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The aim of this study was to determine the accuracy of specimen-specific finite element models of untreated and cement-augmented vertebrae by direct comparison with experimental results. Eleven single cadaveric vertebrae were imaged using micro computed tomography (microCT) and tested to failure in axial compression in the laboratory. Four of the specimens were first augmented with PMMA cement to simulate a prophylactic vertebroplasty. Specimen-specific finite element models were then generated using semi-automated methods. An initial set of three untreated models was used to determine the optimum conversion factors from the image data to the bone material properties. Using these factors, the predicted stiffness and strength were determined for the remaining specimens (four untreated, four augmented). The model predictions were compared with the corresponding experimental data. Good agreement was found with the non-augmented specimens in terms of stiffness (root-mean-square (r.m.s.) error 12.9 per cent) and strength (r.m.s. error 14.4 per cent). With the augmented specimens, the models consistently overestimated both stiffness and strength (r.m.s. errors 65 and 68 per cent). The results indicate that this method has the potential to provide accurate predictions of vertebral behaviour prior to augmentation. However, modelling the augmented bone with bulk material properties is inadequate, and more detailed modelling of the cement region is required to capture the bone-cement interactions if the models are to be used to predict the behaviour following vertebroplasty. [ABSTRACT FROM AUTHOR]

Introduction:: The Rating Scale for Countertransference (RSCT) - originally, Escala para Avaliação de Contratransferência (EACT) - is a self-administered instrument comprising questions that assess 23 feelings (divided into three blocs, closeness, distance, and indifference) that access conscious countertransferential emotions and sentiments. This paper describes the process of translation and cross-cultural adaptation of the RSCT into American English., Methods:: This study employed the guidelines proposed by the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) Task Force for Translation and Cultural Adaptation which define 10 steps for translation and cross-cultural adaptation of self-report instruments. Additionally, semantic equivalence tools were employed to select the final versions of terms used. The author of the RSCT gave permission for translation and took part in the process. The instrument is available for use free of charge., Results:: Analysis of the back-translation showed that just seven of the 23 terms needed to be adjusted to arrive at the final version in American English., Conclusions:: This study applied rigorous standards to construct a version of the RSCT in American English. This version of the RSCT translated and adapted into American English should be of great use for accessing and researching countertransferential feelings that are part of psychodynamic treatment.

Chronic low back pain is extremely common with a life time prevalence estimated at greater than 70%. Facet joint arthrosis is thought to be the causative aetiological substrate in approximately 25% of chronic low back pain cases. Facet joint injection is a routine intervention in the armamentarium for both the diagnostic and therapeutic management of chronic low back pain. In fact, a study by Carrino et al. reported in excess of 94,000 facet joint injection procedures were carried out in the US in 1999. Although generally considered safe, the procedure is not entirely without risk. Complications including bleeding, infection, exacerbation of pain, dural puncture headache, and pneumothorax have been described. We report a rare case of a 47-year-old female patient who developed a left L4/5 facet septic arthrosis with an associated subdural empyema and meningitis following facet joint injection. This case is unique, as to the best of our knowledge no other case of subdural empyema following facet joint injection has been reported in the literature. Furthermore this case serves to highlight the potential serious adverse sequelae of a routine and apparently innocuous intervention. The need for medical practitioners to be alert to and respond rapidly to the infective complications of facet joint injection cannot be understated., (Copyright © 2016 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.)

Background Context: Percutaneous vertebroplasty has become a favored treatment option for reducing pain in osteoporotic patients with vertebral compression fractures (VCFs). Short-term results are promising, although longer-term complications may arise from accelerated failure of the adjacent vertebral body., Purpose: To provide a preliminary biomechanical assessment of prophylactic vertebral reinforcement adjacent to vertebroplasty using a three-vertebra cadaveric segment under dynamic loads that represent increasing activity demands. In addition, the effects of reducing the elastic modulus of the cement used in the intact vertebrae were also assessed., Study Design/setting: Three-vertebra cadaveric segments were used to evaluate vertebroplasty with adjacent vertebral reinforcement as an intervention for VCFs., Methods: Nine human three-vertebra segments (T12-L2) were prepared and a compression fracture was generated in the superior vertebrae. Vertebroplasty was performed on the fractured T12 vertebra. Subsequently, the adjacent intact L1 vertebra was prophylactically augmented with cement of differing elastic moduli (100-12.5% modulus of the base cement value). After subfailure quasi-static compression tests before and after augmentation, these specimens were subjected to an incrementally increasing dynamic load profile in proportion to patient body weight (BW) to assess the fatigue properties of the construct. Quantitative computed tomography assessments were conducted at several stages in the experimental process to evaluate the vertebral condition and quantify the gross dimensions of the segment., Results: No significant difference in construct stiffness was found pre- or postaugmentation (t=1.4, p=.19). Displacement plots recorded during dynamic loading showed little evidence of fracture under normal physiological loads or moderate activity (1-2.5x BW). A third of the specimens continued to endure increasing load demands and were confirmed to have no fracture after testing. In six specimens, however, greater loads induced 11 fractures: 7 in the augmented vertebra (2xT12, 5xL5) and 4 in the adjacent L2 vertebra. A strong correlation was observed between the subsidence in the segmental unit and the incidence of fracture after testing (r(Spearman's)=-0.88, p=.002). Altering the modulus of cement in the intact vertebra had no effect on level of segmental compromise., Conclusions: These preliminary findings suggest that under normal physiological loads associated with moderate physical activity, prophylactic augmentation adjacent to vertebroplasty showed little evidence of inducing fractures, although loads representing more strenuous activities may generate adjacent and peri-augmentation compromise. Reducing the elastic modulus of the cement in the adjacent intact vertebrae appeared to have no significant effect on the incidence or location of the induced fracture or the overall height loss of the vertebral segment.

Object: The vertebral column is the most common site for secondary bone metastases and lesions arising from hematological malignancies such as multiple myeloma (MM). These infiltrations can be lytic in nature and cause severe weakening of the vertebral body, an increased risk of fracture, and spinal cord compression leading to neurological deficit. Qualitatively it is apparent that increasing infiltration of these lytic lesions will have a deleterious effect on the mechanical behavior of the vertebrae. However, there is little quantitative information about the relationship between tumor deposits and the impact on the mechanical behavior of the vertebrae. In addition, there have been limited biomechanical assessments of the use of vertebroplasty in the management of these malignancies. The purpose of this preliminary study was to evaluate the mechanical behavior of lesion-infiltrated vertebrae from 2 malignant cancers and to investigate the effectiveness of vertebroplasty with and without tumor debulking., Methods: Individual vertebrae from 2 donor spines--one with MM and another with bone metastases secondary to bladder cancer-were fractured under an eccentric flexion load, from which failure strength and stiffness were derived. Alternate vertebrae defined by spinal level were assigned to 2 groups: Group 1 involved removal of lesion material with Coblation (ArthroCare Corp.) preceding vertebroplasty; Group 2 received no Coblation prior to augmentation. All vertebrae were fractured postaugmentation under the same loading protocol. Micro-CT assessments were undertaken to investigate vertebral morphology, fracture patterns, and cement distribution., Results: Multiple myeloma involvement was characterized by several small lesions, severe bone degradation, and multiple areas of vertebral shell compromise. In contrast, large focal lesions were present in the vertebrae with metastatic bladder cancer, and the shell generally remained intact. The mean initial failure strength of the vertebrae with metastases secondary to MM was significantly lower than in vertebrae with bone metastases secondary to bladder cancer (Load = 950 +/- 300 N vs 2200 +/- 750 N, p < 0.0001). A significant improvement in relative fracture strength was found postaugmentation for both lesion types (1.4 +/- 0.5, p < 0.001). Coblation provided a marginally significant increase in the same parameter postaugmentation (p = 0.08) and qualitatively improved the ease of injection and guidance of cement., Conclusions: In the vertebral column, metastatic lesions secondary to bladder cancer and MM showed variations in the pattern of infiltration, both of which led to significant reductions in fracture strength. Account should be taken of these differences to optimize the vertebroplasty intervention in terms of the cement formulation, delivery, and any additional surgical procedure.

Object: The purpose of the study was to investigate the segmental effects of prophylactic vertebroplasty under increasingly demanding loading conditions and to assess the effect of altered cement properties on the construct biomechanics., Methods: Twelve human cadaveric 3-vertebral functional spinal units (T12-L2) were prepared such that the intact L-1 vertebra was prophylactically augmented with cements of differing elastic moduli (100, 50, 25, and 12.5% modulus of the base cement). These specimens were subjected to quasistatic subfailure compression pre- and postaugmentation to 50% of the predicted failure strength and then cyclic loading in a fatigue rig (115,000 cycles) to characterize the high-stress, short-cycle fatigue properties of the construct. Loading was increased incrementally in proportion to body weight to a maximum of 3.5 x body weight. Quantitative computed tomography assessment was conducted pre- and postaugmentation and following cyclic testing to assess vertebral condition, cement placement, and fracture classification., Results: Adjacent and periaugmentation fractures were induced in the prophylactically augmented segments. However, it appeared that these fractures mainly occurred when the specimens were subjected to loads beyond those that may commonly occur during most normal physiological activities., Conclusions: Lowering the elastic modulus of the cement appeared to have no significant effect on the frequency or severity of the induced fracture within the vertebral segment.