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The purpose of this study was to examine the reliability of a new upper body medicine ball push-press (MBP-P) test. Twenty- three strength trained volunteers performed a series of supine MBP-P throws using loads representing 5% and 10% of their 5RM bench press (5 repetitions at each load). Throws were performed on a force platform (2000 Hz), with medicine ball kinematic data collected using a high-speed motion capture (500 Hz). Testing was repeated after 7-10 days to quantify intertest reliability. Maximal force (Fmax), impulse at Fmax, time to Fmax, and maximum rate of force development (RFDmax) were all calculated from the force platform outputs, with maximum ball velocity (Velmax) and maximum ball acceleration (Accelmax) developed from the kinematic data. Reliability was assessed using intraclass correlation (ICC), coefficient of variation (%CV), and typical error. Medicine ball kinematic variables were more reliable (CV% = 2.6-5.3, ICC = 0.87-0.95) than the various force platform derived power variables (CV% = 7.9-26.7, ICC = 0.51-0.90). The MBP-P test produces reliable data and can be used to quantify many standard power based measures, with the key findings have implications for athletic populations requiring high velocity, light load upper body pushing power. [ABSTRACT FROM AUTHOR]

In Australian rules football structured increases in ball size during development end with the transition to the Size 5 (adult) ball at the Under-15 age group. This study assessed changes in kick technique and performance in experienced junior performers when using Size 4 and 5 Australian rules footballs. Participants (n = 22, 13.77 ± 0.61 years) performed drop punt kicks in 2 representative tasks; a Decision-Making Test (DMT) (n = 14) and Set-Shot Test (SST) (n = 14 + 8). Results indicate participants sustained their level of kick performance (accuracy and quality of ball spin) in both tests when using a Size 5 football. Sustained kick performance in the DMT primarily resulted from adaptations to time-point technical measures at ball release. No significant differences were detected for technical measures between ball sizes in the SST. A dynamic kicking task (DMT) in combination with ball size manipulation may have placed greater demand on skill execution in comparison to a self-paced kicking task (SST). Results provide initial support for the utility of challenging representative dynamic and self-paced tasks, such as the DMT and SST used here for Australian football, for skill testing and practice in sport [ABSTRACT FROM PUBLISHER]

Aims: The aim of this study is to (1) compare and contrast cervical subtype classification methods within an asymptomatic population, and (2) identify inter-methodological consistencies and describe examples of inconsistencies that have the potential to affect subtype classification and clinical decision-making. Methods: A total of 150 asymptomatic 18-30-year-old participants met the strict inclusion criteria. An erect neutral lateral radiograph was obtained using standard procedures. The Centroid, modified Takeshima/Herbst methods and the relative rotation angles in cases of nonagreement were used to determine subtype classifications. Cohen's kappa coefficient (κ) was used to assess the level of agreement between the two methods. Results: Nonlordotic classifications represented 66% of the cohort. Subtype classification identified the cohort as, lordosis (51), straight (37), global kyphosis (30), sigmoidal (13), and reverse sigmoidal (RS) (19). Cohen's kappa coefficient indicated that there was only a moderate level of agreement between methods (κ = 0.531). Methodological agreement tended to be higher within the lordotic and global kyphotic subtypes whereas, straight, sigmoidal, and RS subtypes demonstrated less agreement. Conclusion: This is the first study of its type to compare and contrast cervical classification methods. Subtypes displaying predominantly extended or flexed segments demonstrated higher levels of agreement. Our findings highlight the need for establishing a standardized multi-method approach to classify sagittal cervical subtypes. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether differences in putting accuracy in highly skilled golfers could he explained by functional variability. Ten, male single-figure handicap golfers completed 18 two-metre putts. The position of the putter was recorded using a three-dimensional motion capture system. The results from regression analyses revealed that the more accurate participants exhibited greater variability in the swing path of the putter across test trials, suggesting that putting proficiency in highly skilled individuals may be explained, in part, by a greater capacity to adapt the stroke through the use of functional variability. There was also evidence to suggest that all participants, irrespective of their putting accuracy, exhibited reduced movement variability at the point at which the putter head made contact with the ball, relative to the variability of the putter head at the end of the backswing. [ABSTRACT FROM AUTHOR]

The application of aquatic therapy for health and rehabilitation purposes has been promoted for centuries. Although used predominantly in clinical settings for the treatment, rehabilitation and management of chronic conditions, the practice is also gaining popularity in athletic settings in such areas as recovery training and for the rehabilitation of acute musculoskeletal injuries. To date, most studies on the impact of aquatic-based rehabilitation on the human body have focused on physiological aspects. There is a relative paucity of published research on the biomechanical implications associated with aquatic-based activity. The published findings have been limited to the influence of the aquatic environment on running and walking gait. A clear challenge in this field is absence of standardised protocols for assessing the impact of aquatic therapy and its possible role in rehabilitation. For example, methodologies often differ considerably between studies, and there are no standardised reporting procedures for important variables such as water depth and temperature. The research knowledge in this area has been questioned, with current medical guidelines highlighting that high quality research into the roles of aquatic therapy in rehabilitation is warranted. This review will summarise the current literature on water-based activity and how this can impact human movement and subsequent rehabilitation. [ABSTRACT FROM AUTHOR]

Background. Preemployment testing is utilized by many ambulance services. Surprisingly, there is limited published research on the efficacy of this testing in determining an employee's ability to complete the requirements of this physically demanding occupation. Objectives. The purpose of this study was to analyze the preemployment fitness test results from a 4-year cohort of paramedic students from an Australian university. To date, no published studies have reported on the fitness test scores for paramedic students or on whether overall test score is biased toward any particular test components. Similarly, no data have been presented on whether there are gender differences in scores for individual test components or overall test score. Methods. Retrospective cohort study of de-identified data from 4 years of data from Paramedic Science students ( n = 251) (mean age = 24.9 years). Data were recorded from the Queensland Ambulance Service (QAS) Health Related Fitness Test (HRFT), a preemployment fitness test used by an Australian state ambulance service. HRFT score is calculated out of a possible 100 points and is based on performance scores in nine component fitness tests. Raw test scores for each of these component tests are ranked on a 0-4 scale prior to these data being scaled and summed to generate the overall HRFT score. An overall score >24.99 is awarded a 'Pass.' Results. Five individuals failed to 'Pass' the HRFT. Overall HRFT scores were influenced significantly by performance in the strength tests, with males also recording significantly ( p < 0.005) higher scores in all of the strength tests than females. Similarly, approximately 40% of the female participants, compared to 6% of males, achieved an overall test 'Pass' and yet gained a ranked score of 0 in at least three of the component tests. Conclusions. It was concluded that the scoring system did not exclude participants with poor fitness levels, as many participants recorded low scores in several test components yet still passed the test. We recommend that before redesigning the HRFT, studies should be first conducted on the occupational demands and physical standards required for this important profession. [ABSTRACT FROM AUTHOR]

Stroke-coordination and symmetry influence the force fluctuations within any net drag force profile. The aim of this study was to analyse elite (FINA points 938) backstroke swimmers stroke-coordination using an instantaneous net drag force and timing protocols using a symmetry index tool. Ten male and nine female elite backstroke swimmers completed three maximum speed trials and five maximum speed net drag force swimming trials. Net drag force was measured using an assisted motorised dynamometer device. Each trial was filmed using three genlocked 50 Hz cameras, synchronised to the net drag force output from the force-platform. This methodology enabled the comparison of stroke-coordination timing symmetry index to net drag force symmetry index. The timing symmetry index and net drag force symmetry index yielded different results, the timing reflects the stroke-coordination, whilst the force index identified the effectiveness of the stroke. The only variable that was significantly different when comparing left and right stroke patterns was the location of minimum net drag forces. Conversely, gender influenced the location of maximum net drag force. Relationship analysis identified that location of maximum net drag force production was the only variable to correlate with speed within this cohort. Backstroke arm coordination was minimally influenced by gender. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to evaluate changes in the three dimensional lower limb kinematics during a simulated cycling time trial.Design: Repeated measures.Methods: Ten experienced male road cyclists performed a 60 min cycling test at a workload based on previous onset of blood lactate accumulation (OBLA) testing. The time trial (TT) was divided into six 10 min periods consisting of 8 min cycling at steady state (88% of OBLA) followed by a 90 s effort phase (140% of OBLA) and a 30 s recovery phase (60% of OBLA). Three-dimensional kinematic data (200 Hz) were recorded in the last minute of each steady state phase with specific attention directed at changes in range of motion (ROM) and consistency of orientation at the hip, knee and ankle joints during drive phase.Results: from repeated measures ANOVA indicated a mean effect for test duration on the drive phase ROM in both hip extension (p=0.027) and ankle dorsi flexion (p<0.001). The SD of the mean tibial rotation during the drive phase was the only measure of movement consistency that showed an effect for test duration (p=0.031).Conclusions: These findings indicated that participants tended to increase the ROM in hip extension and ankle flexion during drive phase at the end of a TT. Changes in the consistency of tibial rotation during the drive phase may be an important indicator of fatigue and should be monitored by coaches during training due to its possible relationship with injury and fatigue. [ABSTRACT FROM AUTHOR]

The rugby union line-out is a key aspect of game play and involves players from both teams contesting for the ball after it has been thrown in from the side line. Successful lines-out throws require the ball to be delivered accurately to the hands of a jumping and/or lifted team mate (approximately 3-3.5 m off the ground) over distances of between 5-18 m. Previous research has suggested considerable inter and intra-individual differences in the throwing techniques of international level players. Accordingly, this project investigated the interrelationships between accuracy and the line-out throwing characteristics of three elite international rugby players, and then analyzed whether these changed for throws over increasing length. Threedimensional (3D) data were developed from video footage (50 Hz) of three elite international subjects for 30 throws over three distances (6 m, 10 m, and 15 m). Results showed notable differences between subjects in many variables at each of the key throw phases. However, several variables such as the degree of trunk flexion at the end of the backswing and at ball release, coupled with elbow flexion angle at ball release remained constant as throw length increased. All subjects exhibited high levels of consistency in movement patterns across all throw lengths. Findings indicated that these high performance line-out throwers shared several common characteristics that will provide useful guides in the development of training programs. [ABSTRACT FROM AUTHOR]

Rugby union is a collision sport where evasive agility running patterns and the tackle contest determine the effectiveness of attacking ball carries. This study used three-dimensional kinematic analysis to examine the running technique of eight highly trained rugby union players during three rugby based reactive (in response to a defender positioned at the side-step) agility conditions (non-contact, contact and fend). The fend condition involved pushing a defender away with the upper body during the side-step and both fend and contact conditions required impact with an additional defender at the straighten-step, simulating a rugby tackle. Results demonstrated that a reduction in the relative height of the centre of mass relative to standing height (%CM) occurred at the straighten-step during the contact condition (47.2 ±1.9 %CM) compared to the noncontact condition (49.1 ±1.8 %CM, p <.001). The fend condition was then shown to increase %CM at the straighten-step (48.4 ±2.7 %CM) when compared to the contact condition (47.2 ±1.9 %CM, p = .017). However this difference was not observed at tackle impact during the straighten-step, with similar %CM values for fend (45.1 ±3.4 %CM) and contact conditions (44.6 ±2.6 %CM, p = .205). Further analysis showed that the number of steps displayed between the side-step and straighten-step (transition phase) altered the %CM, with one step during the transition phase increasing %CM (49.3 ±1.5 %CM) compared to two transition phase steps (46.9 ±1.6 %CM, p < .001) and no transition phase steps (46.5 ±1.6 %CM, p < .001). The changes to running technique during agility conditions involving tackle situations highlight the need for running programs in rugby union to meet the specific requirements of match-play activities. [ABSTRACT FROM AUTHOR]

Three-dimensional kinematic analysis examined agility running technique during pre-planned and reactive performance conditions specific to attacking ball carries in rugby union. The variation to running technique of 8 highly trained rugby union players was compared between agility conditions (pre-planned and reactive) and also agility performance speeds (fast, moderate and slow). Kinematic measures were used to determine the velocity of the centre of mass (COM) in the anteroposterior (running speed) and mediolateral (lateral movement speed) planes. The position of foot-strike and toe-off was also examined for the step prior to the agility side-step (pre-change of direction phase) and then the side-step (change of direction phase). This study demonstrated that less lateral movement speed towards the intended direction change occurred during reactive compared to pre-planned conditions at pre-change of direction (0.08 ± 0.28 m·s-1 and 0.42 ± 0.25 m·s-1, respectively) and change of direction foot-strikes (0.25 ± 0.42 m·s-1 and 0.69 ± 0.43 m·s-1, respectively). Less lateral movement speed during reactive conditions was associated with greater lateral foot displacement (44.52 ± 6.10% leg length) at the change of direction step compared to pre-planned conditions (41.35 ± 5.85%). Importantly, the anticipation abilities during reactive conditions provided a means to differentiate between speeds of agility performance, with faster performances displaying greater lateral movement speed at the change of direction foot-strike (0.52 ± 0.34 m·s-1) compared to moderate (0.20 ± 0.37 m·s-1) and slow (- 0.08 ± 0.31 m·s-1). The changes to running technique during reactive conditions highlight the need to incorporate decisionmaking in rugby union agility programs. [ABSTRACT FROM AUTHOR]

The article reports on research conducted to determine the impact lower extremity mass manipulation and inertia manipulation had on sprint kinematics. Researchers evaluated eight elite sprinters under normal conditions and after restricted sprint training. They found that lower extremity additional mass training led to a significant reduction in sprint time. They also found that no significant differences were observed across the remaining spatiotemporal variables that they examined.

Background: Recent research highlighted that non-lordotic subtypes are common within an asymptomatic population of young adults. The potential mechanisms responsible for the decreased postural control witnessed in healthy participants exhibiting non-lordotic cervical alignment are unclear.Research Question: Therefore, the aim of this study is to compare and contrast asymptomatic radiographically derived sagittal cervical alignment subtypes with Center of Pressure (CoP) parameters.Methods: In this cross-sectional study strict asymptomatic inclusion criteria were met by 150 of the original 182 volunteers. All radiographs were assessed using a multi-method subtype system with participants classified into lordotic and non-lordotic groups. Participants performed 90s narrow stance trials with their eyes closed whilst standing on both a firm surface (FS) and compliant surface (CS) (3 trials per surface). CoP parameters were recorded from a force platform sampling at 100 Hz. Nonparametric statistical tests were conducted to assess differences between groups for each surface type and to determine differences in CoP parameters between FS and CS types.Results: Significant differences were found between groups on both surfaces for the anterior to posterior range (FS: p = 0.013; CS: p = 0.023), total excursion (FS: p = 0.029; CS: p = 0.005) and mean velocity of total excursion (FS: p = 0.032; CS: p = 0.004).Significance: Our data suggest that sagittal plane cervical alignment is a measure capable of distinguishing between the postural control of asymptomatic lordotic and non-lordotic young adult participants on both surfaces types. Furthermore, decreased postural control is present in asymptomatic participants across all non-lordotic subtypes and is not isolated exclusively to those with forward head posture. Consequently, future research endeavours should investigate the clinical significance of these non-lordotic findings in relation to both the potential for early cervical osseous degeneration and the transitional stages of non-specific pain sufferers from previously asymptomatic young adults. [ABSTRACT FROM AUTHOR]

Background: Static lower extremity alignment (LEA) during normal stance has been used clinically as a tool to determine the presence of known anterior cruciate ligament (ACL) risk factors during dynamic tasks. Previous work investigating the relationship between static LEA during normal stance and risk factors for ACL injury is limited by the use of imprecise methods or because it focuses on knee valgus only and no other potentially important variables. The aim of this investigation was to determine the relationships between static LEA and the corresponding LEA during drop landings., Methods: Forty-one female athletes were recruited for the study (age: 19.8 ± 2.5 years, height: 1.73 ± 0.06 m, mass: 64.03 ± 6.66 kg). Lower limb kinematic data were collected using a 10 camera infrared motion capture system (500 Hz) with retro-reflective markers placed over key anatomical landmarks. This system was linked to two force platforms (1000 Hz) with subsequent three-dimensional kinematic and kinetic data developed using standard software (Visual3D). Following an appropriate warm-up, data collection involved participants standing with their arms partially abducted to record static LEA. This was following by a series of drop landings from a 0.4 m box onto the force platforms. Maximum LEA data during drop landings were then compared with static LEA., Results: Analyses showed that in comparison to static stance, during landings the anterior tilt of the pelvis decreased while hip abduction and knee internal rotation increased. At best, static LEA variables were moderately correlated (r = -0.51 to 0.58) with peak values measured during drop landings. Additionally, regression analysis did not yield any significant predictors of any key peak hip or knee variables measured during drop landings (p = 0.15 to 0.89)., Conclusion: When combined, the poor relationships observed between kinematics during static LEA and LEA during drop landings calls into question the practice of using static measures to predict LEA during even simple landing tasks. These findings suggest static assessments of LEA may have minimal value as an ACL injury screening tool., (© 2023. The Author(s).)

Background: Reconstruction is considered to provide the best opportunity for return to sports (RTS) after anterior cruciate ligament (ACL) rupture. However, recent studies report that <50% of athletes return to preinjury sporting levels and that RTS rates at 1 year after injury are the same for athletes undergoing reconstruction and nonoperative management. Long-term studies are essential to confirm these findings and guide decisions regarding surgery., Purpose: First, to compare long-term sports participation after ACL reconstruction and nonreconstruction and, second, to relate RTS level to strength and stability., Study Design: Cohort study; Level of evidence, 3., Method: Patients with ACL deficiency (n = 101) who were referred for physical therapy at the time of diagnosis were followed long term: 56 were treated surgically 2.5 years (interquartile range [IQR], 1-4) after injury and 45 were treated nonoperatively. At long-term follow-up, the reconstructed group was at 9 years (IQR, 7-11) after injury and aged 33.3 ± 6.2 years (mean ± SD, 70% male; 61% meniscal injury), and the nonreconstructed group was at 11 years (IQR, 7-14) after injury and aged 38.7 ± 8.3 years (67% male; 58% meniscal injury). Measures of objective stability, subjective stability, and quadriceps/hamstring strength were compared between groups using independent-samples t tests. Current RTS level, scored on a 6-point scale, was compared between groups using chi-square tests. Spearman rho correlated RTS with outcome measures., Results: Of the total group of patients, 96% with reconstruction and 93% without continued to play sports. In the reconstructed and nonreconstructed groups, 4% and 7% did not RTS, and 8% and 17% returned to safe sports, respectively: 13% and 12% to running, 20% and 26% to sports involving limited twisting, 12% and 24% to recreational pivoting sports, and 43% and 14% to competitive pivoting sports. The only significant difference was in return to competitive pivoting sports ( P = .003). Five patients with reconstruction ruptured the contralateral ACL, and 1 ruptured his graft. Most patients treated nonoperatively modified their sports participation. Their RTS levels correlated significantly with quadriceps strength ( r = 0.65; P < .001), hamstring strength ( r = 0.721; P < .001), and subjective stability ( r = 0.405; P = .01)., Conclusion: Surgically treated patients returned to competitive pivoting sports at 3 times the rate of those managed nonoperatively, confirming that reconstruction provides the best opportunity for continued participation in competitive pivoting sports. Regardless of grouping, RTS correlated with modifiable factors, including strength and stability. Higher rates of subsequent injuries observed after reconstruction may result from increased participation in competitive pivoting sports.

Objectives: This study examined whether young (15-19 years old) high-performance netball players exhibit different landing mechanics compared to female controls who do not participate in sports requiring frequent landings., Design: Comparative, cross-sectional., Methods: Lower limb kinematics and kinetics from 23 youth high performance female netball players (age: 17.5±1.7 years, height: 1.77±0.06m, mass: 66.5±6.33kg, netball experience: 8.5±2.3 years) were compared to data from 23 females (age: 22.0±3.2 years, height: 1.70±0.05m, mass: 64.4±6.7kg) who were involved in competitive sport, but had minimal experience playing a jump-landing sport. The jump landing task required participants to perform a countermovement jump and grab a netball suspended at 85% of the participant's maximum jump height. On random trials the ball was raised rapidly to 100% maximum jump height as the participant initiated her jump., Results: The netball group landed with significantly less contribution from the knee extensors to total work for the non-preferred leg (P<0.001, ds=1.10) than the inexperienced group. Although no other significant differences were found between groups, there were several small to moderate differences in several of the key biomechanical variables identified as being risk factors for ACL injury or associated with ACL strain., Conclusions: Both groups had similar knee valgus and internal rotation angles and moments, with nearly all participants presenting with relatively poor frontal plane knee control. Overall, results suggest that experience playing a netball may not be enough to develop low-risk landing mechanics., (Copyright © 2019 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Background: Altering the horizontal position of the weight in a backpack will influence the magnitude of the external torque it creates but the effect on posture is unclear., Objective: To use photogrammetry to determine if changes in the horizontal position of a fixed backpack weight affect external measures of craniovertebral posture in 150 asymptomatic young adults., Methods: A backpack was attached to a steel frame with a bar protruding posteriorly. A fixed load (5% body mass) was placed at three distances along the bar -0 m, 0.20 m, and 0.40 m. Sagittal and frontal plane photogrammetry was used to measure the craniovertebral angle (CVA), upper cervical gaze angle (UCGA) and lateral head tilt angle (LHTA). A comparison was made across unloaded (no backpack) and loaded conditions., Results: There was a significant decrease in the CVA between unloaded and loaded conditions. Changes in the UCGA were small and, while significant, may not have practical importance. There were no differences in the LHTA between the conditions., Conclusions: Changes in the horizontal position of a fixed load affect external measures of craniovertebral posture so consideration needs to be given to not only the weight of a backpack but how the weight is positioned within the backpack.

Objectives: This project examined the movement strategies adopted by highly experienced older aged lawn bowlers when performing Draw and Drive deliveries., Design: Cross-sectional., Methods: Twenty five experienced (10.2 ± 7.8 years) older aged lawn bowlers (67.3 ± 7.0 years) who play lawn bowls at least once per week volunteered to participate in this study. Participants performed 10 Draw and Drive deliveries at a target positioned 23 m away while standing on two force platforms (600 Hz), while an infrared motion capture system (200 Hz) recorded phases times and both foot and bowl positioning. Normalised root mean square (NoRMS) analyses was used to assess the bowl path consistency during the delivery phase. Correlation analyses assessed for relationships between age and experience and the spatiotemporal variables, with paired t-tests and effect size (ES) analyses used to examine differences between delivery types., Results: None of the spatiotemporal or NoRMS data achieved more than low correlations with either age or playing experience (R 2  < 0.2). Although bowl release velocities were significantly slower for the Draw 5.25 ± 0.72 m/s than for the Drive deliveries 6.40 ± 0.97 m/s (p < 0.001, ES = 1.96) there were limited changes in any of the spatiotemporal variables. NoRMS data remained largely unchanged between Draw (5.10 ± 1.65) and Drive (5.07 ± 1.49, p = 0.925, ES = 0.02) deliveries., Conclusions: These highly experienced lawn bowlers are adapting their technique to the different task demands of the two delivery types without altering their specific movement strategies., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

This study examined the effect of water immersion on trunk and lower limb kinematics during squat exercises in older participants. A total of 24 active older adults (71.4 ± 5.4 years) performed squats and split squats on land and while partially submerged in water. Inertial sensors (100 Hz) were used to record trunk and lower body kinematics. Water immersion increased the squat depth (squat: p  = .028, d  = 0.63 and split squat: p  = .005, d  = 0.83) and reduced the trunk flexion range (squat: p  = .006, d  = 0.76 and split squat: p  < .001, d  = 1.35) during both exercises. In addition, water immersion increased the hip range of motion during the split squat ( p  = .002, d  = 0.94). Waveform analyses also indicated differences in the timing of the movements. These results showed that water-based exercise generates a different exercise outcome and appears to provide an alternative option for older adults, enabling exercisers to perform these tasks in a manner not possible on land.

Study Design: Non-controlled clinical trial., Objective: To assess the efficacy of a simple home spinal traction device on sagittal cranio-cervical posture and related symptoms., Summary of Background Data: Forward head protraction (FHP) and cranio-cervical malalignment were shown to be consequential in the development adverse musculoskeletal radiographic findings and symptoms in that region., Methods: Participants (n = 13, 18-36-year-old) were drawn from a mildly symptomatic population, all presented with cranio-cervical malalignment and considerable FHP. Participants used a simple home spinal traction device for 12 weeks, 10 min/d. Sagittal cervical radiographs and the SF36 health survey were obtained pre/post intervention and guideline compliance was recorded. Radiographic evaluation included typical measurements of sagittal cranio-cervical alignment and FHP (e.g., atlas plane line, vertical axis line, sagittal cranial angle, absolute rotation angle). Standard paired samples t tests, chi-squared, and effect size analyses were used to assess pre- and post-intervention changes., Results: Each of the key radiographic variables recorded significant moderate to very large positive changes as a result of the intervention. Similarly, Chi-squared analyses indicated that saggital cervical spine configuration tended to become more lordotic (P = 0.007), with four participants shifting from a kyphotic to a lordotic presentation. SF36 health survey data demonstrated mostly significant positive changes throughout all tested domains, and moderate positive changes were recorded across all radiographic cranio-cervical mesured paramenters (e.g., decreased FHP, increased cervical lordosis, and cranial extention). Participants indicated high level of protocol compliance., Conclusion: This study has demonstrated that the unsupervised daily use of a simple home spinal traction device (Thoracic Pillow) proved effective in bringing positive plastic changes to the sagittal cranio-cervical alignment and reduction in symptoms in the tested population during a short intervention period., Level of Evidence: 3.

Background: Recent research highlighted that non-lordotic subtypes are common within an asymptomatic population of young adults. The potential mechanisms responsible for the decreased postural control witnessed in healthy participants exhibiting non-lordotic cervical alignment are unclear., Research Question: Therefore, the aim of this study is to compare and contrast asymptomatic radiographically derived sagittal cervical alignment subtypes with Center of Pressure (CoP) parameters., Methods: In this cross-sectional study strict asymptomatic inclusion criteria were met by 150 of the original 182 volunteers. All radiographs were assessed using a multi-method subtype system with participants classified into lordotic and non-lordotic groups. Participants performed 90s narrow stance trials with their eyes closed whilst standing on both a firm surface (FS) and compliant surface (CS) (3 trials per surface). CoP parameters were recorded from a force platform sampling at 100 Hz. Nonparametric statistical tests were conducted to assess differences between groups for each surface type and to determine differences in CoP parameters between FS and CS types., Results: Significant differences were found between groups on both surfaces for the anterior to posterior range (FS: p = 0.013; CS: p = 0.023), total excursion (FS: p = 0.029; CS: p = 0.005) and mean velocity of total excursion (FS: p = 0.032; CS: p = 0.004)., Significance: Our data suggest that sagittal plane cervical alignment is a measure capable of distinguishing between the postural control of asymptomatic lordotic and non-lordotic young adult participants on both surfaces types. Furthermore, decreased postural control is present in asymptomatic participants across all non-lordotic subtypes and is not isolated exclusively to those with forward head posture. Consequently, future research endeavours should investigate the clinical significance of these non-lordotic findings in relation to both the potential for early cervical osseous degeneration and the transitional stages of non-specific pain sufferers from previously asymptomatic young adults., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: The literature implies that large enthesophytes are exclusive to genetically predisposed individuals and to Spondyloarthropathies sufferers. Accordingly, the aim of this investigation and report was to assess the involvement of genetic predisposition, inflammatory and/or mechanical influences in the development of large enthesophytes in a sample population of teenagers presenting with large enthesophytes emanating from the external occipital protuberance., Methods: Analysis was based on four teenage males (13-16 year-old) possessing 14.5-30.5 mm enthesophytes projecting from the external occipital protuberance. This study included assessment of radiographs, MRI scans, blood-work, history, the SF-36 health survey, and the comparison of these data with the relevant literature to describe the interrelationships between the presence of enlarged external occipital protuberance, forward head protraction, active inflammation and/or genetic factors., Findings: Known genetic markers (e.g. HLA-B27) were not detected by allele-specific primers and both ESR and CRP tests were negative. Additionally, MRI analyses failed to detect active localised inflammation at the external occipital protuberance and surrounding structures. The health survey yielded normal parameters for all participants. All participants displayed significantly large Forward Head Protraction values (>40 mm), and interviews with participants and their parents indicated that concerns related to posture were prevalent since early childhood., Interpretation: This report suggests that mechanical load has an important role in enthesophyte development, irrespective the involvement of inflammatory or genetic factors., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study involved a systematic video analysis of 16 anterior cruciate ligament (ACL) injuries sustained by elite-level netball players during televised games in order to describe the game situation, the movement patterns involved, the player's behaviour, and a potential injury mechanism. Eight of the ACL injuries were classified as "indirect contact" and eight as "non-contact". Two common scenarios were identified. In Scenario A the player was jumping to receive or intercept a pass and whilst competing for the ball experienced a perturbation in the air. As a result the player's landing was unbalanced with loading occurring predominantly on the knee of the injured side. In Scenario B the player was generally in a good position at ground contact, but then noticeably altered the alignment of the trunk before the landing was completed. This involved rotating and laterally flexing the trunk without altering the alignment of the feet. Apparent knee valgus collapse on the knee of the injured side was observed in 3/6 Scenario A cases and 5/6 Scenario B cases. Players may benefit from landing training programmes that incorporate tasks that use a ball and include decision-making components or require players to learn to cope with being unbalanced.

This study assessed the relationships between linear running velocity and change of direction (CoD) ability and how assessing CoD ability over distances ≤5 m influences test reliability. Participants (n = 15) from amateur rugby league teams performed 3 trials of a 20-m sprint test (light gates at 5, 10, and 20 m) and 6 trials of the 5-0-5 agility test. Twelve participants repeated the 5-0-5 test several weeks later. A three-dimensional motion capture system (250 Hz) was used to track the center of mass at 0.3, 0.5, and 1.0 m either side of the turn and identify specific CoD phase times. Pearson's correlations showed strong significant relationships between the 5-0-5 time and 5-m (r = 0.89, p < 0.001), 10-m (r = 0.91, p < 0.001), and 20-m sprint times (r = 0.93, p < 0.001). However, the strength of these relationships decreased (r < 0.65, p > 0.05) when CoD ability was measured over distances less than 0.5 m. Analysis of coefficient of variation (CV%) data indicated that the 5-0-5 test had high intratest (CV% = 2.8) and intertest reliability (CV% = 1.3), with these data decreasing for distances less than 1 m (CV% = 3.5-6.9). Specific movement phase times were the least reliable measures of CoD ability (CV% = 4.7-53.6). Results suggest a bias between high-speed linear running ability and 5-0-5 time. However, an effective compromise can be found between test reliability and the external validity by assessing CoD ability over 1 m. Findings indicate that the current practice of assessing CoD ability over large distances in questionable.

This project assessed dynamic balance and stability in aged lawn bowlers during the delivery stride. Participants were divided into two groups: aged 65 years or less (n = 14) and aged over 65 years (n = 16). Standard balance-based center of pressure (CoP) and ground reaction force variables were recorded and a Dynamic Postural Stability Index (DPSI) was used for calculating during ten deliveries. None of the balance variables correlated significantly with age although years of bowling experience correlated with DPSI scores (r = -.42, P = .019). The over 65 group had significantly greater variance in the mediolateral CoP movements, with no other significant differences in balance or postural stability variables between groups. Analysis of covariance indicated that the DPSI data were influenced significantly by bowling experience regardless of age group. It was concluded that in older aged lawn bowlers, playing experience rather than age is a key determinant of balance control during the lawn bowls delivery action.

This study used both an instantaneous net drag force profile and a symmetry timing to evaluate the effect of the breathing action on stroke coordination. Twenty elite swimmers completed a total of six randomised front-crawl towing trials: (i) three breathing trials and (ii) three non-breathing trials. The net drag force was measured using an assisted towing device mounted upon a Kistler force platform, and this equipment towed the swimmer at a constant speed. The net drag force profile was used to create a stroke symmetry index for each swimming trial. Analysis using the symmetry indices identified that the majority of participants demonstrated an asymmetrical instantaneous net drag force stroke profile in both the breathing and non-breathing conditions, despite no significant differences in the time from finger-tip entry to finger-tip exit. Within the breathing condition, the faster swimmers compared to the slower swimmers demonstrated a lesser percentage of overlap between stroke phases on their breathing stroke side. During the non-breathing condition, the faster participants compared to the slower swimmers recorded a reduction in the percentage of overlap between stroke phases and less duration in the underwater stroke on their breathing stroke side. This study identified that the majority of participants demonstrated an asymmetrical net drag force profile within both conditions; however, asymmetry was less prevalent when examining with only the timing symmetry index.

Putting proficiency is a key determinant of golfing success and yet minimal biomechanical research has been published on this important skill. Little is known about the motion and coordination of the pelvis and trunk during the putting motion. The purpose of this study was to present detailed three-dimensional (3D) kinematic profiles of the pelvis and trunk during the putting motion, and to determine if differences in kinematics exist between proficient and non-proficient golfers. A 3D analysis (100 Hz) was conducted on 10 single figure handicap golfers using a six-camera motion capture system. Participants completed 18 putts (2 m) towards a cup in an indoor facility and were subsequently divided into two groups based on putting proficiency (Proficient: >79%; Non-proficient: <79%). Variables assessed were the linear movements of the centre of mass (COM) and head, and the angular movements of the pelvis and trunk. Effect size statistics showed that the Proficient putters tended to move predominantly in the frontal plane (towards the target), while the non-proficient putters moved more sagittally. In addition, the Non-proficient putters recorded greater movement variability. The implications of this study suggest that putting proficiency is enhanced when the COM moves towards the target.