Percutaneous placement of pedicle screws is a
well-established technique, however, no studies have compared percutaneous
and open placement of screws in the thoracic spine. The aim of this
cadaveric study was to compare the accuracy and safety of these
techniques at the thoracic spinal level. A total of 288 screws were
inserted in 16 (eight cadavers, 144 screws in percutaneous and eight
cadavers, 144 screws in open). Pedicle perforations and fractures
were documented subsequent to wide laminectomy followed by skeletalisation
of the vertebrae. The perforations were classified as grade 0: no
perforation, grade 1: <
2 mm perforation, grade 2: 2 mm to 4
mm perforation and grade 3: >
4 mm perforation. In the percutaneous
group, the perforation rate was 11.1% with 15 (10.4%) grade 1 and
one (0.7%) grade 2 perforations. In the open group, the perforation
rate was 8.3% (12 screws) and all were grade 1. This difference
was not significant (p = 0.45). There were 19 (13.2%) pedicle fractures
in the percutaneous group and 21 (14.6%) in the open group (p =
0.73). In summary, the safety of percutaneous fluoroscopy-guided
pedicle screw placement in the thoracic spine between T4 and T12
is similar to that of the conventional open technique. Cite this article:
Low bone mass and osteopenia have been described in the axial and peripheral skeleton of patients with adolescent idiopathic scoliosis (AIS). Recently, many studies have shown that gene polymorphism is related to osteoporosis. However, no studies have linked the association between IL6 gene polymorphism and bone mass in AIS. This study examined the association between bone mass and IL6 gene polymorphism in 198 girls with AIS. The polymorphisms of IL6-597 G→A, IL6-572 G→C and IL6-174 G→A and the bone mineral density in the lumbar spine and femoral neck were analysed and compared with their levels in healthy controls. The mean bone mineral density at both sites in patients with AIS was decreased compared with controls (p = 0.0022 and p = 0.0013, respectively). Comparison of genotype frequencies between AIS and healthy controls revealed a statistically significant difference in IL6-572 G→C polymorphism (p = 0.0305). There was a significant association between the IL6-572 G→C polymorphism and bone mineral density in the lumbar spine, with the CC genotype significantly higher with the GC (p = 0.0124) or GG (p = 0.0066) genotypes. These results suggest that the IL6-572 G→C polymorphism is associated with bone mineral density in the lumbar spine in Korean girls with AIS.
Herniated intervertebral disc tissue has been shown to produce a number of proinflammatory mediators and cytokines, but there have been no similar studies using discs from patients with discogenic low back pain. We have compared the levels of production of