Hemi-Epiphysiodesis: The Convex Surface & Concave Surface



Hemi-epiphysiodesis is an operation that may be performed to try to stop an abnormal spinal curve (scoliosis) from progressing. Hemi-epiphysiodesis is most often used in cases of congenital scoliosis, meaning the condition was present at the time of birth, and the abnormal curvature is due to abnormally formed vertebrae, known as hemivertebrae. In hemivertebrae, only one side of vertebra form, and this causes the abnormal scoliosis curvature. 

Hemi-epiphysiodesis is usually performed on children over the age of five years who are still growing. When the growth of the bones on the convex side of the spinal curvature is stopped, it is hoped that growth will continue as normal on the concave side of the curve, and the curve will eventually improve. Growth is stopped in hemi-epiphysiodesis by removing the growth plates of the vertebrae on the convex side of the curve and then performing spinal fusion surgery to hold the vertebrae in place.  

Typically, following hemi-epiphysiodesis, children are required to wear a body cast for several months. This helps ensure the spine is stabilized in the correct alignment. The average degree of curvature correction achieved with hemi-epiphysiodesis is 10 degrees. 

Anytime spinal surgery, such as hemi-epiphysiodesis, is performed on a child who is still growing, the eventual outcome is difficult to predict.

Hemi-epiphysiodesis is typically performed using general anesthesia. Risks related to any surgical procedure include:

  • An allergic reaction to anesthesia
  • Breathing problems
  • Bleeding
  • Blood clots
  • A stroke or heart attack during the hemi-epiphydophesis
  • Infection

In addition, risks related to hemi-epiphysiodesis include:

  • Injury to the nerves that causes paralysis or muscle weakness
  • Lung problems may develop up to a week after hemi-epiphysiodesis

A child who has hemi-epiphysiodesis is at risk for future problems related to the procedure, including:

  • Pseudoarthritis: This painful condition occurs when the fusion does not heal and a false joint develops at the site of hemi-epiphysiodesis
  • Disc Degeneration: Because the fused portion of the spine does not move, other parts of the spine are subjected to increased stress, leading to early degeneration and back pain.
  • Pain due to movement of the spinal instrumentation (rods, screws, etc.) used during hemi-epiphysiodesis
  • New problems with the spine may be caused by hemi-epiphysiodesis, especially in children who have surgery while the spine is still growing.
convex / concave surface Treatments, Hemi-epiphysiodesis2-2