Study design: Surgical technical note and literature review.
Objectives: To describe a technique that uses 4 rod constructs in cases of complex thoracolumbar spinal deformity correction or revision surgeries based on the hybrid use of two different types of purchase points by a staggered pedicle screw fixation. It utilizes two rods on either side of the spine using a lateral and medial entry point of pedicle screws in the vertebral body.
Methods: Pedicle screws using extra-pedicular technique are more converging screws and are inserted alternately in the vertebral body and connected by rods. The left-out alternate vertebral bodies are fixed by a relatively straighter pedicle entry screw and connected to each other by a separate rod. So, two trajectories are independently used for a four-rod construct. This reconstruction has been named RCC (reinforced criss-cross construct). The screws in the index case were placed by free hand method, but we have increasingly utilized navigation guidance for placement of screws in recent times.
Results: We present a surgical technical note in a patient with human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV-AIDS). He was diagnosed to have multi-drug-resistant (MDR) tuberculous spondylodiscitis, complicated with Immune reconstitution inflammatory syndrome (IRIS) and implant failure resulting in kyphosis and thoracic myelopathy. RCC with pharmacological management achieved healing and union, which was maintained at 4 years follow-up. Our method of four-rod construct provides a strong and lasting construct in the management of spinal deformities and three-column osteotomies. It provides good structural support to the spine till bony union is achieved.
Conclusion: Hybrid multi-rod construct like RCC provides a rigid mechanical support to the instrumentation and reduces the chances of rod failure especially in complex thoraco-lumbar spinal deformity correction surgeries.
Keywords: Complex deformity; Hybrid pedicle fixation; Multi-rod; Navigation; Spine.
© 2022. The Author(s), under exclusive licence to Scoliosis Research Society.