J Korean Soc Spine Surg.  2008 Mar;15(1):1-8. 10.4184/jkss.2008.15.1.1.

Posterior Hemivertebra Excision in Congenital Scoliosis

• Ahn JK
• Kim JH
• Kim SS
• Cho BC
• Jung NY
• Suk SI

• KMID: 1482837
• DOI: http://doi.org/10.4184/jkss.2008.15.1.1

Abstract

STUDY DESIGN: Retrospective study
OBJECTIVES
To evaluate the surgical outcome of congenital scoliosis with a hemivertebra treated by posterior hemivertebra excision and pedicle screw instrumentation. SUMMARY OF LITERATURE REVIEW: Posterior hemivertebra excision can be accomplished through a single posterior approach, and excellent correction and outcome may be achieved.
MATERIALS AND METHODS
Forty patients with one fully segmented hemivertebra treated by posterior hemivertebra excision with pedicle screw instrumentation were retrospectively analyzed after a minimum follow-up of 2 years (range 2~7.7 years). The mean age at surgery was 15.9 years (range 2.6~37.9 years). Preoperative and postoperative standing radiographs were used to assess radiographic parameters.
RESULTS
The average number of vertebrae in the major curve was 4.2 (range 3~8), and the average flexibility was 29% (range 8~59%). The average length of fusion was 3.5 segments (range 1~6). The number of fused vertebrae had a positive correlation with age at the index surgery (r=0.345, p<0.05). Mean preoperative scoliosis of 48+/-12degrees was corrected to a mean of 17+/-10degrees (65% correction), and mean preoperative kyphosis of 46+/-18degrees was corrected to a mean of 12+/-12degrees at the most recent follow-up. The compensatory curve had a mean of 25+/-10degrees preoperatively and spontaneously corrected to a mean of 8+/-8degrees (70% correction) at the most recent follow-up. The mean operating time was 233+/-81 min, with an average blood loss of 2904 ml. There was neither crankshaft phenomenon nor iatrogenic spinal stenosis in 6 patients under the age of 5 years after an average follow-up of 6 years.
CONCLUSIONS
Posterior hemivertebra excision using pedicle screw instrumentation in congenital scoliosis due to a hemivertebra is a safe and effective procedure. Posterior hemivertebra excision at an early age may reduce the fusion length while avoiding the induction of iatrogenic spinal stenosis during follow-up.

Keyword

Congenital scoliosis; Hemivertebra; Posterior hemivertebra excision; Pedicle screw instrumentation

MeSH Terms

Follow-Up Studies
Humans
Kyphosis
Pliability
Retrospective Studies
Scoliosis
Spinal Stenosis
Spine

Figure

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  Fig. 1. A 17-year-old male with a congenital kyphoscoliosis due to hemivertebra at T12. (A, B) He had a thoracolumbar scoliosis of 50。and a kyphosis of 60。. He was treated by posterior hemivertebra excision and fusion from T9 to L2 with pedicle screw instrumentation. (C, D) The preoperative 3D CT showed a fully segmented hemivertbra at T12. (E, F) The radiographs taken 3 years after surgery. His deformities were corrected to 11。 and 3。, respectively.

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  Fig. 2. A 3.7-year-old boy with a congenital scoliosis due to hemivertebra at T12. (A, B) He had a thoracolumbar scoliosis of 39。. He was treated by posterior hemivertebra excision with monosegment fusion. (C, D) The preoperative 3D CT showed a fully segmented hemivertbra at T12. (E, F) The radiographs taken 8 years after surgery. His deformity was corrected to 13。. (G, H) CT scans taken 3 and 7 years after surgery showed a normal growth of the instrumented vertebrae compared with the adjacent vertebrae. There is no iatrogenic spinal stenosis.

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