Aim

Many aspects of the surgical treatment of patients with tuberculosis (TB) of the spine, including the use of instrumentation and the types of graft, remain controversial. Our aim was to report the outcome of a single-stage posterior procedure, with or without posterior decompression, in this group of patients.

Methods

In this study of patients who underwent internal fixation without fusion for a burst thoracolumbar or lumbar fracture, we compared the serial changes in the injured disc height (DH), and the fractured vertebral body height (VBH) and kyphotic angle between patients in whom the implants were removed and those in whom they were not. Radiological parameters such as injured DH, fractured VBH and kyphotic angle were measured. Functional outcomes were evaluated using the Greenough low back outcome scale and a VAS scale for pain.

Purpose

Angiogenesis and osteogenesis are essential for bone growth, fracture repair, and bone remodeling. VEGF has an important role in bone repair by promoting angiogenesis and osteogenesis. In our previous study, endothelial progenitor cells (EPCs) promoted bone healing in a rat segmental bone defect as confirmed by radiological, histological and microCT evaluations (Atesok, Li, Schemitsch 2010); EPC treatment of fractures resulted in a significantly higher strength by biomechanical examination (Li, Schemitsch 2010). In addition, cell-based VEGF gene transfer has been effective in the treatment of segmental bone defects in a rabbit model (Li, Schemitsch et al 2009); Purpose of this study: Evaluation of VEGF gene expression after EPC local therapy for a rat segmental bone defect.

Background: Prior studies identified that crash severity (Delta V), occupant position, and restraint systems as reliable predictors of crash injuries.1–5 Others have noted that correlation between the biomedical thresholds (age, gender, height, weight) and injury pattern to the lower extremity but very little have been written on the subject of upper extremity.

METHOD: This is a retrospective analysis of CIREN database in a level trauma center focusing on upper extremity injuries. The aim was to investigate the relationship between of the ‘crash’ and ‘occupant’ factors on the pattern and severity of upper extremity injuries following a frontal impact collision. results &

Discussion:Majority of the injuries were soft tissues type. (67.6% soft tissue vs. 32.4% fractures). There were 144 fractures to the upper extremity, 12.5% were ‘open’ fractures. 66% of cases of fractures required operative intervention. 74.5% of the fractures sustained in the upper extremity occurred distal to the elbow, whereas soft tissue injuries predominated in the humerus. 21.5% of distal radius fractures were attributed to airbag deployment and all of the clavicle fractures were related to compression from seat belt. Occupants who sustained fractures had a significantly higher ISS scores (mean score 21.88 vs. 17.68, p < 0.05). Using logistic binary regression model, the ISS continued to be a significant predictor for fracture, overriding weight as a co-founding variable. Of the 144 fractures, 66% of cases required operative intervention.

Conclusion:. To advance occupant protection, it is important to understand the differences in individual variability in affecting injury tolerance in high-energy trauma. One could argue that current modern restraint systems are not designed to protect these vulnerable areas; therefore it may not come as a surprise to observe such an emerging trend of injuries to the upper extremities. There is no doubt that modern restraint systems have contributed to the overall decrease in mortality over the years. However, there are case series reported on the effect of airbag-related injuries to upper extremities as a consequence of its primary effectiveness. Our study reinforce the debate for a more ‘depowered’ airbag capable of saving lives yet simultaneously protecting the upper extremities from serious injuries.

Introduction: Over the last three years, we have demonstrated the complex role of melatonin, a hormone produces mainly in the brain, in the development of scoliosis and in particular by reporting for the first time that cells from AIS patients cannot respond to melatonin, which contrasted with similar cells isolated from healthy subjects. We have determined that this phenomenon is caused by chemical modifications affecting the activity of Gi proteins, a group of small proteins normally associated with both melatonin receptors. Interestingly, previous studies showed that melatonin deficiency could also induce a scoliosis suggesting that the asymmetrical growth of the spine in humans and in melatonin deficient animals could be caused by a common downstream effector regulated by melatonin. This study was then designed to determine and characterise the early biochemical, cellular and molecular changes underlying the formation of spinal deformities in growing pinealectomized chicken and in bipedal C57Bl/6 mice, a naturally melatonin deficient strain of mice.

Methods: For this study, 145 newly hatched chickens (Mountain Hubbard) were purchased at a local hatchery and divided into three distinct groups. First group, pinealectomized (n=100), underwent complete removal of the pineal gland. The second group, sham (n=20), underwent superficial cranial incision without the ablation of the pineal gland. The third group, control (n=25), the chickens did not undergo any surgical procedure. All surgeries were performed by the same surgeon between day three and five after hatching. At days 14, 21 and 28 chicken underwent radiographic examination with a DEXA bone densitometer (PIXImus II, Lunar Corp., Madison, WI). Each digital image was evaluated for the presence of scoliosis and the degree of curvature was measured. Cobb angle threshold value of 10° and higher was retained as a significant scoliotic condition. Blood samples (1 to 2 ml) were taken from a peripheral wing vein of each chicken (from 6 am to 9 am) at the age of 14, 21 and 28 days. Sera were collected by centrifugation and immediately stored at −80°C until assayed. Serum melatonin concentrations were determined using an ELISA method (IBL, Hamburg, Germany). At day 28, chicken were euthanised and tissues were collected to extract mRNA for expression analysis or proteins for subsequent detection. C57Bl/6 mice (n=50) were purchased from Charles-Rivers and bipedal mice were generated by removing the forelimbs and tail after weaning (three weeks old) according to a protocol approved by our institutional animal health care committee. Sera of AIS patients and matched healthy controls were also analysed to determine the levels of circulating P factor using an ELISA assay.

Results: Our results demonstrated a more dynamic variation of circulating melatonin level only in pinealectomised chicken developing a scoliosis, which allowed us to separate scoliotic chicken in two distinct groups. In the first group, the animals showed a biphasic response with a strong decrease of melatonin level between days 14 to 21, followed by a rapid recovery to almost reach the normal values at day 28. In the second group, pinealectomised chickens showed a linear decrease of circulating melatonin over the three-week period while, non-scoliotic pinealectomised chicken showed non-significant variations in melatonin concentration with values close to those obtained with the shams. At the molecular level, expression analysis demonstrated higher expression of a gene encoding a protein that has been termed P factor only in paraspinal muscles of pinealectomized chicken developing a scoliosis. Accumulation of P factor was also confirmed at the protein level by Western blot analysis. Bipedal C57Bl/6 mice, which are naturally melatonin deficient, developed also scoliotic deformities in a proportion of 45% over a two-month period. Interestingly, we observed that genetically modified mice devoid of P factor (n=60) or one of its receptor (n=40) in the same genomic background (C57Bl/6) cannot develop a scoliosis in the same conditions. Moreover, P factor circulating levels in scoliotic patients showed a 2–4 fold increase when compared to healthy matched individuals.

Conclusions: These results showed for the first time a more dynamic variation in circulating melatonin levels among pinealectomised chicken, which was unsuspected by previous studies. Interestingly, a transient decrease of circulating melatonin level was sufficient to induce scoliotic deformities during the first two weeks even if melatonin concentration was subsequently recovered a week later. This may explain why melatonin injection in pinealectomised chicken is not always efficient in preventing scoliosis. Taken together, these observations further suggest that a melatonin decrease below a certain threshold during a specific postnatal window may be sufficient to trigger a scoliosis and reconcile the data concerning AIS patients showing in most of the studies no significant variation when analysed at late stages. The study of early molecular changes in animal models also led us to identify a novel factor, which appears essential to initiate scoliosis through a specific signalling action. The clinical relevance of the P factor in AIS and related spinal syndromes is further strengthened by the detection of high levels of P factor only in scoliotic patients and could pave the way for the development of innovative diagnosis tools as well as the first pharmacological treatments to prevent scoliosis deformities in children.

Research project supported by La Fondation Yves Cotrel de l’Institut de France

The aim of this study was to analyse compressive injuries to the lower limb with data obtained from crash reconstruction to examine injury mechanics (IM’s) and aid car safety.

Prospectively gathered injury and crash reconstruction data were examined from drivers sustaining femoral and/or acetabular fractures (including hip dislocations) following frontal collisions. There were 23 femoral fractures, 21 acetabular and 4 patients with combined femoral and acetabular fractures. It was hypothesised that different IM’s accounted for the relative exclusivity in injury distribution.

There were no statistically significant differences between the two groups with regards to age, weight, height, injury severity scores (ISS) and the relative velocity of impact (mean of 32 and 26mph for femoral and acetabular fractures respectively). Damage to the knee bolster on the side of injury was evident in 21 femoral fractures (1 car burnt out) and 18 acetabular (1 car burnt out). Females were more likely to sustain a femoral fracture than males (71% versus 45%).

Femoral and acetabular fractures do appear to be the result of compressive loadings to the femur as evident by damage to the knee bolsters. Both fracture types arise from low velocity impacts but the IM’s appear different. The driving position of females or their anthropomorphic differences may account for their higher propensity for femoral injury. The deployment of an airbag while not wearing a seatbelt may cause the occupant to ‘submarine’ beneath the airbag. Subsequent impact of the knee against the bolster may impart different energy loading characteristics to the femur to that of belted occupants. Knee bolster design may thus be of importance in injury modification. Assuming that acetabular fractures are associated with greater morbidity than femoral fractures, these data further support the advice that seatbelts be worn.