Vertebral Column Resection through Posterior Approach in Rigid Adult Scoliosis / 대한척추외과학회지

OBJECTIVES: To report the surgical technique and effectiveness in treating rigid adult scoliosis with one stage vertebral column resection and pedicle screw fixation through a single posterior approach(PVCR). MATERIALS AND METHODS: Twenty-one patients with low flexibility(less than 20~30%) subjected to PVCR were evaluated after a mean follow-up of 18.5 months(12~29 months). There were 10 males and 11 females. The mean age at the time of the operation was 32.1 years(19~61 years). Etiological diagnoses were idiopathic in 7, congenital in 12, neuromuscular in 2. Preoperatively, all the patients showed moderate to severe derangement of pulmonary function with reduced vital capacity(30%~57%). RESULTS: An average of 1.3 vertebrae(1~3 vertebrae) were removed. The resection of body was in thoracic in 12 and lumbar in 15. Posterior fusion was carried out in 6.8(3~12) levels. Following the surgery, preoperative thoracic scoliosis of 86degree(55~130degree) and lumbar scoliosis of 64degree( 35~110degree) were corrected to 38degree(15~65degree) and 25degree(14~61degree), showing a correction of 56.2%(39~78%) and 61.1% (44~82%) respectively. Preoperative kyphosis of 59degree(16~104degree) was corrected to 24degree(2~58degree), showing a correction of 60.2%(41~74%). Preoperative coronal imbalance and shoulder height difference was corrected to 0.6 cm and 1.0 cm respectively. The average operation time and transfusion were 253 minutes and 2835 ml. The complications comprised two transient neurological deficits, one aggravated neurological deficits, one monoparesis, one infection, and one pneumothorax. CONCLUSIONS: One stage posterior vertebral column resection is a promising new technique for rigid scoliosis, significantly reducing the operative time and morbidity of combined anterior-posterior resection.

Technique of Pedicle Screw Fixation and Derotation for the Improvement of Rotational Deformity in Scoliosis Surgery:Derotation:Screw Rotation / 대한척추외과학회지

STUDY DESIGN: This is a prospective design. SUMMARY AND BACKGROUND DATA: Derotation makes powerful coronal and satisfactory sagittal correction, however, making rotational correction is still controversy. OBJECTIVES: To introduce a new technique to improve the vertebral rotation. METHODS: 1. Fix the pedicle screws of concave side of thoracic spine with nut driver or derotator before derotation maneuver. 2. During the derotation (counter-clockwise), rotate the nut driver/derotator to the opposite direction (clockwise). RESULTS: A King type II AIS girl with the magnitude of right thoracic and left lumbar curve was 54 degrees and 40degress respectively was reviewed. Thoracic apical rotation was checked 32 degrees. When derotation maneuver was done, the Cobbs angle of thoracic verteba was corrected to 14 degrees (74.1%), however the apical angle was aggravated to 34 degrees . When derotation-screw rotation(DSR) was done, thoracic angle was corrected to 3 degrees with 94.4% of curve correction. The apical rotation was improved to 25 degrees. Preoperative 19.6 degrees of RAsac was corrected to 10.4 degrees showing 46.9% of correction. Postooperatively she was balanced inspite of overcorrection. CONCLUSION: Derotation itself did not improve or slightly aggravate the rotation of apical vertebra. Apical rotation was dramatically improved by derotation combined by screw rotation technique. Maximal curve correction was obtained without trunk decompensation. This new technique may replace the advantages of anterior instrumentation in better rotational correction and saving fusion levels.

Decompensation in Selective Thoracic Fusion by Segmental Pedicle Screw Fixation in King type II Adolescent Idiopathic Scoliosis (AIS): Causative Factors and its Prevention / 대한척추외과학회지

STUDY DESIGN: A retrospective study. OBJECTIVES: To find the causative factors which induce decompensation after selective thoracic fusion with segmental pedicle screw fixation in King type II AIS. SUMMARY OF LITERATURE REVIEW: Pedicle screw fixation enabling enhanced correction is increasing in use in idiopathic scoliosis. However, there are few reports on the decompensation after selective thoracic fusion with pedicle screw fixation in King type II AIS. MATERIALS AND METHODS: Thirty-nine King type II AIS patients subjected to selective thoracic fusion with pedicle screw fixation were analyzed after a minimum follow up of 1 year. They were reviewed using standing roentgenograms. Deviation of center of T1 from center sacral line greater than 2 cm was considered decompensation. RESULTS: Among 39 patients, compensation was in 35 while decompensation in 4 postoperatively. There was no significant differences between the two groups in preoperative thoracic or lumbar curve characteristics such as curve magnitude, apical deviation or apical rotation. There was a significant difference in thoracic curve correction and postoperative T-curve magnitude divided by preoperative L-curve respectively(p= 0.001). CONCLUSION: Decompensation with selective thoracic fusion with segmental pedicle screw fixation in King type II AIS was not induced by preoperative L-curve characteristics nor derotation maneuver. The factor of decompensation was overcorrection, i.e. if thoracic curve correction was more than 75% or if the magnitude of postoperative T-curve was 30% less than that of preoperative L-curve, there was a high risk of decompensation.