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 presence of facet tropism has been correlated with an elevated susceptibility to lumbar disc pathology. Our objective was to evaluate the impact of facet tropism on chronic lumbosacral discogenic pain through the analysis of clinical data and finite element modelling (FEM). Retrospective analysis was conducted on clinical data, with a specific focus on the spinal units displaying facet tropism, utilizing FEM analysis for motion simulation. We studied 318 intervertebral levels in 156 patients who had undergone provocation discography. Significant predictors of clinical findings were identified by univariate and multivariate analyses. Loading conditions were applied in FEM simulations to mimic biomechanical effects on intervertebral discs, focusing on maximal displacement and intradiscal pressures, gauged through alterations in disc morphology and physical stress.Aims
Methods
We evaluated the top 13 journals in trauma and
orthopaedics by impact factor and looked at the longer-term effect regarding
citations of their papers. All 4951 papers published in these journals during 2007 and 2008
were reviewed and categorised by their type, subspecialty and super-specialty.
All citations indexed through Google Scholar were reviewed to establish
the rate of citation per paper at two, four and five years post-publication.
The top five journals published a total of 1986 papers. Only three
(0.15%) were on operative orthopaedic surgery and none were on trauma.
Most (n = 1084, 54.5%) were about experimental basic science. Surgical
papers had a lower rate of citation (2.18) at two years than basic science
or clinical medical papers (4.68). However, by four years the rates
were similar (26.57 for surgery, 30.35 for basic science/medical),
which suggests that there is a considerable time lag before clinical
surgical research has an impact. We conclude that high impact journals do not address clinical
research in surgery and when they do, there is a delay before such
papers are cited. We suggest that a rate of citation at five years
post-publication might be a more appropriate indicator of importance
for papers in our specialty. Cite this article:
Mesenchymal stem-cell based therapies have been
proposed as novel treatments for intervertebral disc degeneration,
a prevalent and disabling condition associated with back pain. The
development of these treatment strategies, however, has been hindered
by the incomplete understanding of the human nucleus pulposus phenotype
and by an inaccurate interpretation and translation of animal to
human research. This review summarises recent work characterising
the nucleus pulposus phenotype in different animal models and in
humans and integrates their findings with the anatomical and physiological
differences between these species. Understanding this phenotype
is paramount to guarantee that implanted cells restore the native
functions of the intervertebral disc. Cite this article:
The August 2014 Spine Roundup360 looks at: rhBMP complicates cervical spine surgery; posterior longitudinal ligament revisited; thoracolumbar posterior instrumentation without fusion in burst fractures; risk modelling for VTE events in spinal surgery; the consequences of dural tears in microdiscectomy; trends in revision spinal surgery; radiofrequency denervation likely effective in facet joint pain and hooks optimally biomechanically transition posterior instrumentation.
