The purpose of this study was to evaluate and
compare the effect of short segment pedicle screw instrumentation and
an intermediate screw (SSPI+IS) on the radiological outcome of type
A thoracolumbar fractures, as judged by the load-sharing classification,
percentage canal area reduction and remodelling. We retrospectively evaluated 39 patients who had undergone hyperlordotic
SSPI+IS for an AO-Magerl Type-A thoracolumbar fracture. Their mean
age was 35.1 (16 to 60) and the mean follow-up was 22.9 months (12
to 36). There were 26 men and 13 women in the study group. In total,
18 patients had a load-sharing classification score of seven and
21 a score of six. All radiographs and CT scans were evaluated for
sagittal index, anterior body height compression (%ABC), spinal
canal area and encroachment. There were no significant differences
between the low and high score groups with respect to age, duration
of follow-up, pre-operative sagittal index or pre-operative anterior
body height compression (p = 0.217, 0.104, 0.104, and 0.109 respectively).
The mean pre-operative sagittal index was 19.6° (12° to 28°) which
was corrected to -1.8° (-5° to 3°) post-operatively and 2.4° (0°
to 8°) at final follow-up (p = 0.835 for sagittal deformity). No
patient needed revision for loss of correction or failure of instrumentation. Hyperlordotic reduction and short segment pedicle screw instrumentation
and an intermediate screw is a safe and effective method of treating
burst fractures of the thoracolumbar spine. It gives excellent radiological
results with a very low rate of failure regardless of whether the
fractures have a high or low load-sharing classification score. Cite this article
Ventral screw osteosynthesis is a common surgical
method for treating fractures of the odontoid peg, but there is still
no consensus about the number and diameter of the screws to be used.
The purpose of this study was to develop a more accurate measurement
technique for the morphometry of the odontoid peg (dens axis) and
to provide a recommendation for ventral screw osteosynthesis. Images of the cervical spine of 44 Caucasian patients, taken
with a 64-line CT scanner, were evaluated using the measuring software
MIMICS. All measurements were performed by two independent observers.
Intraclass correlation coefficients were used to measure inter-rater
variability. The mean length of the odontoid peg was 39.76 mm ( The cross-section of the odontoid peg is not circular but slightly
elliptical, with a 10% greater diameter in the sagittal plane. In
the majority of cases (70.5%) the odontoid peg offers enough room
for two 3.5 mm cannulated cortical screws. Cite this article: