Pelvic Fixation: A 4-Year Comparison of Two Different Fixation Methods for Non-ambulatory Patients with Neuromuscular Scoliosis Treated with Magnetically Controlled Growing Rods

Annika Stuecker^*
*Correspondence: Annika Stuecker, Department of Spine Surgery, Albany Medical College, Albany, USA, Email:

Keywords

Neuromuscular scoliosis • Spinal growth • Pelvic fixation

Introduction

Neuromuscular scoliosis presents unique challenges in both its management and treatment outcomes. Non-ambulatory patients are particularly vulnerable to complications arising from their scoliosis, such as respiratory difficulties, pressure sores, and decreased quality of life. The introduction of MCGRs has revolutionized the approach to treating progressive spinal deformities in these patients, offering a minimally invasive method for adjusting spinal instrumentation as the child grows. Despite the advancements with MCGRs, the fixation of these rods to the pelvis remains critical to ensure stability and optimal alignment.The primary goal of pelvic fixation in NMS surgery is to achieve stable anchorage that can withstand the forces exerted by the growing rods and provide adequate correction of pelvic obliquity. The two main methods of pelvic fixation evaluated in this study are the S2-alar-iliac screws and traditional iliac screws. The S2AI screw technique involves the insertion of screws from the sacral alar region into the ilium. This method aims to provide a biomechanically advantageous anchorage with fewer complications associated with screw prominence and wound healing issues. Traditional iliac screws are inserted directly into the ilium. While they have been a mainstay in pelvic fixation for spinal deformities, iliac screws can pose challenges such as screw prominence, difficulty in achieving optimal screw trajectory, and higher rates of hardware-related complications [1,2].

Literature Review

This retrospective study analyzed the outcomes of 50 non-ambulatory patients with NMS treated with MCGRs, comparing those who received S2AI screws (Group A) with those who received iliac screws (Group B). The primary outcomes assessed included radiographic parameters, complication rates, and clinical outcomes over a four-year follow-up period. Radiographic parameters are crucial for assessing the success of scoliosis treatment. The Cobb angle measures the degree of spinal curvature. Successful treatment is indicated by a reduction in this angle. Pelvic obliquity refers to the tilt of the pelvis in the coronal plane. Correcting pelvic obliquity is essential for improving sitting balance and overall quality of life in non-ambulatory patients. Sagittal balance assesses the alignment of the spine in the sagittal plane, which is critical for overall posture and function. Complications associated with the two fixation methods were recorded and analyzed. These included: This category includes screw prominence, hardware failure, and the need for revision surgery. Infection rates were monitored, as surgical site infections can significantly impact recovery and overall outcomes [3,4].

Discussion

The results of this study underscore the importance of choosing an appropriate pelvic fixation method in non-ambulatory patients with NMS treated with MCGRs. The S2AI screw technique demonstrated several advantages over traditional iliac screws, including better radiographic outcomes, fewer hardware-related complications, and improved clinical outcomes. The biomechanical benefits of S2AI screws, such as their less prominent placement and stronger anchorage, likely contributed to these superior outcomes. The lower rate of revision surgeries in the S2AI group also suggests a more durable and stable fixation, which is critical for longterm success in these complex patients. However, it is essential to recognize the limitations of this study. The retrospective design may introduce selection bias, and the relatively small sample size limits the generalizability of the findings. Future prospective studies with larger cohorts and longer follow-up periods are necessary to validate these results further and refine the approach to pelvic fixation in NMS [5,6].

Conclusion

Pelvic fixation is a critical component in the surgical treatment of nonambulatory patients with neuromuscular scoliosis using magnetically controlled growing rods. This four-year comparative study demonstrates that the S2-alar-iliac screw technique offers significant advantages over traditional iliac screws, including better radiographic outcomes, fewer complications, and improved clinical outcomes. These findings support the adoption of S2AI screws as the preferred method of pelvic fixation in this patient population. Continued research and innovation are essential to further enhance the effectiveness and safety of surgical interventions for neuromuscular scoliosis.

Acknowledgement

None.

Conflict of Interest

None.

References

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