Hip Position Research Articles

Influence of Changing Hip Position on Electromyographic Activities of Selected Trunk Muscles During Bridging Exercises in Healthy Subjects: A Cross-Sectional Study

Objective: The purpose of this study was to investigate how rectus abdominis, external oblique (EO), internal oblique (IO), erector spinae, multifidus (MF), and gluteus maximus (GMax) muscle activities change with different hip positions during back and side bridging exercises. MethodsThirty-six healthy individuals participated in this cross-sectional study and performed 6 exercises including back bridging (BB) in neutral hip position, BB with internal rotation, BB with external rotation (BB + ER), side bridging with hips in neutral (SB), side bridging with hips in flexion (SB + HF), and side bridging with hips in extension (SB + HE). Muscle activity was observed using surface electromyography, normalized using maximum voluntary isometric contraction. Repeated-measures 1-way analysis of variance compared muscle readings for each position. ResultsBack bridging with internal rotation showed significant differences in EO (P = .01) and IO (P < .001) compared with other BB positions. Multifidus and GMax differed significantly in BB + ER (P = .04). Side bridging exhibited significant differences in EO (P = .02; P < .001) and IO (P < .001) compared with the other 2 SB positions, with peak in SB + HF. Erector spinae, MF, and GMax also differed significantly (P < .001, P = .02, P < .001, respectively) with peak in SB + HE. ConclusionThe findings revealed that EO and IO muscles were most active during BB with internal rotation, whereas the MF and GMax muscles were most active during BB + ER. In terms of SB, the EO and IO muscles were most active with either SB + HF or SB + HE, whereas the erector spinae, MF, and GMax muscles were most active with SB + HE.

Magnetic resonance imaging verification of anterior capsular impingement in the hip joint: A three-dimensional analysis

BackgroundThis study aimed to clarify whether the anterior hip capsular ligament is impinged between the acetabulum and femur during hip flexion or adduction and to determine the difference in the distance between the femur and capsular ligament in healthy adults and those with hip pain. MethodsMagnetic resonance imaging of the hip joint was conducted at the following hip positions: 0° of flexion, 60° of flexion, maximal flexion, and maximal flexion with adduction. A three-dimensional model of the capsular ligament and femur was constructed. The minimal distance between the femur and capsular ligament, termed the capsule-femur distance, was computed. Because a capsule-femur distance of 0 mm indicates contact between the femur and the capsular ligament, that is, capsular impingement, the distance in each position was compared for each group using a one-sample t-test. The capsule-femur distance in the various groups and for different positions was compared using a split-plot analysis of variance. FindingsFifteen healthy individuals and sixteen individuals experiencing hip pain were enrolled. The capsule-femur distance was significantly greater than 0 mm in all positions in both groups, and none of the groups had a capsule-femur distance of 0 mm. The capsule-femur distance was significantly longer in the other positions than in the 0° flexion position, and significantly longer in the hip pain group than in the healthy group. InterpretationCapsular impingement did not occur in either group, even during hip flexion or adduction. Furthermore, the capsule-femur distance was longer in the hip flexion and hip pain groups.

Pelvic and Lower Limb Kinematics in Individuals With Chronic Low Back Pain During Sit-to-Stand Function: A Cross-Sectional Study

ObjectivesThe aim of this study was to investigate the 3-dimensional movement kinematics of pelvic and lower limb joints in CLBP subjects, compared to healthy individuals, utilizing a functional data analysis (FDA) approach. MethodsIn this study, a 7-camera Qualisys motion capture system was employed to record the kinematics of the pelvic, hip, knee, and ankle joints in 20 patients with low back pain (LBP) and 20 control subjects on both sides during the sit-to-stand motion. An FDA statistical approach was utilized to compare the data collected over time between the 2 groups. The STS task was divided into two distinct phases: the prelift off phase (pre-Lo) and the postlift off phase (post-Lo). ResultsDuring the “pre-Lo phase” of the STS motion, our statistical analysis revealed that the only significant difference between the two groups was a decreased medial rotation (P = .00) in the hip joint position of LBP patients on their dominant side, in comparison to healthy subjects. As for the “post-Lo phase,” the LBP group exhibited a more anterior pelvic tilt position (P = .00) and increased pelvic counterclockwise rotation (P = .03) in the sagittal and transverse planes when compared to the control group. Regarding hip joints, the LBP group demonstrated a more flexed position (indicative of reduced extension) on both the dominant (P = .00) and nondominant (P = .00) sides, coupled with diminished abduction (P = .04) and internal rotation (P = .03) of the hip on the dominant side. In relation to the knee and ankle joints, the results indicated a more adducted knee position (P = .00) and decreased ankle joint flexion (P = .02) on the dominant side in CLBP subjects when compared to the healthy group during the STS motion. ConclusionOur findings indicate that patients with CLBP exhibited distinct kinematic patterns in the pelvic and lower limb joints during the STS motion. These kinematic alterations primarily manifest in the joints of the dominant limb, with most of the differences observed during the second phase (postlift off phase) of the motion. It appears that these changes in pelvic and lower limb joint kinematics should be taken into account when planning future rehabilitation programs for CLBP patients engaged in this task.

Joint-line obliquity angle is significantly affected by hip abduction and adduction: A simulated analysis.

Different methods for quantifying joint-line obliquity (JLO) have been described, including joint-line obliquity angle (JLOA), Mikulicz joint-line angle (MJLA) and medial proximal tibial angle (MPTA). The goal of the present study was to quantify the variation of JLOA based on the position of the hip. The hypothesis of our study is that JLO is significantly influenced by the abduction/adduction of the limb, unlike MJLA. One hundred long-leg-weightbearing X-rays were used. At time 0 and after 30 days, two observers performed different measurements, including (1) distance between pubic symphysis and center of the femoral head, (2) distance between center of the femoral head and center of the ankle joint, (3) distance between center of the ankle and medial malleolus, (4) hip-knee-ankle angle, (5) MPTA, (6) lateral distal femoral angle, (7) joint-line congruency angle, (8) JLOA, (9) MJL and (10) angle between Mikulicz line and line perpendicular to the ground. The changes of the JLOA based on the position of the hip (abducted, neutral, bipedal stance adduction and monopodal stance adduction) were calculated with trigonometric formulas and with simulation on an orthopaedic planning digital software. The JLOA change between adducted and abducted positions was on average 12.8° (SD 0.9 mm). The MJL did not vary significantly based on hip position. The adduction/abduction of the lower limb has a considerable impact on JLOA. Methods like MJLA which are not affected by hip position should be preferred for JLO evaluation. Diagnostic study, level III.

Influence of texting while walking on lower extremity gait function in young adults

Texting while walking (TWW) is a dual-task activity that young adults perform in their everyday lives. TWW has been reported to affect gait characteristics such as gait speed, stride length, and cadence. However, the influence of TWW on lower extremity gait function has not been investigated. Therefore, the purpose of this study was to quantify gait function by examining gait symmetry and using a time series analysis. Twenty-eight young adults (14 males, 14 females) walked at their preferred speed for 10 m as a baseline condition and a 10 m TWW task. Three-dimensional segment tracking was achieved utilizing a lower extremity and trunk marker set and the Model Statistic was used to test for statistical differences between the hip, knee, and ankle angular joint positions. The hip yielded the most asymmetries (25 out of 101 points) throughout the gait cycle, while asymmetries for the knee and ankle joints yielded 16 out of 101 points and 11 out of 101 points, respectively. The outcomes of this study suggest there are differences between baseline and TWW gait symmetry, however, the percentage of the gait cycle affected was less than 25 % - indicating gait function is not strongly influenced by texting while walking in young adults.

Student radiographers’ knowledge and experience of lateral hip X-ray positioning: A survey

IntroductionThe horizontal beam lateral (HBL) position technique for X-ray imaging has been used for nearly a century; however, this can be challenging for the patient and the practitioner, as it potentially compromises patient dignity. This study explores student radiographers' knowledge and experience of lateral hip positions and their impact on diagnostic quality and patient dignity. MethodA cross-sectional mixed-method online survey of undergraduate diagnostic radiography students was completed. Likert scale assessments, rank ordering questions, and free-test qualitative responses were utilised for questions on knowledge and experience of different positioning, ease to obtain, patient dignity, diagnostic quality, and need for repeats. Data analysis included descriptive statistics and cross-tabulation non-parametric analysis against variables of age, gender and year of study. ResultsResponses were received by n = 42/158 students, a response rate of 27%. The HBL position was the most commonly repeated image (76.6%); the qualitative themes included HBL image quality issues and difficulty in the HBL positioning for elderly or frail patients, often in discomfort and pain. Analysis of student responses to perceived patient dignity in positioning identified 73.8% found the HBL undignified, and 85.7% agreed the Clements-Nakayama (CN) position would be more dignified for patients. The diagnostic image quality of the HBL position (64.2%) was compared to the CN alternative axiolateral (66.6%). Comparison of ease of obtaining the correct position for HBL (47.6%) was higher than CN position (28.6%); this could be due to the lack of experience n = 3/42 (7.1%) of this position. ConclusionOverall, student radiographers' experience and knowledge of various lateral hip positions observed in clinical practice was good. The CN position scored high for diagnostic image (66.6%) and dignity for the patient (85.7%), over the often repeated HBL position (76.6%), which scored lower for image quality (64.2%) and dignity (76.6%). Implications for practiceRadiographers should advocate for professional autonomy and explore alternative positioning techniques. Further investigation into the CN position's utilisation, image quality and radiation dose in England is recommended.

Hip Circumferential Labral Reconstruction Provides Similar Distractive Stability to Labral Repair After Cam Over-Resection in a Biomechanical Model

To evaluate the change in hip distractive stability after a cam over-resection, labral tear, repair, labrectomy, or circumferential 6- or 10-mm labral reconstruction in a biomechanical model. Ten fresh-frozen matched-pair human cadaveric hips were analyzed using a materials testing system to measure the force and distance required to disrupt the suction seal of the hip (1) with an intact capsule and labrum; (2) after a capsulectomy and labral repair; (3) after a capsulectomy, 5-mm cam over-resection and labral repair; (4) after a capsulectomy, 5-mm cam over-resection and labral tear; (5) after a capsulectomy, 5-mm cam over-resection and labrectomy; and (6) after a capsulectomy, 5-mm cam over-resection and a 6- or 10-mm circumferential labral reconstruction with iliotibial band (5 hips each). Each specimen was retested at 0° flexion, 45° flexion, and 45° flexion and at 15° internal rotation and analyzed using nonparametric statistical methods. The Friedman test of differences was significant among structural conditions and hip positions (P= .001). In all positions, the resistive force that opposed the disruption of the suction seal in an intact hip was significantly greater compared with all other conditions. The resistive force for the capsulectomy, 5-mm cam over-resection and labrectomy condition was significantly less compared with almost all other conditions and hip positions. A qualitative suction seal was achieved in 20% of hip specimens with a 6-mm labral reconstruction, whereas a seal was in achieved 60% of specimens with a 10-mm labral reconstruction. After a cam over-resection, a circumferential labral reconstruction improves the distractive stability of a labral deficient hip, comparable to a labral repair or tear in a biomechanical model. Circumferential labral reconstruction may be a viable treatment option for patients with ongoing symptoms after hip arthroscopy with evidence of a cam over-resection and a deficient labrum.

Acute Effect of Post-activation Potentiation on Semi-dynamic Balance in Girl Gymnasts Aged 9–12

Background: Post-activation potentiation (PAP) is a novel warm-up method shown to improve sports performance. This study aimed to investigate the acute impact of this method on semi-dynamic balance while walking on the balance beam among female gymnasts aged 9–12 in Kerman city. Methods: Twenty healthy gymnasts volunteered to participate (height: 138.1±5.04 cm; mass: 40.7±3.12 kg) and were randomly divided into two equal sub-groups. The two groups attended the laboratory on two separate days, 48 hours apart. On the first day, the first sub-group performed a general warm-up (GWU), while the second sub-group performed a PAP warm-up. On the second day, the first sub-group switched to a PAP warm-up, and the second sub-group switched to a GWU. After the warm-up, the subjects took a two-minute rest, and then they walked on the balance beam while their movements were recorded using six motion analyzer cameras that captured the kinematic data of the shoulder, thigh, knee, and ankle joints. The data were processed using a low-pass Butterworth filter and analyzed using one-way ANOVA and paired t tests. Results: The results showed significant differences in shoulder, hip, knee, and ankle joint positions in proximal-distal movements following GWU and PAP warm-ups (P≤0.001). In addition, PAP caused a significant decrease in shoulder, hip, knee, and ankle joint positions in medial-lateral movements compared to GWU (P≤0.001, P≤0.001, P≤0.038, P≤0.001, respectively). Conclusion: PAP warm-up positively affects semi-dynamic balance factors in gymnasts. Given the importance of balance in gymnastics, PAP warm-up is recommended to improve sports performance.

Effects of differences in femoral anteversion and hip flexion angle on hip abductor muscles activity during clam exercise in females.

This study aimed to determine differences in the hip abductor muscle activity during clam exercise at different hip flexion and femoral anteversion angles. Thirty healthy females were divided into two groups based on the femoral anteversion angle: the excessive femoral anteversion group and the normal group. Clam exercise was performed at three different hip flexion angles (60°, 45°, and 30°). Tensor fascia latae, gluteus medius, and superior portion of gluteus maximus activities were measured during the exercise, and the results were normalized to the activity during maximum voluntary isometric contraction to calculate the gluteal-to-tensor fascia latae muscle activation index. The superior portion of gluteus maximus activities at a hip flexion of 60° and 45° were greater than that at 30°. The excessive femoral anteversion group had a lower gluteal-to-tensor fascia latae muscle activation index than the normal group; the gluteal-to-tensor fascia latae muscle activation index for hip flexion at 60° was higher than that at 45°, and the gluteal-to-tensor fascia latae muscle activation index for hip flexion at 60° and 45° were higher than that at 30°. Therefore, the femoral anteversion angle and hip joint position were related to the activity of the hip abductor muscles during clam exercise. These findings may provide a rationale for instructing exercises to maximize the activity of the hip abductor muscles in individuals with an excessive femoral anteversion angle.

Wearable Robot Design Optimization Using Closed-Form Human-Robot Dynamic Interaction Model.

Wearable robots are emerging as a viable and effective solution for assisting and enabling people who suffer from balance and mobility disorders. Virtual prototyping is a powerful tool to design robots, preventing the costly iterative physical prototyping and testing. Design of wearable robots through modelling, however, often involves computationally expensive and error-prone multi-body simulations wrapped in an optimization framework to simulate human-robot-environment interactions. This paper proposes a framework to make the human-robot link segment system statically determinate, allowing for the closed-form inverse dynamics formulation of the link-segment model to be solved directly in order to simulate human-robot dynamic interactions. The paper also uses a technique developed by the authors to estimate the walking ground reactions from reference kinematic data, avoiding the need to measure them. The proposed framework is (a) computationally efficient and (b) transparent and easy to interpret, and (c) eliminates the need for optimization, detailed musculoskeletal modelling and measuring ground reaction forces for normal walking simulations. It is used to optimise the position of hip and ankle joints and the actuator torque-velocity requirements for a seven segments of a lower-limb wearable robot that is attached to the user at the shoes and pelvis. Gait measurements were carried out on six healthy subjects, and the data were used for design optimization and validation. The new technique promises to offer a significant advance in the way in which wearable robots can be designed.

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.

A biomechanical report of an acute lateral ankle sprain during a handball-specific cutting movement

ABSTRACT Biomechanical measurements of accidental ankle sprain injuries are rare but make important contributions to a more detailed understanding of the injury mechanism. In this case study, we present the kinematics and kinetics of a lateral ankle sprain of a female athlete performing handball-specific fake-and-cut manoeuvres. Three-dimensional kinematics and kinetics were recorded and six previously performed trials were used as reference. Plantarflexion, inversion, and internal rotation angles were substantially larger than the reference trials and peaked between 190 and 200 ms after initial ground contact. We observed a highly increased inversion and internal rotation moment. However, compared to the non-injury trials the data also revealed a reduction in the second dorsiflexion moment peak. Ground reaction forces were lower throughout the injury trial. Other parameters at initial ground contact including ankle and hip position, step length, and the traction coefficient indicate that a preparatory maladjustment occurred. This study adds valuable contributions to the understanding of lateral ankle sprains by building upon previously published reports and considering the shoe-surface interaction as an important factor for injury.

Hip External Rotation Decreases Ischiofemoral Distance: A Positive Correlation Between Cadaveric and Fluoroscopic Studies

PurposeTo determine the effect of hip external rotation or extension/adduction on minimizing the ischiofemoral distance (IFD) and assess the correlation between cadaveric and fluoroscopic IFD measurements in difference hip positions. MethodsThis cadaveric study involved 33 hip joints from 17 embalmed cadavers. IFD, the distance between the lesser trochanter and lateral ischium, was measured in different hip positions: neutral, external rotation at 30° and external rotation at 60° with the hip in both neutral extension and adduction as well as 10° hip extension and 10° hip adduction. Difference in IFD related to positions and correlation between cadaveric and fluoroscopic measurement were analyzed. ResultsIFD measurements showed that the greatest reduction occurred at 60° of external hip rotation, with a significant difference observed only between neutral and 60° external rotation in cadaveric groups (7.60±4.68 vs 5.05±3.48, 95% CI, 0.14 to 4.96; p=0.036). No substantial difference was observed between extension and adduction positions . Positive correlations were observed between cadaveric and fluoroscopic measurements, especially in the neutral position (r=0.492, p=0.004), external rotation at 30° (r=0.52, p=0.002), external rotation at 60° (r=0.419, p=0.015), and the extension/adduction positions combined with neutral rotation (r=0.396, p=0.023). ConclusionThe IFD significantly decreased with increasing degrees of hip external rotation, particularly at 60°. No significant reduction was observed in the extension/adduction positions. Additionally, positive correlations were observed between cadaveric and fluoroscopic measurements for specific hip positions: neutral rotation, external rotation at 30° and 60°, and extension/adduction at 10° with neutral rotation. Clinical RelevanceSurgeons can use this knowledge to improve hip impingement assessment through radiography, focusing on positions where IFD reduction is most notable. Understanding the relationship between hip positions and IFD can enhance the diagnosis of ischiofemoral impingement syndrome and benefiting patient care and outcomes.

Relation between Photogrammetry and Spinal Mouse for Lumbopelvic Assessment in Adolescents with Thoracic Kyphosis.

The evaluation of the lumbopelvic region is a crucial point during postural assessment in childhood and adolescence. Photogrammetry (PG) and Spinal Mouse (SM) are two of the most debated tools to properly analyze postural alignment and avoid misleading data. This study aims to find out the best linear regression model that could relate the analytic measurements of the SM with one or more PG parameters in adolescents with kyphotic postures. Thirty-nine adolescents (female = 35.9%) with structural and non-structural kyphosis were analyzed (13.2 ± 1.8 years; 1.59 ± 0.12 m; 47.6 ± 11.8 kg) using the SM and PG on the sagittal plane in a standing and forward-bending position, allowing for the measurement of body vertical inclination, lumbar and pelvic alignment, trunk flexion, sacral inclination during bending, and hip position during bending. Lordosis lumbar angles (SM) were significantly (r = -0.379, r = -0.328) correlated with the SIPS-SIAS angle (PG) during upright standing, while in the bending position, the highest correlation appeared among the sacral-hip (SM) and the sacral tangent (ST_PG; r = -0.72) angles. The stepwise backward procedure was assessed to estimate the SM variability in the bending and standing positions. Only in the bending position did the linear regression model reach high goodness-of-fit values with two regressors (ST_PG η2=0.504, BMI η2=0.252; adjusted- R2 =0.558, p < 0.001, CCC = 0.972, r = 0.763). Despite gold-standard methods reducing error evaluation, physicians and kinesiologists may consider photogrammetry as a good method for spinal curve prediction.

Influencing Factors for Joint Awareness After Total Hip Arthroplasty: A Cross-Sectional Study

Objective: Total hip arthroplasty (THA) is a common procedure nowadays, with hospitals easily reaching hundreds of surgeries a year and considering the cross-sectional nature. Joint awareness (JA) is indicative of the patient's adaptation and satisfaction after THA. The current study investigated the relationship between joint awareness, joint position sense (JPS), mobility level, activities of daily living, and hip pain level in patients with THA.&#x0D; Methods: This is a cross-sectional study involving 50 individuals with THA (31.48±55.14 weeks post-surgery; mean age was 54.32±18.28 years). Factors related to joint awareness were examined with linear regression analysis. Hip Joint position sense (JPS) was measured with a digital inclinometer, pain level was measured with a Visual Analog Scale (VAS), joint awareness was assessed with the Forgotten Joint Score-12, and mobility level was assessed with the Parker Mobility Index.&#x0D; Results: The factors that have a statistically significant effect on the joint awareness are age, pain, mobility, and BMI (p = 0.002, p = 0.040, p

Acute effects of Nordic hamstring exercise on hip and knee joints proprioception

Background and objectivesNordic Hamstring Exercise (NHE) is one of the best exercises proposed for injury prevention of hamstring muscles. However, its effects on lower extremity proprioception are unclear. The aim of this study was to investigate the immediate effects of a single bout of NHE on hip and knee joints’ proprioception. MethodsForty collegiate male soccer players participated in this study with a mean age of 22.85 ± 1.82 years and were randomized into either control (n = 20) or experimental (n = 20) groups. Each subject participated in pre-test measurements in which hip and knee active joints position sense (JPS) were assessed in standing and lying tasks using the image-capturing method. The experimental group then performed three sets of NHE with 10 repetitions in each set, while the control group rested for 10 min. Paired and independent t-tests were used for calculating the differences within and between groups on SPSS software, respectively. The level of significance was P ≤ 0.05. ResultsHip JPS in the lying task and knee JPS in both of the standing and lying tasks were impaired significantly after performing a single bout of NHE (P ≤ 0.05). However, the effects of this exercise on hip JPS in the standing task were not significant (P ≥ 0.05). ConclusionsNHE performing with three sets of 10 repetitions can significantly impair hip and knee JPS immediately after exercise and reduce the proprioception acuity of the lower limbs. It is recommended to perform this exercise at a time rather than before training or match sessions.

Optimal retractor insertion point for nerve safety during total hip arthroplasty: an anatomical study on the femoral and sciatic nerves in relation to hip motion.

Nerve injury is one of the most serious complications of total hip arthroplasty (THA). It is suspected to be a result from nerve compression or direct injury caused by an acetabular retractor. The anatomical relationship between the acetabular rim and the femoral and sciatic nerves, including hip motion, has not been investigated. This study aimed to identify the optimal position for retractor insertion during THA to prevent nerve damage. A total of 28 hip joints from 14 freshly frozen cadavers were used. Using an anterolateral approach, each cadaver was immobilised in the lateral decubitus position and deployed to measure the distance between the nerves and the acetabular rim, while the hip joint was changed to the extension, neutral, and flexion positions. Three femoral nerves were closest to the anterior margin of the acetabulum at 90° and 120° of extension and farthest away at 30° of flexion. The sciatic nerve was closest to the posterior margin of the acetabulum at 90° and 120° of flexion and farthest away at 30° and 150° of extension compared with the other points. To prevent nerve damage during THA, we suggest that the retractor be inserted at the points where the nerves are the farthest away, such as at 30° and 150°. The femoral and sciatic nerves vary in their movements depending on the hip position. Therefore, the safe insertion of a retractor is recommended for hip flexion of the femoral nerve and extension of the sciatic nerve. Additionally, it is important to carefully insert the retractor along the acetabular margin without penetrating the joint capsule. Overall, this study provides valuable insights into the anatomical location and movement of the femoral and sciatic nerves in relation to hip motion and can help inform surgical techniques for safer THA.

Evaluation of Scapular Dynamics in Sports Trainees

Background: The scapula provides stability and mobility for efficient upper-limb movement. Optimal scapular kinematics are essential for efficient force generation and injury prevention. Sports trainees, particularly those involved in sports requiring repetitive or high-intensity shoulder movements, are susceptible to injuries and performance limitations if associated with aberrant scapular mechanics. Understanding the intricacies of scapular dynamics is essential for designing tailored training interventions that enhance athletic performance. Rationale and objectives: Previous research has emphasized the need for sports-specific training protocols. The measurement of scapular rotation has gained significant attention. Evaluating asymmetries in scapular dynamics across various sports trainee populations is a step forward for the need for tailored interventions and injury prevention strategies in preventing injury and planning better exercise programs. The study uses a PALM meter for the measurement of scapular rotation. Methodology: 40 Subjects 19 to 24 years old from the sports authority of Andhra Pradesh, India, were studied after obtaining written informed consent. Scapular rotation measured in a neutral and with hands on the hip position. Root of the scapula (RSS), inferior angle of the scapula (IAS), and spinous processes (Sp) of C7 to T8 are taken as the anatomical landmarks. Measurements of scapular position taken in two arm positions: shoulder neutral, hands on hip. A right-angle triangle created by dropping a perpendicular line from the scapula's root to intersect the horizontal line between the scapula's inferior angle and the thoracic spine's closest spinous process (IAS-Sp). The hypotenuse represents the distance IAS to RSS, while the side opposite the angle θ is the distance IAS-Sp minus RSS-Sp. A positive result indicates upward scapular rotation, while a negative result indicates downward scapular rotation. Results and Conclusion: This cross-sectional study revealed variations in scapular rotation and the distances from spinous processes in the scapular position in neutral and hands-on Hip positions from right to left and male to female. Further studies are required to understand scapular rotation variations concerning various sports involving overhead activity, heavy weight lifting, endurance sports and anatomical variations, muscle activation patterns, or task demands. KEYWORDS: Scapular Rotation, Sports Trainees, Shoulder Movements, Scapular Mechanics, Athletic Performance.

The Effect of Concurrent Ankle and Hip Positions on Hamstring Function in Athletes

The Effect of Concurrent Ankle and Hip Positions on Hamstring Function in Athletes

Multivariate linear-mixed analysis of changes in anterior inferior iliac spine impingement incidence with posterior pelvic tilt: a computer simulation study.

It is well known that increased posterior tilt of the pelvis is an effective strategy for avoiding impingement of the femur with the pelvis during movement. Daily repetitive collisions become mechanical loads, and the more frequently they occur, the more tissue damage and pain they cause. Therefore, reducing the rate of occurrence of impingement is important to avoid aggravation of symptoms. This study aimed to evaluate the effects of changes in posterior pelvic tilt on the risk of impingement between the femur and the anterior inferior iliac spine (AIIS)/subspine in various functional postures. Patients with femoroacetabular impingement syndrome (FAIS) who were candidates for hip arthroscopic osteochondroplasty between October 2013 and June 2020 were included. A three-dimensional reconstructed model was used to simulate the incidence of impingement at 12 hip positions required for activities of daily living. We predicted value of the spatial incidence of impingement assumed that hip motion should exceed 130/30 degrees without impingement. Impingement was measured at three pelvic positions: an anterior tilt of 10°, in the functional pelvic plane and a posterior tilt of 10°. Multivariate linear-mixed models were used to assess the effect of covariate-adjusted posterior pelvic tilt on the impingement incidence in the AIIS region. AIIS type, center-edge angle, acetabular version and femoral version were used as covariates. The impingement rates and locations of the three pelvic tilt postures were assessed. Seventy-eight patients (60 males and 18 females; average age, 46 ± 15.1 years) with FAIS were analyzed. A multivariate linear-mixed model revealed a coefficient of -0.8% (95% confidence interval -0.9 to -0.7%; P < 0.001) for posterior pelvic tilt. Thus, posterior pelvic tilt affects AIIS impingement incidence. After adjusting for anatomical effects, the posterior pelvic tilt should be addressed to avoid impingement.