Trunk Lateral Flexion Research Articles

EFFECT OF BODY-BORNE LOAD ON LATERAL TRUNK FLEXION AND ITS RELATION TO KNEE ABDUCTION BIOMECHANICS DURING A SINGLE-LEG CUT

Body-borne load reportedly increases incidence of military-related knee injury by altering trunk and lower limb biomechanics. This investigation determined whether body-borne load impacts lateral trunk flexion during a single-leg cut, and whether greater lateral trunk flexion exaggerates knee abduction biomechanics. Thirty-six participants had trunk and knee biomechanics quantified during a single-leg cut with four body-borne loads (20, 25, 30 and 35[Formula: see text]kg). To evaluate the impact of load on lateral trunk flexion and its relation with knee abduction biomechanics, peak stance lateral trunk flexion was submitted to a linear mixed model with load (20, 25, 30, and 35[Formula: see text]kg) and sex (male, female) as fixed effects, and dominant limb peak stance knee abduction joint angle and moment considered as covariates. During the cut, there was a significant sex by load interaction for peak stance lateral trunk flexion ([Formula: see text]), and peak stance lateral trunk flexion angle exhibited a significant association with peak stance knee abduction angle ([Formula: see text]) and moment ([Formula: see text]). Adopting lateral trunk flexion during loaded single-leg cuts may increase knee biomechanics related to ACL injury, but adding load only decreased lateral trunk flexion for female participants and did not further exaggerate knee abduction biomechanics.

Effect of isolated hip abductor fatigue on single-leg landing mechanics and simulated ACL loading

BackgroundAltered movement biomechanics are a risk factor for ACL injury. While hip abductor weakness has been shown to negatively impact landing biomechanics, the role of this musculature and injury risk is not clear. The aim of this musculoskeletal simulation study was to determine the effect of hip abductor fatigue-induced weakness on ACL loading, force production of lower extremity muscles, and lower extremity biomechanics during single-leg landing. MethodsBiomechanical data from ten healthy adults were collected before and after a fatigue protocol and used to derive subject-specific estimates of muscle forces and ACL loading using a 5-degree of freedom (DOF) model. ResultsThere were no significant differences in knee joint angles and ACL loading between pre and post-fatigue. However, there were significant differences, due to fatigue, in lateral trunk flexion angle, total excursion of trunk, muscle forces, and joint moments. ConclusionAltered landing mechanics, due to hip abductor fatigue-induced weakness, may be associated with increased risk of ACL injury during single-leg landings. Clinical assessment or screening of ACL injury risk will benefit from subject-specific musculoskeletal models during dynamic movements. Future study considering the type of the fatigue protocols, cognitive loads, and various tasks is needed to further identify the effect of hip abductor weakness on lower extremity landing biomechanics.

Measurements of Lower-limb Isometric Single-joint Maximal Voluntary Torque and Rate of Torque Development Capacity Offer Limited Insight into Vertical Jumping Performance

ABSTRACT We examined the relationships between heights of different vertical jumps and isometric single-joint strength characteristics of ankle, knee, hip, and trunk joints in young male soccer players (n = 117). The highest peak torque and rate of torque development (RTD) outcomes were in low to moderate correlation with jump heights (r = 0.25–0.50). The correlations were generally higher for bilateral than unilateral jumps. Linear regression models accounted for 33–35% and 24.5 of the variance in bilateral and unilateral jump height, respectively. Hip extension peak torque, ankle RTD and trunk lateral flexion peak torque were most consistently included in the regression models. Our results suggest the that single-joint isometric testing does not seem to be useful to detect weaknesses related to vertical jump performance. The relative importance of individual lower limb joints for vertical jumping seems comparable. Trunk strength should not be neglected as the determinant of jumping performance.

The influence of rotational movement exercise on the abdominal muscle thickness and trunk mobility – Randomized control trial

BackgroundTrunk rotations are important functional movements which form the foundations of human motion pattern, especially in the functions of walking and running. They prevent the functional impairments and structural lesions resulting from axial overloading in static positions such as sitting. ObjectivesThe aim of the study was to assess the influence of rotational movement training exercises on the abdominal muscle thickness and spinal mobility range. Study design: Randomized controlled trial. MethodsThe study involved 73 individuals aged 18–45. The subjects were randomly divided into two groups. The study group (TG) comprised 40 people who performed rotational movement exercises over the period of 4 weeks (16 training sessions). In the control group (CG) the training was not applied. Changes in the thickness of selected abdominal muscles on ultrasound imaging were evaluated, as well as trunk mobility, based on the trunk lateral flexion test. ResultsThe analysis of the obtained data has demonstrated a statistically significant increase in the thickness of the abdominal internal (IO) (p < 0.05) and external oblique muscles (EO) (p < 0.001) in the study group (TG) between measurements I and II, and measurements I and III. A similar increase in the thickness was found in the summation measurement of TrA + IO + EO. Bilateral increase in the trunk lateral flexion range in the frontal plane has also been noted. ConclusionsRotational movement training of the trunk leads to an increase in the thickness of the abdominal oblique muscles. Rotational movement exercise training increases trunk mobility in the frontal plane.

Shoulder function after constraint-induced movement therapy assessed with 3D kinematics and clinical and patient reported outcomes: A prospective cohort study

IntroductionWe hypothesised that reduced shoulder function post stroke improves during constraint-induced movement therapy and that improvement in scapula upward rotation measured with three-dimensional kinematics is associated with improvements in clinical and patient reported outcomes. MethodsThirty-seven patients were tested pre and post constraint-induced movement therapy and again at three-month follow-up. Kinematic outcome measures – with scapula upward rotation as the primary outcome – during tasks 5 (ReachLow) and 6 (ReachHigh) from the Wolf Motor Function Test were included together with clinical and patient reported outcomes. Changes in outcome measures were analysed with linear mixed models and logistic regression analysis. FindingsScapula upward rotation was reduced from 16.2° pre intervention through 15.9° post intervention to 15.6° at three-month follow-up during ReachHigh. Statistically significant reductions of <2° were also found for shoulder flexion during ReachLow and trunk lateral flexion during ReachHigh. The clinical and patient reported outcomes showed improvements post constraint-induced movement therapy, and at follow-up, the outcomes resembled post values. InterpretationThe minimal improvements in selected 3D kinematic measures of upper extremity movements did not reflect any clinically meaningful changes. Therefore, the clinical and patient reported improvements could not be related to restitution of shoulder function.

Assessment of trunk lateral flexion range of movement using a novel method in first class cricket players.

Lateral flexion range of movement (LF ROM) is used to assess and monitor recovery of side strain injury in athletes. This study established a reliable and pragmatic measure of LF ROM and investigated the stability of the measure over time in athletes. 1) Cross-sectional reliability study and 2) Cohort longitudinal study. Elite cricket teams in COUNTRY-AAA and COUNTRY-BBB Participants: Cricket players Methods: 1) The intra- and inter-rater reliability of two methods of measuring LF ROM were assessed (distance to the floor or distance to fibular head). Ten healthy first-class cricket bowlers were tested by three experienced physiotherapists. Intra-class correlations (2,1) were calculated for absolute agreement for all 3 testers. 2) Professional cricket fast bowlers were recruited from COUNTRY-AAA and COUNTRY-BBB domestic and international competitions. Lateral flexion range of movement was measured monthly during the pre- and competitive season. A one-way repeated measures analysis of variance was performed to identify difference within the pre-season, within the competitive season, and between competitive seasons. Lateral flexion range of movement towards and away from the bowling arm. Both methods had good intra- and inter-test reliability (ICC>0.84). As LF ROM to the floor was easier for clinicians it was used for the longitudinal study. Lateral flexion range of movement did not significantly alter throughout the pre- and competitive season or between seasons (p>0.05). This new method of describing LF ROM demonstrates good intra- and inter-rater reliability and stability over time and can be used as an outcome measure in side-strain injury.

Single-Leg Squat Compensations Are Associated With Softball Pitching Pathomechanics in Adolescent Softball Pitchers.

Background:A lack of lumbopelvic-hip complex (LPHC) stability is often associated with altered pitching mechanics, thus increasing pain and injury susceptibility. The single-leg squat (SLS) is a simple diagnostic tool used to examine LPHC stability.Purpose:To examine the relationship between trunk compensatory kinematics during the SLS and kinematics at foot contact during the windmill pitch.Study Design:Descriptive laboratory study.Methods:Participants included 55 youth and high school softball pitchers (mean age, 12.6 ± 2.2 years; height, 160.0 ± 11.0 cm; weight, 60.8 ± 15.5 kg). Kinematic data were collected at 100 Hz using an electromagnetic tracking device. Participants were asked to complete an SLS on each leg, then throw 3 fastballs at maximal effort. Values of trunk flexion, trunk lateral flexion, and trunk rotation at peak depth of the SLS were used as the dependent variables in 3 separate backward-elimination regression analyses. Independent variables examined at foot contact of the pitch were as follows: trunk flexion, trunk lateral flexion, trunk rotation, center of mass, stride length, and stride knee valgus.Results:The SLS trunk rotation regression (F(1,56) = 4.980, P = .030) revealed that trunk flexion predicted SLS trunk rotation (SE = 0.068, t = 2.232, P = .030) and explained approximately 7% of the variance in SLS trunk rotation (R 2 = 0.083, adjusted R 2 = 0.066). The SLS trunk flexion regression (F(1,56) = 5.755, P = 0.020) revealed that stride knee valgus significantly predicted SLS trunk flexion (SE = 0.256, t = 2.399, P = .020) and explained approximately 8% of variance in SLS trunk flexion (R 2 = 0.095, adjusted R 2 = 0.078).Conclusion:Additional trunk rotation and trunk flexion at peak depth of the SLS showed increased knee valgus and trunk flexion at foot contact of the pitch, both of which indicate poor LPHC stability during the softball pitch and may increase the potential for injury.Clinical Relevance:Players and coaches should implement SLS analyses to determine their players’ risk for injury and compensation due to poor core stability.

Differences in trunk range of motion for various flexibility protocol types, particularly in quarterbacks wearing rib protectors

Summary Background It is unclear how rib protectors may affect trunk mobility in American football players. The purposes of the study were: 1) to determine which flexibility protocol (active-assisted, maximal-speed, self-selected) exhibits the highest range of motion for trunk lateral flexion and axial rotation and 2) to determine the effect of rib protectors (hard-rib and soft-rib protectors and control: compression shirt only) on trunk range of motion. Methods Eleven male participants with competitive quarterback experience were recruited. Participants were instructed to rotate the trunk in the lateral flexion and axial rotation directions during each flexibility protocol and rib protector condition. The lower-thoracic range of motion were measured. Results Two-way repeated measures ANOVA (flexibility protocol by rib protector) demonstrated significant main effect of flexibility protocol for lateral flexion, but not axial rotation. The range of motion during self-selected protocol was significantly greater than maximal-speed protocol by approximately 7° (p = .009). Conclusions Self-selected and maximal-speed protocol produced the highest lateral flexion and axial rotation range of motion, respectively, and can be used to test the influence of rib protectors and potentially other sports equipment on thoraco-lumbar range of motion. Additionally, rib protectors likely do not affect trunk range of motion needed to throw long-distance passes or other movements as performed by football quarterbacks.

Kinematic Differences Exist Between the Fastball, Changeup, Curveball, and Dropball Pitch Types in Collegiate Softball Pitchers

Background: A majority of softball literature focuses on the mechanics associated with pain and injury within a single pitch type per study; however, the generalizability of these findings is unknown since a kinematic comparison has yet to be performed between pitch types. Understanding kinematic differences between pitch types can be used to identify risk factors for injury, improve safety guidelines, and improve performance by linking specific mechanics with desired pitch outcomes. Hypothesis/Purpose: The purpose of this study was to compare kinematics between the fastball, changeup, curveball, and dropball pitch types in collegiate softball pitchers. It was hypothesized that there would be significant kinematic differences between pitch types. Study Design: Descriptive laboratory study. Methods: A total of 28 female collegiate softball pitchers pitched 3 trials of each pitch type to a catcher at regulation distance. Pitch speed, stride length, trunk extension, trunk rotation, trunk lateral flexion, elbow flexion, and center of mass for each trial were calculated using an electromagnetic motion capture system and were averaged for analysis. A 1-way analysis of variance (ANOVA) was used to investigate pitch speed differences between the 4 pitch types. A 4 (pitch type) × 5 (event) within-athlete multivariate ANOVA was also used to determine kinematic differences. Results: The results revealed a significant difference in pitch speed between pitch types; a pitch type main effect for trunk extension, trunk rotation, trunk lateral flexion, and center of mass; and an event main effect for all variables except stride length. The results also revealed a pitch type by event interaction for trunk flexion, trunk lateral flexion, and center of mass. Specifically, the dropball type had less trunk extension than the fastball at all pitching events. Similarly, the curveball type had a more posteriorly shifted center of mass than the dropball at the last 3 pitching events of foot contact, ball release and follow-through. Conclusion: Significant kinematic differences exist between pitch types, but these differences may be necessary to execute desired pitch outcomes. Clinical Relevance: This is the first study to analyze kinematic differences between pitch types in softball pitchers. Understanding the effects of different pitch types on kinematic parameters may enhance injury prevention and performance strategies for softball pitchers.

Postural Control Performance on the Functional Reach Test: Validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) Criteria

ObjectiveEvaluate the validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) clinical criteria for the Functional Reach Test (FRT) forward and lateral with laboratory measures of postural control in children with cerebral palsy (CP). DesignPsychometric study of face, concurrent, and content validity. SettingClinical laboratory. ParticipantsChildren (N=58) aged 7-18 years (ambulant CP n=17, typically developing [TD] n=41). InterventionNot applicable. Main Outcome MeasuresStability limits in standing were assessed using the Kids-BESTest items for FRT forwards (FRTFORWARD), FRT lateral preferred (FRTLATERAL(P)), and FRT lateral nonpreferred (FRTLATERAL(NP)). Force platforms and kinematic markers were used to collect information on center of pressure (CoP) and joint movement during reach. Analyses included face validity (Kids-BESTest scores compared between CP and TD groups), concurrent validity (agreement between Kids-BESTest scores and digitally derived scores), and content validity (relations between Kids-BESTest scores with kinematic and CoP data). ResultsFace validity of Kids-BESTest criteria was demonstrated with lower scores for CP compared to TD groups for FRTFORWARD (P<.001) and FRTLATERAL(NP) (P=.03) and equal scores for FRTLATERAL(P) (P=.12). For concurrent validity, agreement between Kids-BESTest scores and digitally derived scores was good to excellent for FRTLATERAL(both P/NP) (88%-100%) and good for FRTFORWARD (86%-88%) for both groups. For content validity, the CP group Kids-BESTest scores were correlated with CoP-RangeFORWARD during FRTFORWARD (ρ=0.68) and CoP-RangeLATERAL during FRTLATERAL(NP) (ρ=0.57). For kinematic data, correlations were moderate-high between Kids-BESTest scores and range of hip flexion (ρ=0.51) and ankle plantar flexion (ρ=0.75) during FRTFORWARD, and trunk lateral flexion (ρ=0.66) during FRTLATERAL(NP). ConclusionThe FRTFORWARD demonstrated face, concurrent, and content validity. The FRTLATERAL(P/NP) demonstrated concurrent validity, but partial face and content validity. To improve validity of Kids-BESTest FRT criteria, additional descriptors have been added under the scoring criteria to enable clinicians to quantify observed reach strategies.

Relationship between Sitting Pressure Deviation and Trunk Lateral Flexion

Relationship between Sitting Pressure Deviation and Trunk Lateral Flexion

Dynamic Knee Valgus in Single-Leg Movement Tasks. Potentially Modifiable Factors and Exercise Training Options. A Literature Review.

Dynamic knee valgus (DKV) as an incorrect movement pattern is recognized as a risk factor for lower limb injuries. Therefore, it is important to find the reasons behind this movement to select effective preventive procedures. There is a limited number of publications focusing on specific tasks, separating the double-leg from the single-leg tasks. Test patterns commonly used for DKV assessment, such as single-leg squat (SLS) or single leg landings (SLL), may show different results. The current review presents the modifiable factors of knee valgus in squat and landing single-leg tests in healthy people, as well as exercise training options. The authors used the available literature from PubMed, Scopus, PEDro and clinicaltrials.gov databases, and reviewed physiotherapy journals and books. For the purpose of the review, studies were searched for using 2D or 3D motion analysis methods only in the SLL and SLS tasks among healthy active people. Strengthening and activating gluteal muscles, improving trunk lateral flexion strength, increasing ROM dorsiflexion ankle and midfoot mobility should be taken into account when planning training programs aimed at reducing DKV occurring in SLS. In addition, knee valgus during SLL may occur due to decreased hip abductors, extensors, external rotators strength and higher midfoot mobility. Evidence from several studies supports the addition of biofeedback training exercises to reduce the angles of DKV.

Change of Direction Performance Is Influenced by Asymmetries in Jumping Ability and Hip and Trunk Strength in Elite Basketball Players

Change of direction (COD) ability is essential for sport performance in high level team sports such as basketball, however, the influence of asymmetries on COD ability is relatively unknown. Forty-three junior and senior level elite basketball players performed isometric hip and trunk strength testing, passive hip and trunk range of motion testing, and unilateral horizontal and vertical jumps, as well as the T-test to measure COD performance. Mean asymmetry values ranged from 0.76% for functional leg length up to 40.35% for rate of torque development during hip flexion. A six-variable regression model explained 48% (R2 = 0.48; p &lt; 0.001) of variation in COD performance. The model included left hip internal/external rotation strength ratio, and inter-limb asymmetries in hip abduction rate of torque development, hip flexion range of motion, functional leg length, single leg triple jump distance, and peak torque during trunk lateral flexion. Results suggest that the magnitude of asymmetries is dependent of task and parameter, and using universal asymmetry thresholds, such as &lt;10 %, is not optimal. The regression model showed the relationship between asymmetries and COD performance. None of tests were sufficient to explain a complex variable like COD performance.

Test-retest Reliability of a Novel Lateral Trunk Flexion Test in

Test-retest Reliability of a Novel Lateral Trunk Flexion Test in

The link between lateral trunk flexion in Parkinson’s disease and vestibular dysfunction: a clinical study

Introduction Lateral trunk flexion (LTF) is a common postural deformity in Parkinson’s disease (PD). Postural control is known to depend on visual, vestibular, and somatosensory information. Objectives This study aimed to investigate the relationship between vestibular dysfunction and postural abnormalities in PD patients with LTF. Methods We enrolled a total of 19 PD patients with LTF (PD-LTF+) and 19 age- and sex-matched PD patients without LTF (PD-LTF-). All patients underwent vestibular tests, including spontaneous nystagmus, gaze-evoked nystagmus, ocular movements, optokinetic eye test, fast positioning maneuvers, and the bithermal caloric test. Results Most of the PD-LTF + patients had abnormal vestibular function (11/19), while there were fewer vestibular function injuries in the control group (3/19). In PD-LTF + group, there were 5 patients (5/11, 45.5%) of peripheral vestibular dysfunction, 2 patients (2/11, 18.2%) of central vestibular damage, and 4 patients (4/11, 36.4%) of mixed injuries. The peripheral vestibular deficiencies could be either bilateral (4/9, 44.4%) or unilateral (5/9, 55.6%). The unilateral vestibular dysfunction was ipsilateral to the leaning side in 2 patients and contralateral to the leaning side in the other 3 patients. Conclusion Vestibular dysfunction may be an independent risk factor for LTF in PD patients.

Influence of Anticipation and Motor-Motor Task Performance on Cutting Biomechanics in Healthy Men

Biomechanical analyses of cutting tasks have demonstrated kinematic differences associated with the noncontact knee-injury risk when the movement direction is unanticipated. Motor-motor dual tasks occur within dynamic environments and change the demand for attentional resources needed to complete athletic maneuvers, which may contribute to injury risk. To investigate the influence of anticipation and motor-motor task performance on cutting biomechanics. Cross-sectional study. Laboratory. A total of 32 healthy, recreationally active men (age = 23.1 ± 3.6 years, height = 180.0 ± 7.0 cm, mass = 81.3 ± 17.3 kg) who self-reported regular participation in cutting sports. Participants performed a 45° side-step cut on the dominant limb in a random order of conditions: anticipation (anticipated, unanticipated) and task (no ball throw, ball fake, ball throw). Triplanar trunk, hip, and knee angles were assessed throughout the stance phase using 3-dimensional motion capture. Data were analyzed using a time series of means calculated from initial contact to toe-off (0%-100%) with 90% confidence intervals. Mean differences between conditions were identified as regions of nonoverlapping confidence intervals, and those that occurred during the region of peak vertical ground reaction force (0%-25%) are presented. Regardless of anticipation, attending to a ball (ball throw) resulted in more trunk extension (range = 2.9°-3.7°) and less lateral trunk flexion toward the cutting direction (range = 5.2°-5.9°). Planning to attend to a ball (ball fake) resulted in less lateral trunk flexion toward the cutting direction (4.7°). During unanticipated cutting, more trunk rotation away from the cutting direction was observed when attending to a ball (range = 5.3°-7.1°). The interaction of anticipation and task had a similar influence on sagittal- and frontal-plane trunk position. Motor-motor task performance and its interaction with anticipation induced an upright, neutral trunk position during side-step cutting, which has been associated with the risk for noncontact knee injury. Promoting task complexity during rehabilitation and injury-prevention programs may better prepare individuals to succeed when performing high-risk athletic maneuvers.

Modifying bowling kinematics in cricket pace bowlers with exercise-based injury prevention: A cluster-randomised controlled trial

ObjectivesUndesirable bowling kinematics can increase the risk of low back injury. This study investigated if an exercise-based injury prevention program (IPP) could modify bowling kinematics in community-level adolescent pace bowlers. DesignCluster-randomised controlled trial. MethodsPace bowlers from eight cricket organisations were cluster-randomised into an intervention or control group. At baseline and follow-up sessions biomechanical bowling data were collected. Between sessions, the intervention group completed an eight-week IPP while the control continued their normal cricket activity. Treatment effects (95% CI) were estimated with linear mixed models. ResultsThere were significant treatment effects favouring the intervention group for shoulder counter-rotation (−3.8°; −7.2° to −0.3°) and lateral trunk flexion relative to the pelvis (−2.2°; −4.0° to −0.5°). Shoulder counter-rotation also increased in the control group by 2.2° (Cohen’s d=0.22). There were no effects of the intervention on: lateral trunk flexion at front foot contact (FFC) (1.2°; −2.5° to 4.8°), lateral trunk flexion at ball release (BR) (−0.5°; −3.0° to 2.0°), pelvis rotation at FFC (0.9°; −4.0° to 2.2°), pelvis rotation at BR (−1.1°; −5.7° to 3.6°), front hip angle at FFC (1.6°; −3.6° to 6.7°), front hip angle at BR (−1.6°; −5.0° to 1.9°), front knee angle at FFC (−1.1°; −4.5° to 2.3°), front knee angle at BR (1.7°; −5.6° to 9.1°), or ball velocity (1.1kmh−1; −7.5kmh−1 to 9.7kmh−1). ConclusionsThe IPP maintained shoulder counter-rotation and lateral trunk flexion relative to the pelvis in the intervention group and this could attenuate injury risk. No treatment effects were observed for lower-limb kinematics.

Arm abduction angle at ball release influences shoulder forces and torques during the windmill softball pitch

Objectives:Shoulder pain and ligamentous injury is a common complaint among fast pitch softball pitchers. In addition to extreme shoulder joint motion during pitch delivery, sudden deceleration immediately after ball release places increased stress across the shoulder joint. Some pitchers release the ball with the throwing arm tucked close to the trunk, while others let the arm float outwards in a more abducted position. The position of the arm at ball release (BR) may be key to the mechanism of shoulder pain. Previous work demonstrated that during the change up pitch, softball pitchers with upper extremity pain demonstrated greater shoulder abduction at stride and less trunk lateral flexion at BR compared to athletes without pain (Oliver et al 2018). The purpose of this study was to test the hypothesis that placement of the arm closer to the trunk (shoulder adduction) at ball release will produce less shoulder stress during fastball windmill pitches.Methods:Twenty-six female fast pitch softball pitchers with a mean age of 18 +/- 6 y, including 16 high school, 7 collegiate, and 3 professional athletes, underwent 3D biomechanical pitch analyses using 20 Vicon high-speed motion capture cameras (240 hz). All pitchers threw the standard 13.11 m mound-to-plate distance at a strike zone target while a radar gun collected pitch speeds. The fastest, most accurate fastball pitches for each subject were selected for analyses (average of 5 pitches per subject). A total of 103 pitches were used to calculate: shoulder abduction angle and shoulder compression force during the BR phase (10 frames surrounding BR) and peak shoulder torques. Pearson correlations were performed to determine the relationship of shoulder frontal plane (adduction/abduction) angle during the ball release phase to these biomechanical measures.Results:The smallest abduction shoulder angle reached during the BR phase (avg: 14.06 +/- 6.71 degrees) demonstrated a significant positive correlation with shoulder compression force, p=0.008 and with peak flexion torque, p< 0.001 (Table 1). This shoulder abduction angle during the BR phase demonstrated negative correlations with peak shoulder adduction torque, p<0.001 and shoulder internal rotation torque, p< 0.001.Conclusion:These initial findings support the hypothesis that pitchers who release the ball with their arm close to their trunk demonstrate lower shoulder compression forces and shoulder flexion torques than those with a more abducted arm position. Future studies are needed to explore the interplay of pitching technique mechanics, shoulder joint stresses, and injury history to inform pitching instruction and injury prevention efforts.Table 1.The relationship between shoulder frontal plane angle during ball release with shoulder compression force and torquesMeasureAverage SDRPBall release phase peak shoulder compression force7.791.53 BW0.258*0.008Peak shoulder internal rotation torque-27.4528.65 Nm-0.377*P < 0.001Peak shoulder adduction torque-47.8649.59 Nm-0.479*P < 0.001Peak shoulder flexion torque60.7946.01 Nm0.530*P < 0.001*Established level of significance p<0.05

Relationship between trunk control, core muscle strength and balance confidence in community-dwelling patients with chronic stroke

ABSTRACT Background and objective Impaired trunk control and core muscle weakness affect balance capacity after stroke, but confirmatory literature is lacking. The objective was to examine the relationship between trunk control, core muscle strength and self-confidence on balance efficacy in community-dwelling chronic stroke survivors and to identify trunk performance measures for determining balance confidence. Methods Patients with a median post-stroke duration of 12 (IQR 7–18) months and independent walking ability participated in this cross-sectional study. Trunk control, core muscle strength and balance confidence were measured using trunk impairment scale 2.0 (TIS 2.0), handheld dynamometer and activity-specific balance confidence scale, respectively. Correlation among TIS 2.0, core muscle strength and balance confidence were tested by Pearson’s correlation coefficient. Stepwise multivariate linear regression analysis was conducted to examine the most important trunk performance variables determining balance confidence. Results Of 177 study participants, the median (IQR) score for TIS 2.0 was 10 (7–12) out of 16 and for balance confidence 41 (27–61) out of 100. Trunk control was highly correlated to overall core muscles strength (r = 0.61–0.70, p <.001) and balance confidence (r = 0.66, p <.001). The major trunk determinants of balance confidence were TIS 2.0 total score (partial R2 = 0.433) and dynamic sitting balance, i.e. trunk lateral flexion (partial R2 = 0.376) in chronic stroke. Conclusion A significant and strong positive association exists among trunk control, core muscles strength and balance confidence in community-dwelling patients with chronic stroke, warranting further investigation of the effect of targeted trunk rehabilitation strategies on functional balance.

Efficacy of Osteopathic Manipulative Treatment on postural control in Parkinsonian patients with Pisa syndrome: A pilot randomized placebo-controlled trial.

Pisa syndrome (PS) is a clinical condition frequently associated with Parkinson's disease (PD). It is characterized by a trunk lateral flexion higher than 10 degrees and reversible when lying. One pathophysiological hypothesis is the altered verticality perception, due to a somatosensory impairment. Osteopathic Manipulative Treatment (OMT) manages fascial-system alterations, linked to somatic dysfunctions. Fascial system showed to be implicated in proprioceptive sensibility. The aim of the study was to assess OMT efficacy on postural control in PD-PS patients by stabilometry. In this single-blinded trial we studied 24 PD-PS patients, 12 of whom were randomly assigned to receive a multidisciplinary physical therapy protocol (MIRT) and sham OMT, while the other 12 received four OMT plus MIRT, for one month. The primary endpoint was the eye closed sway area assessment after the intervention. Evaluation of trunk lateral flexion (TLF) with DIERS formetrics was also performed. At one month, the sway area of the OMT group significantly decreased compared to placebo (mean delta OMT - 326.00±491.24 mm2, p = 0.01). In the experimental group TLF showed a mean inclination reduction of 3.33 degrees after treatment (p = 0.044, mean d = 0.54). Moreover, a significant positive association between delta ECSA and delta TLF was observed (p = 0.04, r = 0.46). Among PD-PS patients, MIRT plus OMT showed preliminary evidence of postural control and TLF improvement, compared to the control group.