Multiple Rod Construct for Occipito-Cervical Fusion: Overcoming Challenges With Enabling Technologies

Introduction Occipito-cervical fusion is a well-established procedure for numerous cranio-vertebral junction (CVJ) anomalies. Owing to the complex biomechanics at play in this region, rigid internal fixation with pedicle screws and rods is needed to provide stability for fusion and good clinical outcomes. However, the rates of implant failure are still worrisome, especially in individuals with compromised anatomy and physiology. We describe a method for using multiple rod constructs for instrumentation across the CVJ, making the construct biomechanically stable, achieving high fusion rates, and preventing complications such as implant failure. Methodology This is a retrospective observational study with 10 patients who underwent occipito-cervical fusion with navigation-guided cervical pedicle screw fixation and multiple rod constructs, with a minimum follow-up of 12 months. Clinical parameters, including Visual Analog Scale (VAS), Neck Disability Index (NDI), Nurick grade, and modified Japanese Orthopaedics Association (mJOA) score, were evaluated pre-operatively and at follow-up. Similarly, radiological parameters such as occiput to axis (O-C2) lordosis, subaxial cervical spine (C2-C7) lordosis, and clivus-canal angle (CCA) were evaluated. Assessment of fusion was done by CT scan at 12 months post-operatively. Results All patients improved in terms of clinical and radiological outcomes post-operatively. Early mobilization on post-op day 1 with a soft cervical collar was possible in all the patients. No evidence of implant failure was seen in any of the cases. On follow-up CT scans, bony trabeculae formation was seen in all the patients. Conclusion Multiple rod construct for stabilizing the CVJ for occipito-cervical fusion is associated with early mobilization and clinical as well as radiological improvement due to the biomechanically stable construct provided by multiple anchorage in the cervical spine and occiput. This leads to high fusion rates, especially in patients with compromised anatomy and physiology.