A systematic video analysis of 21 anterior cruciate ligament injuries in elite netball players during games

This systematic video analysis of 21 anterior cruciate ligament (ACL) injuries sustained by elite-level netball players during televised games, describes the situation, movement pattern and player behaviour, providing insight regarding the injury mechanism. Seventeen of the ACL injuries occurred from jump-landing actions and only two from cutting manoeuvres. A common scenario was identified for 11 players. In this scenario, players were decelerating rapidly after jumping to receive a high pass, utilising a double-footed landing with a wide base of support (WBOS). Deceleration appeared to be applied predominantly via the injured leg with the knee extended and foot planted. Often the players appeared unbalanced on landing leaning too far back. ACL injury risk was possibly exacerbated by the players head turning away from the injured side. A further compressive knee moment may have been placed on the lateral aspect of the knee by bringing the ball from a high position to a low position at the estimated time of injury. Players may benefit from landing technique training programmes that encourage shoulder-width foot landings, with ≥30° knee flexion, a small amount of plantar-flexion and good balance. Incorporating challenges to players balance and ability to cope with perturbations may also be beneficial. Training programmes should include instruction on securing the ball in a stable above pelvis-level position after receiving a pass and bringing their whole body around during landing into the direction of their next pass, rather than simply turning their head to look.

Short and long versions of a 12-week netball specific neuromuscular warm-up improves landing technique in youth netballers

OBJECTIVE

To investigate the efficacy of two 'NetballSmart', netball specific warm-ups in improving landing technique measures in New Zealand secondary school netball players.

DESIGN

Multi-site cluster experimental trial.

PARTICIPANTS

77 youth participants, mean ± SD age = 15.8 ± 0.9 were recruited from secondary school netball teams.

SETTING

12 teams from 6 schools performed either the NetballSmart Dynamic Warm-up (NSDW) (n = 37); or Power warm-up (PWU) (n = 40), three times a week for 12 weeks. All players within a school (2 teams) were assigned the same warm-up, avoiding treatment contamination.

MAIN OUTCOME MEASURES

A series of unilateral and bilateral drop vertical jumps on to a portable force plate were completed by all participants. Measures included peak vertical ground reaction force (GRF) for single-leg and bilateral landings; frontal plane projection angle (FPPA) for right and left single-leg landings and Landing error scoring system (LESS) for bilateral landings. Paired t-tests were used to assess mean differences pre and post the warm-up. Generalised linear mixed effects models were developed to evaluate the effects between the NSDW and PWU groups.

RESULTS

Significant improvements were found in all the landing technique outcome measures for both warm-up groups (ES Range- GRF = -0.6 to -1.1; FPPA = 0.8 to 1.2; LESS = -1.6 to-3.2; p < 0.05). Results of mixed effects models revealed that there was only a significantly greater improvement in LESS for the PWU group (β = -0.30, p = 0.001).

CONCLUSION

Results show both warm-ups can improve landing technique measures in youth secondary school netball players. It is recommended that coaches should consider implementing one of the two warm-ups in their netball programmes. Their choice of warm-up will likely be dependent on their environment and time demands.

Ten-year nationwide review of netball ankle and knee injuries in New Zealand

OBJECTIVES

To review netball ankle and knee injuries between 2008 and 2017.

DESIGN

Audit of insurance injury claims.

METHODS

Data were divided into 5 equal year groups (2008/9, 2010/11, 2012/13, 2014/15, 2016/17), and 3 age groups (10 to 14 years, 15 to 19 years, 20 to 24 years old). Raw injury counts and injury rates per 1000 affiliated players were reported. Changes in injury rates over the 10-year period and differences between age groups were expressed as Incident rate ratios (IRRs). A Shewhart control chart was created to identify monthly injury patterns.

RESULTS

10-14-year-olds showed the biggest increase in injury counts (ankle 84% increase and knee 133% increase). 20-24-year-olds had the highest mean injury rate over the ten-years (ankle = 77.8, knee = 71.6 injuries/1000 players). 10-14-year-olds had the biggest increase in risk of injury between 2008/09 to 2016/17, (ankle IRR = 2.0; knee IRR = 2.5), 15-19-year-olds (ankle IRR = 1.4; knee IRR = 1.5), 20-24 year olds (ankle IRR = 0.5; knee IRR = 1.9). The older two groups had a significantly higher mean risk of ankle and knee injury (IRR = 1.9 to 2.2; p < 0.001). Higher than expected yearly injury incidence was repeatedly seen in 10-19-year-olds.

CONCLUSION

Ankle and Knee injuries have increased with the biggest increase in 10-19-year-olds. Injuries in 20-24-year-olds still represent the highest cost and continue at a higher rate than in younger players. Spikes in injury are likely associated with intense periods of trialling and tournament play.

Exploration of a new model of care in a psychiatry unit

The model established at Orillia Soldiers Memorial Hospital involves family physicians as the most responsible physician. They act as "admission gatekeeper" for all unattached patients who are admitted to the psychiatry in-patient unit. A PubMed, EBSCO, OVID Medline, Embase, CINAHL, and Web of Science database review of the last 10 years (2006-2016) was undertaken. A satisfaction survey was undertaken. An intensive literature review found this model to be unique. The model has proved to be extremely efficient and cost-effective.

Introduction to the DAPPLE Air Pollution Project

The Dispersion of Air Pollution and its Penetration into the Local Environment (DAPPLE) project brings together a multidisciplinary research group that is undertaking field measurements, wind tunnel modelling and computer simulations in order to provide better understanding of the physical processes affecting street and neighbourhood-scale flow of air, traffic and people, and their corresponding interactions with the dispersion of pollutants at street canyon intersections. The street canyon intersection is of interest as it provides the basic case study to demonstrate most of the factors that will apply in a wide range of urban situations. The aims of this paper are to introduce the background of the DAPPLE project, the study design and methodology for data collection, some preliminary results from the first field campaign in central London (28 April-24 May 2003) and the future for this work. Updated information and contact details are available on the web site at http://www.dapple.org.uk.

Localization of the m2 muscarinic acetylcholine receptor protein and mRNA in cortical neurons of the normal and cholinergically deafferented rhesus monkey

The m2 muscarinic acetylcholine receptor in the cerebral cortex has traditionally been thought of as an autoreceptor located on cholinergic fibers that originate from neurons in the nucleus basalis of Meynert. We now provide evidence for widespread localization of the m2 receptor in noncholinergic neurons and fibers of the cerebral cortex. The cellular and subcellular distribution of the m2 receptor protein and mRNA were examined in normal monkeys and in monkeys in which the cortical cholinergic afferents were selectively lesioned by injection of the specific immunotoxin, anti-p75NTR-saporin into the nucleus basalis. Both in normal and immunolesioned monkeys, the m2 mRNA and protein were localized in pyramidal and nonpyramidal neurons. In pyramidal neurons, membrane-associated receptor immunoreactivity was found exclusively in dendritic spines receiving asymmetric synapses, indicating that the m2 receptor may modulate excitatory neurotransmission at these sites. In nonpyramidal neurons, the m2 immunoreactivity was present along the cytoplasmic surface of membranes in cell bodies, dendrites and axons. Both in pyramidal and nonpyramidal neurons of normal and lesioned monkeys, the m2 receptor was located peri- and extra-synaptically, suggesting that it may be contacted by acetylcholine via volume transmission. The localization of the m2 receptor in cortical neurons and the sparing of m2 immunoreactivity in lesioned monkeys indicates that the m2 receptor is synthesized largely within the cortex and/or is localized to noncholinergic terminals of either intrinsic or extrinsic origin. These findings open the possibility that the loss of the m2 receptor in Alzheimer's disease may in part be due to degenerative changes in m2 positive neurons of the cortex rather than entirely due to the loss of autoreceptors.

A new sodium channel alpha-subunit gene (Scn9a) from Schwann cells maps to the Scn1a, Scn2a, Scn3a cluster of mouse chromosome 2

We have used a total of 27 AXB/BXA recombinant inbred mouse strains to determine the chromosomal location of a newly identified gene encoding an alpha-subunit isoform of the sodium channel from Schwann cells, Scn9a. Linkage analysis established that Scn9a mapped to the proximal segment of mouse chromosome 2. The segregation of restriction fragment length polymorphisms in 145 progeny from a Mus spretus x C57BL/6J backcross indicates that Scn9a is very tightly linked to Scn1a (gene encoding the type I sodium channel alpha-subunit of the brain) and forms part of a cluster of four Scna genes located on mouse chromosome 2.

Examination of the esterified fatty acids from mouse erythrocyte and synaptosomal membrane phospholipids and their distribution between the various phospholipid types

Esterified fatty acids from mouse erythrocyte and synaptosomal membranes were characterised by fused-silica capillary gas-liquid chromatography and gas chromatography-mass spectrometry. Structural information was obtained from the mass spectra of a number of derivatives including trimethylsilyl (TMS), methyl and picolinyl esters together with the TMS ethers of glycols derived from the unsaturated acids. In addition to previously characterised acids, small concentrations of several acids previously unreported from these membranes were identified. These included branched chain acids and several unsaturated acids.

Direct measurement of propranolol bioavailability during accumulation to steady-state

1. A high performance liquid chromatographic method for the determination of propranolol in human plasma and blood has been developed and used to confirm that cumulation occurred during chronic oral administration, steady-state being achieved within 48 h of beginning 80 mg of the drug every 8 h. 2. The method was adapted to measure [H3]-propranolol and native drug in the same blood sample and was applied to determine simultaneously the disposition of i.v. ([H3]-propranolol) and orally (non-labelled) administered drug after single oral dose of 80 mg and when steady-state had been established on an 80 mg, 8-hourly regimen. 3. Using this approach it was possible to show that a reduced oral clearance at steady-state was associated with a smaller reduction in systemic (i.v.) clearance and no change in liver blood flow. A direct estimate of bioavailability was also possible and was found to be increased at steady-state compared with a single oral dose. 4. We conclude that the accumulation of propranolol during the attainment of steady-state is due to a reduction in intrinsic clearance, resulting in reduced presystemic hepatic extraction.