J Korean Orthop Assoc.  2007 Jun;42(3):332-339. 10.4055/jkoa.2007.42.3.332.

Comparison of Proximal Fusion to T1 or T2 in Double Thoracic Adolescent Idiopathic Scoliosis

• Kim JH
• Suk SI
• Kim SS

• KMID: 2186557
• DOI: http://doi.org/10.4055/jkoa.2007.42.3.332

Abstract

PURPOSE: To assess the results of double thoracic fusion using pedicle screw instrumentation fused proximally to T1 or T2 in patients with double thoracic adolescent idiopathic scoliosis (AIS).
MATERIALS AND METHODS
Forty patients with double thoracic AIS were analyzed retrospectively after a minimum follow-up of 2 years. The patients were divided into two groups according to the proximal fusion level: the T1 group (n=26) was fused to T1 and the T2 group (n=14) was fused to T2.
RESULTS
There were no significant differences in the preoperative curve characteristics between the two groups. In the T1 group, the preoperative upper curve magnitude of 38+/-7o and apical vertebral translation (AVT) of 8+/-6 mm were corrected to 17+/-7o (54% correction) and 4+/-3 mm (3 mm correction) at the final follow-up, respectively. In the T2 group, the preoperative upper curve magnitude of 37+/-5o and the AVT of 7+/-4 mm were corrected to 22+/-6o (42% correction) and 6+/-3 mm (1 mm correction) at the final follow-up, respectively. There was no difference in the correction of lower thoracic curve, sagittal alignment and balance between the two groups. There was a significantly better correction in the upper thoracic curve and T1 tilting in the T1 group than the the T2 group.
CONCLUSION
In double thoracic AIS, fusions to T1 and T2 produce satisfactory results. However, fusion to T1 is recommended for a better correction of the upper curve and T1 tilting.

Keyword

Idiopathic scoliosis; Double thoracic curve; Pedicle screw; Proximal fusion level

MeSH Terms

Adolescent*
Follow-Up Studies
Humans
Retrospective Studies
Scoliosis*

Figure

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  Fig. 1 (A) A 13-year-old girl with a double thoracic curve. She had an upper thoracic curve of 45°, lower thoracic curve of 55° and lumbar curve of 30°. T1 tilting of 15° and a shoulder height difference of 10 mm with the right shoulder elevated. (B) She was treated with double thoracic fusion using pedicle screw instrumentation from T1 to L1. Seven years and 6 months after surgery, the upper thoracic curve was corrected to 10°, the lower thoracic curve was corrected to 14° and lumbar curve was corrected to 12°. The T1 tilting was improved to 3° and the shoulders were level.

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  Fig. 2 (A) A 15-year-8-month-old girl with a double thoracic curve. She had an upper thoracic curve of 38°, a lower thoracic curve of 52° and a lumbar curve of 34°. T1 tilting was 10° and the shoulder height difference was 21 mm with the right shoulder elevated. (B) She was treated with the double thoracic fusion using pedicle screw instrumentation from T2 to L1. Two years and 6 months after surgery, the upper thoracic curve was corrected to 25°, the lower thoracic curve to 15° and the lumbar curve to 5°. The T1 tilt was aggravated to 16° and the shoulders were level.

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