Can Dynamic Spinal Stabilization Be an Alternative to Fusion Surgery in Adult Spinal Deformity Cases?

When Orthrus and Peek rods are used, compressing the concave side and locking the rod to the screw in this manner is sufficient to provide additional improvement.

In kyphotic deformities, in the second stage, (A) the table is positioned under the scope, (B) normal sagittal balance is achieved, and the rods are placed.

In patients undergoing 2-stage surgery, temporary rods can be placed in the segments that were decompressed in the first stage. In this case, the risk of screw loosening in the relevant segments increases.

Patients are evaluated with computed tomography (CT) after an average of 16–20 weeks for the determination of osteointegration of screws. If osteointegration is completed, then rods are placed and screws are connected to each other. (A) Sagittal and (B) coronal CT image of patients showing screw loosening after traditional surgery with rigid stabilization. (C) Axial CT image of the patient showing successful osteointegration after the first stage of 2-stage surgery. (D) Lateral x-ray image of the patient after the second stage stabilization surgery by Dynesys system. (E) Intraoperative coronal fluoroscopy image and (F) CT image of the patient showing osteointegration after the first stage of 2-stage surgery. Red arrows indicate areas of connection between bone and screws.

Patient who previously underwent L3-L4 interbody fusion and L3-L4-L5 stabilization due to spondylolisthesis presented with worsening kyphosis and difficulty looking forward. (A) Preoperative standing lateral x-ray image, (B) first stage postoperative standing lateral x-ray image, (C) second stage postoperative standing lateral x-ray image, (D) sagittal magnetic resonance image (MRI) after initial L3-L4-L5 stabilization, (E) preoperative sagittal MRI showing proximal junctional kyphosis and Pfirrmann grade 4 intervertebral disc degeneration, and (F) second stage postoperative sagittal MRI. The Dynesis system was used for dynamic stabilization. Two-stage surgery was performed because the patient was osteoporotic (T score = −2.5 preop, –1.5 before the second stage). The patient showed significant improvement in both spinopelvic parameters and clinical findings after surgery.

Radiological images of a patient with neurological claudication and walking difficulties. Decompression and dynamic stabilization with the Orthrus system were performed. (A) Preoperative standing lateral x-ray image and (B) Postoperative standing lateral x-ray image showing sagittal imbalance and related pelvic parameters. (C and E) Preoperative sagittal magnetic resonance images and (D and F) preoperative axial magnetic resonance imaging (MRI), showing Schizas grade D and Lee grade 3 spinal stenosis. The patient showed significant increase in walking distance without difficulty.

Radiological images of a patient with lower back pain and walking difficulties. Decompression and dynamic stabilization with Dynesys system were performed. (A) Preoperative sagittal magnetic resonance image showing Pfirrmann grade 4 degenerative intervertebral disc changes. (B) Preoperative lateral x-ray image showing sagittal imbalance and pelvic parameters. (C) Postoperative lateral x-ray image showing improved sagittal balance.

Radiological images of 2 different patients with severe lower back pain and walking difficulties showing decompensated coronal imbalance. Both of the patients were decompressed and dynamically stabilized with Orthrus system. (A and C) Preoperative and (B and D) postoperative anteroposterior x-ray images showing significant improvement in coronal balance of the patients.