Surgical procedure and initial radiographic results of a new augmentation technique for vertebral compression fractures

Purpose

Recently, a new minimally invasive technique called ‘vertebral body stenting’ (VBS) was introduced for the treatment of osteoporotic vertebral fractures. The technique was developed to prevent the loss of reduction after deflation of the balloon and to reduce the complication rate associated with cement leakage.

Methods

The amount of kyphosis correction, improvement of vertebral body height and quantitative cement leakage rate by applying CT-based quantitative volumetry after VBS were measured in 27 patients (55 vertebra) and compared with a control group (29 patients, 61 vertebrae), which was treated with conventional vertebroplasty.

Results

After VBS, a significant improvement was seen in vertebral height, compared to conventional vertebroplasty. The mean improvement in segmental kyphosis and vertebral kyphosis were 5.8° (p < 0.05) and 3.5° (p < 0.05), respectively. In the VBS group, the mean injected volume of cement per vertebral body was 7.33 cm³ (3.34–10.19 cm³). The average amount of cement outside the vertebrae was 0.28 cm³ (0.01–1.64 cm³), which was 1.36 % of the applied total cement volume. In the vertebroplasty group, the applied mean volume of the cement per level was 2.7 cm³ (1–5.8 cm³) and the average amount of cement outside the vertebrae was 0.15 cm³ (0.01–1.8 cm³), which was 11.5 % (0.2–60 %) of the applied total volume of cement.

Conclusion

The frequency of cement leakage after VBS was 25.5 % compared to 42.1 % in the vertebroplasty group. VBS led to a significant decrease in the leakage rate compared with conventional vertebroplasty.     

Footprint mismatch in total cervical disc arthroplasty

Purpose

Cervical disc arthroplasty has become a commonplace surgery for the treatment of cervical radiculopathy and myelopathy. Most manufacturers derive their implant dimensions from early published cadaver studies. Ideal footprint match of the prosthesis is essential for good surgical outcome.

Methods

We measured the dimensions of cervical vertebrae from computed tomography (CT) scans and to assess the accuracy of match achieved with the most common cervical disc prostheses [Bryan (Medtronic), Prestige LP (Medtronic), Discover (DePuy) Prodisc-C (Synthes)]. A total of 192 endplates in 24 patients (56.3 years) were assessed. The anterior–posterior and mediolateral diameters of the superior and inferior endplates were measured with a digital measuring system.

Results

Overall, 53.5 % of the largest device footprints were smaller in the anterior–posterior diameter and 51.1 % in the mediolateral diameter were smaller than cervical endplate diameters. For levels C5/C6 and C6/C7 an inappropriate size match was noted in 61.9 % as calculated from the anteroposterior diameter. Mismatch at the center mediolateral diameter was noted in 56.8 %. Of the endplates in the current study up to 58.1 % of C5/C6 and C6/C7, and up to 45.3 % of C3/C4 and C4/C5 were larger than the most frequently implanted cervical disc devices.

Conclusion

Surgeons and manufacturers should be aware of the size mismatch in currently available cervical disc prostheses, which may endanger the safety and efficacy of the procedure. Undersizing the prosthetic device may lead to subsidence, loosening, heterotopic ossification and biomechanical failure caused by an incorrect center of rotation and load distribution, affecting the facet joints.     

Penumbra around chronic cerebral infarction?

In a series of 13 patients with cerebrovascular occlusive disease regional cerebral blood flow (rCBF) measurements (two-dimensional intravenous ¹³³Xe clearance method) and quantitative EEG analysis (sensorimotor rhythms) as well as electronic measurement of handforce were performed before and during intravenous infusion of 1 μg kg/min of one of the lipophilic dihydropyridine calcium channel blocker nimodipine (Nimotop®). The aim of the study was to test the hypothesis of the existence of hypoperfusion (ischaemic penumbra) in the surroundings of chronic cerebral infarcts. All 3 parameters improved in one patient. Sensorimotor rhythms increased in 5 patients, rCBF in 3. EEG and rCBF improved in 2 patients. In 3 instances, a redistribution of rCBF in favour of the peri-infarct zone was noted (significant increase of rCBF from 35 ± 2 sem to 53 ± 4 ml/100 g/min (p > 0.01), whereas rCBF fell from 61 ± 5 to 46 ±2 ml/100 g/min on a collimator remote from the infarct but in the infarcted hemisphere. The parallel improvement of rCBF and EEG in brain regions surrounding chronic infarcts in 3 patients was interpreted as functional improvement as a consequence of nimodipine-induced normalization of peri-infarct hypoperfusion, i.e. reversal of flow-dependent neuronal silence and/or dysfunction.     

Microglial activation and expression of immune‐related genes in a rat ex vivo nervous system model after infection with Listeria monocytogenes

A wide variety of microorganisms has previously been identified as causes of brain infection. Among them, Listeria monocytogenes has a particular tropism for the central nervous system. To gain knowledge about the immune response elicited by L. monocytogenes in the brain, we used a rat ex vivo organotypic nervous system culture as a model for Listeria infection. Scanning electron microscopy (SEM) revealed that activated microglial cells showing a typical amoeboid morphology are quickly recruited to the surface of the explants after the infection. After bacterial engulfment, these cells appear to act as Trojan horses, releasing the engulfed bacteria inside the brain tissue. We describe cycles of microglial phagocytosis, necrotic cell death and the subsequent removal of cell debris for the first time. Furthermore, we used this ex vivo model to assess the expression profiles of immune relevant genes up to 24 h postinfection by means of q‐PCR‐arrays, finding that a number of inflammation‐promoting genes are upregulated. Shortly after infection by L. monocytogenes, upregulated genes were those that encoded molecules involved in Th1 responses, being the Ccl2 chemokine and members of the interleukin1‐β family the most abundant immunomodulatory signals expressed. After 5 h of infection, L. monocytogenes caused a substantial increase in the expression of TLR1 and TLR2 genes, as well as in several downstream genes of the TLR signaling pathways. © 2013 Wiley Periodicals, Inc.     

Main lymphocyte subpopulations in cerebrospinal fluid and peripheral blood in HIV-1 subtypes C and B

Journal of NeuroVirology - HIV-1 subtype C (HIV-1C) shows reduced Tat protein chemoattractant activity compared with HIV-1B. The impact of HIV-1C Tat on the chemotaxis of the main lymphocyte...     

Prevention of parastomal hernias with 3D funnel meshes in intraperitoneal onlay position by placement during initial stoma formation

Purpose

In patients with terminal ostomies, parastomal hernias (PSHs) occur on a frequent basis. They are commonly associated with various degrees of complaints and occasionally lead to life-threatening complications. Various strategies and measures have been tested and evaluated, but to date there is a lack of published evidence with regard to the best surgical technique for the prevention of PSH development.

Methods

We conducted a retrospective analysis of prospectively collected data of eighty patients, who underwent elective permanent ostomy formation between 2009 and 2014 by means of prophylactic implantation of a three-dimensional (3D) funnel mesh in intraperitoneal onlay (IPOM) position.

Results

PSH developed in three patients (3.75 %). No mesh-related complications were encountered and none of the implants had to be removed. Ostomy-related complications had to be noted in seven (8.75 %) cases. No manifestation of ostomy prolapse occurred. Follow-up time was a median 21 (range 3–47) months.

Conclusion

The prophylactical implantation of a specially shaped, 3D mesh implant in IPOM technique during initial formation of a terminal enterostomy is safe, highly efficient and comparatively easy to perform. As opposed to what can be achieved with flat or keyhole meshes, the inner boundary areas of the ostomy itself can be well covered and protected from the surging viscera with the 3D implants. At the same time, the vertical, tunnel-shaped part of the mesh provides sufficient protection from an ostomy prolapse. Further studies will be needed to compare the efficacy of various known approaches to PSH prevention.

     

Influence of Probiotics Administration Before Liver Resection in Patients with Liver Disease: A Randomized Controlled Trial

World Journal of Surgery - By inhibiting the growth of pathogenic bacteria and modulating the local intestinal immune system, probiotics may reduce bacterial translocation and systemic...