A Modified Technique of Minimally Invasive Cortical Bone Trajectory Screws With U‐Rod for Treatment of Lumbar Spondylolysis

OBJECTIVE: Spondylolysis is a common cause of low back pain, especially in the young athletic population. It involves a defect, either unilateral or bilateral, of the pars interarticularis. Numerous techniques have been developed for the surgical treatment of spondylolysis, each with its own strengths and weaknesses. This article aims to describe a modified minimally invasive technique using cortical bone trajectory screws with a U-rod to stabilize the lumbar spondylolysis. METHODS: Adult patients who presented between July 2020 and August 2024 with low back pain due to spondylolysis were included in this study. Imaging studies of the lumbar spine were performed to confirm the spondylolysis. All patients were confirmed to be treated conservatively for at least 12 months prior to surgical intervention. A 2.5 cm midline incision was made at the level of the spondylolysis. Under fluoroscopic guidance, two screws were inserted into the level of the spondylolysis in the cortical bone trajectory, and the screws were connected with a U-shaped bent rod. RESULTS: Four adult patients (one male, three females) were included. The mean age was 38.5 ± 16.1 years. Average intraoperative blood loss was 6 ± 3 mL. Mean postoperative hospital stay was 3 ± 0.5 days. Both postoperative visual analog scale (VAS) and Oswestry disability index (ODI) scores showed significant improvement. Lumbar spine CT scans performed 1-year post-operation confirmed fusion of the pars defect in seven of the eight defects. CONCLUSION: We described a modified minimally invasive technique for the treatment of spondylolysis. This approach offers the advantage of being minimally invasive, leading to less blood loss, short hospital stays, and fast recovery. It also requires less technical expertise than traditional pars screw placement and utilizes readily available instrumentations. Patients reported improved pain scores, and imaging confirmed successful fusion of the pars defect.