Hip Flexion Research Articles

Effect of weight around ankle on decreasing hip flexion excursion during gait in children with diplegia

Effect of weight around ankle on decreasing hip flexion excursion during gait in children with diplegia

Effects of different slopes on hip and ankle biomechanics of replaced and non-replaced limbs of patients with total knee arthroplasty during incline ramp walking

Although knee biomechanics has been examined, hip and ankle biomechanics in incline ramp walking has not been explored for patients with total knee arthroplasty (TKA). The purpose of this study was to investigate the hip and ankle joint kinematic and kinetic biomechanics of different incline slopes for replaced limbs and non-replaced limbs in individuals with TKA compared to healthy controls. Twenty-five patients with TKR and ten healthy controls performed walking trials on four slope conditions of level (0°), 5°, 10° and 15° on a customized instrumented ramp system. A 3x4 (limb x slope) repeated analysis of variance was used to evaluate selected variables. The results showed a greater peak ankle dorsiflexion angle in the replaced limbs compared to healthy limbs. No significant interactions or limb main effect for other ankle and hip variables. The peak dorsiflexion angle, eversion angle and dorsiflexion moment were progressively higher in each comparison from level to 15°. The peak plantarflexion moment was also increased with each increase of slopes. Both the replaced and non-replaced limbs of patients with TKA had lower hip flexion moments than the healthy control limbs. Hip angle at contact and hip extension range of motion increased with each increase of slopes. Peak hip loading-response internal extension moment increased with each increase in slope and peak hip push-off internal flexion moment decreased with each increase of slope. Our results showed increased dorsiflexion in replaced limbs but no other compensations of hip and ankle joints of replaced limbs compared to non-replaced limbs and their healthy controls during incline walking, providing further support of using incline walking in rehabilitation for patients with TKA.

Behavioral and cortical dynamics underlying superior accuracy in short-distance passes

Improved pass accuracy is a prominent determinant of success in football. It demands an effective interaction of complex behavioral and cortical dynamics. Exploring differences in the ability to sustain an accurate pass behavior in a stable setting and the associated cortical dynamics at different expertise levels may provide an insight into skilled strategies contributing to superior accuracy in football. The aim of this study is to compare trial-to-trial variability of pass biomechanics and the corresponding cortical dynamics during short-distance passes between novices and experienced football players. Thirty participants (15 novices, 15 football players) performed 90 short-distance passes. The intertrial variability of pass biomechanics (foot acceleration, range of hip flexion, knee flexion and foot rotation) was assessed by means of multiscale entropy. The task-related cortical dynamics were analyzed via source-derived event-related spectral perturbations. Experienced players demonstrated higher accuracy and overall lower entropy values across multiple time scales which was significant for hip flexion. The electroencephalography data revealed group differences in parieto-occipital alpha desynchronization and frontal theta synchronization in successive phases of passes. The current findings suggest that experienced football players may show a skilled ability to recruit and retain pass biomechanics promoting higher accuracy, whereas novices may show an explorative behavior with higher spatial variability. This difference may be associated with distinctive visuospatial and attentional strategies acquired with expertise in football. Our study provides an insight into expertise-specific behavioral and cortical dynamics of superior accuracy in football and a basis for its prospective investigation in enriched contexts.

Fatigue Test Method to Evaluate the 50 Year Durability of Venous Stents

Iliofemoral venous obstructive disease can result in significant, potentially debilitating symptoms that can negatively affect quality of life. Unlike arterial disease, patients with deep venous disease have a significantly lower median age, therefore the need for long term stent patency becomes a matter of decades rather than years. Furthermore, iliofemoral lesions frequently require stent placement across the inguinal ligament. Such stents are subject to dynamic stress from leg movement and associated concerns for device fatigue, resulting in stent fracture. The aim of this study was to describe an invitro 50 year stent fatigue test method designed to assess durability against dynamic stress induced device fracture. Through literature review, cadaver studies, and computer modelling, the most challenging loading was confirmed to be hip flexion across the inguinal ligament. This occurs when the patient adjusts between a seated and standing position. Sit to stand hip flexion at the inguinal ligament was effectively simulated on the bench in this invitro experimental study. When tested under challenge parameters, hip flexion was reliably found to cause fractures in non-venous nitinol stents. However, a dedicated self expanding nitinol venous stent, engineered for improved durability, underwent up to 50 years of simulated loading on the bench with 15% (3/20) of stents experiencing fractures at 50 years, compared with fractures in 35% (14/40) of non-venous stents tested to 1.4 years; no statistical testing was performed as durations do not match and the objective was to demonstrate the test method. The presented fatigue test method is a suitable approach for evaluating the durability of stents intended for venous use. Venous stents demonstrated superior fatigue resistance compared with non-venous stents via invitro hip flexion testing.

Changes in Lower-Extremity Gait Biomechanics Following High-Cadence Cycling.

We sought to investigate the lower-extremity biomechanics underlying increased gait velocity following high-cadence cycling. Ground reaction forces (GRF) and lower-extremity kinematics and kinetics were recorded as 15 healthy adults walked at a self-selected pace prior to and immediately following a 15 min bout of cycling at a cadence of 75 rotations per minute. Propulsive GRF and stance-phase peak dorsiflexion and knee extension angles increased, while peak plantarflexion and hip extension angles decreased. Swing-phase peak dorsiflexion, plantarflexion, knee flexion, and hip flexion angles increased, while peak knee extension angle decreased. Peak dorsiflexion, knee extension, and hip extension angular velocity also increased during swing. No changes in peak joint moments were observed; however, peak positive ankle, knee, and hip joint power generation increased following cycling. Completing high-cadence cycling improves gait velocity by increasing propulsive GRF; increasing joint angular velocity during the swing phase of gait for the ankle, knee, and hip; and increasing positive power production by the ankle, knee, and hip during the stance phase. Increased gait velocity post cycling exercise did not increase lower-extremity joint moments. Cycling may be a viable exercise-based modality for increasing gait velocity, especially in populations where gait ability or joint loading is of particular concern.

A Contemporary analysis of tackle height: Implications for head injury risk and tackler technique in Rugby Union

Rugby tackles pose significant head injury risks, raising concerns for players' well-being. Despite advocating for lower tackle heights for safety, limited research exists explaining how tackle height influences head characteristics and tackler technique. This study aimed to investigate the effects of two tackle heights, aligned with recent law changes in the community game, on head and joint kinematics for both tackler and the ball carrier. To strengthen ecological validity, innovative techniques were employed, including markerless motion capture and Inertial Measurement Units (IMUs), for tracking of the tackler's joint kinematics and head accelerations until ground contact, addressing a key limitation in previous research. Ethical approval was granted by Cardiff Metropolitan University. Ten male participants (mean ± SD age: 22 ± 3 years, stature: 184 ± 10 cm, mean mass: 94 ± 15 kg) alternated between tackler and ball carrier roles, executing upper and lower body tackles. Theia3D markerless motion capture software (Theia3Dv2022.1.0.2309, Theia Markerless, Inc., Kingston, ON, Canada) and Vicon IMeasureU Blue Trident dual-G IMUs measured tackle height's impact on head and joint kinematics. Discrete joint angles at key events and continuous joint angles normalised from 0% at Step 1 to 100% at Contact were exported. Peak head accelerations and continuous normalised head acceleration data were exported. Statistical analyses included a paired t-test for discrete joint angle data and the Wilcoxon Rank Sum Test for peak linear and angular accelerations. Cohen’s d and effect sizes were calculated for respective analyses. One-dimensional statistical parametric mapping (SPM) and one-dimensional statistical non-parametric mapping (SnPM) facilitated statistical differences across continuous variables of interest. Significant increases (P < 0.05) were noted in ball carriers' inertial head kinematics in the upper body tackle, while no such distinctions were observed for tacklers. The low tackle condition consistently exhibited substantial reductions in bilateral hip flexion, particularly during contact (Effect size; lead: −1.866; rear: −1.977). Lumbopelvic flexion significantly decreased in each event for the low tackle condition, with the largest effect size during contact (−3.91). These findings underscore the heightened inertial loading with higher tackles, indicating an elevated risk of head injury, despite current tackle height regulations. The adjustments made by the tackler in response to varying tackle heights are not evident in knee flexion. Increased knee flexion during the preparatory phase could alleviate the necessity for such a flexed lumbopelvic angle. This study, utilising innovative techniques, highlights the potential for more ecologically valid approaches to biomechanical research in rugby tackling.

Assessment of function and muscle strength after endoscopic iliopsoas tenotomy to treat iliopsoas impingement after total hip arthroplasty.

The objective of this study was to evaluate the functional outcome during follow-up (FU) after endoscopic tenotomy for iliopsoas (IP)-cup impingement and to quantitatively analyze the hip flexion strength. This was a monocentric, retrospective cohort study of a single surgeon series. Functional assessment was based on the modified Harris score, the Oxford score and the visual analog scale score. Strength was measured with a handheld dynamometer in the sitting and lying position. Thirty-six IP tenotomies for cup impingement were performed between May 2013 and November 2021. Seven (19%) patients were lost to FU. At the time of tenotomy, the mean (standard deviation) age was 62,6 (12,2) and BMI was 26,5 (4,1). The mean FU time after tenotomy to the last FU was 3,6 (0,8) years. All three outcome scores improved from preoperatively to six months postoperatively (p < 0.001). There were no significant change from six months to last FU. The minimal clinically important difference (MCID) of the modified Harris score was set at 25. 20 (69%) patients had values that exceeded the threshold at one month and six months and neutral 19 (65.5%) had values that exceeded the threshold at the last FU. The limp symmetry index concerning hip flexion strength was 63% at 90° and 40% at 30° at the last FU. Most patients significantly improved their outcome scores after endoscopic iliopsoas tenotomy, with results remaining consistently stable over time. Despite a significant loss in hip flexion strength, the majority of patients did not report any impairment of their quality of life. Level III, Retrospective cohort study.

Identifying iliotibial band graft length and incision site may minimise the potential risk of harming adjacent structures: A novel approach for surgeon guidance.

The Iliotibial band (ITB) is a fibrous thickening of the fascia lata originating at the iliac crest and inserting at Gerdy's tubercle on the lateral tibia. The ITB significantly contributes to lateral knee stabilisation. Due to its size, tensile strength and easy access, it is widely used in orthopaedic surgery as an autograft during reconstruction procedures. Although ITB harvesting may result in complications, such as reduced knee extension or hip flexion, no safety margins or guidelines have been proposed for the procedure. Our aim was to determine the maximal safe length of an ITB graft, that is, that does not harm the lateral collateral ligament (LCL), tensor fasciae latae (TFL), gluteus maximus (GM) or adjacent structures, and reduce the complication rate. The study included 50 lower limbs of 25 human cadavers, previously fixed in 10% formalin solution. The inclusion criterion was the lack of visible signs of surgical interventions in the study region. Forty lower limbs were included in the study: 16 female (mean age 83.1 ± 3.4 years) and 24 male (mean age 84.2 ± 6.8 years). Dissection was performed with a previously established protocol. Morphometric measurements were then obtained twice by two researchers. The mean femur length was 404.8 mm [female (F) = 397.3 mm, male (M) = 409.9 mm, standard deviation (SD): F = 23.8 mm, M = 24.1 mm]. The mean ITB length was 318.9 mm (F = 309.4 mm, M = 325.2 mm, SD: F = 25.7 mm, M = 33.7 mm). Longer femurs were associated with longer ITB (p < 0.05). The mean distance from the insertion of the GM to the myofascial junction of TFL and ITB was 34.6 mm (F = 34.5 mm, M = 34.6 mm, SD: F = 3.2 mm, M = 3.3 mm). The longer femurs or ITBs demonstrated a greater distance from GM insertion to the myofascial junction of the TFL and ITB (p < 0.05). ITB grafts longer than 21 cm may contribute to the greater risk of TFL rupture. Based on simple measurements of the femur length, the surgeon may assess approximate ITB length, and thus assess the length of the maximal graft length. Moreover, to avoid harming the LCL, the incision should be performed 5 cm proximal to the articular surface of the lateral femoral condyle or 13 mm proximal to the lateral femoral epicondyle. Such preparation and preoperative planning may greatly reduce the risk of complications during ITB harvesting, while performing, for instance, the over-the-top technique for anterior cruciate ligament reconstruction in skeletally immature patients. Basic I.

Vertical or Horizontal (Bikini) Incision for Direct Anterior Total Hip Arthroplasty: Outcomes of Early (

BackgroundThe horizontal ‘bikini’ incision for direct anterior approach (DAA) total hip arthroplasty has gained popularity due to its early wound healing characteristics; however, the nonextensile nature of this approach may pose problems in treating early complications. This study sought to characterize the outcomes of early revision (<90 days) in patients who underwent anterior hip arthroplasty utilizing either a traditional longitudinal incision or a horizontal (bikini) incision. MethodsThis retrospective study identified patients who underwent DAA primary total hip arthroplasty with a subsequent DAA revision within 90 days. Patients were divided into two cohorts based on the orientation of their incision: either ‘longitudinal incision’ (in accordance with the Smith Peterson interval) or ‘horizontal bikini incision’ (in accordance with the hip flexion crease). ResultsThere were 74 patients who underwent DAA revision arthroplasty within 90 days of primary arthroplasty; 65 had a longitudinal incision, and 9 had a horizontal (bikini) incision. In the longitudinal incision group, 2 patients (3.1%) required plastic surgery closure, and 11 patients (16.9%) required additional operations. Of the 9 bikini incision patients, 6 patients required the assistance of plastic surgery closure, and 7 patients required multiple orthopaedic operations. ConclusionsOur study suggests that a horizontal bikini incision is less forgiving in the early postoperative period if a more extensile exposure is needed for revision surgery, as measured by the need for plastic surgery and additional returns to the operating room. In our cohort, the longitudinal incision allowed for the management of early surgical complications with less morbidity.

Muscle Strength Asymmetries of the Lower Limbs and Trunk in Ballet Dancers.

Ballet dancers are expected to use their bodies symmetrically during training, because dance movements are performed on both sides. However, there is a general belief that ballet training encourages the use of one side of the body more than the other. Frequent repetition of a particular exercise can lead to body asymmetries and musculoskeletal injuries. The aim of this cross-sectional study was to investigate the presence of lower limbs and trunk muscle strength asymmetries in ballet dancers and secondly to assess whether there is a difference between professional dancers and ballet students. Ballet students (n=19) and professional ballet dancers (n=23) performed maximal voluntary isometric contractions of the trunk (flexion, extension, lateral flexion), hip (flexion, extension, adduction, abduction, external and internal rotation), knee (flexion, extension) and ankle (flexion, extension) on isometric dynamometer. The results showed that the percentage of ballet dancers with contralateral muscle strength asymmetries >10% ranged from 22.5% (ballet students) to 31.6% (professional dancers). The percentage of ballet dancers deviating by >10% from the normative maximum torque agonist/antagonist ratio ranged from 56.5% to 100%. A statistically significant difference between ballet students and professional ballet dancers was found in the trunk flexion/extension ratio (t(40) = -3 .55; p = 0.001; d = 0.55). This study revealed strength asymmetries in the lower limbs and trunk in ballet dancers, both professionals and students. Further research is needed to develop appropriate complementary exercise to address and eliminate asymmetries in muscle strength in ballet dancers.

Reliability of Hip Strength Assessment in Young Active People with Hip Dysplasia: An Examination in Student Circus Artists.

Developmental dysplasia of the hip (DDH) is common in performing artists and other young active individuals and involves abnormalities in bony morphology of the acetabulum and proximal femur that can negatively impact walking biomechanics, muscular strength, quality of life, and sleep. Rehabilitation for hip-related conditions should target known modifiable impairments such as hip muscle strength, though a reliable method of assessment in this population remains unclear. To determine the inter- and intra-rater reliability of hip muscle strength assessments using handheld dynamometry (HHD) in young active circus artists with DDH. Reliability of hip strength in all planes was assessed using HHD in 21 adult performing circus arts students (mean age 21.3 yrs [3.2]; 13 M, 5 F, 3 NB) with symptomatic radiologically and clinically diagnosed hip dysplasia. The reliability of average peak force and absolute peak force were expressed for each position tested. Reliability was assessed using intraclass correlation coefficients (ICC) with standard error of measurement (SEM) and minimal detectable change (MDC) values calculated to improve clinical interpretability. Good to excellent inter-rater reliability resulted for all hip muscle strength testing positions, ICC=0.88 (95%CI 0.70 to 0.95) to ICC=0.97 (0.92 to 0.99), except average peak hip flexion strength, ICC=0.71 (0.28 to 0.88). Absolute peak hip abduction, ICC=0.77 (0.16 to 0.94), and adduction strength, ICC=0.72 (-0.55 to 0.92), demonstrated the lowest intra-rater reliability. Transverse plane strength measures (rotation) produced the lowest SEM and MDC values followed by the frontal plane (abduction/adduction) and sagittal plane (flexion/extension). HHD is an appropriate and reliable method to assess hip muscle strength in circus artists with DDH.

Sustainable effectiveness of kinetic chain stretching on active hip flexion movement and muscle activation for hamstring tightness: A preliminary investigation.

Conventional hamstring (HAM) stretching therapeutic effects are not substantiable in neuromusculoskeletal conditions with HAM tightness or shortness. We developed a kinetic chain stabilization exercise to provide a more sustainable effectiveness in adults with HAM tightness. However, its therapeutic effects and underlying motor mechanisms remain unknown. To compare the effects of traditional active HAM stretching (AHS) and kinetic chain stretching (KCS) on electromyographic (EMG) amplitude and hip flexion range of motion (ROM) in participants with HAM tightness. In this randomized controlled trial, 18 participants (mean age: 25.01 ± 2.47 years) with HAM tightness were assigned to the AHS or KCS group. Hip joint movement, EMG amplitude, and onset times were recorded in the bilateral erector spinae, HAM, transverse abdominis/internal oblique (IO), external oblique (EO), and rectus abdominis during a straight leg raise test. Compared to AHS, KCS led to greater increase in the hip flexion ROM and EMG activation amplitudes in the left and right EO and left IO. Post-test hip flexion ROM data in both the groups were higher than the pre-test data. KCS produced more sustainable effectiveness in hip flexion movement and EMG motor control patterns in participants with HAM tightness than AHS.

Effects of Pilates-Combined Training on the Improvement of Flexibility and Pain Relief in Elite Fencers

PURPOSE: This study aimed to examine the effects of incorporating Pilates into the training regimen of elite fencers, focusing on enhancing flexibility and alleviating pain commonly experienced in the sport.METHODS: Twenty-five collegiate male elite fencers were stratified into two groups: a fencing training group (FT, n = 12, age = 18.92 ± 1.08, weight = 71.78 ± 7.43 kg, body mass index [BMI] = 22.32 ± 2.09 kg/m2) and a fencing-Pilates combined training group (FPT, n = 13, age = 19.92 ± 0.64, weight = 70.97 ± 9.14 kg, BMI = 22.61 ± 1.71 kg/m2). Evaluations, including body composition; physical fitness factors; shoulder strength; and joint range of motion in the upper extremities, lower extremities, neck, and spine, were conducted before and after 12 weeks of the intervention. Additionally, examinations of pain catastrophizing and anxiety levels during competitive engagements were performed.RESULTS: There were no statistical differences in body composition, physical fitness factors, or upper-limb strength between the FT and FPT groups. However, the FPT group exhibited a notable enhancement in shoulder abduction of the upper limb when holding a sword, in contrast to the unchanged metrics observed in the FT group. The positive impact of Pilates-combined treatment on flexibility extended to the neck; waist; and lower extremities, such as hip flexion, hip extension, hip abduction, medial rotation, and ankle dorsiflexion, coupled with significant improvements in psychological aspects, such as pain relief and related competition anxiety.CONCLUSIONS: This study confirmed that Pilates-combined treatment can have a beneficial effect on improving flexibility and pain in fencers, and verified the effectiveness of Pilates as an auxiliary training method for elite fencers.

Direct contact and very rapid valgus distortion characterise the injury mechanism of anterior cruciate ligament ruptures in judo.

To analyse anterior cruciate ligament (ACL) rupture (ACLR) injury mechanisms in competitive judo using systematic video analysis, focusing on contact situations and biomechanics. Seventeen videos of judo competitions wherein athletes developed ACLRswere included and retrospectively evaluated by five analysts. In all videos, the momentof initial contact and the index frame were defined. The judo techniques leading to the injury; the occurrence of direct contact, indirect contactor noncontact mechanisms; the time interval between the initial contact and index frame; the positions of the hip, kneeand foot in relation to the initial contact and index frame; and the balance status during the initial contact and index frame were recorded. Eleven (65%) of ACLRs in judo involved direct contact. The mean time interval between initial contact and index frame was 15 ± 22 ms. Thirteen (77%) athletes were not balanced at initial contact. In the index frame, the hip was abducted in all cases and in combination with internal rotation in 12 (71%) cases. From initial contact to index frame, hip flexion increased in all cases; at index frame, the knee joint was internally rotated relative to the trunk in 12 (71%) cases, and the knee flexion angles increased from the initial contact. In the index frame, the foot was externally rotated relative to the knee in 12 (71%) cases, and severe valgus development of the knee with valgus collapse was observed in 14 (82%) cases. A direct attack on the knee was the most common injury mechanism observed. Valgus distortion appears to be the most important component of the mechanism of injury. With this knowledge, 'modified defence reactions'for specific judo techniques can be developed to reduce the injury risk. Level IV.

The effect of forward postural lean on running economy, kinematics, and muscle activation.

Running economy, commonly defined as the metabolic energy demand for a given submaximal running speed, is strongly associated with distance running performance. It is commonly believed among running coaches and runners that running with increased forward postural lean either from the ankle or waist improves running economy. However, recent biomechanical research suggests using a large forward postural lean during running may impair running economy due to increased demand on the leg muscles. This study tests the effect of altering forward postural lean and lean strategy on running economy, kinematics, and muscle activity. 16 healthy young adult runners (23±5 years, 8M/8F) ran on a motorized treadmill at 3.58m/s using three postural lean angles [upright, moderate lean (50% of maximal lean angle), and maximal lean] and two strategies (lean from ankle and lean from waist [trunk lean]). Metabolic energy consumption, leg kinematics, and muscle activation data were recorded for all trials. Regardless of lean strategy, running with an increased forward postural lean (up to 8±2 degrees) increased metabolic cost (worsened economy) by 8% (p < .001), increased hip flexion (p < .001), and increased gluteus maximus (p = .016) and biceps femoris (p = .02) muscle activation during the stance phase. This relation between running economy and postural lean angle was similar between the ankle and trunk lean strategies (p = .743). Running with a large forward postural lean reduced running economy and increased reliance on less efficient extensor leg muscles. In contrast, running with a more upright or moderate forward postural lean may be more energetically optimal, and lead to improved running performance.

Effect of soft tissue, range of motion and muscle strength on deep squatting

The purpose was to clarify the effects of soft tissues such as muscles and fat, range of motion of the hip, knee and ankle, knee extension and ankle dorsiflexion muscle strength and muscle activity on deep squatting. The participants were 18 healthy university students. Physical characteristics, circumference, subcutaneous fat thickness, and range of motion were measured. After that, they performed deep squatting and lower limb muscle strength was measured. Muscle activities in lower limb during performance was also measured. Statistical tests were performed on the differences between the able group and the unable group, with each item as the dependent variable. Body weight, BMI, abdominal circumference, and tibialis anterior muscle activity were significantly lower in the able group (able to perform a deep squat), than in the unable group. Additionally, range of motion of the hip flexion and ankle dorsiflexion were significantly higher in the able group than in the unable group. It was clarified that soft tissues characteristics are connected to deep squatting in addition to range of motion.

Impaired Perception of Body-Weight Distribution Marks Functional Mobility Problems in Patients Undergoing Total Hip Arthroplasty.

Hip osteoarthritis and total hip arthroplasty imply damaged articular and periarticular structures responsible for proprioception, and this damage may impair the accurate perception of body-weight distribution. In this study, we investigated proprioceptive abilities and accuracy perceiving body-weight distribution in patients undergoing total hip arthroplasty, and we assessed the associations between these abilities and body perception accuracy with functional mobility testing in 20 patients scheduled for total hip arthroplasty and 20 age-matched healthy participants. We assessed (a) absolute error in hip joint position sense (AE-JPS), (b) absolute error in body-weight distribution (AE-BWD) during standing and sit-to-stand tasks with open and closed eyes, and (c) functional mobility with the Timed Up and Go Test (TUG). We assessed patients undergoing hip arthroplasty before (T0) and five days after their surgery (T1), while control participants underwent a single evaluation. Relative to controls, participants undergoing surgery showed higher AE-JPS at 15° of hip flexion at T0 (p = .003) and at T1 (p = .007), greater AE-BWD during sit-to-stand with open eyes at T1 (p = .014) and with closed eyes at both T0 (p = .014) and at T1 (p < .001), and worse TUG at both T0 (p = .009) and T1 (p < .001). AE-BWD during sit-to-stand with closed eyes positively correlated with TUG at T0 (r = 0.55, p = .011) and at T1 (r = 0.51, p = .027). These findings suggested that impairments in body-weight distribution perception were evident both before and immediately after total hip arthroplasty, suggesting that these impairments may regularly mark these patients' functional mobility problems.

Effect of hamstring flexibility on cervical range of motion and deep neck flexor endurance in healthy young adults: A study to explore myofascial tensegrity network

IntroductionAccording to the concept of biotensegrity, the whole body consists of fascial lines. The relationship between muscles and fascia is important to ensure full and proper range of motion. This study investigated the effect of hamstring flexibility on cervical range of motion and deep neck flexor muscle endurance. The aim was to explore the relationship between the hamstring muscles and neck region in the myofascial tensegrity network. MethodSixty healthy participants with a median age of 22.0 years (24 male, 36 female) were included. Hamstring flexibility was categorized as “normal (n = 31)” or “limited (n = 29)” according to hip flexion angle (HFA) using the passive straight leg raise (PSLR) test. Active cervical range of motion was measured by the Clinometer smartphone application, and the following movements were recorded: flexion, extension and lateral flexion. The craniocervical flexion test was performed to evaluate deep neck flexor endurance using performance index and highest-pressure score. The Mann-Whitney U test was used for statistical analysis. ResultsNo significant differences in cervical range of motion were observed between the groups (p > 0.05). Participants with limited hamstring flexibility presented lower deep neck flexor muscle endurance scores (performance index and highest-pressure score) than participants with normal hamstring flexibility (p = 0.002, and p = 0.012, respectively). ConclusionThe results suggest that hamstring flexibility can influence deep neck flexor muscle endurance in healthy young adults. This preliminary clinical finding supports the hypothesis of a myofascial network between the hamstring muscles and neck region.

Influence of aging on the relation between head control and hip joint kinematics during crossover stepping.

Falls in older individuals are a serious health issue in super-aged societies. The stepping reaction is an important postural strategy for preventing falls. This study aimed to reveal the characteristics of lateral stepping in response to mechanical disturbance by means of an analysis of the hip joint kinematics in the stepping leg and head stability during crossover steps. The participants included 11 healthy older and 13 younger individuals. An electromagnet-controlled disturbance-loading device induced crossover steps due to lateral disturbance. Responses were measured using a motion capture system and force plates. The righting reaction of the head was quantified by lateral displacement (sway), neck joint kinematics (angle displacement, angular velocity), and neck joint moment during crossover stepping. Moreover, the relationship between the neck lateral bending moment and angular velocity of hip flexion/adduction of the stepping leg was examined. The lateral head sway was significantly larger in the older participants (1.13±0.7 m/s2) than in the younger individuals (0.54±0.3 m/s2); whereas, the angle displacement (older -14.1±7.1 degree, young -8.3±4.5 degree) and angular velocity (older 9.9±6.6 degree/s, 41.2±27.7 degree/s) of the head were significantly lower in the older than in the younger participants. In both groups, the moment of neck lateral bending exhibited a significant negative correlation with the hip flexion angular velocity of the stepping leg. Correlation analysis also showed a significant negative correlation between the neck lateral bending moment and hip adduction angular velocity only in the older group (r = 0.71, p<0.01). In conclusion, older individuals increased instability in the lateral direction of the head and decreased righting angle displacement and angular velocity of the head during crossover steps. The correlation between neck moment and hip flexion/adduction angular velocity suggested a decrease in step speed due to increased neck muscle tone, which could be influenced by vestibulospinal reflexes.

Exploring functional strength changes during nusinersen treatment in symptomatic children with SMA types 2 and 3.

The Hammersmith Functional Motor Scale-Expanded (HFMSE) is a validated outcome measure for monitoring changes in functional strength in patients with spinal muscular atrophy (SMA). The objective of this study was to explore changes in HFMSE item-scores in children with SMA types 2 and 3a treated with nusinersen over a period of six to twenty months. We stratified patients according to motor ability (sitting and walking), and calculated numbers and percentages for each specific improvement (positive score change) or decrease (negative score change) for the total group and each subgroup and calculated frequency distributions of specific score changes. Ninety-one percent of the children showed improvement in at least 1 item, twenty-eight percent showed a score decrease in 1 or more items. In the first six to twenty months of nusinersen treatment motor function change was characterized by the acquisition of the ability to perform specific tasks with compensation strategies (score changes from 0 to 1). Children with the ability to sit were most likely to improve in items that assess rolling, whilst children with the ability to walk most likely improved in items that assess half-kneeling. The ability most frequently lost was hip flexion in supine position.