Auto-Decompression - Preserved Neurological Function in Bilateral Cervical Facet Dislocations

Introduction Bilateral cervical facet dislocation (BCFD) is an uncommon injury with a high incidence of severe neurological impairment. We describe 4 cases of BCFD with preserved neurological function. Cases Case 1: A 78-year-old female who suffered two ground level falls (GLFs). Pre-operative American Spinal Injury Association (ASIA) Score was C5D. Imaging revealed a BCFD at C6/C7 and a C6 laminar fracture. Case 2: A 63-year-old male suffered a fall down 14 steps. Pre-operative ASIA score was E. Imaging demonstrated a BCFD at C7/T1, and a C6 laminar fracture. Case 3: A 46-year-old male collided with a tree while descending a hill on a bicycle. Pre-operative ASIA score was C6D. Imaging revealed a BCFD at C7/T1 and a C7 laminar fracture. Case 4: A 67-year-old male suffered a GLF while exiting a stationary car. Pre-operative ASIA score on admission was E. Imaging revealed a BCFD at C6/C7 with bilateral laminar fractures at C5 and C6. Outcome All cases underwent 2-stage surgical fixation. All cases maintained or had an improved ASIA score post-operatively. Conclusion In all cases, the presence of concurrent laminar fractures resulted in an auto-decompression of the spinal canal, preserving neurological function.

Degenerative tears of the posterior horn of the medial meniscus: correlation between MRI findings and outcome following intra-articular steroid/bupivacaine injection of the knee.

AIM: To evaluate the response of symptomatic degenerative tears of the posterior horn of the medial meniscus to guided intra-articular knee steroid/bupivacaine injection and to correlate clinical outcomes with preprocedural findings at magnetic resonance imaging (MRI). MATERIALS AND METHODS: Sixty patients who had clinical and MRI evidence of a symptomatic degenerative tear of the posterior horn of the medial meniscus, isolated or accompanied by additional features of degenerative arthritis, who had failed conservative approaches (physiotherapy, non-steroidal anti-inflammatories, and 3 months rest/knee bracing) were included in the study. Patients underwent intra-articular knee steroid/bupivacaine injection and were followed clinically for a minimum of 6 months. Preprocedural MRI findings were correlated with duration of symptoms, clinical response to injection (recorded as complete, partial or no response) and duration of response to injection. RESULTS: Forty-nine of 60 patients (82%) reported an improvement in symptoms following guided intra-articular knee steroid/bupivacaine injection (complete: 25 patients (42%), partial: 24 (40%) patients). Improvement was sustained in 32 of 60 patients (53%) at follow-up. Thirteen of 18 patients (72%) who had an isolated degenerative tear of the posterior horn of the medial meniscus recorded a complete resolution of symptoms. This was sustained at follow-up in 10 patients (56%). CONCLUSION: Intra-articular steroid/bupivacaine knee joint injection reduced pain symptoms in the majority of patients (81.7%) with degenerative tears of the posterior horn of the medial meniscus, usually with a sustained response. Preprocedural MRI appearances correlate with response to injection. Patients with isolated tears are more likely to have a favourable outcome.

Differing MRI appearances of symptomatic proximal hamstring tendinopathy with ageing: a comparison of appearances in patients below and above 45 years.

AIM: To compare magnetic resonance imaging (MRI) appearances of symptomatic proximal hamstring tendinopathy (PHT) in younger (<45 years) and older (>45 years) patients. MATERIALS AND METHODS: MRI of patients with symptomatic PHT were reviewed and compared to asymptomatic age- and sex-matched controls. Appearances recorded were as: type 0, normal tendon; type I, intra-substance signal abnormality; type II, ischial bone and soft-tissue oedema with/without type I findings; type III, curvilinear fluid signal tearing with/without type II findings; type IV, bony avulsion. Disease pattern was compared between age groups using Fisher's exact test. RESULTS: Thirty-one symptomatic patients (18 male, 13 female; mean age 42 years) were identified. Imaging findings of 16 patients >45 years, 15 patients <45 were as follows: type 0 n=8, type I n=7, type II n=6, type III n=10, type IV n=0. Those >45 years tended to have type III tendinopathy, no examples of type III disease were found in patients <45 years (p<0.001). No significant difference in disease pattern was seen between males and females (p=0.39). Seven of 31 controls >45 years had type III findings and four controls <45 years had type I findings. CONCLUSION: MRI appearances of symptomatic PHT differ with age. Differences may reflect mechanism, whereby overuse-related micro-tearing of healthy tendons occurs in young patients versus degenerative tendinopathy in older patients. Abnormal tendon appearances in patients >45 years may or may not be symptomatic. In contrast, abnormalities identified in younger patients are generally symptomatic. These described differences are important in the primary diagnosis and may impact upon patient response to therapy.

Calcification Volume Reduces Stretch Capability and Predisposes Plaque to Rupture in an in vitro Model of Carotid Artery Stenting.

OBJECTIVE/BACKGROUND: Carotid artery stenting (CAS) in calcified arteries carries a higher peri-operative risk. This study investigates the relationship between the stretching limits of carotid plaque samples and calcification in order to determine a stretch tolerance criterion for endovascular intervention. METHODS: Seventeen carotid plaque samples were acquired from standard endarterectomy procedures. The maximum stretch capability of the global plaque was determined by circumferentially extending the tissue to complete failure. Quantitative assessment of calcification was performed using high resolution computed tomography, including measures of percent calcification volume fraction (%CVF) and calcification configuration. Maximum stretch properties were then related to calcification measures in order to evaluate the predictive power of calcification for determining plaque stretching limits. RESULTS: A strong negative correlation was found between %CVF and stretch ratio with respect to specific calcification configuration types. All plaques with < 70% stenosis superseded the minimum required stretch threshold. Severe stenosis (> 70%) warrants a stretch of at least 2.33 during revascularisation and only plaques containing concentric calcifications with < 20% CVF successfully reached this minimum required stretch threshold. CONCLUSION: The addition of calcification measures to the stenosis classification may help in guiding endovascular intervention techniques to achieve a balance between an acceptable residual patency level while avoiding plaque rupture in calcified carotid plaques.

A role for susceptibility weighted imaging in progressive multifocal leukoencephalopathy.

We report a radiologic finding on magnetic resonance imaging (MRI) of the brain of two cases of progressive multifocal leukoencephalopathy (PML) of hypointense signal of subcortical U-fibres on susceptibility weighted (SW) sequence. The first case is a 50-year-old man recently treated with chemotherapy including rituximab for non-Hodgkin's lymphoma. The second case is a 64-year-old woman with human immunodeficiency virus (HIV) infection. Iron deposition is a likely causative factor. We propose that SWI may be especially useful in the assessment of indeterminate cases to reduce the likelihood of a missed diagnosis of PML.

Pre-Hospital Fast Positive Cases Identified by DFB Ambulance Paramedics: Final Clinical Diagnosis.

Ischaemic stroke clinical outcomes are improved by earlier treatment with intravenous thrombolysis. An existing pathway at the Mater University Hospital for assessment of suspected acute stroke in the Emergency Department was updated, aiming to shorten door-to-needle time. This study examines the final clinical diagnosis of Dublin Fire Brigade Ambulance Paramedic identified Face-Arm-Speech-Test (FAST) positive patients presenting to the Emergency Department over a 7 month period. A retrospective analysis was carried out of 177 consecutive FAST positive patients presenting between March and November 2014. The final clinical diagnosis was acute stroke in 57.1% (n=101) of patients. Of these, 76 were ischaemic strokes of whom 56.5% (n=43) were thrombolysed. In the pre-hospital setting Ambulance Paramedics can identify, with reasonable accuracy, acute stroke using the FAST test. Over half of the ischaemic stroke patients presenting via this pathway can be treated with intravenous thrombolysis.

Comparison of four chondral repair techniques in the hip joint: a biomechanical study using a physiological human cadaveric model.

OBJECTIVE: The objective of this study was to assess the biomechanical stability of three types of chondral flap repair techniques as well as a hydrogel scaffold implantation on the acetabular articular surface using a physiological human cadaveric model. METHODS: Chondral flaps were created in the antero-superior zone of the acetabulum in a series of human cadaveric hip joints. The chondral flap was repaired by fibrin glue, cyanoacrylate, suture technique and an agarose hydrogel scaffold sealed with fibrin glue using six hips in each case. After each repair, the specimens were mounted in a validated jig and tested for 1500 gait cycles. In order to determine the stability of the repair, specimens were evaluated arthroscopically at specific intervals. RESULTS: The fibrin glue and cyanoacrylate techniques were technically the easiest to perform arthroscopically, all flaps repaired with fibrin were detached at 50 cycles while those repaired with cyanoacrylate lasted for an average of 635 cycles. On the other hand, both the suture repair and scaffold implantation techniques were more technically challenging but were both stable till the endpoint of 1500 cycles. CONCLUSION: Fibrin glue on its own does not provide sufficient fixation to repair chondral flaps on the acetabular surface. Cyanoacrylate repairs universally failed midway through the testing protocol employed here, raising doubts as to the effectiveness of that technique. The suture and hydrogel scaffold technique were the most reliable for chondral repair at any given cycle. The results of this biomechanical study demonstrate the relative effectiveness of chondral repair and fixation techniques.

Improving surgical site infection prevention practices through a multifaceted educational intervention.

As part of the National Clinical Programme on healthcare-associated infection prevention, a Royal College of Surgeons in Ireland (RCSI) and Royal College of Physicians of Ireland (RCPI) working group developed a quality improvement tool for prevention of surgical site infection (SS). We aimed to validate the effectiveness of an educational campaign, which utilises this quality improvement tool to prevent SSI in a tertiary hospital. Prior to the SSI educational campaign, surgical patients were prospectively audited and details of antibiotic administration recorded. Prophylactic antibiotic administration recommendations were delivered via poster and educational presentations. Post-intervention, the audit was repeated. 50 patients were audited pre-intervention, 45 post-intervention. Post-intervention, prophylaxis within 60 minutes prior to incision increased from 54% to 68% (p = 0.266). Appropriate postoperative prescribing improved from 71% to 92% (p = 0.075). A multifaceted educational program may be effective in changing SSI prevention practices.

Diagnostic accuracy of non-radiologist performed ultrasound for abdominal aortic aneurysm: systematic review and meta-analysis.

BACKGROUND: Ultrasonography is increasingly used by clinicians to identify abdominal aortic aneurysms (AAA). We performed a systematic review and meta-analysis comparing the accuracy of non-radiologist performed ultrasound (NRPUS) for AAA disease to the 'gold standard' of radiologist performed aortic imaging (RPI), intra-operative findings or postmortem findings. METHODS: Cochrane Library, MEDLINE, EMBASE, SCOPUS-V.4, trial registries, conference proceedings, and article reference lists were searched to identify studies comparing NRPUS with RPI as the reference standard. Data abstracted from eligible studies was used to generate 2 × 2 contingency tables allowing calculation of pooled sensitivity and specificity values. RESULTS: 11 studies (944 patients) evaluated NRPUS for AAA detection. NRPUS had a pooled sensitivity of 0.975 [95% confidence interval (CI), 0.942-0.992] for AAA detection and a pooled specificity of 0.989 (95% CI, 0.979-0.995). CONCLUSIONS: Non-radiologist performed ultrasound achieves acceptable sensitivity and specificity for both detection and measurement of AAA. There was no evidence of significant heterogeneity with respect to pooled sensitivity or specificity.

A VLU complicated by severe group a streptococcal infection resulting in necrotising fasciitis and septic shock: a case report.

This case study outlines the management of a patient with a venous leg ulcer whose swabs cultured Staphylococcus aureus and beta-haemolytic streptococcus group A while in hospital with cellulitis, which was treated with antibiotics as per sensitivities. However, the patient presented at the emergency department five weeks later with a diagnosis of invasive group A streptococcal disease resulting in necrotising fasciitis and streptococcal toxic shock syndrome. This paper describes the holistic care and wound management that the patient received.

Multifocal giant cell tumor of the tendon sheath: case report and literature review.

In this study, we present the rare case of a patient with a multifocal giant cell tumor of the tendon sheath occurring at three different localizations along the same tendon. We review radiographic, ultrasonographic, and magnetic resonance imaging findings, and discuss previously reported cases.

Double-bundle depiction of the anterior cruciate ligament at 3 Tesla.

INTRODUCTION: Magnetic resonance imaging on 3 Tesla (3T MRI) with arthroscopic correlation has proven to adequately identify the anteromedial bundle (AMB) and posterolateral bundle (PLB) in cadaver knees. The purpose of this study was to describe the depiction of ACL bundle anatomy on 3T MRI in daily practice. METHODS: In a retrospective cohort study, we included 50 consecutive patients who underwent standard 3T MRI of the knee and had an intact ACL. Two musculoskeletal radiologists independently reviewed all scans for depiction of ACL bundle anatomy using standardized forms. Descriptive statistics were used. RESULTS: Twenty-three right knees (46%) and 27 left knees (54%) were included in the study. Mean age of the patients was 35 years (range 12 to 68 years); 37 patients were male (74%). ACL bundle anatomy was best depicted in the axial plane in 44 knees (88%) and in the coronal plane in six knees (12%). Two bundles were seen in 47 knees (94%). The AMB was completely seen in 45 knees (90%). The PLB was completely seen in 40 knees (80%). Both bundles were completely seen in 37 knees (76%). CONCLUSIONS: The double-bundle anatomy of the ACL is visualized in 94% of patients on 3T MRI. Because of potentially associated clinical benefits, we advocate to report separately on the anteromedial bundle and posterolateral bundle in case of anterior cruciate ligament injury of the knee.

Improving patient care--the first year in a dedicated surgical assessment unit.

A surgical assessment unit (SAU) was established in October 2009 at the Mid-Western Regional Hospital. We assessed this servic in its initial year and compared it to Emergency Department (ED) services. We audited SAU and ED databases and theatre logbooks from November 2009 to October 2010. 1949 patients were referred to the SAU and 857 patients were admitted (44%). Only 44 SAU patients (6%) waited more than 6 hours for a bed compared to 828 patients (68%) admitted through the ED. SAU patients who required emergency surgery had a shorter waiting time before theatre (37 (18.6%) vs 9(6%) waited less than 6 hours, p < 0.05). To summarise, we found that almost 2,000 patients who would otherwise have presented to the ED were referred to the SAU. Waiting times for admission and theatre were significantly shorter. Further resource allocation could expand the service and improve it further, by diverting more patients from the ED.

Deep brain stimulation in ireland for Parkinson's disease and essential tremor.

Deep brain stimulation (DBS) is highly effective neurosurgery for idiopathic Parkinson's disease (IPD), essential tremor (ET) and primary dystonia. DBS involves stereotactic surgical implantation of a battery-operated stimulator into deep brain nuclei. Irish patients are referred abroad for DBS and have to travel repeatedly for pre and post-operative care resulting in stress, anxiety and hardship. Safe pre and post-operative care of these complex, ageing patients is compromised by the absence of a DBS service in Ireland. Moreover, both DBS surgery and the subsequent post-operative care abroad incurs substantial cost to the state. The Dublin Neurological Institute at the Mater Misericordiae University Hospital (DNI) is a non-profit institute for the care of patients with neurological diseases. The DNI developed, in collaboration with the Mater Private Hospital (MPH) and the Walton Centre, Liverpool, a DBS programme in 2008/2009. We performed DBS at the Mater Campus on three carefully selected patients from a cohort of movement disorder patients attending the DNI and continue to provide pre-operative assessment and post operative care for patients following DBS in Ireland and abroad.

Three-dimensional magnetic resonance imaging analysis of hip morphology in the assessment of femoral acetabular impingement.

AIM: To determine a possible association between femoral-acetabular impingement (FAI) volume and the development of labral tear using a three-dimensional (3D) model reconstruction of the acetabulum and the femoral head. MATERIALS AND METHODS: Magnetic resonance arthrography images of the hip in 42 patients with pain and suspected labral tear were acquired using a 1.5T MRI machine. Using 3D analysis software, outlines of the acetabular cup and femoral head were drawn and 3D reconstruction obtained. To control for differences in patient size, ratios of acetabulum : femoral head volume (AFV) and acetabulum : femoral head surface area (AFA) were used for analysis. The association between volume of acetabulum : femoral head and FAI was investigated using ANOVA analysis. RESULTS: There were 19 men and 23 women with a mean age of 39 years (range 18-78 years). The average AFV was 0.64 (range 0.37-1.05, SD 0.16) and AFA was 0.73 (range 0.36-1.26, SD 0.23). Herniation pit was significantly associated with a small AFV. CONCLUSION: Femoral neck herniation pits are associated with a low AFV. Gross volume and surface area ratios do not appear to correlate with labral tears or cartilage loss. This technique will enable more advanced analysis of morphological variations associated with FAI.

A computational study of the magnitude and direction of migration forces in patient-specific abdominal aortic aneurysm stent-grafts.

OBJECTIVES: Endovascular aneurysm repair for abdominal aortic aneurysm (AAA) is now a widely adopted treatment. Several complications remain to be fully resolved and perhaps the most significant of these is graft migration. Haemodynamic drag forces are believed to be partly responsible for migration of the device. The objective of this work was to investigate the drag forces in patient-specific AAA stent-grafts. METHODS: CT scan data was obtained from 10 post-operative AAA patients treated with stent-grafts. 3D models of the aneurysm, intraluminal thrombus and stent-graft were created. The drag forces were determined by fluid-structure interaction simulations. A worst case scenario was investigated by altering the aortic waveforms. RESULTS: The median resultant drag force was 5.46 N (range: 2.53-10.84). An increase in proximal neck angulation resulted in an increase in the resultant drag force (p = 0.009). The primary force vector was found to act in an anterior caudal direction for most patients. The worst case scenario simulation resulted in a greatest drag force of 16 N. CONCLUSIONS: Numerical methods can be used to determine patient-specific drag forces which may help determine the likelihood of stent-graft migration. Anterior-posterior neck angulation appears to be the greatest determinant of drag force magnitude. Graft dislodgement may occur anteriorally as well as caudally.

The Presence of a High Peak Feature Within Low-Average Shear Stimuli Induces Quiescence in Venous Endothelial Cells.

Wall shear stress (WSS) is an important stimulus in vascular remodelling and vascular lesion development. The current methods to assess and predict the risk associated with specific unsteady WSS consider the WSS mean values or the presence of reverse phases described by the oscillatory shear index. Recent evidence has shown that the accuracy of these methods is limited, especially with respect to the venous environment. Unsteady WSS are characterised by several features that may individually affect endothelial cells. Consequently, we assessed the effects of averaged WSS (TAWSS), temporal WSS gradient (TWSSG), maximum WSS (WSS peak) and reverse phase (OSI) by applying different WSS profiles to venous EC in-vitro, using a real-time controlled cone-and-plate cell-shearing device for 24 h. We found that TWSSG and WSS peak affect cell elongation and alignment respectively. We also found that the WSS waveforms with a peak of 1.5 Pa or higher significantly correlate with the induction of a protective phenotype. Cell phenotype induced by these high peak waveforms does not correlate to what is predicted by the hemodynamic indices currently used. The definition of reliable hemodynamic indices can be used to inform the computational models aimed at estimating the hemodynamic effects on vascular remodelling.