Impact of pedicle screw accuracy on clinical outcomes after 1- or 2-level minimally invasive transforaminal lumbar interbody fusion

When creating minimally invasive spine fusion constructs, accurate pedicle screw fixation is essential for biomechanical strength and avoiding complications arising from delicate surrounding structures. As research continues to analyze how to improve accuracy, long-term patient outcomes based on screw accuracy remain understudied. The objective of this study was to analyze long-term patient outcomes based on screw accuracy. This is a retrospective cohort study of patients who underwent 1- or 2-level minimally invasive transforaminal lumbar interbody fusion and were queried from a prospectively maintained multisurgeon registry. Pedicle screws were assessed for accuracy and graded as poor, acceptable, or good. Patient demographic characteristics and outcomes including complications, patient-reported outcome measures (PROMs), return to activities, and fusion rates were compared between the cohorts. A total of 665 pedicle screws in 153 patients were evaluated and included in the final analysis. Of these, 20 (13.1%) patients had poor screws, 63 (41.2%) had acceptable screws, and 70 (45.7%) had good screws. All groups showed similar and significant improvements in all PROMs, although the poor screw group experienced delayed improvement in physical function. A majority of patients in all groups returned to working and driving and discontinued narcotics at similar rates. However, the poor screw group displayed significantly slower return to activities. There were no significant differences in intraoperative or postoperative complications, although the poor screw group experienced significantly lower fusion rates. Patients with poorly accurate pedicle screws experienced delayed return to activities and decreased fusion rates with similar long-term PROMs. Surgeons should continue to focus on placing accurate pedicle screws, and research should continue to analyze ways to ensure accurate screw placement.