Ken Ishii1, Yuta Shiono, Haruki Funao, Kern Singh, Morio Matsumoto. 1. *Department of Orthopaedic Surgery, Keio University School of Medicine †Keio Spine Research Group (KSRG) ‡Department of Orthopedic Surgery, Nerima General Hospital, Tokyo, Japan §Department of Orthopedic Surgery, Rush University Medical Center, Minimally Invasive Spine Institute, Chicago, IL.
Abstract
STUDY DESIGN: Surgical technique. OBJECTIVE: To evaluate the efficacy of a novel groove-entry technique for thoracic percutaneous pedicle screw (PPS) insertion. SUMMARY OF BACKGROUND DATA: Minimally invasive spine stabilization (MISt) using posterior thoracolumbar instrumentation has many advantages over open procedures. Because of the variability among PPS entry points, the sloped cortex of the transverse process, and the narrow thoracic pedicle, thoracic PPS placement is technically challenging. MATERIALS AND METHODS: A retrospective review of 24 patients who underwent minimally invasive spine stabilization procedures involving 165 thoracic PPS placements using the novel technique was performed. The thoracic PPS entry is a groove formed by 3 bony elements: the cranial portion of the base of the transverse process, the rib neck, and the posterolateral wall of the pedicle. This groove can be easily identified under fluoroscopy with a Jamshidi needle allowing thoracic PPS insertion in the craniocaudal direction. RESULTS: Of the 165 thoracic PPSs placed, "Good" or "Acceptable" PPS placement accuracy was achieved in 152 (92.1%) and 164 (99.4%) placements, respectively. No complications such as organ injury, and screw loosening or breakage were observed with thoracic PPS insertion. CONCLUSIONS: This novel technique is both safe and reliable, with low misplacement and complication rates. In hospitals in which computer image guidance or navigation is unavailable, this groove-entry technique may become the standard for thoracic PPS insertion.
STUDY DESIGN: Surgical technique. OBJECTIVE: To evaluate the efficacy of a novel groove-entry technique for thoracic percutaneous pedicle screw (PPS) insertion. SUMMARY OF BACKGROUND DATA: Minimally invasive spine stabilization (MISt) using posterior thoracolumbar instrumentation has many advantages over open procedures. Because of the variability among PPS entry points, the sloped cortex of the transverse process, and the narrow thoracic pedicle, thoracic PPS placement is technically challenging. MATERIALS AND METHODS: A retrospective review of 24 patients who underwent minimally invasive spine stabilization procedures involving 165 thoracic PPS placements using the novel technique was performed. The thoracic PPS entry is a groove formed by 3 bony elements: the cranial portion of the base of the transverse process, the rib neck, and the posterolateral wall of the pedicle. This groove can be easily identified under fluoroscopy with a Jamshidi needle allowing thoracic PPS insertion in the craniocaudal direction. RESULTS: Of the 165 thoracic PPSs placed, "Good" or "Acceptable" PPS placement accuracy was achieved in 152 (92.1%) and 164 (99.4%) placements, respectively. No complications such as organ injury, and screw loosening or breakage were observed with thoracic PPS insertion. CONCLUSIONS: This novel technique is both safe and reliable, with low misplacement and complication rates. In hospitals in which computer image guidance or navigation is unavailable, this groove-entry technique may become the standard for thoracic PPS insertion.