Our Summary

This research paper is about the complications that can occur after surgery for adult spinal deformity, particularly when long fusion constructs are used. The researchers used a previously established model of the upper and lower (thoracolumbar) spine to simulate various types of fusions. They then performed simulations of increasing spinal flexion (bending) to predict how much the spine could bend, the maximum passive moment (the force needed to cause bending), and the compression and shear forces on the spine.

Their results showed that for long fusions, where the upper instrumented vertebrae (UIV) is at T11 or higher, there was an increase in segmental flexion and passive moment at the proximal junction - the point where the fusion ends and the natural spine begins. This increased with the length of the fusion. The maximum shear force was also higher for the proximal junction at the upper thorax, when the UIV was at T6 or above. However, the compression forces were reduced by up to 44%.

The authors conclude that the length of the spinal fusion has a significant impact on the biomechanics of the proximal segment. They suggest that musculoskeletal modeling could be a useful tool to support planning of spinal instrumentation surgeries in the future.

FAQs

  1. What complications can occur after surgery for adult spinal deformity, especially when long fusion constructs are used?
  2. How does the length of spinal fusion impact the biomechanics of the proximal segment?
  3. How might musculoskeletal modeling be used in the planning of spinal instrumentation surgeries in the future?

Doctor’s Tip

One helpful tip a doctor might tell a patient about spinal fusion is to follow a strict post-operative rehabilitation program to strengthen the muscles surrounding the fused area and improve flexibility. This can help prevent complications and aid in the healing process. Additionally, maintaining a healthy weight and avoiding activities that put excessive strain on the spine can also help improve the long-term success of the fusion surgery.

Suitable For

Patients who are typically recommended for spinal fusion surgery include those with severe spinal deformities such as scoliosis, kyphosis, or spondylolisthesis, as well as those with spinal instability due to trauma, tumors, or degenerative conditions. Patients who have not responded to conservative treatments such as physical therapy, medications, and injections may also be considered for spinal fusion. Additionally, patients who experience chronic pain, weakness, numbness, or difficulty walking due to spinal conditions may benefit from spinal fusion surgery.

Timeline

Before spinal fusion:

  1. Patient experiences chronic back pain, numbness, weakness, or other symptoms related to spinal deformity or injury.
  2. Patient undergoes diagnostic tests such as X-rays, MRI, or CT scans to determine the extent of the spinal problem.
  3. Patient consults with a spine specialist to discuss treatment options, including the possibility of spinal fusion surgery.
  4. Patient undergoes pre-operative evaluations and tests to ensure they are healthy enough for surgery.
  5. Surgery is scheduled, and the patient receives pre-operative instructions and guidance on what to expect during and after the procedure.

After spinal fusion:

  1. Patient undergoes spinal fusion surgery, which involves fusing together two or more vertebrae using bone grafts, metal plates, screws, or rods.
  2. Patient stays in the hospital for a few days to recover and receive post-operative care.
  3. Patient experiences pain and discomfort at the surgical site, which is managed with pain medication.
  4. Patient begins physical therapy and rehabilitation to regain strength, flexibility, and mobility in the spine.
  5. Patient follows up with their spine specialist for regular check-ups and monitoring of the fusion site.
  6. Over time, the fusion site heals and the patient experiences improved spinal stability and reduced pain.

What to Ask Your Doctor

Some questions a patient should ask their doctor about spinal fusion based on this research paper include:

  1. How will the length of the fusion affect the biomechanics of my spine, particularly at the proximal junction?
  2. What are the potential risks or complications associated with long fusion constructs, such as increased segmental flexion and shear forces at the proximal junction?
  3. How will the location of the upper instrumented vertebrae (UIV) impact the biomechanics of my spine post-surgery?
  4. Are there any specific considerations or precautions that need to be taken during the planning of my spinal fusion surgery, based on the findings of this study?
  5. Can musculoskeletal modeling be used to help optimize the surgical plan for my spinal fusion procedure?

Reference

Authors: Ignasiak D, Peteler T, Fekete TF, Haschtmann D, Ferguson SJ. Journal: Eur Spine J. 2018 Sep;27(9):2262-2271. doi: 10.1007/s00586-018-5700-3. Epub 2018 Jul 23. PMID: 30039253