Evaluation of painful total knee arthroplasty: an approach based on common etiologies for total knee arthroplasty revision

A differential diagnosis with emphasis on the common indications for revision should be utilized in the workup of painful total knee arthroplasty (TKA). The physician should identify the exact etiology of the patient's pain to maximize outcomes from treatment. Evaluation for infection should be completed using the Musculoskeletal Infection Society (MSIS) criteria. When common causes of revision TKA do not appear to be the cause of the pain, less likely causes should be not be ignored. Further advancements such as pressure sensing devices may be able to improve patient satisfaction and decrease the incidence of pain following TKA.

Ultrasound simulation training to meet the 2021 Royal College of Radiologists' curriculum for radiology trainees: South East London experience

AIM

To enhance ultrasound teaching delivery to radiology trainees using a simulation course matched to the 2021 Royal College of Radiologists (RCR) curriculum.

MATERIAL AND METHODS

An ultrasound simulation training course was designed for specialty trainees (ST) 1 in radiology, which was based on the 2021 RCR curriculum and covered the top ultrasound training priorities. The course was piloted initially on two occasions in a 1-day format to the August 2021 and the March 2022 ST1 intake trainees. Based on the feedback, a comprehensive 4-day course was developed and delivered between October and December 2022 for the August 2022 ST1 intake, funded by Health Education England. The outcomes measured were subjective trainee feedback using numerical scores and free text.

RESULTS

All King's College Hospital NHS Foundation Trust radiology ST1 trainees from the August 2021 to the August 2022 intake participated in ultrasound simulation training. The training matched the RCR curriculum and increased the trainees' confidence and competency in medical ultrasound.

CONCLUSIONS

Ultrasound simulation training can be successfully delivered to ST1 trainees to match the 2021 RCR curriculum and enhance training in medical ultrasound for radiologists.

Advanced glycation end-product accumulation differs by location and sex in aged osteoarthritic human menisci

OBJECTIVE

There is a clear link between increasing age and meniscus degeneration, leading to increased injury, osteoarthritis (OA) progression, and often total knee replacement. Advanced glycation end-products (AGEs) are non-enzymatic crosslinks and adducts that accumulate in collagen with age, altering tissue mechanics and cell function, ultimately leading to increased injury and inflammation. AGEs, both fluorescent and non-fluorescent, play a central role in age-related degradation of tissues throughout the body; however, little is known about their role in meniscus degeneration. The objective of this study was to characterize changes in aged OA menisci, specifically evaluating zonal AGE accumulation, to gain a better understanding of changes that may lead to age-related meniscal degeneration.

METHOD

Deidentified human menisci (N = 48, 52-84 years old) were obtained from subjects undergoing total knee replacement. Changes in extracellular matrix (ECM) were assessed by gross morphology, confocal analysis, and biochemical assays. Deoxyribonucleic acid (DNA), glycosaminoglycan (GAG), collagen, and AGE accumulation were compared with patient age, zonal region, and patient sex.

RESULTS

There were minimal changes in DNA, GAG, and collagen concentration with age or zone. However, collagen fraying and AGEs increased with age, with more AGEs accumulating in the meniscal horns compared to the central body and in male menisci compared to females.

CONCLUSIONS

Overall, this work provides greater insights into regional changes that occur in human menisci with age and OA. These results suggest AGEs may play a role in the degeneration of the meniscus, with AGEs being a possible target to reduce age-related tears, degeneration, and OA progression.

Antegrade femoral nailing in the lateral decubitus position: a case series, technical tips and review of literature

BACKGROUND

Femoral intramedullary nailing is traditionally performed with the patient supine on a fracture table. We aimed to describe a case series of femoral intramedullary nailing for fracture in the lateral position, with discussion of the operative technique.

METHODS

A retrospective analysis identified 52 patients who underwent femoral intramedullary nailing performed in a lateral position without traction over a 5-year period at a single level 1 trauma center. Medical records were reviewed for demographics, blood loss including need for transfusion, operative duration, complications, length of stay, fracture union, re-operation and death.

RESULTS

There were 24 subtrochanteric, 16 peri-trochanteric and 12 diaphyseal femoral fractures. Mean operative time was 136.2 ± 101.4 min with a mean estimated blood loss of 372.5 ± 349.6 ml. Seventeen patients required blood transfusion. Mean length of stay was 10.3 ± 8.1 days. There were 3 (5.8%) surgical (compartment syndrome, infection and retained drain) and 12 (23.1%) medical complications, with a 30-day mortality rate of 3.8% (2). Mean follow-up was 9.9 ± 8.7 months. The union rate was 94.2% (49) and 3.8% (2) patients required revision fixation (hardware exchange for irritation and exchange nailing for non-union). Discharge destination was home, rehabilitation center and specialized nursing facility in 21 (40.4%), 16 (30.8%) and 15 (28.8%) patients, respectively.

DISCUSSION AND CONCLUSION

Femoral intramedullary nailing in the lateral decubitus position is a useful technique of managing peri-trochanteric, subtrochanteric and diaphyseal femoral fractures. We describe a known technique with technical tips, which has distinct advantages over traditional supine positioning especially in certain patient and fracture types. In addition, operative times, blood loss, length of stay, revision and outcomes were comparable to the literature.

Transesophageal Echocardiography Guidance for Percutaneous Closure of Ascending Aortic Pseudoaneurysm

• Percutaneous closure of ascending aortic pseudoaneurysms is feasible in selected patients. • Procedural planning with multimodality imaging and multidisciplinary discussion is key. • TEE can be instrumental for intraprocedural guidance. • TEE guidance minimizes the amount of iodinated contrast and ionizing radiation used.

Trends in Utilization of Aortic Valve Replacement for Severe Aortic Stenosis

BACKGROUND

Despite the rapid growth of aortic valve replacement (AVR) for aortic stenosis (AS), limited data suggest symptomatic severe AS remains undertreated.

OBJECTIVES

This study sought to investigate temporal trends in AVR utilization among patients with a clinical indication for AVR.

METHODS

Patients with severe AS (aortic valve area <1 cm²) on transthoracic echocardiograms from 2000 to 2017 at 2 large academic medical centers were classified based on clinical guideline indications for AVR and divided into 4 AS subgroups: high gradient with normal left ventricular ejection fraction (LVEF) (HG-NEF), high gradient with low LVEF (HG-LEF), low gradient with normal LVEF (LG-NEF), and low gradient with low LVEF (LG-LEF). Utilization of AVR was examined and predictors identified.

RESULTS

Of 10,795 patients, 6,150 (57%) had an indication or potential indication for AVR, of whom 2,977 (48%) received AVR. The frequency of AVR varied by AS subtype with LG groups less likely to receive an AVR (HG-NEF: 70%, HG-LEF: 53%, LG-NEF: 32%, LG-LEF: 38%, P < 0.001). AVR volumes grew over the 18-year study period but were paralleled by comparable growth in the number of patients with an indication for AVR. In patients with a Class I indication, younger age, coronary artery disease, smoking history, higher hematocrit, outpatient index transthoracic echocardiogram, and LVEF ≥0.5 were independently associated with an increased likelihood of receiving an AVR. AVR was associated with improved survival in each AS-subgroup.

CONCLUSIONS

Over an 18-year period, the proportion of patients with an indication for AVR who did not receive AVR has remained substantial despite the rapid growth of AVR volumes.

Patient and Provider Risk in Managing ST-Elevation Myocardial Infarction During the COVID-19 Pandemic: A Decision Analysis

BACKGROUND

The optimal treatment strategy for treating ST-segment-elevation myocardial infarction (STEMI) in context of the coronavirus disease 2019 (COVID-19) pandemic is unclear given the potential risk of occupational exposure during primary percutaneous coronary intervention (PPCI). We quantified the impact of different STEMI treatment strategies on patient outcomes and provider risk in context of the COVID-19 pandemic.

METHODS

Using a decision-analytic framework, we evaluated the effect of PPCI versus the pharmaco-invasive strategy for managing STEMI on 30-day patient mortality and individual provider infection risk based on presence of cardiogenic shock, suspected coronary territory, and presence of known or presumptive COVID-19 infection.

RESULTS

For patients with low suspicion for COVID-19, PPCI had mortality benefit over the pharmaco-invasive strategy, and the risk of cardiac catheterization laboratory provider infection remained very low (<0.25%) across all subgroups. For patients with presumptive COVID-19 with cardiogenic shock, PPCI offered substantial mortality benefit to patients relative to the pharmaco-invasive strategy (7.9% absolute decrease in 30-day mortality), but also greater risk of provider infection (2.3% absolute increase in risk of provider infection). For patients with presumptive COVID-19 with nonanterior STEMI without cardiogenic shock, PPCI offered a 0.4% absolute mortality benefit over the pharmaco-invasive strategy with a 0.2% greater absolute risk of provider infection, and the tradeoff between patient and provider risk with PPCI became more apparent in sensitivity analysis with more severe COVID-19 infections.

CONCLUSIONS

Usual care with PPCI remains the appropriate treatment strategy in the majority of cases presenting with STEMI in the setting of the COVID-19 pandemic. However, utilization of a pharmaco-invasive strategy in selected patients with STEMI with presumptive COVID-19 and low likelihood of mortality from STEMI and use of preventive strategies such as preprocedural intubation in high risk patients when PPCI is the preferred strategy may be reasonable to reduce provider risk of COVID-19 infection.

The First 4 Years of Postmarketing Safety Surveillance Related to the MitraClip Device: A United States Food and Drug Administration MAUDE Experience

OBJECTIVE

The MitraClip (Abbott) is a commercially available device to perform percutaneous transcatheter mitral valve repair (TMVR) for patients with symptomatic mitral regurgitation (MR). Recent data support its role in appropriately selected patients with functional MR, and its use is poised to increase. However, limited safety data in "real-world" practice are available after market introduction.

METHODS

We queried all available adverse event reports from the publicly available Manufacturer and User Facility Device Experience (MAUDE) database including "injuries" and "deaths" from October 2013 (date of Food and Drug Administration [FDA] premarket approval) to September 2017 using the following search limits: brand name ("MitraClip") and product code ("NKM," a unique FDA designation linked to MitraClip).

RESULTS

During the first 4 years after FDA approval, MAUDE received 200 death reports and 1666 injury reports containing 2974 unique adverse events. Of all death reports, 21% described deaths occurring >1 year post MitraClip and 30% included limited details. The top three known causes of death included complications requiring rescue high-risk surgery, clip detachment or unsuccessful clip placement, and damage to the valvular apparatus. Similar non-fatal events were reported. Additional procedures or surgical intervention were required in 227 injury events (8%).

CONCLUSIONS

While injuries reported to the FDA have steadily increased with more widespread use of TMVR, device- or procedure-related death reports have accrued more slowly, corroborating a potential institutional or operator learning curve with this device. However, in light of incomplete and poor data quality, higher-fidelity systems of postmarketing safety surveillance are needed in the evaluation of emerging devices.

P265 Infective endocarditis:think global, act local:changing trends in infective endocarditis-integrating antibiotic stewardship program: data from developing world

Despite improvements in diagnostic and therapeutic strategies, both the incidence, severity & mortality of Infective Endocarditis (IE) seem to be unchanged.The pattern of  the disease in terms of host, agent & environment changing rapidly.The successful integration of antibiotic stewardship program along with the appropriate use of antibiotic agents has made a huge difference in the treatment strategy & cost reduction in patient care for IE. Materials & Methods: A single centre, retrospective & prospective study done between 2009 to 2018. The diagnosis of infective endocarditis was done as per the modified Duke’s Criteria. 355 patients were analysed and baseline demographic data with echocardiographic, microbiologic,complications, treatment & outcomes noted. All blood cultures processing was done with BACTEC and BacTAlert using standard precautions.Antibiotic stewardship program was initiated since February 2016 as per international protocol. Results: The mean age of the study population was 46.7+-3 years. Predominanlty streptococcus species ( 21.4%) was isolated in the culture.A definite rise in atypical (17.9%) organism was noted in 2018 over the period of study as compared to 2009 : Presence of Burkholderia, Candida, Atypical Mycobacterium spp increased. Despite the advances in diagnostic modalities,there has been no change in mortality associated with IE (10.3%) over the period of 2009-2018. There is a predominantly native Mitral Valve involvement (53.7%) & a definite rise in Prosthetic Valve endocarditis (19.6%) noted in the last 5 years. Conclusion:This study is the largest study & data on Infective Endocarditis so far from a single centre in a developing world with a study population of 355 patients. Risk factors for IE have changed over time.Newer paradigms in treating IE and integration of antibiotic stewardship program has successfully brought down the cost and increased care in this part of the developing world.

Changing trends : Organism Profile in IE Year Strept(%) Staph(%) Entero(%) Atypical(%) 2009 26.2 2.4 7.1 7.1 2011 24 8 12 16 2013 20 10 10 17.5 2015 27.3 12.7 3.6 20 2016 13.6 31.8 4.5 18.2 2017 27.6 13.8 10.3 34.5 2018 21.4 17.9 10.7 17.9

Abstract P265 Figure. Changing Epidemiological trends in IE

The safety and efficacy of neuromodulation using percutaneous electrical nerve stimulation for the management of trigeminal-mediated headshaking in 168 horses

Background

Early results from the use of neuromodulation by percutaneous electrical nerve stimulation for the management of trigeminal‐mediated headshaking in horses were promising but lacked sufficient case numbers and long‐term follow‐up. The neuromodulatory procedure has since been established as EquiPENS™.

Objectives

The aim of this study was to report long‐term results from a larger number of cases and to investigate for predictors of outcome.

Study design

Prospective case series using international, multi‐centre data.

Methods

Eligible cases were horses with a veterinary diagnosis of trigeminal‐mediated headshaking, which received EquiPENS™ neuromodulation at trained centres between August 2013 and November 2017. The standard protocol was an initial three‐procedure course, with additional procedures should a horse go into remission but then relapse. Data collected included signalment, history, diagnostic tests performed, details of any complications, whether horses had gone into remission and the length of remission.

Results

Results were obtained from 168 horses, with 530 procedures. The complication rate was 8.8% of procedures. In all but one case, complications were mild and transient, without self‐trauma. Remission of headshaking following the initial course occurred in 53% (72/136) of horses. Median length of time recorded in remission was 9.5 weeks (range 2 days to 156 weeks ongoing). Where signs recurred, most horses went back into remission following additional procedures, usually for longer than from the previous procedure. No predictors for outcome were determined.

Main limitations

No placebo or control group, owner‐assessed results.

Conclusions

EquiPENS™ neuromodulation can be an effective and safe treatment for the management of trigeminal‐mediated headshaking in some horses. An increased understanding of neuromodulation could help optimise the technique. Advances in treatment for trigeminal‐mediated headshaking will remain limited until there is a greater understanding of the aetiopathogenesis of the condition.

Pathologists’ Views on Consent for Autopsy

Consent to autopsy is usually obtained by a doctor other than the one who will perform the procedure. There is an argument that, for proper informed consent, a pathologist should participate. We ascertained the views of consultant pathologists in south-east England.

53 (87%) of 61 consultants responded, of whom 50 currently do autopsies. Only 2 at present participate directly in obtaining consent, and 10 of the remaining 48 expressed willingness to do so. The general view was that consent is best obtained by a senior clinician from the team that has looked after the patient.

Pathologists see their primary role as to provide guidance to clinicians. Few see it as their function to obtain consent for autopsy.

Trials based on specific fracture configuration and surgical procedures likely to be more relevant for decision making in the management of fractures of the proximal humerus: Findings of a meta-analysis

Objectives

The objective of this study was to perform a meta-analysis of all randomised controlled trials (RCTs) comparing surgical and non-surgical management of fractures of the proximal humerus, and to determine whether further analyses based on complexity of fracture, or the type of surgical intervention, produced disparate findings on patient outcomes.

Methods

A systematic review of the literature was performed identifying all RCTs that compared surgical and non-surgical management of fractures of the proximal humerus. Meta-analysis of clinical outcomes was performed where possible. Subgroup analysis based on the type of fracture, and a sensitivity analysis based on the type of surgical intervention, were also performed.

Results

Seven studies including 528 patients were included. The overall meta-analysis found that there was no difference in clinical outcomes. However, subgroup and sensitivity analyses found improved patient outcomes for more complex fractures managed surgically. Four-part fractures that underwent surgery had improved long-term health utility scores (mean difference, MD 95% CI 0.04 to 0.28; p = 0.007). They were also less likely to result in osteoarthritis, osteonecrosis and non/malunion (OR 7.38, 95% CI 1.97 to 27.60; p = 0.003). Another significant subgroup finding was that secondary surgery was more common for patients that underwent internal fixation compared with conservative management within the studies with predominantly three-part fractures (OR 0.15, 95% CI 0.04 to 0.63; p = 0.009).

Conclusion

This meta-analysis has demonstrated that differences in the type of fracture and surgical treatment result in outcomes that are distinct from those generated from analysis of all types of fracture and surgical treatments grouped together. This has important implications for clinical decision making and should highlight the need for future trials to adopt more specific inclusion criteria.

Cite this article: S. Sabharwal, N. K. Patel, D. Griffiths, T. Athanasiou, C. M. Gupte, P. Reilly. Trials based on specific fracture configuration and surgical procedures likely to be more relevant for decision making in the management of fractures of the proximal humerus: Findings of a meta-analysisBone Joint Res 2016;5:470–480. DOI: 10.1302/2046-3758.510.2000638.

The cost of adverse events from knee surgery in the United Kingdom: an in-depth review of the National Health Service Litigation Authority database

BACKGROUND

There has been a significant rise in the number and value of claims against the National Health Service (NHS), with limited studies on litigation in orthopaedic surgery and none in knee surgery alone. We aimed to examine claims against the NHS involving all aspects of knee surgery with respect to costs and trends.

CLINICAL RELEVANCE

To raise awareness of the reasons for litigation in knee surgery, thus potentially improve patient care and reduce future claims.

METHODS

We analysed the NHS litigation authority (NHSLA) database for all orthopaedic surgery claims reported to the NHSLA between 2005 and 2010, with calculation of litigation success rates and odds ratios for those relating to knee surgery.

RESULTS

There were 515 cases identified from the 4609 orthopaedic cases in the NHSLA database (11.2%): 298 (58%) involving total knee replacements (TKRs), 11 (2%) involving unicondylar knee replacements, and 90 cases (30%) remaining open. The total pay out for closed cases was £10.45 million and amputation following TKR resulted in the highest single pay out. Litigation success rates for claimants were highest for retained drains (100%), incorrect prosthesis/prosthesis size (78%), renal failure (75%), poor outcome requiring further surgery (74%) and malalignment (71%). There were also 60 cases of delayed diagnosis which resulted in pay outs totalling £2.90 million. Based on these data, projected future pay out costs for the open TKR cases were estimated to be £2.71 million.

CONCLUSION

Litigation success rates for TKR were highest following technical errors such as malalignment compared to events less under the surgeon's control, such as infection. The number of claims involving incorrect prosthesis/size continues to be of concern. Despite the increased availability of imaging modalities, missed diagnosis also resulted in substantial pay outs.

A single-center evaluation of the risk for colonization or bacteremia with piperacillin-tazobactam- and cefepime-resistant bacteria in patients with acute leukemia receiving fluoroquinolone prophylaxis

Fluoroquinolone prophylaxis is indicated to prevent neutropenic fever in patients with acute leukemia. However, fluoroquinolone use has been associated with development of multi-drug-resistant Pseudomonas aeruginosa and extended spectrum β-lactamase producing gram-negative bacilli. Due to a presumed risk of multi-drug resistance associated with fluoroquinolone prophylaxis, patients admitted to our hospital with neutropenic fever receive empiric carbapenem therapy until cultures are negative for 72 h or identification of an organism. Our study seeks to identify the incidence of multi-drug-resistant organism colonization and bacteremia among patients who receive fluoroquinolone prophylaxis and to evaluate duration of empiric carbapenem therapy. A retrospective review of adult patients with acute leukemia receiving a fluoroquinolone as outpatient infection prophylaxis, admitted to our tertiary cancer center for treatment of neutropenic fever was completed. Surveillance and blood cultures were reviewed for antibiotic resistance. Duration of empiric carbapenem therapy was reviewed. One hundred patients and 177 admissions for neutropenic fever were included. Six patients harbored a piperacillin-tazobactam-resistant organism found during routine surveillance. Among these patients, two bacteremias were identified, one of which was a piperacillin-tazobactam-resistant organism. Five bacteremias were identified among 83 patients with negative surveillance cultures. Among the bloodstream infections, five organisms isolated were fluoroquinolone resistant. No cefepime-resistant organism was isolated on surveillance or bloodstream cultures. Adherence to the institution guideline of narrowing antibiotics after 72 h of negative cultures occurred in only 13% of neutropenic fever cases. The average duration of carbapenem therapy in 177 neutropenic fever episodes was 4.4 days. Our findings show that among our patient population, there is a low risk of bacteremia with a piperacillin-tazobactam-resistant or cefepime-resistant organism. However, prompt de-escalation of carbapenem therapy needs to be reiterated within hospital practice.

An intensive medical education elective for senior medical students

Peer teaching by medical students is increasingly consid- ered an effective and efficient instructional modality with value for both teachers and learners. In 2012, twelve senior medical students participated in an inaugural, four-week Medical Education Elective at The Alpert Medical School of Brown University. The first week emphasized education theory and skills. During the remaining three weeks, participants served as a core group of instructors in a Clinical Skills Clerkship (CSC), a three-week required course transitioning rising third-year students to clinical clerkships. Senior near-peer instructors (NPIs) gained substantive experience in developing curriculum, facilitating small group sessions, teaching clinical skills, mentoring, providing feedback, and grading an Objective Structured Clinical Examination (OSCE). Based on direct observation by faculty and written anonymous evaluations by learners (n=98), NPIs demonstrated a high degree of teaching competence. This innovative, by-invitation-only, annual elective is the most substantive medical education experience for medical students described in the literature.

A new clinical skills clerkship for medical students

BACKGROUND AND OBJECTIVES

The transition to clinical clerkships can be challenging for medical students. In the context of a formal clinical curriculum redesign, a curriculum team led by family physicians systematically planned and implemented a 3-week course to prepare new third-year students for specialty-specific clerkships.

METHODS

Informed by a formal needs assessment, we developed a classroom-based Clinical Skills Clerkship (CSC) with varied instructional approaches. The three major curriculum components are (1) specialty-specific, longitudinal clinical care of a three-generation virtual family that is taught in lectures and small groups and assessed with an objective structured clinical examination (OSCE), (2) clinical skills including procedure stations and interprofessional education experiences, and (3) a series of professional development activities. The CSC has 90 hours of curriculum taught by more than 120 faculty members from a wide variety of specialties and disciplines. A cohort of senior medical students teach in the course as part of a medical education elective.

RESULTS

The CSC was first delivered to 98 students in 2012 who performed well on the course's OSCE. Quantitative and qualitative evaluations of both the curriculum components and the senior medical student teachers were positive. Performance on comparable CSC and Internal Medicine Clerkship OSCE stations and a series of student focus groups demonstrate longer-term impact.

CONCLUSIONS

A successful curriculum redesign requires considerable planning and coordination. We designed and implemented a comprehensive CSC that was both well received and effective. Peer teaching programs can provide medical education leadership experiences with benefits for learners, teachers, and medical educators.

Hip resurfacing arthroplasty at a non-specialist centre

INTRODUCTION

Few studies have reported the outcome of hip resurfacing arthroplasty (HRA) with respect to implant characteristics from non-specialist centres. We report the survival, clinical and radiological outcomes of a single surgeon series of HRA with an average follow-up duration of five years.

METHODS

All consecutive HRAs performed by a single surgeon between 2003 and 2011 at a district general hospital were retrospectively examined clinically and radiologically.

RESULTS

A total of 85 patients underwent 109 HRAs (58 male [53.2%] and 51 female patients [46.8%]) with a mean follow-up period of 62 months (range: 12-102 months). The median age was 57 years (range: 25-75 years). The mean acetabular and femoral head component sizes were 54 mm (range: 48-64 mm) and 48 mm (range: 42-58 mm) respectively with a mean acetabular inclination angle of 42.9° (range: 20-75°). The survival rate was 95% with five revisions due to aseptic loosening (n=3) and fracture (n=2): these were predominantly for female patients (n=4), with significantly smaller mean acetabular (51 mm, p=0.04) and femoral (44 mm, p=0.02) implant sizes. Furthermore, they had a higher mean acetabular inclination angle of 48.1° (p=0.74). The mean Oxford hip score was 43.8 (range: 25-48) and the mean University of California Los Angeles (UCLA) activity score was 6.8 (range: 3-10). Radiological findings included heterotopic ossification in 13 (11.9%), radiolucent lines in 6 (5.5%), femoral neck thinning in 2 (1.8%) and femoral neck notching in 5 patients (4.6%).

CONCLUSIONS

We have shown that HRA at a non-specialist centre has short to medium-term outcomes comparable with those at specialist centres. HRA therefore remains a viable option although vigilance is required in case selection and follow-up according to national guidance.

The ruptured Achilles tendon: a current overview from biology of rupture to treatment

The Achilles tendon (AT) is the most frequently ruptured tendon in the human body yet the aetiology remains poorly understood. Despite the extensively published literature, controversy still surrounds the optimum treatment of complete rupture. Both non-operative management and percutaneous repair are attractive alternatives to open surgery, which carries the highest complication and cost profile. However, the lack of a universally accepted scoring system has limited any evaluation of treatment options. A typical UK district general hospital treats approximately 3 cases of AT rupture a month. It is therefore important for orthopaedic surgeons to correctly diagnose and treat these injuries with respect to the best current evidence-based practice. In this review article, we discuss the relevant pathophysiology and diagnosis of the ruptured AT and summarize the current evidence for treatment.

Atraumatic posterior dislocation of the native hip: an unusual presentation of septic arthritis

We present a case of chronic posterior hip dislocation after severe joint destruction following septic arthritis. In the absence of trauma, infection must be considered in the differential diagnosis of a dislocated joint particularly in patients with risk factors such as intravenous drug abuse and immune compromise. Excision arthroplasty of the hip was performed with good pain relief and functional outcomes. This is an excellent temporary or permanent solution in managing such complex cases although alternative management options are discussed.

Prediction of skin sensitization potential using D-optimal design and GA-kNN classification methods

Modelling of skin sensitization data of 255 diverse compounds and 450 calculated descriptors was performed to develop global predictive classification models that are applicable to whole chemical space. With this aim, we employed two automated procedures, (a) D-optimal design to select optimal members of the training and test sets and (b) k-Nearest Neighbour classification (kNN) method along with Genetic Algorithms (GA-kNN Classification) to select significant and independent descriptors in order to build the models. This methodology helped us to derive multiple models, M1-M5, that are stable and robust. The best among them, model M1 (CCR(train) = 84.3%, CCR(test) = 87.2% and CCR(ext) = 80.4%), is based on six neighbours and nine descriptors and further suggests that: (a) it is stable and robust and performs better than the reported models in literature, and (b) the combination of D-optimal design and GA-kNN classification approach is a very promising approach. Consensus prediction based on the models M1-M5 improved the CCR of training, test and external validation datasets by 3.8%, 4.45% and 3.85%, respectively, over M1. From the analysis of the physical meaning of the selected descriptors, it is inferred that the skin sensitization potential of small organic compounds can be accurately predicted using calculated descriptors that code for the following fundamental properties: (i) lipophilicity, (ii) atomic polarizability, (iii) shape, (iii) electrostatic interactions, and (iv) chemical reactivity.

To replace or not to replace? - Partial coning and a sixth nerve palsy secondary due to displacement of a tunnelled intrathecal catheter for pain control

We report the displacement of a tunnelled intrathecal catheter causing significant cerebrospinal fluid (CSF) leak, resulting in partial coning and a sixth nerve palsy. The patient had advanced malignant mesothelioma and all other methods of pain control had been unsuccessful. As far as we are aware, there are no published reports of early replacement of an intrathecal catheter in patients with neurological sequelae. Surgical re-siting of the intrathecal catheter produced good pain relief for many months. Doctors involved in the use of indwelling intrathecal catheters for pain control must be aware of the risk of significant neurological sequelae but should not dismiss re-establishment of intrathecal therapy in the presence of significant neurological complications.

GDNF delivery for Parkinson's disease

The mainstays of Parkinson's disease (PD) treatment remain symptomatic, including initial dopamine replacement and subsequent deep brain stimulation, however, neither of these approaches is neuroprotective. Neurotrophic factors - proteins that activate cell signalling pathways regulating neuronal survival, differentiation, growth and regeneration - represent an alternative for treating dopaminergic neurons in PD but are difficult to administer clinically because they do not pass through the blood-brain barrier. Glial cell line-derived neurotrophic factor (GDNF) has potent neurotrophic effects particularly but not exclusively on dopaminergic neurons; in animal models of PD, it has consistently demonstrated both neuroprotective and neuroregenerative effects when provided continuously, either by means of a viral vector or through continuous infusion either into the cerebral ventricles (ICV) or directly into the denervated putamen. This led to a human PD study in which GDNF was administered by monthly bolus intracerebroventricular injections, however, no clinical benefit resulted, probably because of the limited penetration to the target brain areas, and instead significant side effects occurred. In an open-label study of continuous intraputamenal GDNF infusion in five patients (one unilaterally and four bilaterally), we reported excellent tolerance, few side effects and clinical benefit evident within three months of the commencement of treatment. The clinical improvement was sustained and progressive, and by 24-months patients demonstrated a 57 and 63% improvement in their off-medication motor and activities of daily living UPDRS subscores, respectively, with clear benefit in dyskinesias. The benefit was associated with a significant increase in putamenal 18F-dopa uptake on positron emission tomography (PET), and in one patient coming to autopsy after 43 months of unilateral infusion there was evident increased tyrosine hydroxylase immunopositive nerve fibres in the infused putamen. A second open trial in 10 patients using unilateral intraputamenal GDNF infusions has also demonstrated a greater than 30% bilateral benefit in both on- and off-medication scores at 24 weeks. Based on our 6-month results, a randomized controlled clinical trial was conducted to confirm the open-label results, however, GDNF infusion over 6-months did not confer the predetermined level of clinical benefit to patients with PD despite increased 18F-dopa uptake surrounding the catheter tip. It is possible that technical differences between this trial and the positive open label studies contributed to this negative outcome.

Radiofrequency ablation (coblation): a promising new technique for laryngeal papillomata

This paper describes a new application for radiofrequency ablation in head and neck surgery. Two patients with extensive laryngeal papillomata were successfully treated using this technology. The technique is described in detail, highlighting the main benefits of this approach as compared with existing techniques. These advantages include limited damage to underlying tissues and a bloodless field.

Some patients with multiple sclerosis have neurovascular compression causing their trigeminal neuralgia and can be treated effectively with MVD: report of five cases

The role of trigeminal ganglion percutaneous injection and radio-frequency lesioning procedures for the treatment of trigeminal neuralgia (TGN) in multiple sclerosis (MS) is well established. There is general acceptance that microvascular decompression (MVD) cannot be an appropriate treatment due to the view that the underlying aetiology is a demyelinating plaque affecting the root entry zone of the trigeminal pathway. Recently, MR-imaging has been used in the preoperative investigation of this group of patients demonstrating that neurovascular compression can occasionally be the responsible mechanism and that MVD can be the treatment of choice. We present five cases with MS and TGN. All the patients had failed to respond to medical treatment or percutaneous procedures. Magnetic resonance imaging demonstrated evidence of neurovascular compression in four cases. All the patients underwent MVD. Postoperatively four of the five patients made an uncomplicated recovery, were pain-free and fully satisfied with the result (mean follow-up 38.75 months; range 8-59 months). One patient developed recurrent pain 1 week following surgery and went on to have a total sensory rhizotomy. TGN in MS can be caused by neurovascular compression, which may be identified on MR-imaging. MVD has offered satisfactory short-term outcome for at least 2 years and does not inflict sensory loss. Longer follow-up will determine whether the outcome in MS patients will be as successful as in the TGN patients who do not suffer from MS.

Zero-order release of aspirin, theophylline and atenolol in water from novel methylcellulose glutarate matrix tablets

A novel hydrocolloidal polymer, methylcellulose glutarate (MC-GA), was prepared by esterifying methylcellulose with glutaric anhydride. The formation of ester was confirmed by FTIR and NMR spectroscopy, DSC and elemental analysis. The physicochemical properties such as, rate of swelling in water, viscosity and hygroscopicity of MC-GA were determined and compared with those of methycellulose A (MC). Aspirin, theophylline and atenolol tablets were compacted on a Carver press using the wet granulation method. Each tablet contained: 200 mg active, 80 mg anhydrous lactose, 8 mg povidone, 4 mg magnesium stearate, 4 mg talc, 50mg MC or MC-GA (drug-to-polymer ratio, 4:1). Contrary to the first-order release profile of all the drugs from the MC matrix tablets, a zero-order release was obtained from the MC-GA matrix tablets in water.

Open labeled, randomized, switch-over study of two fixed doses (10/15mg) of aripiprazole : to evaluate its safety and efficacy in the treatment of Indian patients of schizophrenia

Aripiprazole is a new anti psychotic with a unique receptor binding profile that combines partial agonistic activity at D2 receptor and 5-HT 1A receptor and potent antagonism at 5-HT 2A receptor. This receptor profile makes it possible for it to act as a dopamine system stabilizer. Based on various short term and long term studies, aripiprazole has been found to be effective in schizophrenia and has no significant adverse effect on QTc prolongation, prolactin, serum lipids, and has a low potential for weight gain. Present study aims to evaluate the efficacy and tolerability of aripiprazole (10-15mg/day) in the treatment of Indian patients of schizophrenia and to see its effect on QTc interval, prolactin levels, serum lipids, plasma sugar and weight gain in these patients. Outpatients with an ongoing/newly diagnosed ICD-10 Schizophrenia (n=136) were randomly assigned to 10 or 15 mg dose of Aripiprazole for a period of six weeks. Clinical response was evaluated by the Positive And Negative Symptoms Scale (PANSS), Clinical Global Impression (CGI) scale and safety was evaluated by observing spontaneously reported adverse events and changes in various laboratory parameters. Switching schizophrenic patients to aripiprazole (10/15 mg) from both conventional and atypical anti-psychotics was safe and well tolerated. Six weeks after switching to aripiprazole, patients showed improvements in PANSS scores (P< 0.001), EPS, prolactin levels and weight over the baseline levels. No difference was seen in the 10 or 15mg dose groups. One hospitalization was reported (due to hepatitis E). Common side effects reported were insomnia, somnolence, nausea, vomiting and diarrhea. Aripiprazole is a safe and effective anti psychotic in Indian patients - both in newly diagnosed, as well as, in patients not responding to or intolerant to other available typical and atypical antipsychotics.

MRI directed bilateral stimulation of the subthalamic nucleus in patients with Parkinson's disease

OBJECTIVE

Bilateral chronic high frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) has emerged as an appropriate therapy for patients with advanced Parkinson's disease refractory to medical therapy. Advances in neuroimaging and neurophysiology have led to the development of varied targeting methods for the delivery of this treatment. Intraoperative neurophysiological and clinical monitoring is regarded by many to be mandatory for accurate STN localisation. We have examined efficacy of bilateral STN stimulation using a predominantly magnetic resonance imaging (MRI)-directed technique.

METHODS

DBS leads were stereotactically implanted into the STN using an MRI directed method, with intraoperative macrostimulation used purely for adjustment. The effects of DBS were evaluated in 16 patients followed up to 12 months, and compared with baseline assessments. Assessments were performed in both off and on medication states, and were based on the Unified Parkinson's Disease Rating Scale (UPDRS) and timed motor tests. Functional status outcomes were examined using the PDQ-39 quality of life questionnaire. A battery of psychometric tests was used to assess cognition.

RESULTS

After 12 months, stimulation in the off medication state resulted in significant improvements in Activities of Daily Living and Motor scores (UPDRS parts II and III) by 62% and 61% respectively. Timed motor tests were significantly improved in the off medication state. Motor scores (UPDRS part III) were significantly improved by 40% in the on medication state. Dyskinesias and off duration were significantly reduced and the mean dose of L-dopa equivalents was reduced by half. Psychometric test scores were mostly unchanged or improved. Adverse events were few.

CONCLUSIONS

An MRI directed targeting method for implantation of DBS leads into the STN can be used safely and effectively, and results are comparable with studies using intraoperative microelectrode neurophysiological targeting. In addition, our method was associated with an efficient use of operating time, and without the necessary costs of microelectrode recording.

How accurate is magnetic resonance angiography in predicting neurovascular compression in patients with trigeminal neuralgia? A prospective, single-blinded comparative study

Ninety-two patients with trigeminal neuralgia (TGN) were investigated prior to posterior fossa surgery with magnetic resonance imaging (MRI) and contrast-enhanced magnetic resonance angiography (MRA). The preoperative investigation was matched to one consultant neuroradiologist (co-author) who was blinded to the side of symptomotology. The imaging results were compared with the operative findings in all patients. In 76 patients MRA showed present neurovascular compression in accordance with surgical findings. Eight cases had no compression either on MRA or intraoperatively. Eight predictions of no compression were false and there was no false positive. Based on surgical findings, the sensitivity of MRA was 90.5% and the specificity 100%. In 19 cases MRA predicted bilateral compression of the trigeminal nerves. Only two cases had clinically bilateral TGN. We conclude that MRA with gadolinium enhancement is an extremely sensitive and specific method for demonstrating compression in TGN. As a result posterior fossa surgery can be recommended with confidence, and microvascular decompression remains the treatment of choice for TGN at the authors' centre.

Pathologists' views on consent for autopsy

Consent to autopsy is usually obtained by a doctor other than the one who will perform the procedure. There is an argument that, for proper informed consent, a pathologist should participate. We ascertained the views of consultant pathologists in south-east England. 53 (87%) of 61 consultants responded, of whom 50 currently do autopsies. Only 2 at present participate directly in obtaining consent, and 10 of the remaining 48 expressed willingness to do so. The general view was that consent is best obtained by a senior clinician from the team that has looked after the patient. Pathologists see their primary role as to provide guidance to clinicians. Few see it as their function to obtain consent for autopsy.

Granulomatous ulcerative colitis: a re-appraisal of the mucosal granuloma in the distinction of Crohn's disease from ulcerative colitis

AIMS

To determine whether the presence and location of giant cells or granulomas in relation to crypts distinguishes between ulcerative colitis and Crohn's disease.

METHODS AND RESULTS

Twenty-nine large bowel mucosal biopsy specimens showing giant cells and/or granulomas in a background more typical of ulcerative colitis than Crohn's disease were collected between 1986 and 1996. Each was subject to detailed independent analysis by three histopathologists. Follow-up of the cases was by examination of all previous and subsequent gastrointestinal surgical or biopsy material and by scrutiny of the clinical notes by a gastroenterologist. On the basis of the accumulated histological data 10 of these 29 cases were accorded the diagnosis of ulcerative colitis. In nine of these 10 cases the clinical diagnosis, where known, was in keeping with this and all nine contained only crypt-associated giant cells and/or granulomas. The tenth case contained a solitary free-standing granuloma and clinically the patient had perianal disease, suggesting that the true diagnosis was Crohn's disease.

CONCLUSIONS

Isolated giant cells and well-defined epithelioid granulomas distant from crypts do not, as a rule, occur in ulcerative colitis, and hence their presence in a colonoscopic biopsy showing features of chronic inflammatory bowel disease is a strong pointer towards the diagnosis of Crohn's disease. Crypt-associated giant cells and granulomas can occur in ulcerative colitis and in themselves are unreliable features for the discrimination between Crohn's disease and ulcerative colitis.

Conformational nature of the Borrelia burgdorferi decorin binding protein A epitopes that elicit protective antibodies

Decorin binding protein A (DbpA) has been shown by several laboratories to be a protective antigen for the prevention of experimental Borrelia burgdorferi infection in the mouse model of Lyme borreliosis. However, different recombinant forms of the antigen having either lipidated amino termini, approximating the natural secretion and posttranslational processing, or nonprocessed cytosolic forms have elicited disparate levels of protection in the mouse model. We have now used the unique functional properties of this molecule to investigate the structural requirements needed to elicit a protective immune response. Genetic and physicochemical alterations to DbpA showed that the ability to bind to the ligand decorin is indicative of a potent immunogen but is not conclusive. By mutating the two carboxy-terminal nonconserved cysteines of DbpA from B. burgdorferi strain N40, we have determined that the stability afforded by the putative disulfide bond is essential for the generation of protective antibodies. This mutated protein was more sensitive to thermal denaturation and proteolysis, suggesting that it is in a less ordered state. Immunization with DbpA that was thermally denatured and functionally inactivated stimulated an immune response that was not protective and lacked bactericidal antibodies. Antibodies against conformationally altered forms of DbpA also failed to kill heterologous B. garinii and B. afzelii strains. Additionally, nonsecreted recombinant forms of DbpA(N40) were found to be inferior to secreted lipoprotein DbpA(N40) in terms of functional activity and antigenic potency. These data suggest that elicitation of a bactericidal and protective immune response to DbpA requires a properly folded conformation for the production of functional antibodies.

Clostridium novyi infection: a fatal association with injecting drug users

Injecting drug users frequently use accident and emergency (A&E) departments to access emergency care for local and systemic infections. Clostridium novyi type A is a bacterium that has recently been associated with a number of fatalities among drug injecting addicts. The clinical course is described of a patient who attended an A&E department with septicaemia who was found at postmortem examination to have been infected with Clostridium novyi type A. Doctors working in A&E departments should be aware of the existence of this infection and be vigilant when treating injecting drug users with localised infection.

Evidence for vaccine synergy between Borrelia burgdorferi decorin binding protein A and outer surface protein A in the mouse model of lyme borreliosis

Mice immunized with either the predominantly vector-stage lipoprotein outer surface protein A (OspA) or the in vivo-expressed lipoprotein decorin binding protein A (DbpA) are protected against Borrelia burgdorferi challenge. DbpA-OspA combinations protected against 100-fold-higher challenge doses than did either single-antigen vaccine and conferred significant protection against heterologous B. burgdorferi, B. garinii, and B. afzelii isolates, suggesting that there is synergy between these two immunogens.

Survival of premenopausal breast carcinoma patients in relation to menstrual cycle timing of surgery and estrogen receptor/progesterone receptor status of the primary tumor

BACKGROUND

Premenopausal breast carcinoma patients who undergo tumor excision during the follicular phase of their menstrual cycle may have a significantly worse prognosis than those whose tumors are excised in other phases of the menstrual cycle.

METHODS

Outcome was determined in a series of 112 premenopausal women with operable breast carcinoma in relation to the timing of surgery within the menstrual cycle and the estrogen receptor (ER) and progesterone receptor (PR) status of their primary tumors as determined by immunohistochemistry.

RESULTS

Those patients with ER positive tumors who underwent surgery in the early and luteal phase of the cycle had a significantly better survival than women with ER negative tumors (chi-square test = 15.56; P < 0.001). This also was true for PR status (chi-square test = 18.21; P < 0.001). After follicular phase surgery, tumor receptor status had no effect on overall survival. Patients with the best prognosis had ER/PR positive tumors excised on Days 0-2 and 13-32 but even those women with ER or PR negative tumors removed during the luteal phase of their menstrual cycle fared better than patients whose tumors were removed during the follicular phase.

CONCLUSIONS

There was a better survival rate for patients with both ER/PR positive and negative tumors treated during the luteal phase of the menstrual cycle. This could be the result of progesterone acting on the surrounding peritumoral normal tissue, thereby exerting a straitjacket effect and improving cohesion of the primary carcinoma. Unopposed estrogen in the follicular phase of the cycle may enable more tumor emboli to escape and successfully establish micrometastases.

In vitro release and diffusion studies of promethazine hydrochloride from polymeric dermatological bases using cellulose membrane and hairless mouse skin

The study was designed to investigate the feasibility of developing a transdermal drug dosage form of promethazine hydrochloride (PMH). The in vitro release and diffusion characteristics of PMH from various dermatological polymeric bases were studied using cellulose membrane and hairless mouse skin as the diffusion barriers. These included polyethylene glycol (PEG), hydroxypropyl methylcellulose (HPMC), cross-linked microcrystalline cellulose, and carboxyl methyl cellulose sodium (Avicel CL-611), and a modified hydrophilic ointment USP. In addition, the effects of several additive ingredients known to enhance the drug release from topical formulations were evaluated. The general rank order for the drug release from these formulations using cellulose membrane was observed to be PEG > HMPC > Avicel CL-611 > hydrophilic ointment base. The inclusion of the additives had little or no effect on the drug diffusion from these bases, except for the hydrophilic ointment formulation containing 15% ethanol, which provided a significant increase in the drug release. However, when these formulations were studied for drug diffusion through the hairless mouse skin, the Avicel CL-611 base containing 15% ethanol exhibited the optimum drug release. The data also revealed that this formulation gave the highest steady-state flux, diffusion, and permeability coefficient values and correlated well with the amount of drug release.