The Application of 3D-Printed Microporous Laminae in Kyphosis Correction Surgery for Ankylosing Spondylitis: Minimum Two-Year Follow-Up.

Abstract

Study design: A retrospective study.

Objective: This study designed an innovative 3D-printed microporous lamina and aimed to evaluate the feasibility and effectiveness in kyphosis correction surgery for patients with ankylosing spondylitis (AS).

Summary of background data: Spinal osteotomy is a widely employed treatment for severe kyphotic deformities in AS. However, mitigating complications associated with osteotomy remains a significant clinical challenge.

Methods: A total of 72 consecutive patients with ankylosing spondylitis who underwent kyphosis correction surgery were analyzed. Customized 3D-printed microporous laminae were designed based on preoperative imaging and three-dimensional modeling of each patient's spinal anatomy. Patients were divided into two groups: Group A (25 patients), treated with the 3D-printed microporous lamina technique, and Group B (47 patients), treated using the traditional technique. Radiological assessments included bone fusion rate, global kyphosis (GK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL), osteotomy angle (OA), pelvic index (PI), pelvic tilt (PT), sacral slope (SS), and sagittal vertical axis (SVA). Clinical outcomes assessed were surgery-related complications, reoperation rates, operative time, estimated blood loss, postoperative hospital stay, and Scoliosis Research Society Outcomes Instrument-22 (SRS-22). All patients were followed up for at least two years postoperatively.

Results: The bone fusion rate in the 3D-printed microporous lamina group was 96%. There were no statistically significant differences between the two groups in terms of surgery-related complications, reoperation rate, estimated blood loss, postoperative stay, GK, TLK, LL, OA, PI, PT, SS, SVA, or SRS-22. Although the mean operative time was longer in Group A than in Group B, this difference was not statistically significant.

Conclusion: The use of 3D-printed microporous laminae in kyphosis correction surgery for ankylosing spondylitis provides a promising method for achieving high bone fusion rates through effective laminar reconstruction.