Influence of functional rider and horse asymmetries on saddle force distribution during stance and in sitting trot

Asymmetric forces exerted on the horse's back during riding are assumed to have a negative effect on rider–horse interaction, athletic performance, and health of the horse. Visualized on a saddle pressure mat, they are initially blamed on a nonfitting saddle. The contribution of horse and rider to an asymmetric loading pattern, however, is not well understood. The aim of this study was to investigate the effects of horse and rider asymmetries during stance and in sitting trot on the force distribution on the horse's back using a saddle pressure mat and motion capture analysis simultaneously. Data of 80 horse-rider pairs (HRP) were collected and analyzed using linear (mixed) models to determine the influence of rider and horse variables on asymmetric force distribution. Results showed high variation between HRP. Both rider and horse variables revealed significant relationships to asymmetric saddle force distribution (P < .001). During sitting trot, the collapse of the rider in one hip increased the force on the contralateral side, and the tilt of the rider's upper body to one side led to more force on the same side of the pressure mat. Analyzing different subsets of data revealed that rider posture as well as horse movements and conformation can cause an asymmetric force distribution. Because neither horse nor rider movement can be assessed independently during riding, the interpretation of an asymmetric force distribution on the saddle pressure mat remains challenging, and all contributing factors (horse, rider, saddle) need to be considered

Determining Objective Parameters to Assess Gait Quality in Franches-Montagnes Horses for Ground Coverage and Over-Tracking - Part 1: At Walk

Ground coverage and over-tracking are two gait quality traits describing the forward movement of the front respectively the hind limbs in relation to stride length and over-tracking distance. To investigate the complex interplay of different movement patterns in ground coverage and over-tracking, limb and body kinematics of 24 Franches-Montagnes (FM) stallions were measured with 3D optical motion capture (OMC) on a treadmill during an incremental speed test at the walk (1.4-2.0 m/s). The significance and amount of explained variance of kinematic parameters on stride length and over-tracking distance were estimated using linear mixed-effect models, with speed and horse as random effects. Two separate models were tested: a full model with all parameters measurable by OMC, and a reduced model with a subset of parameters also measurable with inertial measurement units (IMUs). The kinematic parameters were correlated to the subjective scores from six breeding experts to interpret their external validity. The parameter for ground coverage at the walk, explaining most of the variance in stride length, were the maximal forelimb retraction angle (11%) measured with OMC, and the range of pelvis pitch (10%) if measuring with IMUs. The latter was also the most relevant for quantifying over-tracking, explaining 24% to 33% of the variance in the over-tracking distance. The scores from most breeding experts were significantly correlated (r ≥ |0.41|) with the fore- and hind limb protraction angles, which reflect the textual definition of ground coverage and over-tracking. Both gait quality traits can be objectively quantified using either OMC or IMUs

Withers vertical movement asymmetry in dressage horses walking in different head -neck positions with and without riders

The superimposed influences of different head and neck positions (HNPs) and rider effects on symmetry in sound horses have not been studied. Our aim was to investigate the effects of HNPs and rider on thesymmetry in minimum height of the withers at the walk. Seven high-level dressage horses were studied with and without rider in six HNPs: HNP1, free position; HNP2, dressage competition position; HNP3,flexed poll position; HNP4, over-flexed position; HNP5, extended raised position; and HNP6, forward downward position. Kinematic and vertical ground reaction force data were recorded during 15 s trialson an instrumented treadmill. In mixed models, difference in the minimal height of the withers in earlyleft vs right forelimb stance was modelled as dependent variable. The more restricted HNP3 (T-values2.62 to 1.98, 118 DF,P¼0.001 to<0.05) and HNP5 (P¼0.002 to<0.05) were generally less symmetrical while unridden and more symmetrical while ridden, compared with the free (HNP1) or forward downward (HNP6) positions. Both with and without rider, when the withers dropped lower in earlystance of one forelimb, this was associated with shorter protraction at the start of stance in the ipsilateral hind limb, and shorter stance overlaps between this hind limb and the other limbs during diagonalsupport, 3-limb support with two forelimbs and one hind limb, and ipsilateral support. HNP effects on withers movement asymmetry differed between unridden and ridden conditions. The considerablevariation between horses stresses the need for trainers to use individualized training programs to address horse asymmetry

Adaptation strategies of horses with induced forelimb lameness walking on a treadmill

Background There is a paucity of research describing the gait pattern of lame horses at the walk. Objectives To describe the changes in motion pattern and vertical ground reaction forces (GRFz) in horses with induced forelimb lameness at the walk and compare those changes with the changes observed at the trot. Study design Experimental study. Methods In 10 clinically sound Warmblood horses, moderate forelimb lameness was induced using a sole pressure model followed by trot and walk on a treadmill. Kinematic data were collected using 3D optical motion capture (OMC), and GRFz by an instrumented treadmill. Mixed models were used to compare sound baseline versus forelimb lameness (significance was set atP < .05). Results Lameness induction significantly reduced peak GRFz on the second force peak, and vertical impulse in the lame limb. Stride and stance duration in all limbs were reduced. Lameness significantly affected the vertical movement symmetry of the head and withers. Maximum limb retraction angle, fetlock extension and protraction speed were reduced in the lame limb. Body centre of mass (COM) translation was reduced in the side-to-side direction and increased in the vertical and fore-aft directions. Several compensatory kinetic and kinematic changes were observed in the nonlame limbs. The observed changes in both kinetics and kinematics were generally smaller at walk with fewer variables being affected, compared to the trot. Main limitations Only one degree and type of orthopaedic pain (sole pressure) was studied. Conclusions Compensatory strategies of forelimb lameness at the walk include alteration of several kinetic and kinematic parameters and have some specific patterns and inter-individual differences that are not seen at the trot. However, much like at the trot, head movement and forelimb vertical force symmetry seem to be the most useful parameters to detect forelimb lameness at walk

Findings and interobserver agreement in radiography and ultrasonography of the vertebral column of a large population of normally performing horses

Diagnostic imaging is a mainstay in the investigation of equine neck and back pain, but interpretation of radiographic and ultrasonographic findings in the spinal column of horses is not straightforward for a variety of reasons including individual anatomical variations, progressive degenerative nature of most pathologies and superimposition as well as technical limits. These issues are even more relevant in the context of examinations of apparently sound horses with absent, mild or unclear complaints, like it is often the case in pre-purchase examinations or cases of failure to meet expected performance. The first aim was to report on the spectrum, degree and location of first-line imaging findings in the spine of a large population of normally performing horses. Limited data is available about agreement of interpretation of equine vertebral column imaging by radiologists. The second aim of this prospective study was to determine interobserver agreement on radiographic and ultrasonographic diagnostic imaging findings in the vertebral column of the same population between multiple observers with longstanding experience in equine diagnostic imaging at two different institutions. Seventy-one horses randomly selected from a larger population of 250 normally performing horses participating in a swiss project on equine back health were examined at one referral center. Radiographic and ultrasonographic examinations were performed in a standardized fashion and images graded separately by two experienced radiologists at two different institutions. Focus was placed on osteoarthrosis of the synovial intervertebral articulations (SIVAs), impinging and overriding of the spinous processes (SPs) and spondylosis. Cohen’s weighted kappa was calculated for each pathology, location and segment in each modality. Interobserver agreement was calculated for findings at specific locations, single pathologies and single grades. Most horses showed no changes and were allocated grades 0 at most locations. Few abnormalities were found throughout the vertebral column, with clusters of abnormalities of the SIVAs in the caudal cervical segment and cranial lumbar segment as well as a cumulation of changes at the dorsal spinous processes in the caudal thoracic segment. These coincide with previously reported predilection sites of imaging findings in symptomatic populations. Overall mean value of agreement for imaging findings was moderate (k= 0.7). Agreement was moderate for imaging findings regarding the synovial intervertebral articulations of the thoracolumbar spine in radiography (k=0.66) but weak in ultrasonography (k=0.58). There was moderate agreement in the imaging findings of the cervical spine in ultrasonography (k=0.61) as well as radiography (k=0.62). Strong agreement was found in the radiographic assessment of changes of the thoracolumbar spinous processes (k=0.80). Almost perfect agreement was found in the radiographic assessment of thoracolumbar spondylosis (k=0.95). Agreement between radiologists in detection and grading of pathologies of the equine vertebral column is weak to almost perfect depending on pathology and location. Our results confirm findings about distribution of specific pathologies found in other studies and support the importance of interpreting imaging findings along with clinical findings for definitive case management and decision making. Additional studies are needed for determination of the correlation of imaging findings among different modalities and correlation of diagnostic imaging with clinical findings

A semi-synthetic oligosaccharide conjugate vaccine candidate confers protection against Streptococcus pneumoniae serotype 3 infection

The identification of immunogenic glycotopes that render glycoconjugate vaccines protective is key to improving vaccine efficacy. Synthetic oligosaccharides are an attractive alternative to the heterogeneous preparations of purified polysaccharides that most marketed glycoconjugate vaccines are based on. To investigate the potency of semi-synthetic glycoconjugates, we chose the least-efficient serotype in the current pneumococcal conjugate vaccine Prevnar 13, Streptococcus pneumoniae serotype 3 (ST3). Glycan arrays containing synthetic ST3 repeating unit oligosaccharides were used to screen a human reference serum for antibodies and to define the recognition site of two ST3-specific protective monoclonal antibodies. The glycan array screens identified a tetrasaccharide that was selected for in-depth immunological evaluation. The tetrasaccharide-CRM197 carrier protein conjugate elicited protective immunity as evidenced by opsonophagocytosis assays and protection against pneumonia caused by ST3 in mice. Formulation of the defined protective lead candidate glycotope has to be further evaluated to elicit optimal long-term immunity

The contested and contingent outcomes of Thatcherism in the UK

The death of Margaret Thatcher in April 2013 sparked a range of discussions and debates about the significance of her period in office and the political project to which she gave her name: Thatcherism. This article argues that Thatcherism is best understood as a symbolically important part of the emergence of first-phase neoliberalism. It engages with contemporary debates about Thatcherism among Marxist commentators and suggests that several apparently divergent positions can help us now reach a more useful analysis of Thatcherism’s short- and long-term outcomes for British political economy. The outcomes identified include: an initial crisis in the neoliberal project in the UK; the transformation of the party political system to be reflective of the politics of neoliberalism, rather than its contestation; long-term attempts at the inculcation of the neoliberal individual; de-industrialisation and financial sector dependence; and a fractured and partially unconscious working class. In all long-term outcomes, the contribution of Thatcherism is best understood as partial and largely negative, in that it cleared the way for a longer-term and more constructive attempt to embed neoliberal political economy. The paper concludes by suggesting that this analysis can inform current debates on the left of British politics about how to oppose and challenge the imposition of neoliberal discipline today

Sirolimus and kidney growth in autosomal dominant polycystic kidney disease

BACKGROUND: In autosomal dominant polycystic kidney disease (ADPKD), aberrant activation of the mammalian target of rapamycin (mTOR) pathway is associated with progressive kidney enlargement. The drug sirolimus suppresses mTOR signaling. METHODS: In this 18-month, open-label, randomized, controlled trial, we sought to determine whether sirolimus halts the growth in kidney volume among patients with ADPKD. We randomly assigned 100 patients between the ages of 18 and 40 years to receive either sirolimus (target dose, 2 mg daily) or standard care. All patients had an estimated creatinine clearance of at least 70 ml per minute. Serial magnetic resonance imaging was performed to measure the volume of polycystic kidneys. The primary outcome was total kidney volume at 18 months on blinded assessment. Secondary outcomes were the glomerular filtration rate and urinary albumin excretion rate at 18 months. RESULTS: At randomization, the median total kidney volume was 907 cm(3) (interquartile range, 577 to 1330) in the sirolimus group and 1003 cm(3) (interquartile range, 574 to 1422) in the control group. The median increase over the 18-month period was 99 cm(3) (interquartile range, 43 to 173) in the sirolimus group and 97 cm(3) (interquartile range, 37 to 181) in the control group. At 18 months, the median total kidney volume in the sirolimus group was 102% of that in the control group (95% confidence interval, 99 to 105; P=0.26). The glomerular filtration rate did not differ significantly between the two groups; however, the urinary albumin excretion rate was higher in the sirolimus group. CONCLUSIONS: In adults with ADPKD and early chronic kidney disease, 18 months of treatment with sirolimus did not halt polycystic kidney growth. (ClinicalTrials.gov number, NCT00346918.