Both posterior and anterior surgery have potential for complete scoliosis correction. Significant difference in judging the procedures still persists.

130 patients with idiopathic thoracic scoliosis were operated on by means of the same anterior instrumentation principle in the period from 1987 through 1998. There were 21 males and 109 females in the age of 16(±4). Patients were randomly chosen in the group with rib hump apical osteotomy added to the anterior instrumentation (group 1) and the group with the anterior instrumentation without rib hump osteotomies (group 2). A prospective study was performed. Preoperative and postoperative gibbometry was performed. Results were as follows: frontal correction: 67% for group 1., and 74% for group 2. Rib hump changed from 23 ± 15 to 6 ± 6.2 (74%) for group 1, and 20 ± 1.5 mm (62%) for group 2. Rib valley changed from 21 ± 11 to 7 ± 4 (63%) (group 1) and 37 ± 2.8 to 16 ± 3.4 (56%) (group 2). There were 4 hematothoraxes in group 2. and no haematothoraxes in group 1. It seems that rib hump osteotomy has no inßuence upon frontal scoliosis correction, and little inßuence upon rib valley correction. Signiþcant inßuence was noted upon rib hump correction. It might be that better spinal release and consecutive smaller corrective forces resulted in absence of haematothoraxes in group 1.

Double scoliotic curves usually demand long posterior fusion and limitation of lumbar motion. The purpose of the study was to determine a possibility of one stage surgery, 3D correction, balanced spine and maximum of lumbar mobility. Method: 47 patients in the age of 14±1.6 yrs with double IAS curves were operated from 1995–99 with an average follow up of 50±9 months. Untill 1998 all the patients (31) were fused from Th4 to Th12, leaving the fused curve in balance with compensatory lumbar curve (group1). From 1998–00, 16 patients underwent a single stage anterior surgery of boh curves from Th4-L3 if lower curve averaged 50û (group 2). Two independent observers analyzed the results. Results: G1 (Th 67û±10;L41û±11) was corrected to Th19û±4; L17û±4. Balance changed from 11 mm pre op. to 2.4 mm post op. However, 6 patients (avr. 70û+60û), were corrected to 25û+38û. One year of bracing was necessary to partially correct the disballance, with satisfactory overall results. In 3 patients (Th> 80, L> 50) a balanced spine resulted, but with problematic correction rate. In G2, correction was made from Th68û±17;L63û±10û, to Th23û±12;L21û±8. Mean op. time was 260 min., blood loss 640 ml, post.op. stay 12 days. Conclusion: Fusion down to Th12 showed good results if Th< 80 and L< 50 degrees. In greater curves, an extended single stage fusion down to L3 offered better overall results, better correction, no balance problems and good lumbar mobility.

A combined posterior-anterior approach is usually proposed for the fixation of highly unstable spinal lesions. A monocortical anterior fixation seems to become more and more popular. In the period from 1993 to 1998, 43 patients with minimally anterior and middle column destruction of thoracolumbar spine were anteriorly instrumented. There were 23 tumors, 11 specific infections, 5 posttraumatic conditions with failed posterior instrumentation, 4 acute fractures. Anterior instrumentation (45Nm rod-screw rotation rigidity) were used in all cases. A four screws principle with two non connected rods were bicortically applied to correct the deformity and to fix the corpectomy gap. No postoperative bracing was necessary. There was one pseudarthrosis 2yrs post op. due to poor anterior fusion in a posttraumatic case. In one case instrumentation failure occurred due to widespreading of the prostatic tumor. The study revealed no complications due to bicortical screw fixation in thora-columbar region. It is suggested that combined anterior and posterior procedure is only exceptionally necessary.

Inßuence of scoliosis surgery on pulmonary changes and even upon thoracic deformity changes are still controversial. The purpose of the study was to determine thoracic volume (TV) changes in patients operated on by means of posterior and anterior surgery because of severe thoracic AIS. 50 patients, operated by þrst author randomly chosen from the period 1993–97 were selected. In 25 patients (21 girls, 4 boys) anterior instrumentation was used (group 1), and posterior instrumentation in other 25 patients (20 girls, 5 boys; group 2). TV calculation was performed basing on preoperative and postoperative plain x-rays, using a well known equation (second and third, independent author). The curves were 73û ± 12.4 pre op, and 19û ± 15 post op (group 1), and 75û ±13 pre op., 37û± 10 post op. (group2). Calculated TV for group 1 increased from 5234 ml to 6043 ml postoperatively (17% ± 16). In group 2, TV increased from 5155 to 5489 to 4,371 (6% ± 7). The correlation between the Cobb angle change and the thoracic volume change was poor (+0.2 for group 1, -0.4 for group 2). To determine the role of frontal, sagital and vertical thoracic diameters in TV increase, further correlation tests were performed. The best correlation was found between the frontal and vertical diameter increase in anterior instrumentation (r=0.62; 0.71), whereas the best correlation was found between TV and sagital parameters in posterior instrumentation (r=0.74). It is concluded that anterior instrumentation can increase TV more than posterior instrumentation.