3D‐Printed Laminae for Kyphosis in Ankylosing Spondylitis During Pedicle Subtraction Osteotomy

TL;DR

This study introduces 3D-printed laminae to improve spinal correction and reduce deformity in ankylosing spondylitis patients undergoing surgery.

Contribution

The novel use of 3D-printed laminae enhances posterior column stability during kyphosis correction in ankylosing spondylitis.

Findings

Implanted patients showed better kyphosis correction and less deformity loss compared to non-implanted patients.

Patients with 3D-printed laminae reported improved health-related quality of life and reduced back pain.

Two cases of sagittal reconstruction failure were observed in the non-implanted group.

Abstract

Ankylosing spondylitis (AS) often presents with spinal kyphosis, and pedicle subtraction osteotomy (PSO) is a common surgical technique for correcting AS‐related kyphosis. However, after PSO, the posterior column lacks rigid bone support, potentially leading to intervertebral disc mobility and loss of correction. This study aims to introduce a novel 3D‐printed laminae for the treatment of AS‐related kyphosis.

This is a retrospective cohort study. A total of 48 patients receiving posterior correction surgeries between December 2021 and January 2022 were included and divided into two groups according to whether they accepted the 3D‐printed laminae. We propose a novel approach using 3D‐printed laminae to enhance posterior column stability and reduce deformity loss. Sixteen patients receiving 3D‐printed laminae and 32 patients who did not receive that device. We collected preoperative and postoperative radiographic parameters, perioperative data, and patient‐reported clinical scores. Statistical analysis involved independent sample t tests or randomization tests for continuous variables and chi‐square tests for categorical variables.

In the implanted group, kyphosis was corrected from 75.88° preoperatively to 27.06° postoperatively, and in the unimplanted group, from 70.98° to 28.42°. At the last follow‐up, the ΔGK (global kyphosis) was 1.76° in the implanted group and 2.50° in the unimplanted group. PJA was 9.77° in the implanted group and 15.45° in the unimplanted group, showing significant differences. Two patients in the unimplanted group experienced sagittal reconstruction failure. Health‐related quality of life (HRQoL) scores improved in the implanted group, with back pain scores of 2.63 and Oswestry Disability Index (ODI) scores of 13.50.

Our study introduces a novel 3D‐printed laminae technique for AS‐related kyphosis, aiding in maintaining sagittal balance. Patients reported improved subjective outcomes, including reduced pain and better HRQoL.

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