowship in Population Health, at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Neurosurgery. 2023 Mar 1;92(3):623-631. doi: 10.1227/neu.0000000000002256. Epub 2022 Nov 28.
Few neurosurgical studies examine the July Effect within elective spinal procedures, and none uses an exact-matched protocol to rigorously account for confounders.
To evaluate the July Effect in single-level spinal fusions, after coarsened exact matching of the patient cohort on key patient characteristics (including race and comorbid status) known to independently affect neurosurgical outcomes.
Two thousand three hundred thirty-eight adult patients who underwent single-level, posterior-only lumbar fusion at a single, multicenter university hospital system were retrospectively enrolled. Primary outcomes included readmissions, emergency department visits, reoperation, surgical complications, and mortality within 30 days of surgery. Logistic regression was used to analyze month as an ordinal variable. Subsequently, outcomes were compared between patients with surgery at the beginning vs end of the academic year (ie, July vs April-June), before and after coarsened exact matching on key characteristics. After exact matching, 99 exactly matched pairs of patients (total n = 198) were included for analysis.
Among all patients, operative month was not associated with adverse postoperative events within 30 days of the index operation. Furthermore, patients with surgeries in July had no significant difference in adverse outcomes. Similarly, between exact-matched cohorts, patients in July were observed to have noninferior adverse postoperative events.
There was no evidence suggestive of a July Effect after single-level, posterior approach spinal fusions in our cohort. These findings align with the previous literature to imply that teaching hospitals provide adequate patient care throughout the academic year, regardless of how long individual resident physician assistants have been in their particular role.
很少有神经外科研究在择期脊柱手术中考察 7 月效应，并且没有使用精确匹配的方案严格控制混杂因素。
在经过关键患者特征（包括种族和合并症状况）的粗略精确匹配后，评估单节段脊柱融合术的 7 月效应，这些特征已知会独立影响神经外科手术结果。
回顾性纳入了在一家单中心多院区大学医院系统接受单节段后路腰椎融合术的 2338 名成年患者。主要结局包括术后 30 天内的再入院、急诊就诊、再次手术、手术并发症和死亡率。使用逻辑回归分析月份作为有序变量。随后，在对关键特征进行粗糙精确匹配前后，比较了手术在学术年开始和结束时（即 7 月与 4 月至 6 月）的患者之间的结局。经过精确匹配，共纳入了 99 对完全匹配的患者（共 198 例）进行分析。
在所有患者中，手术月份与索引手术后 30 天内的不良术后事件无关。此外，7 月份手术的患者不良结局无显著差异。同样，在精确匹配的队列之间，7 月份手术的患者不良术后事件也没有差异。
在我们的队列中，单节段后路脊柱融合术没有证据表明存在 7 月效应。这些发现与之前的文献一致，表明教学医院在整个学术年都能为患者提供足够的医疗服务，而不论个别住院医师助理在其特定角色中任职时间长短如何。
