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Does operative start time influence the accuracy of cervical pedicle screw insertion using preoperative CT-based
Masashi Uehara1, Shota Ikegami1, Hiroki Oba1
1Department of Orthopaedic Surgery, Shinshu University School of Medicine, Nagano, Japan.
Purpose:
This study investigated whether procedures performed outside regular working hours affected the precision of cervical pedicle screw (CPS) insertion under computed tomography (CT)-based navigation guidance.
Summary Of Background:
Although navigation systems improve insertion accuracy, the impact of operative start time on CPS placement remains unclear.
Methods:
We retrospectively analyzed 138 patients (561 screws) who underwent CPS insertion using preoperative CT-based navigation between 2016 and 2022. CPS placement accuracy was assessed by postoperative CT and classified according to the extent of cortical perforation. Procedures initiated between 5:16 PM to 8:29 AM defined as after-hours. Multivariable generalized linear mixed models were constructed to identify factors associated with screw perforation.
Results:
Clinically significant perforation occurred in 10.0% (12/120) of screws placed during after-hours procedures and in 7.5% (33/441) of regular-hours placements. Multivariate analysis demonstrated that while screw placement in the middle cervical spine (C3-5) was independently associated with perforation (odds ratio: 3.31, p <0.01), operative start time was not (odds ratio: 1.07, p = 0.90).
Conclusions:
Operative start time was not independently associated with CPS placement accuracy in this cohort. Due to the wide confidence intervals, these exploratory findings do not establish the non-inferiority or equivalent safety of after-hours surgery. Further large-scale studies are warranted.
