Loosening of pedicle screws is a major complication of posterior
spinal stabilisation, especially in the osteoporotic spine. Our
aim was to evaluate the effect of cement augmentation compared with
extended dorsal instrumentation on the stability of posterior spinal
fixation. A total of 12 osteoporotic human cadaveric spines (T11-L3) were
randomised by bone mineral density into two groups and instrumented
with pedicle screws: group I (SHORT) separated T12 or L2 and group
II (EXTENDED) specimen consisting of T11/12 to L2/3. Screws were
augmented with cement unilaterally in each vertebra. Fatigue testing
was performed using a cranial-caudal sinusoidal, cyclic (1.0 Hz)
load with stepwise increasing peak force.Aims
Materials and Methods
The results of the use of Harrington rods in the treatment of spinal fractures were reviewed. It was found that with burst fractures where the anterior pillar was deficient there was a significant incidence of loss of reduction. Anterior bone supplementation is recommended in these fractures when major loss of height or angulation occurs. Several technical faults were detected which, in most cases, also led to a loss of reduction. Almost all patients with an anatomical reduction were free of pain. There was no correlation between the loss of reduction and the lapse of time before operation, the levels of
