Carbon footprint of tonsillectomy.

BACKGROUND AND PURPOSE: Healthcare is responsible for 5.4% of greenhouse gas emissions in the UK. Emissions in surgery is a relatively unexplored area; in particular, this hasn't yet been looked at as a whole in ENT in the UK. The purpose of the study was to quantify the amount of greenhouse gas (GHG) emission from a tonsillectomy and assess the proportion of each source's contribution. METHODS: Operational data from tonsillectomies performed at a large university teaching hospital in the UK were gathered and converted to global warming potential using established conversion factors and data from existing healthcare-focused carbon footprint studies. The domains considered were waste, pharmaceuticals, surgical instrument decontamination, transportation, consumables use and utilities. This study used a process-based carbon footprint approach based on the "Greenhouse Gas Protocol: Product Life Cycle Accounting and Reporting Standard". MAIN FINDINGS: The carbon footprint of a typical case was 41 kgCO2e which is equivalent to driving a car for approximately 150 miles. Consumables were responsible for 17% of this; 14% came from transport, 5.4% from decontamination, 4.8% from pharmaceuticals and 4% from waste. However, the largest GHG was from utilities, of which heating, ventilation and air conditioning was the overwhelming contributor. CONCLUSIONS: While the largest sources of GHG emissions require hospital-wide initiatives, there are aspects of consumables and waste streams we can improve on in ENT surgery. These include the use of disposable vs reusable instruments as well as increased availability and use of recycling waste streams in theatres. Additionally, this study provides a template that can be applied to other ENT procedures.

Total knee arthroplasty reduces knee extension torque in-vitro and patellofemoral arthroplasty does not.

Patients often have difficulty recovering knee extension strength post total knee arthroplasty (TKA), and that may reflect alteration of the mechanics including geometry and rollback kinematics, so the purpose of this work was to explore this by comparing the knee extension torque (KET) of the native knee, TKA and patellofemoral arthroplasty (PFA) in response to quadriceps tension. Eight fresh-frozen knees were mounted in a knee extension rig with quadriceps loading and tibial extension torque measurement. Each knee was subject to four conditions: native knee, PFA, cruciate-retaining (CR) and posterior-stabilized (PS) TKA. The KET was measured from 120° to 0° knee flexion. Data were analyzed using one-way ANOVA and post-hoc paired t-tests. The native KET was lowest in terminal extension and 70-100° flexion, and maximal at 20-30° flexion. PFA produced the greatest KET (p < 0.008) compared with native, CR- and PS-TKA, at 30-40° flexion. CR- and PS-TKA had lower KET across 0-50° flexion (p < 0.001 across 0-30°), falling to 25% of the native knee KET or the PFA at full extension. PFA had the highest KET in early flexion possibly due to increased trochlear offset and/or preservation of the cruciate mechanism, so PFA may be more beneficial during the functional range of motion. The claimed benefits of PS- over CR-TKA in deep flexion were not detected. Both CR- and PS-TKAs led to lower KET than the native and PFA knee states across 0-50° flexion. This mechanical effect may help to explain clinical findings of knee extension weakness post-TKA.

Intratympanic Gentamicin Versus Labyrinthectomy: Inner Ear Sensitivity to Gentamicin and Impact on the Contralateral Labyrinth.

OBJECTIVES: To investigate the impact of labyrinthectomy and intratympanic (IT) gentamicin injections on the contralateral labyrinth, we also assessed the response of each individual semicircular canal to each IT gentamicin application. METHODS: We performed a pilot observational study on tertiary, referral, academic settings. Thirteen patients with unilateral vestibular pathology were organized into two groups, group I (seven patients) receiving IT gentamicin and group II undergoing labyrinthectomy (six patients). All patients underwent six-canal video-head-impulse test in predetermined time intervals. Patients receiving gentamicin were additionally tested 3 to 5 days after every sequential injection, until all ipsilateral canals were ablated, to determine the order of response to gentamicin. We recorded the vestibular-ocular reflex gains and the presence of covert/overt saccades for each canal. RESULTS: The posttreatment ipsilateral gains were abnormal. No patient from the gentamicin group developed abnormal contralateral responses, while patients undergoing labyrinthectomy had abnormal contralateral responses from at least one canal, even several months posttreatment. Finally, the lateral semicircular canal was the first one to be affected by IT gentamicin followed by the posterior canal: the superior canal was ablated last. CONCLUSION: In our study, labyrinthectomy had an impact on the responses recorded from the contralateral ear, while IT gentamicin ablated the ipsilateral labyrinthine function without affecting the contralateral responses, possibly because of a milder, more gradual impact. We also show for the first time the order that IT gentamicin application affects the semicircular canals, with the lateral being the first to be affected.

Regulation of differentiation of mesenchymal stem cells into musculoskeletal cells.

Mesenchymal stem cells (MSCs) are multipotent cells that have the capability of differentiating into several different cells such as osteoblasts (bone), chondrocytes (cartilage), adipocytes (fat), myocytes (muscle) and tenocytes (tendon). In this review we highlight the different regulators which determine the lineage a particular MSC will differentiate into. Mesenchymal stem cells are increasingly being used in tissue regeneration and repair. Strict regulation of differentiation of MSCs is essential for a positive outcome of the particular tissue treated with MSCs, especially due to the fact that capacity to differentiate decreases with increasing age of the donor.

Sources of adult mesenchymal stem cells and their applicability for musculoskeletal applications.

There is significant potential for the use of adult mesenchymal stem cells in regenerating musckuloskeletal tissues. The sources of these stem cells discussed in this review are bone marrow, blood, adipose tissue, synovium, periosteum & cartilage. Adult mesenchymal stem cells of bone marrow origin are the cells which are heavily investigated in many studies and have been shown capable of producing a variety of connective tissues especially cartilage and bone. It has recently been suggested that bone marrow derived mesenchymal stem cells originate from microvascular pericytes, and, indeed, many of the tissues from which stem cells have been isolated have good vascularisation and they may give a varied source of cells for future treatments. Clinical trials have shown that these cells are able to be successfully used to regenerate tissues with good clinical outcome. Other sources are showing promise, however, is yet to be brought to the clinical level in humans.

Gaucher disease: outcome following total hip replacements and effect of enzyme replacement therapy in a cohort of UK patients.

Only a limited number of reports of total hip replacements (THRs) in patients with Gaucher disease (GD) have been published, with the majority showing high rates of early aseptic loosening as well as an increased number of peri-operative complications. We present a series of twelve THRs in nine affected patients, with a mean age of 39 years at the time of surgery (median 37 years; range 27-60 years). We examine the medium- to long-term results and present the outcome scores, survival, and assess the effect of enzyme replacement therapy (ERT). Four hips (33.3%) required revision for aseptic loosening at a mean time of 11.5 years. There was no significant difference in survival between the group on ERT at the time of surgery and group not on ERT. Those on ERT did, however, have fewer peri-operative complications and there was a trend to better outcome scores. Five of the 12 THRs were performed when the diagnosis of GD was unknown and all of these had early complications.?Our results show better survival of THRs in patients with GD than previously thought. The use of ERT pre-operatively did not have an effect on survival, nor outcome scores, but did reduce the peri-operative complication rate. Those not on ERT at the time of surgery were commenced on it at some point in their treatment (at an average of 8.6 years following THR) and we believe the use of ERT, at any time in the treatment, could have contributed to the improved survival seen in our series compared to historical results in the literature.

Management of anticoagulation therapy in the perioperative patient.

With the increasing use of oral anticoagulation therapy the appropriate management of perioperative anticoagulation is of surgical importance. There is a delicate balance between the risk of a perioperative thromboembolic event and the risk of operative bleeding from anticoagulation. Whilst there are a range of options available to the clinician, there appears to be no precise agreement about how to best manage this problem.

Advances and developments in the use of human mesenchymal stem cells - a few considerations.

One less visited area in musculoskeletal stem cell research is the effects of donor age on quality of stem cells. The prevalence of degenerative orthopaedic conditions is large, and the older population is likely to receive great benefit from stem cell therapies. There are many known growth factors involved in controlling and influencing stem cell growth which are also related to cell senescence. Of which, expressions are found to be altered in mesenchymal stem cells from older donors. Considerations must also be taken of these mechanisms which also have a role in cell cycle and tumour suppression.

The use of growth factors and mesenchymal stem cells in orthopaedics.

Stem cell therapy is an exciting and upcoming branch of tissue engineering with application in the field of orthopaedics. The most commonly used type of stem cells, mesenchymal stem cells (MSCs), can be easily isolated from bone marrow or synovium and cultured in vitro. Newer techniques using tissue engineering to regenerate musculoskeletal tissue by using biomimetic materials are now being studied. These osteoconductive three dimensional constructs seeded with MSCs are highly porous, biodegradable and biomechanically stable scaffolds which do not evoke an immunogenic host cell response. Research has shown the importance of growth factors in guiding and modulating the differentiation of MSCs in order to obtain the required cell type. Gene-based delivery systems have aided the delivery of sustained quantities of these growth factors. The evidence from growth factor enhanced tissue engineering studies for tissue healing looks very positive. This is a multi-disciplinary approach that integrates molecular, biochemical and clinical techniques with developmental and engineering processes. Initial studies indicate an immense potential for cell based strategies to enhance current orthopaedic approaches in skeletal tissue reconstruction. Ultimately, there is a need for randomised controlled trials on human populations to apply these findings to a clinical setting. Nevertheless, stem cell based tissue engineering in orthopaedics shows a promising future.

Bearing couples in total hip arthroplasty.

Total hip arthroplasty is a well-established treatment for arthritis of the hip. The choice of bearing couple used for articulation should be tailored to the patient. This article reviews the history of different bearing surfaces, and outlines the advantages and disadvantages that may influence their use.