Terminal Stance Research Articles

A DEVICE-BASED (GAITON) SAGITTAL PLANE KINEMATICS ANALYSIS OF LOWER EXTREMITY JOINTS AMONG PATIENTS WITH KNEE OSTEOARTHRITIS – A METHODOLOGICAL APPROACH.

Background: Gait assessment is an effective method for identifying functional limitations associated with knee Osteoarthritis and understanding the relationship between disease symptoms and gait quality. Objective: To evaluate the mean difference in the kinematics of lower extremity joints among patients with knee osteoarthritis. Methods: A total of 20 people living with Knee OA were recruited as of 25th September 2024 in this prospective cross-sectional design study. The eligible participants were conveniently recruited from the SRM physiotherapy OPD based on voluntary participation after signing the informed consent. Adult participants aged 18 years and above, both sexes and able to walk independently without mobility aids were recruited and the joint kinematics were measured using the GaitOn Software, 2-dimensional analysis, and sagittal kinematic parameters of stance phase. Results: The mean age of the patients was 53.6 ± 7.3, and the mean BMI was 29.1±4.6. The one sample t-test demonstrated a statistically significant difference between kinematic angles of the lower extremity joint in sagittal plane of population mean (reference value) and sample mean (measured by GaitOn); Initial contact phase (hip: mean diff -4.06, p<0.01, ankle: mean diff 34.1, p < 0.0001), Loading response (hip: mean diff -5.8. p <0.001, knee: mean diff 9.6, p < 0.001, ankle: mean diff 32.4, p < 0.001). Midstance (hip: mean diff 11.06, p <0.001, ankle: 31.4, p< 0.001). Terminal stance (hip: mean diff 28.3, p< 0.004, ankle: mean diff 31.4, p< 0.001) and Pre-swing (hip: mean diff 16.5, p< 0.001, ankle: mean diff 31.4, p< 0.001). Conclusions: The hip and ankle joints equally share knee kinematic compensations. By acknowledging the complex interactions between the hip, ankle, and knee joints, healthcare providers can develop more comprehensive and effective treatment plans for individuals with knee OA.

Mechanisms of gait speed changes in middle-aged adults: Simultaneous analysis of magnitude and temporal effects

BackgroundMiddle-aged adults represent the transition between younger and older adults, where some of the characteristic gait differences due to aging begins to surface. However, the gait characteristics of middle-aged adults across the whole gait cycle remains an understudied topic. As speed is a sensitive indicator of health, characterizing the effects of speed on the gait of middle-aged adults and differentiating it from the response of young adults will provide insights into the effects of aging on gait speed modulation mechanisms. Research questionWhat are the mechanisms of gait speed changes that are employed by middle-aged adults, and how are they different from younger adults? MethodsA cohort of healthy young and middle-aged adults completed 60 second trials at three different speeds. Joint kinematics, kinetics, and surface electromyography data were analyzed and compared between the speed levels and age groups. Statistical Parametric Mapping along with a nonlinear curve registration algorithm was used to simultaneously assess the changes in both magnitude and timing of different metrics. ResultsWhen compared to the younger cohort, the middle-aged cohort had significantly lower ankle range of motion, dorsiflexion moment during loading response and plantarflexion moment during push-off. At the knee joint, the middle-aged adults had significantly lower knee flexion moment during stance. At the hip joint, the middle-aged adults had lower extension moment during terminal stance. SignificanceTime-continuous analysis showed that primary differences due to age were related to decreased joint range of motion and joint moment production capability in the middle-aged adults. Faster walking appears a safe method for middle-aged adults to increase joint range of motion and joint moment expression. However, targeted interventions that focus on improving capability are likely also needed. Suggested targets being improving ankle and knee joint moment capability, and increased range of motion at all joints.

Walking stress-induced changes in gait patterns and muscle activity: Patients with lumbar spinal stenosis versus asymptomatic controls

IntroductionPatients with symptomatic lumbar spinal stenosis (sLSS) are often limited in their walking range because of worsening symptoms, which is thought to induce changes in the gait pattern. The aim of this study was to determine whether changes in gait pattern and muscle activity in these patients are elicited by a walking stress and differ from asymptomatic controls. MethodsTwenty patients with sLSS and 19 asymptomatic controls performed a 30-minute walking stress. Gait was assessed using seven inertial sensors and sagittal joint range of motion (ROM) was calculated during different phases of gait. Muscle activation of the gluteus medius, erector spinae and multifidus muscles was measured by surface electromyography (EMG) and integrated EMGs (normalized to the maximum during gait) were calculated. Differences between groups and time points (beginning and end) were assessed using mixed factorial analysis of variance. ResultsPatients had less knee extension ROM in terminal stance, less knee flexion ROM in swing and less overall hip flexion/extension ROM than controls (p ≤ 0.03). There were no functionally relevant changes in these parameters during the walking stress. The integrated EMG was greater in all muscles in patients than in controls and increased in both groups during the walking stress in the paraspinal but not in the gluteus medius muscle. There was no interaction between group and time for any of the parameters. ConclusionDifferences in gait pattern and muscle activity between patients with sLSS and controls are generally present, but are not amplified by a walking stress.

Effect of femoral derotational osteotomy in patients with idiopathic increased femoral anteversion on joint loading and muscular demands.

This study aimed to analyse the effect of the femoral derotational osteotomy (FDRO) on joint kinematics, kinetics, joint and muscle forces, and muscle moments in patients with idiopathic increased femoral anteversion compared with typically developing children (TDC). In this retrospective study, 17 patients (25 limbs, 13.2 ± 2.2 years, femoral anteversion = 49.0° ± 7.1°) were compared to nine TDC (9 limbs, 12.0 ± 3.0 years, femoral anteversion = 18.7° ± 4.1°). Gait analysis was performed 8.5 ± 7.2 months pre-surgery and 17.3 ± 5.5 months post-surgery. Joint angles, moments and forces as well as muscle forces and muscle contributions to joint moments were analysed using statistical parametric mapping. Significant improvements in kinematics (hip rotation, foot progression, knee and hip flexion) were observed pre- to post-FDRO. Joint forces remained unaltered after surgery and did not differ from TDC. Gluteus minimus and deep external rotators muscle forces decreased in mid-stance, while adductor muscle forces increased during stance post-op compared to pre-op. Due to an improved knee extension postoperatively, the rectus femoris muscle force decreased to normal values during mid- and terminal stance. Postoperatively, only the deep external rotator muscle forces differed from TDC. This study showed that FDRO can restore muscle forces and muscle contributions to joint moments in addition to normal gait kinematics, while joint contact forces remain within normative ranges. This knowledge might also apply to other conditions in which pathological femoral anteversion is present.

Stability of osteotomy in minimally invasive hallux valgus surgery with "8" shaped bandage during gait: a finite element analysis.

Hallux valgus, a common foot deformity, often necessitates surgical intervention. This study evaluates the biomechanical alterations in patients post-surgery, focusing on the efficacy of an "8" bandage fixation system to promote optimal recovery. A three-dimensional (3D) model was constructed using CT data from a patient with hallux valgus. A quasi-static finite element analysis (FEA) was conducted in conjunction with gait analysis to evaluate the biomechanical changes at the osteotomy site under "8" shaped bandage fixation following hallux valgus surgery. The effects of the "8" shaped bandage on the stability of the osteotomy site and bone healing were investigated at three load points during the gait cycle. During the Loading Response (LR), Midstance (MSt), and Terminal stance TSt phases, the osteotomy end experienced maximum Von Mises stresses of 0.118, 1.349, and 1.485MPa, respectively. Correspondingly, the maximum principal stresses, all of which were compressive along the Z-axis, were 0.11662N, 1.39266N, and 1.46762N, respectively. Additionally, these phases showed a maximum relative total displacement of 0.848mm and a maximum relative shear displacement of 0.872mm. During the stance phase, the osteotomy end of the first metatarsal is predominantly subjected to compressive stress, with the relative displacement within the safe range to promote healing. The application of an "8" bandage for external fixation after surgery can maintain the dynamic stability of osteotomy sites post-minimally invasive hallux valgus correction during the gait cycle, thereby promoting the healing of the osteotomy ends.

Females with hip pain walk with altered kinematics at peaks and throughout the gait cycle

BackgroundFemales with acetabular dysplasia and/or labral tears (hip pain) exhibit altered walking kinematics, with studies reporting mixed results in sagittal and frontal planes compared to pain-free controls, often conducting only discrete analyses and warranting further investigation. The objective of this study was to investigate discrete and continuous hip and pelvic kinematics between females with and without hip pain in two walking conditions. MethodsWe collected kinematic walking data from 69 females (35 with hip pain, 34 controls) using motion capture and an instrumented treadmill in two conditions: preferred and fast (125% preferred). We used a general linear model and one-dimensional statistical parametric mapping to conduct discrete and continuous analyses comparing kinematics between groups, with and without adjustment for gait speed. FindingsThe hip pain group walked with reduced peak hip extension (Preferred: P = .046, Cohen's d = 0.41; Fast: P = .028, d = 0.48) and greater peak anterior pelvic tilt (Preferred: P = .011, d = 0.57; Fast: P = .012, d = 0.58) compared to controls. From continuous analyses, the hip pain group walked with reduced hip extension during terminal stance (Fast: P = .040), greater anterior pelvic tilt throughout (Preferred: P = .007; Fast: P = .004), and greater contralateral pelvic drop (Preferred: P = .045) during midstance. Adjusting for speed slightly affected p-values, but significance was retained for all prior variables except pelvic drop. InterpretationKinematic differences between individuals with and without hip pain may provide insight into potential predisposing factors for hip pathology and/or compensations for pain or pathological processes. This work furthers understanding of altered movement patterns in individuals with hip pain and may inform physical therapy treatments.

The effect of including a mobile arch, toe joint, and joint coupling on predictive neuromuscular simulations of human walking

Predictive neuromuscular simulations are a powerful tool for studying the biomechanics of human walking, and deriving design criteria for technical devices like prostheses or biorobots. Good agreement between simulation and human data is essential for transferability to the real world. The human foot is often modeled with a single rigid element, but knowledge of how the foot model affects gait prediction is limited. Standardized procedures for selecting appropriate foot models are lacking. We performed 2D predictive neuromuscular simulations with six different foot models of increasing complexity to answer two questions: What is the effect of a mobile arch, a toe joint, and the coupling of toe and arch motion through the plantar fascia on gait prediction? and How much of the foot’s anatomy do we need to model to predict sagittal plane walking kinematics and kinetics in good agreement with human data? We found that the foot model had a significant impact on ankle kinematics during terminal stance, push-off, and toe and arch kinematics. When focusing only on hip and knee kinematics, rigid foot models are sufficient. We hope our findings will help guide the community in modeling the human foot according to specific research goals and improve neuromuscular simulation accuracy.

Comparative assessment of heel rise detection for consistent gait phase separation

BackgroundAccurate identification of gait events is crucial to reliable gait analysis. Heel rise, a key event marking the transition from mid-stance to terminal stance, poses challenges in precise detection due to its gradual nature. This leads to variability in accuracy across studies utilizing diverse measuring techniques. Research questionHow do different HR detection methods compare when assessed against the underlying heel motion pattern and visual detection across varying speed, footwear conditions, and individuals? MethodsLeveraging data from over 10,000 strides in diverse scenarios with 15 healthy subjects, we evaluated methods based on measurements from optical motion capture (OMC), force plates, and shank-mounted inertial measurement units (IMUs). The evaluation of these methods included an assessment of their precision and consistency with the heel marker's motion pattern and agreement with visually detected heel rise. ResultsOMC-based heel rise detection methods, utilizing the heel marker's vertical acceleration and jerk, consistently identified the same point in the heel motion pattern, outperforming velocity-based methods and our new position-based method resembling traditional footswitch-based heel rise detection. Variability in velocity and position-based methods derives from subtle heel rise variations after mid-stance, exhibiting individual differences. Our proposed IMU-based methods show promise by closely matching OMC-based accuracy. SignificanceThe results have significant implications for gait analysis, providing insights into heel rise event detection's complexities. Accurate HR identification is crucial for gait phase separation, and our findings, especially with the robust heel marker's jerk-based method, enhance precision and consistency across walking conditions. Moreover, our successful development and validation of IMU-based algorithm offer cost-effective and mobile alternative for HR detection, expanding their potential use in comprehensive gait analysis.

Analysis of windlass mechanism according to one walking cycle.

[Purpose] This study aimed to calculate the windlass mechanism in one walking cycle (WC) using the medial longitudinal arch (MLA) height and compare its mechanism with joint moments, angles, and center of gravity movement. [Participants and Methods] The study analyzed the gait of 20 healthy adults (14 males, six females) using a three-dimensional motion analyzer to calculate several parameters. [Results] In the terminal stance, the MLA height reached 20.6 ± 6.0 mm (minimum value) at 49% WC. Simultaneously, the ankle dorsiflexion angle, ankle internal plantarflexion moment, and forward shift of the center of gravity reached the maximum values. At 62% WC, the MLA height was 26.8 ± 4.8 mm and reached maximum during the stance phase, indicating a windlass mechanism. Additionally, the MLA height was 61.7 ± 22.7 mm at 69% WC, indicating an MLA spiking phenomenon. [Conclusion] The MLA height was lowest at 49% WC due to reverse windlass mechanism. Although the windlass mechanism was activated at 62% WC, it was functionally equivalent to the swing phase. Push-off was impossible during the swing phase. At 69% WC, the swing phase showed a second windlass mechanism.

Effects of Articulated & Static Ankle Foot Orthotics on Gait Kinematics: Foot Drop Patients Perspective

Foot drop is a common occurrence following stroke. Ankle foot orthotics (AFO) are used to correct drop foot deformity with several AFOs available to choose from. Literature suggests research on the impact of articulated AFO on gait. Objective: To determine the impact of static/ rigid and articulated AFO on gait kinematics in foot drop cases. Methods: This cross-sectional study involved 100 unilateral drop foot cases from the PIPOS Rehabilitation Services Program from September 2019 to February 2020. The sample included both genders aged 2-15 years. Gait Lab data were used to compare the results while wearing static AFO and articulated AFO and analyzed using SPSS version 21. T-test was used to see difference between groups with p-value <0.05 considered significant. Results: Articulated AFO is significantly (p<0.001) better than rigid AFO in terms of step length, stride time, and cadence. Articulated AFO is significantly better at initial contact (p<0.001), mid stance (Hip p=0.006, Knee & ankle p<0.001) and terminal stance (p<0.001) than rigid AFO. For Initial Swing, there was a significant (p<0001) difference between AFOs for extension at knee and ankle joint. At mid-swing articulated AFO provided significantly (p<0.001) better flexion at hip and knee joint. At terminal swing articulated AFO provided significantly (p<0.001) better flexion at the hip and required extension at the knee. Conclusions: This study identified Articulated AFO was superior to rigid AFO in improving functional mobility and gait consistency & lowering the risk of falling. Articulated AFOs were significantly better in terms of step length, stride time, and cadence.

Distal femoral osteotomy and patellar tendon advancement for the treatment of crouch gait in patients with bilateral spastic cerebral palsy

BackgroundCrouch gait, or flexed knee gait, represents a common gait pattern in patients with spastic bilateral cerebral palsy (CP). Distal femoral extension and/or shortening osteotomy (DFEO/DFSO) and patellar tendon advancement (PTA) can be considered as viable options when knee flexion contractures are involved. Better outcomes have been reported after a combination of both, independently of the presence of knee extensor lag. In this study, we evaluated the clinical and kinematic outcomes of these procedures. Patients and methodsWe reviewed a cohort of 52 limbs (28 patients) who were treated for crouch gait by DFEO/DFSO alone (group 1, n = 15) or DFEO/DFSO + PTA (group 2, n = 37) as a part of single event multilevel surgery (SEMLS). The mean age at surgery was 14 years, and the mean follow-up time was 18 months. The physical examination data and three-dimensional standardized gait analysis were collected and analyzed before the surgery and postoperatively. ResultsOverall knee range of motion improved in all limbs. The knee flexion decreased significantly in both groups at initial, mid, and terminal stance. Hip flexion significantly decreased in mid-stance for limbs in group 2. Both clinical and gait parameters were most improved in limbs who underwent DFEO/DFSO + PTA. Increased pelvic tilt was observed in both groups after surgery. ConclusionAlthough DFEO/DFSO alone was successful in correcting knee flexion contractures, PTA has helped to improve knee extensor lag and knee extension during gait. Level of evidenceTherapeutic level IV

Analysis of windlass mechanism according to one walking cycle.

[Purpose] This study aimed to calculate the windlass mechanism in one walking cycle (WC) using the medial longitudinal arch (MLA) height and compare its mechanism with joint moments, angles, and center of gravity movement. [Participants and Methods] The study analyzed the gait of 20 healthy adults (14 males, six females) using a three-dimensional motion analyzer to calculate several parameters. [Results] In the terminal stance, the MLA height reached 20.6 ± 6.0 mm (minimum value) at 49% WC. Simultaneously, the ankle dorsiflexion angle, ankle internal plantarflexion moment, and forward shift of the center of gravity reached the maximum values. At 62% WC, the MLA height was 26.8 ± 4.8 mm and reached maximum during the stance phase, indicating a windlass mechanism. Additionally, the MLA height was 61.7 ± 22.7 mm at 69% WC, indicating an MLA spiking phenomenon. [Conclusion] The MLA height was lowest at 49% WC due to reverse windlass mechanism. Although the windlass mechanism was activated at 62% WC, it was functionally equivalent to the swing phase. Push-off was impossible during the swing phase. At 69% WC, the swing phase showed a second windlass mechanism.

Classification of chronic ankle instability using machine learning technique based on ankle kinematics during heel rise in delivery workers.

Ankle injuries in delivery workers (DWs) are often caused by trips, and high recurrence rates of ankle sprains are related to chronic ankle instability (CAI). Heel rise requires joint angles and moments similar to those of the terminal stance phase of walking that the foot supinates. Thus, our study aimed to develop, determine, and compare the predictive performance of statistical machine learning models to classify DWs with and without CAI using ankle kinematics during heel rise. In total, 203 DWs were screened for eligibility. Seven predictors were included in our study (age, work duration, body mass index, calcaneal stance position angle [CSPA] in the initial and terminal positions during heel rise, calcaneal movement during heel rise [CMHR], and plantar flexion angle during heel rise). Six machine learning algorithms, including logistic regression, decision tree, AdaBoost, Extreme Gradient boosting machines, random forest, and support vector machine, were trained. The random forest model (area under the curve [AUC], 0.967 [excellent]; F1, 0.889; accuracy, 0.925) confirmed the best predictive performance in the test datasets among the six machine learning models. For Shapley Additive Explanations, old age, low CMHR, high CSPA in the initial position, high PFA, long work duration, low CSPA in the terminal position, and high body mass index were the most important predictors of CAI in the random forest model. Ankle kinematics during heel rise can be considered in the classification of DWs with and without CAI.

Vertical Ground Reaction Forces in Parkinson's Disease: A Speed-Matched Comparative Analysis with Healthy Subjects.

This study aimed to investigate and compare the vertical Ground Reaction Forces (vGRFs) of patients with Parkinson's Disease (PwPD) and healthy subjects (HS) when the confounding effect of walking speed was absent. Therefore, eighteen PwPD and eighteen age- and linear walking speed-matched HS were recruited. Using plantar pressure insoles, participants walked along linear and curvilinear paths at self-selected speeds. Interestingly, PwPD exhibited similar walking speed to HS during curvilinear trajectories (p = 0.48) and similar vGRF during both linear and curvilinear paths. In both groups, vGRF at initial contact and terminal stance was higher during linear walking, while vGRF at mid-stance was higher in curvilinear trajectories. Similarly, the time to peak vGRF at each phase showed no significant group differences. The vGRF timing variability was different between the two groups, particularly at terminal stance (p < 0.001). In conclusion, PwPD and HS showed similar modifications in vGRF and a similar reduction in gait speed during curvilinear paths when matched for linear walking speed. This emphasized the importance of considering walking speed when assessing gait dynamics in PwPD. This study also suggests the possibility of the variability of specific temporal measures in differentiating the gait patterns of PwPD versus those of HS, even in the early stages of the disease.

Lower-limb joint quasi-stiffness in the frontal and sagittal planes during walking at different step widths

Quasi-stiffness describes the intersegmental joint moment–angle relationship throughout the progression of a task. Previous work has explored sagittal-plane ankle quasi-stiffness and its application for the development of powered lower-limb assistive devices. However, frontal-plane quasi-stiffness remains largely unexplored but has important implications for the development of exoskeletons since clinical populations often walk with wider steps and rely on frontal-plane balance recovery strategies at the hip and ankle. This study aimed to characterize frontal-plane hip and ankle quasi-stiffness during walking and determine how step width affects quasi-stiffness in both the frontal and sagittal planes. Kinematic and kinetic data were collected and quasi-stiffness values computed for healthy young adults (n = 15) during treadmill walking across a range of step widths. We identified specific subphases of the gait cycle that exhibit linear and quadratic frontal-plane quasi-stiffness approximations for the hip and ankle, respectively. In addition, we found that at wider step widths, sagittal-plane ankle quasi-stiffness increased during early stance (∼12–35% gait cycle), sagittal-plane hip quasi-stiffness decreased in late stance (∼40–55% gait cycle) and frontal-plane hip quasi-stiffness decreased during terminal stance (∼48–65% gait cycle). These results provide a framework for further exploration of frontal-plane quasi-stiffness, lend insight into how quasi-stiffness may relate to balance control at various step widths, and motivate the development of stiffness-modulating assistive devices to improve balance related outcomes.

The knee kinematic patterns and associated factors in healthy Thai adults

BackgroundReference values for normal knee kinematics were limited in Asian population and were influenced by race and other factors. This study was aimed to establish the reference values and identify the factors associated with knee kinematics in healthy Thai adults, aged 18–40 years.MethodsA retrospective cohort study was conducted between 2016 and 2020. Healthy Thai adults aged 18–40 years old with body mass index (BMI) between 18.5 and 24.9 kg/m2 were included. All eligible participants were attached with reflective markers. Their walking was captured by 8-digital cameras, and assessed by motion analysis software. The primary outcomes were average knee kinematic data (degrees) in three dimensional planes as valgus-varus, flexion-extension, and internal-external rotation. Paired t-test and multiple linear regression were applied to compare the outcomes and to determine their associated factors.ResultsNinety-eight participants (60 females and 38 males) were included with mean age 28.5 ± 5.4 years, and BMI 21.1 ± 2.0 kg/m2. Knee kinematics showed slight adduction during the swing phase, flexion during the stance phase, and obvious external rotation throughout the gait cycle, with a peak of 30–31 degrees during mid-swing. Right knee was significantly more adducted, flexed and externally rotated than the left side, particularly at mid-stance (P = 0.047, 0.017, and < 0.001, respectively). Females had more knee abduction, flexion and external rotation than males. Age, sex, and BMI were significantly correlated with knee abduction at terminal stance (correlation coefficient − 0.12, 95% confidence interval (CI) -0.23, -0.01; -1.37, 95%CI -2.54, -0.20; and − 0.32, 95%CI -0.61, -0.39, respectively), and rotation at mid-swing (correlation coefficient − 0.36, 95%CI -0.69, -0.02; -7.37, 95%CI -10.82, -3.92; and 0.89, 95%CI 0.01, 1.78, respectively).ConclusionKnee kinematics demonstrates external tibial rotation throughout the gait cycle, significant side differences, and are associated with age, sex, and BMI. Reference values from this study will be useful for functional gait assessment in healthy Thais. However, further comprehensive knee kinetic study including spatio-temporal parameter is recommended.

Management of severe congenital femoral deficiency: Does surgical intervention enhance prosthetic function?

The purpose of this study was to evaluate prosthetic outcome in patients with severe congenital femoral deficiency and the potential benefits of surgical intervention on prosthetic fitting and gait. A retrospective review identified 26 active case records with a proximal femoral focal deficiency using a prosthesis. Validated outcome measures evaluated comfort, function, and prosthetic use and quality-of-life assessment. Outcome compared age groups and surgical intervention. Gait analysis performed in 7 patients further evaluated hip and knee function. Eleven male patients and 15 female patients, including 13 children (mean age 10 years, range 5-16) and 13 adults (mean age 36 years, range 23-63) were evaluated. Better prosthetic function and PedsQL scores were recorded in the pediatric group. There was a trend for better scores after surgery. Gait analysis demonstrated reduced hip extension compensated by knee flexion in 3 patients, 2 patients had hip extension with near normal kinematics, 1 untreated patient walked with an unsteady gait, and the remaining walked well using an ischial-bearing prosthesis with pelvic compensatory movements. The management strategy in severe proximal femoral focal deficiency remains a major challenge. Hip reconstruction seems to improve functional scores. Overall, the scores seem to decline into adulthood but not significantly. Gait analysis before further surgical intervention is recommended because compensatory knee flexion may improve step length in terminal stance. Limited numbers, with short follow-up, prevents clear guidance on the benefit of surgery.

Muscle dynamics analysis by clustered categories during jogging in patients with anterior cruciate ligament deficiency

BackgroundPatients with anterior cruciate ligament (ACL) deficiency (ACLD) tend to have altered lower extremity dynamics. Little is known about the changes in dynamic function and activation during jogging in patients with ACLD.MethodsTwenty patients with an injured ACL before ACL reconstruction (ACLD group) and nine healthy male volunteers (control group) were recruited. Each volunteer repeated the jogging experiment five times. Based on the experimental data measured, a musculoskeletal multibody dynamics model was employed to simulate the tibiofemoral joint dynamics during jogging. Eighteen muscles were used for analysis. The obtained dynamics data were used for clustering and curve difference analysis.ResultsThe 18 muscles studied were divided into 3 categories. All the quadriceps, the soleus, the gastrocnemius, and the popliteus were classified as label 1. All the hamstrings were classified as label 2, and the sartorius muscles were classified as label 3. Among them, the classification of the short head of the biceps femoris was significantly different between the two groups (P < 0.001). The force curves of all 18 muscles and the between-group differences were studied according to clustered categories. Most muscle force in label 1 was approaching zero in the terminal stance phase, which was significantly lower than that in the control group (P < 0.05). The muscle force in label 2 had areas with significant differences in the stance phase. Muscle force in label 3 was significantly lower than that in the control group in the pre-swing phase.ConclusionsThis study showed that there are various changes of muscle function and activation in patients with ACLD. Through clustering and curve analysis, the joint reactions and changes of different muscle forces in the gait cycle between the ACLD and control groups could be further clarified.

The topographical attenuation of cutaneous input is modulated at the ankle joint during gait.

The attenuation of sensory inputs via various methods has been demonstrated to impair balance control and alter locomotor behavior during human walking; however, the effects of attenuating foot sole sensation under distinct areas of the foot sole on lower extremity motor output remains poorly understood. Thus, the purpose of this study was to attenuate cutaneous feedback via regional hypothermia under five different areas of the foot sole and investigate the resultant modulation of kinematic and muscle activity during level walking. Electromyography from eight lower leg muscles, kinematics, and location of center of pressure was recorded from 48 healthy young adults completing walking trials with normal and reduced cutaneous sensation from bilateral foot soles. The results of this study highlight the modulatory response of the tibialis anterior in terminal stance (propulsion and toe-off) and medial gastrocnemius muscle throughout the entire stance phase of gait. The topographical organization of foot sole skin in response to the attenuation of cutaneous feedback from different areas of the foot sole significantly modified locomotor activity. Furthermore, the locomotor response to cutaneous attenuation under the same regions that we previously facilitated with tactile feedback do not oppose each other, suggesting different physiological changes to foot sole skin generate unique gait behaviors.

Effects of McConnell and Kinesio taping on kinematic variables during stair descent in patients with patellofemoral pain syndrome.

Studies regarding effects of therapeutic tapings when patients with patellofemoral pain syndrome (PFPS) descend stairs are limited. The purpose of this study was to investigate the effect of McConnell taping (MT) and Kinesio taping (KT) on kinematic variables when patients with PFPS descend stairs. Fifty PFPS patients were randomly assigned to either the MT group or the KT group. Pain and lower extremities joint angles were measured while descending stairs before and after the intervention. All outcomes measured were analyzed using either paired t tests or independent t tests to compare the difference within or between groups, respectively. There was a statistically significant difference in both groups in anterior knee pain scale score (p< 0.05). As a result of analysis of lower extremities joint angles at initial contact, loading response, and terminal stance, there were statistically significant within-group differences in hip, knee flexion, abduction and lateral rotation angles in both groups (p< 0.05). There were statistically significant within-group differences in hip flexion, knee flexion, and dorsiflexion angles in pre-swing (p< 0.05). There was a statistically significant difference between the groups in the following events: (1) knee lateral rotation angle at initial contact; (2) hip flexion angle at loading response; (3) and hip flexion at terminal stance angle (p< 0.05). MT and KT were effective in lowering knee pain and improving lower extremities joint angle when patients with PFPS descend stairs. In the comparison between the groups, the MT group showed significantly reduced anterior knee pain and increased range of motion of the lower extremities joint compared to the KT group.