Normative values of the motor competence assessment (MCA) from 3 to 23 years of age

ObjectivesGrowing evidence of the importance of motor competence for developing a healthy lifestyle has been established in the last decade. Nonetheless, no single instrument or observation tool have been able to fully measure this construct, particularly because most were built for the diagnosis of children in risk for motor impairment; are limited to a few years of the developmental span; lack objectivity in the assessment protocols; or do not include the locomotor, stability, and manipulative components. This led to the difficulty of comparing researches, and longitudinally follow children into adulthood. Recently, a novel proposal to assess motor competence was presented - the Motor Competence Assessment (MCA) - and this study aims to present the MCA normative data from 3-to-23 years.Design and methodsTwo thousand and eighty-seven participants (1102 boys) between 3 and 23 years of age were evaluated in the MCA (standing long jump, 10 m shuttle run, throwing velocity, kicking velocity, lateral jumps, shifting platforms). Results for each test were introduced in the LMS Chartmaker 2.3. The best model for test and sex was used, resulting in normative curves and percentile values.ResultsFinal norms showed a good fit to the instrument developmental expectations, allowing to differentiate and classify performances along the age interval.ConclusionsThe MCA age- and sex- normative values allow to assess motor competence from childhood to early adulthood. Future directions will include obtaining a total MCA score and the normative scores for the MCA components (stability, locomotion, object control), and to expand the norms to adulthood and old age.     

Multi-segment spine kinematics: Relationship with dance training and low back pain

BackgroundSpine posture, range of motion (ROM) and movement asymmetry can contribute to low back pain (LBP). These variables may have greater impact in populations required to perform repetitive spine movements, such as dancers; however, there is limited evidence to support this.Research questionWhat is the influence of dance and LBP on spinal kinematics?MethodsIn this cross-sectional study, multi-segment spinal kinematics were examined in 60 female participants, including dancers (n = 21) and non-dancers (n = 39) with LBP (n = 33) and without LBP (n = 27). A nine-camera motion analysis system sampling at 100 Hz was used to assess standing posture, as well as ROM and movement asymmetry for side bend and trunk rotation tasks. A two-way ANOVA was performed for each of the outcome variables to detect any differences between dancers and non-dancers, or individuals with and without LBP.ResultsCompared to non-dancers, dancers displayed a flatter upper lumbar angle when standing (p < 0.01, ηp² = 0.15), and achieved greater frontal plane ROM for the upper lumbar (p = 0.04, ηp² = 0.08) and lower thoracic (p = 0.02, ηp² = 0.09) segments. There were no differences between dancers and non-dancers for transverse plane ROM (p > 0.05) or movement asymmetry (p > 0.05). There was no main effect for LBP symptoms on any kinematic measures, and no interaction effect for dance group and LBP on spinal kinematics (p > 0.05).SignificanceFemale dancers displayed a flatter spine posture and increased spine ROM compared to non-dancers for a select number of spine segments and movement tasks. However, the overall number of differences was small, and no relationship was observed between LBP and spinal kinematics. This suggests that these simple, static posture, ROM, and asymmetry measures often used in clinical practice can provide only limited generalisable information about the impact of dance or LBP on spinal kinematics.     

Relationship between lower limb muscle strength and hallux valgus severity in older people

ObjectiveTo examine differences in lower limb muscle strength between older people with varying degrees of hallux valgus deformity.MethodsMuscle strength was measured at the knee, ankle and foot using hand-held dynamometry and a clinical test of toe strength (the paper grip test) in 157 older people (99 women and 58 men) aged 65 to 91 (mean 74.1, SD 5.9) years. Hallux valgus severity was documented as none, mild, moderate or severe using validated photographs. Differences in muscle strength according to hallux valgus severity were evaluated using analysis of variance, adjusting for age. Paper grip test performance was compared across the hallux valgus severity groups using the chi-square (χ²) statistic.ResultsKnee extension, ankle joint dorsiflexion, ankle joint plantar flexion, ankle joint inversion, ankle joint eversion and lesser toe plantarflexion strength were not significantly different across the four hallux valgus severity groups. However, there was a significant, dose-response reduction in hallux plantarflexion strength with increasing severity of hallux valgus. This persisted after adjustment for age (F₃ = 5.5, p = 0.001) with a medium effect size (partial η² = 0.10). The number of participants who could successfully complete the paper grip test of the hallux significantly reduced across the four hallux valgus categories (χ² = 18.5, p < 0.001).ConclusionsThere is a specific and progressive reduction in hallux plantarflexion strength with increasing severity of hallux valgus in older people. This finding has potential implications for both the aetiology and treatment of this common and disabling condition.     

Influence of posture on blink reflex prepulse inhibition induced by somatosensory inputs from upper and lower limbs

BackgroundPrepulse inhibition (PPI) is a neurophysiological phenomenon whereby a weak stimulus modulates the reflex response to a subsequent strong stimulus. Its physiological purpose is to avoid interruption of sensory processing by subsequent disturbing stimuli at the subcortical level, thereby preventing undesired motor reactions. An important hub in the PPI circuit is the pedunculopontine nucleus, which is also involved in the control of posture and sleep/wakefulness.ObjectiveTo study the effect of posture (supine versus standing) on PPI, induced by somatosensory prepulses to either upper or lower limb. PPI was measured as the percentage inhibition of the blink reflex response to electrical supraorbital nerve (SON) stimulation.MethodsSixteen healthy volunteers underwent bilateral blink reflex recordings following SON stimulation either alone (baseline) or preceded by an electrical prepulse to the median nerve (MN) or sural nerve (SN), both in supine and standing. Stimulus intensity was 8 times sensory threshold for SON, and 2 times sensory threshold for MN and SN, respectively. Eight stimuli were applied in each condition.ResultsBaseline blink reflex parameters did not differ significantly between the two postures. Prepulse stimulation to MN and SN caused significant inhibition of R2. In supine but not in standing, R2 was significantly more inhibited by MN than by SN prepulses. In standing, SN stimulation caused significantly more inhibition of R2 than in supine, while the inhibition caused by MN prepulses did not differ significantly between postures.SignificancePPI induced by lower limb afferent input may contribute to postural control while standing.     

Body weight support through a walking cane in inexperienced users with knee osteoarthritis

BackgroundWalking canes are a self-management strategy recommended for people with knee osteoarthritis (OA) by clinical practice guidelines. Ensuring that an adequate amount of body-weight support (%BWS) is taken through the walking cane is important as this reduces measures of knee joint loading.Research question1) How much body weight support do people with knee OA place through a cane? 2) Do measures of body weight support increase following a brief simple training session?MethodsSeventeen individuals with knee pain who had not used a walking cane before were recruited. A standard-grip aluminum cane was then used for 1 week with limited manufacturer instructions. Following this, participants were evaluated using an instrumented force-measuring cane to assess body weight support (% total body weight) through the cane. Force data were recorded during a 430-metre walk undertaken twice; once before 10 min of cane training administered by a physiotherapist, and once immediately after training. Measures of BWS (peak force, average force, impulse equal to the average cane force times duration, and cane-ground contact duration) were extracted. Using bathroom scales, training aimed to take at least 10% body weight support through the cane.ResultsBefore training, the average peak BWS was 7.2 ± 2.5% of total body weight. Following 10 min of training, there was a significant increase in average peak BWS by 28%, average BWS by 25%, and BWS impulse by 54% (p < 0.05). However, individual BWS responses to training were variable. Duration of cane placement increased by 22% after training (p = 0.02). Timing of peak BWS through the cane occurred at 51% of contact phase before training, and at 53% after training (p = 0.05).SignificanceA short training session can increase the transfer of body weight through a walking cane. However, more sophisticated feedback may be needed to achieve target levels of BWS.     

Cognition in breast cancer survivors: A pilot study of interval and continuous exercise

Objectives

The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.

Intra-seasonal variation of injury patterns among German Bundesliga soccer players

ObjectiveHigh fluctuations in injury-risk during the playing season in soccer have been reported. As seasons are structured in periods with homogenous loads and intensities, we investigated injury-risk over season periods, contrarily to previous studies adopting a month-based approach.DesignCohort study; Level of evidence, 2.MethodsIncidence-rate ratios (IRRs) for match and training injuries were compared across six consecutive seasons of German Bundesliga, divided into six periods each: Pre-season (PS), winter-break (WB), quarter 1–4: (Q1–Q4).ResultsSignificant variations in injury-risk were observed for match and training injuries. IRRs in matches was 1.30 (95% CI: 1.11–1.53) times higher in Q3 and 1.53 (95% CI: 1.31–1.78) higher in Q4 compared to Q1. For training injuries, IRR peaked in Q1 and Q3 followed by a marked decrease in each subsequent quarter. Compared to Q4, IRR was 1.62 (95% CI: 1.40–1.86) times higher during Q3 and 1.78 (95% CI: 1.53–2.07) times higher in Q1. IRR was significantly higher in the competitive season compared to pre-season across match (IRR: 2.00, 95% CI: 1.30–3.00) and training (IRR: 1.27, 95% CI: 1.11–1.43) injuries.ConclusionsThe increased match IRRs later during the season indicate that, in practice, coaches should consider putting even more emphasis on recovery in the last part of the season. Moreover, training injuries seem to indicate a carry-over effect. Further studies need to investigate how training during preparatory phases can be implemented in a way that prevents injuries during the competitive season.