Patellofemoral joint arthroplasty: patient selection,surgical technique and outcomes

Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome.     

P21 Design and operation of a human breath freshness panel

Objective  Practical treatment of halitosis requires tongue cleaning since volatile sulphur compounds (VSC) seems mainly to be from the tongue coating. From this point of view, mechanical tools such as tongue brushes or scrapers have been developed. However, approaches by chemical tongue cleaning have not been reported. Thus we developed tablets containing protease from kiwifruits, which could resolve tongue coating, and assessed the effects of the protease tablet to control tongue coating.
Methods  Crossover studies and double blind experiments were designed using volunteers with informed consent. The trial was done twice per volunteer, that is, they had a tablet with or without the addition of protease from kiwifruits (test and placebo) with intervening washout periods of at least 2 weeks. The degree of change in tongue coating was evaluated visually using a tongue coating score which consisted of an area component (0–3) and a thickness component (0–3). An image analyzer was also used to measure the changing in actual area of coating.
Results  The average value of the tongue coating scores after taking a test tablet (11.4 ± 5.2) was significantly smaller ( P  < 0.01) than before taking the tablet (18.8 ± 7.0). Image analyzer measurements also showed significant reduction ( P  < 0.01) of tongue coating by taking test tablet. On the other hand, a placebo tablet showed no significant effects in both analyses.
Conclusions  This study indicated that taking protease tablets could reduce tongue coating. We are planning further clinical trials that can show reduced VSC concentrations in mouth air with decreasing tongue coating.     

Using mobile technology to overcome language barriers in medicine

Australia has a large migrant population with variable fluency in English. Interpreting services help ensure that healthcare services are delivered appropriately to these populations. However, the use of professional interpreters in hospitals is expensive. There are also issues with service availability and convenience. Mobile devices containing software with translating abilities have promising potential to improve communication between patients and hospital staff as an adjunct to professional interpreters. It is highly convenient and inexpensive. There are concerns about the accuracy of the interpretation done with such software and more research needs to be carried out to support or allay these concerns. For now, clinically important and medicolegal related interpretation should be undertaken by professional interpreters whereas less crucial tasks may be performed with the help of interpreting software on mobile devices.     

Systematic review of enhanced recovery after gastro-oesophageal cancer surgery

Introduction

Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.

Methods

A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.

Results

From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.

Conclusions

The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay.     

The effect of gentamicin on antidiuretic hormone-stimulated osmotic water flow in the toad urinary bladder

Early gentamicin nephrotoxicity is characterized by a variety of renal transport abnormalities, including polyuria secondary to nephrogenic diabetes insipidus. To investigate whether gentamicin directly interferes with cellular mechanisms responsible for ADH responsivity as a possible contributing factor in this tubular transport alteration, the effect of gentamicin on ADH-stimulated water flow was examined in vitro in the toad urinary bladder. Gentamicin decreased ADH-stimulated osmotic water flow in a dose-dependent manner, with a threshold effect at approximately 0.5 mM. This inhibitory effect occurred only in response to submaximal concentrations of ADH, was reversible, and was preventable with Mg++. Additionally, gentamicin reduced theophylline-stimulated osmotic water flow but had no effect on cyclic AMP-induced water flow. These effects are consistent with a direct gentamicin-related decrease in ADH-responsive adenylate cyclase activity and suggest a mechanism that may contribute to the nephrogenic diabetes insipidus characteristic of early gentamicin nephrotoxicity and the nonoliguric acute renal failure that is a late toxic event occurring with the use of this antibiotic.     

Neutrophil accumulation in the lung in alpha 1-antitrypsin deficiency. Spontaneous release of leukotriene B4 by alveolar macrophages.

The emphysema of alpha 1-antitrypsin (alpha 1AT) deficiency is conceptualized to result from insufficient alpha 1AT allowing neutrophil elastase to destroy lung parenchyma. In addition to the deficiency of alpha 1AT in these individuals resulting from mutations in the alpha 1AT gene, it is recognized that, for unknown reasons, there are also increased numbers of neutrophils in their lungs compared with normal individuals. With the knowledge that alveolar macrophages have surface receptors for neutrophil elastase, we hypothesized that the neutrophil accumulation in the lower respiratory tract in alpha 1AT deficiency may result, in part, from release of neutrophil chemotactic activity by alveolar macrophages as they bind uninhibited neutrophil elastase. Consistent with this hypothesis, alpha 1AT-deficient alveolar macrophages spontaneously released nearly threefold more neutrophil chemotactic activity than normal alveolar macrophages. Analysis of alpha 1AT-deficient macrophage supernates by reverse-phase HPLC, molecular sieve chromatography, radioimmunoassay, and absorption with anti-LTB4 antibody revealed that the majority of the chemotactic activity was leukotriene B4 (LTB4), a mediator absent from normal macrophage supernates. Consistent with this hypothesis, incubation of normal macrophages with human neutrophil elastase resulted in the release of the same neutrophil chemotactic mediator. Furthermore, purified human alpha 1AT was able to prevent the neutrophil elastase from stimulating the macrophages to release the chemotactic factor. Together, these findings suggest that the absence of a normal antineutrophil elastase screen in the lower respiratory tract permits free neutrophil elastase to bind to alveolar macrophages, resulting in the release of LTB4, a process which attracts neutrophils to the alveoli of alpha 1AT deficient individuals, thus accelerating the lung destruction that characterizes this disorder.