Navigation-Assisted Minimally Invasive Direct Pars Repair for Lumbar Spondylolysis.

UNLABELLED: Spondylolysis is a common cause of mechanical low back pain in adolescent athletes. While nonoperative management is frequently successful, a subset of patients fail conservative treatment and require surgical intervention. Direct repair of the pars defect offers a motion-preserving alternative to fusion in appropriately selected patients, but traditional open and fluoroscopy-guided minimally invasive techniques are limited by soft-tissue morbidity and variability in screw placement accuracy, and detailed technical descriptions of navigation-assisted approaches remain limited in the literature. We present a detailed, illustrated technique for navigation-assisted minimally invasive direct pars repair, in which a single midline incision accommodates bilateral fixation with minimal soft-tissue disruption. Intraoperative navigation improves trajectory control and reduces reliance on fluoroscopy. This technique offers a reproducible, motion-preserving option for direct pars repair that improves accuracy and reduces surgical morbidity relative to existing approaches, though outcomes remain dependent on careful patient selection and navigation reliability, radiation exposure, and technical familiarity with guidewire and screw placement.

KEY CONCEPTS: (1)Navigation-assisted minimally invasive spine surgery technique allows pars screw placement through indirect visualization.(2)Single midline incision allows bilateral fixation with minimal soft-tissue disruption.(3)Motion-preserving alternative to fusion in appropriately selected patients.(4)Pitfalls include navigation error, inadequate compression across the defect, and poor patient selection (disc degeneration, large defects, or spondylolisthesis).