Hemivertebrae resection for unbalanced multiple hemivertebrae: is it worth it?

To assess the correction effect of hemivertebra resection for unbalanced multiple hemivertebrae by measuring corresponding parameters in both coronal and sagittal planes on series posteroanterior and lateral radiographs and report the related complications.

Twelve children with unbalanced multiple hemivertebrae were operated on by hemivertebra resection through a combined anterior and posterior approach or a posterior-only procedure. Mean age at time of surgery was 9.8 years (range 2–14 years). They were retrospectively studied with a mean follow-up of 48.7 months (range 30–60 months).

The mean Cobb angle of the main curve was 65.3° (range 45°–92°) before surgery and 13.8° (range 4°–30°) at the last follow-up. The correction rate was 80.0 % (range 65.5–92.4 %). The compensatory cranial curve was corrected from 25.8° (range 5°–53°) to 11.7° (range 0°–34°) with a correction rate of 65.9 % (range 33.3–100 %), and the compensatory caudal curve was corrected from 32.4° (range 17°–57°) to 7.1° (range 0°–20°) with a correction rate of 81.4 % (range 53.1–100 %). The angle of segmental kyphosis was 41.3° (range 12°–76°) before surgery and 17.0° (range −12° to 45°) at the final follow-up. The coronal imbalance was −1.0 cm (range −3.5 to 3 cm) before surgery and 0.0 cm (range −1.0 to 1.5 cm) at the most recent follow-up. The sagittal imbalance was 0.9 cm (range −3.2 to 3 cm) before surgery and 0.6 cm (range −3.0 to 3.5 cm) at the most recent follow-up. Complications including pedicle fractures, and pseudarthrosis were found in two patients (20 %).

In the patients with unbalanced multiple hemivertebrae, hemivertebra resection allows for excellent correction in both the coronal and sagittal planes, and great care should be taken to reduce the rate of complications.