Asymmetric Weight Bearing Research Articles

To Compare the Effect of Muscle Energy Technique and Mckenzie Exercises on Pain, range of Motion and Disability among Patients with Sacroiliac Dysfunction

Abstract: Sacroiliac joint dysfunction is a state of malalignment position of pelvic bone. Prolonged asymmetrical weight bearing, produce abnormal load on the lumbar and thoracic spine, which gradually become the source of increasing pain in low back area. Various manual techniques and therapeutic modalities are effective in the treatment of sacroiliac joint dysfunction. However, more sophisticated studies are still required, which justify the result and treatment.

Does visuospatial neglect contribute to standing balance within the first 12 weeks post-stroke? A prospective longitudinal cohort study.

Visuospatial neglect (VSN) has been suggested to limit standing balance improvement post-stroke. However, studies investigating this association longitudinally by means of repeated within-subject measurements early post-stroke are lacking. This prospective longitudinal cohort study evaluates the longitudinal association of egocentric and allocentric VSN severity with 1) standing balance independence and 2) postural control and weight-bearing asymmetry (WBA) during quiet standing, in the first 12 weeks post-stroke. Thirty-six hemiplegic individuals after a first-ever unilateral stroke were evaluated at weeks 3, 5, 8 and 12 post-stroke. Egocentric and allocentric VSN severity were evaluated using the Broken Hearts Test. The standing unperturbed item of the Berg Balance Scale (BBS-s) was used to clinically evaluate standing independence. Posturographic measures included measures of postural control (mediolateral (ML)/anteroposterior (AP) net center-of-pressure velocities (COPvel)) and WBA during quiet standing. A linear mixed model was used to examine longitudinal associations between egocentric and allocentric VSN, and BBS-s, COPvel-ML, COPvel-AP and WBA within the first 12 weeks post-stroke. Egocentric (β = -0.08, 95%CI[-0.15;-0.01], P = .029) and allocentric VSN severity (β = -0.09, 95%CI[-0.15; -0.04], P = .002) were significant independent factors for BBS-s scores in the first 12 weeks post-stroke. Egocentric and allocentric VSN were no significant independent factors for COPvel-ML, COPvel-AP and WBA in the first 12 weeks post-stroke. Allocentric and egocentric VSN severity were significantly associated with decreased standing independence, but not impaired postural control or greater asymmetric weight-bearing, in the early subacute post-stroke phase. This may involve traditional VSN measures being not sensitive enough to detect fine-grained VSN deficits due to a ceiling effect between 5 and 8 weeks post-stroke, once the individual regains standing ability. Future studies may require more sensitive VSN measurements to detect such deficits. Trial registration Clinicaltrials.gov. unique identifier NCT05060458.

Impact of Pelvic Alignment and Balance on Clinical and Community Walking Performance in Patients with Stroke: A Cross-sectional Study

Background: Stroke is global health problem leading to significant mortality and morbidity. Patients with stroke has asymmetrical weight bearing and altered pelvic alignment. Low cardiovascular fitness affects the ability of walking and promote negative effect on overall health. So, the purpose was to analyse the influence of pelvic alignment on balance, and gait in patients with Stroke and its relation with walking performance.

골반 불균형을 동반한 특발성 척추 측만증 청소년의 외발서기 동적 균형훈련의 효과 검증

This study examined the effects of single leg dynamic balance training on cobb"s angle, asymmetrical pelvic angle and gait in adolescent idiopathic scoliosis with pelvic disproportion. We selected 12 subjects who have Cobb"s angle of greater than 10°with pelvic disproportion. Subjects were randomly assigned to spinal stability exercise group(SSEG) 6 or spinal stability exercise and single leg dynamic balance training group(SLDBTG) 6. SSEG was performed spinal stabilization exercise and SLDBTG was performed spinal stabilization exercise and single leg dynamic balance training. We measured pre and post effect of cobb"s angle, asymmetrical pelvic angle and gait. The results showed that the single leg dynamic balance training improved significantly the difference in Cobb"s angle, asymmetric pelvic angle and gait compared to the spinal stability exercise. According to theses results, we verified that single leg dynamic balance training had a considerable effect on asymmetrical weight bearing in adolescent scoliosis. Therefore, this study suggested about how the single leg dynamic balance training will effect asymmetrical pelvic angle and gait in adolescent idiopatic scoliosis.

Bridge-Enhanced Anterior Cruciate Ligament Repair Leads to Greater Limb Asymmetry and Less Cartilage Damage Than Untreated ACL Transection or ACL Reconstruction in the Porcine Model

Background: The extent of posttraumatic osteoarthritis (PTOA) in the porcine anterior cruciate ligament (ACL) transection model is dependent on the surgical treatment selected. In a previous study, animals treated with bridge-enhanced ACL repair using a tissue-engineered implant developed less PTOA than those treated with ACL reconstruction (ACLR). Alterations in gait, including asymmetric weightbearing and shorter stance times, have been noted in clinical studies of subjects with osteoarthritis. Hypothesis: Animals receiving a surgical treatment that results in less PTOA (ie, bridge-enhanced ACL repair) would exhibit fewer longitudinal postoperative gait asymmetries over a 1-year period when compared with treatments that result in greater PTOA (ie, ACLR and ACL transection). Study Design: Controlled laboratory study. Methods: Thirty-six Yucatan minipigs underwent ACL transection and were randomized to receive (1) no further treatment, (2) ACLR, or (3) bridge-enhanced ACL repair. Gait analyses were performed preoperatively, and at 4, 12, 26, and 52 weeks postoperatively. Macroscopic cartilage assessments were performed at 52 weeks. Results: Knees treated with bridge-enhanced ACL repair had less macroscopic damage in the medial tibial plateau than those treated with ACLR or ACL transection (adjusted P = .03 for both comparisons). The knees treated with bridge-enhanced ACL repair had greater asymmetry in hindlimb maximum force and impulse loading at 52 weeks than the knees treated with ACL transection (adjusted P < .05 for both comparisons). Although not significant, there was a trend that knees treated with bridge-enhanced ACL repair had greater asymmetry in hindlimb maximum force and impulse loading (adjusted P < .10 for both comparisons) compared with ACLR. Conclusion: Contrary to our hypothesis, the surgical treatment resulting in less macroscopic cartilage damage (ie, bridge-enhanced ACL repair) exhibited greater asymmetry in load-related gait parameters than the other surgical groups. This finding suggests that increased offloading of the surgical knee may be associated with a slower rate of PTOA development. Clinical Relevance: Less cartilage damage at 52 weeks was found in the surgical group that continued to protect the limb from full body weight during gait. This finding suggests that protection of the knee from maximum stresses may be important in minimizing the development of PTOA in the ACL-injured knee within 1 year.

Visual symptoms, Neck/shoulder problems and associated factors among surgeons performing Minimally Invasive Surgeries (MIS): A comprehensive survey.

Minimally Invasive Surgery (MIS) is demanding on the musculoskeletal and visual systems. Prevalence, severity and association of neck/shoulder problems and visual symptoms were examined among MIS surgeons. The associations of workplace and individual factors with these symptoms independently and combined were also examined. MIS surgeons completed a comprehensive online survey inclusive of 52 questions about individual and workplace physical factors, neck/shoulder problems and visual symptoms. Binary logistic regression models were conducted to determine the associations of the neck/shoulder problems, visual symptoms and combined symptoms with workplace and individual factors. 290 surgeons completed the survey. Neck/shoulder problems and visual symptoms were reported by 31.0% and 29.0%, respectively, 15.5% reported both problems. The prevalence and severity of neck/shoulder problems and visual symptoms were significantly associated (p < 0.001). Several workplace and individual factors were associated with these symptoms (p ≤ 0.05). Several factors in the workplace environment (temperature, asymmetrical weight bearing and forward head movement) and individual (being female and wearing vision correction glasses) were significantly associated with neck/shoulder problems and visual symptoms. Evaluation of different strategies to minimise the strain on the neck/shoulder region and the visual system is required.

A Novel Simplified System to Estimate Lower-Limb Joint Moments during Sit-to-Stand.

To provide effective diagnosis and rehabilitation, the evaluation of joint moments during sit-to-stand is essential. The conventional systems for the evaluation, which use motion capture cameras, are quite accurate. However, the systems are not widely used in clinics due to their high cost, inconvenience, and the fact they require lots of space. To solve these problems, some studies have attempted to use inertial sensors only, but they were still inconvenient and inaccurate with asymmetric weight-bearing. We propose a novel joint moment estimation system that can evaluate both symmetric and asymmetric sit-to-stands. To make a simplified system, the proposal is based on a kinematic model that estimates segment angles using a single inertial sensor attached to the shank and a force plate. The system was evaluated with 16 healthy people through symmetric and asymmetric weight-bearing sit-to-stand. The results showed that the proposed system (1) has good accuracy in estimating joint moments (root mean square error < 0.110 Nm/kg) with high correlation (correlation coefficient > 0.99) and (2) is clinically relevant due to its simplicity and applicability of asymmetric sit-to-stand.

A Monosodium Iodoacetate Osteoarthritis Lameness Model in Growing Pigs.

Simple SummaryOsteoarthritis is a cause of lameness in pigs. It causes pain for affected pigs and reduces profit for the farmer. From an acute problem, it progresses into a chronic condition. To study treatments for osteoarthritis, a model that mimics the functional and structural aspects of osteoarthritis is needed. To induce osteoarthritis, we injected a chemical compound (Monosodium Iodoacetate) into the carpal joint of 10 pigs (treatment group). Ten other pigs were injected with an innocuous substance (control group). We assessed their gait by visual inspection and with a device that measures weight-bearing on each limb. After 68 days, we euthanized the pigs and examined the tissues of injected joints microscopically. We could confirm structural joint changes resembling osteoarthritis in 8 of 10 pigs in the treatment group These pigs also placed less weight on their affected limb compared to the control group on day 3, 14, 28, and 56. Visually, these pigs were only more lame on day 1. Treatment with Monosodium Iodoacetate caused joint changes and lameness resembling those of naturally-occurring osteoarthritis. Although the model needs improvement for use in visual lameness, it enables the study of (drug) intervention on objective movement–pain behavior and structural joint changes.Lameness is a common problem in pigs, causing welfare issues in affected pigs and economic losses for farmers. It is often caused by osteoarthrosis (OA) in its acute or chronic form. We assessed face and construct validity of a potential model for naturally-occurring OA and its progression to chronic OA. Such a model would allow the assessment of possible interventions. Monosodium-iodoacetate (MIA) or isotonic saline was deposited in the intercarpal joint of 20 growing pigs. Functional effects were assessed using subjective (visual lameness scoring) and objective (kinetic gait analysis) techniques at several timepoints. Structural effects were assessed by histopathology at 68 days. Eight out of 10 MIA treated animals had histopathological OA lesions confirmed in the target joint, while for all saline treated animals the target joint was judged to be normal. Pressure mat analysis revealed increased asymmetric weight bearing in these animals compared to the control group on day 3, 14, 28 and 56. Visual scoring only showed a difference between groups on day 1. MIA did not cause prolonged visible lameness, thus face validity for OA under field conditions was not entirely met. Since objective gait parameters showed decreased weightbearing as a behavioral expression of pain, it may be used as a general model for movement-induced pain in pigs.

Weight-bearing perception during standing and sit-to-stand tasks in subacute post-stroke individuals undergoing intensive rehabilitation

It is well known that people with hemiparesis after stroke have asymmetric weight bearing (WB) when standing and during sit-to-stand (STS). However, few studies have quantified the WB perception during these tasks in rehabilitation, which might be an important consideration for therapists. This study assessed WB errors in perception during rehabilitation in subacute post-stroke individuals and identified factors that might explain greater errors in WB perception. Sixteen participants (9 right lesions; 52.6 [±23] days post-stroke) admitted in a stroke unit agreed to participate. The first assessment (admission) was performed when they could stand alone 10 s and rise from sitting, and the second (discharge) a week before discharge. Their physical therapist performed the clinical tests. They were then assessed in the laboratory with force plates to characterize their WB distributions during three trials of standing and STS tasks using two-foot positions (spontaneous and standardised). They were also asked to rate their perceived WB distribution at the lower limbs on a visual analog scale. Multivariate and correlational analyses allowed comparison of real WB and WB perception while standing and rising at admission and discharge, and identification of factors that might influence the errors in WB perception. WB asymmetry was present in the first months after stroke and persisted despite rehabilitation. Overall, WB asymmetry at admission and discharge were not different. The patients were able to identify the side on which the loading was higher but tended to overestimate the WB under the paretic foot. There were no effects of tasks, time of evaluation or foot position on the errors of WB perception. At admission, the mean values of absolute error were 8.23% (7.10) and 8.38% (6.24) for the spontaneous standing and STS tasks, respectively. Paretic lower limb motor function evaluated by Chedoke, and knee extensor strength were associated with errors in WB perception. Therapists could not consider that WB perception is precise in subacute post-stroke individuals. It would be interesting in the future to further explore the size or the threshold of error in WB perception that has an effect on rehabilitation.

Kinetic and kinematic gait analysis in the pelvic limbs of normal and post-hemilaminectomy Dachshunds.

To compare pelvic limb kinetic and kinematic gait parameters between Dachshunds six months following hemilaminectomy for treatment of thoracolumbar disc extrusion (post-hemilaminectomy; PHL) and Dachshunds without history and clinical evidence of spinal cord disease (control; CON). The CON (n = 8) and PHL (n = 6) Dachshunds were recruited for objective gait evaluation. Kinetic data collected included peak vertical force (PVF), stance phase duration and swing phase duration. Kinematic data collected included tarsal, stifle and hip range of motion (ROM) during stance and swing phases of the trot, tail ROM, and horizontal and vertical components of pelvis ROM. No significant differences were identified between tarsal, stifle, hip, and tail ROM between CON and PHL Dachshunds. Although PVF was not significantly different between CON and PHL Dachshunds, PVF varied on average by 14% between the pelvic limbs in PHL Dachshunds (p <0.01). Horizontal and vertical components of pelvic ROM were on average 51% and 36% greater in PHL Dachshunds compared to CON Dachshunds (p = 0.04 and p = 0.02 respectively). Six months after decompressive hemilaminectomy, Dachshunds have abnormal pelvic motion and asymmetric pelvic limb weight bearing. Pelvic sway (ROM) may be a more sensitive indicator of myelopathy than pelvic limb joint ROM and may serve as a useful objective tool to characterize response to treatment in patients with spinal cord disease.

Biofeedback rehabilitation of posture and weightbearing distribution in stroke: a center of foot pressure analysis.

Weight bearing on the paretic lower extremity and transfer of weight from one lower extremity to the other are important goals of stroke rehabilitation. Improvements in these limb loading and weight transfer abilities have been shown to relate to improved performance of many functional activities. Unfortunately, valid and practical clinical measures of paretic lower extremity loading and weight transfer have not been identified. The purpose of this study was to quantitatively assess, through center of foot pressure (CoP) analysis of quiet upright stance control, recovery of paretic limb loading as a measure of weight transfer in early stroke subjects, testing the effectiveness of a targeted rehabilitation intervention based on audiovisual biofeedback. Thirty-seven adults with lower extremity motor impairment following unilateral, non-cerebellar stroke, were Biofeedback rehabilitation of posture and weightbearing distribution in stroke: a center of foot pressure analysis tested twice, at an interval of at least one month post stroke and following rehabilitation intervention aimed at correcting their asymmetrical weight bearing. The intervention was performed with (Study Group, SG) or without (Control Group, CG) a postural audio-visual biofeedback approach. Indices of postural stability and of balance control asymmetry were estimated by acquiring the movements of the CoP during quiet upright stance condition with or without visual input (eyes open, EO and eyes closed, EC). Clinical scales were also administered. Both the CG and the SG subjects showed improved control in upright stance posture as documented by significant improvements in the scale scores and indices of stability during both the EO and the EC condition. Only the SG showed a significantly reduced CoP index of asymmetry. The CoP index of asymmetry, correlating with clinical motor scales, is a valid measure of paretic limb loading during stroke recovery. Postural audio-visual biofeedback represented the more effective approach for reducing weight loading asymmetry of the lower limbs in stroke.

Botulinum Toxin Type A Injection for Spastic Equinovarus Foot in Children with Spastic Cerebral Palsy: Effects on Gait and Foot Pressure Distribution.

PurposeTo investigate the effect of intramuscular Botulinum toxin type A (BoNT-A) injection on gait and dynamic foot pressure distribution in children with spastic cerebral palsy (CP) with dynamic equinovarus foot.Materials and MethodsTwenty-five legs of 25 children with CP were investigated in this study. BoNT-A was injected into the gastrocnemius (GCM) and tibialis posterior (TP) muscles under the guidance of ultrasonography. The effects of the toxin were clinically assessed using the modified Ashworth scale (MAS) and modified Tardieu scale (MTS), and a computerized gait analysis and dynamic foot pressure measurements using the F-scan system were also performed before injection and at 1 and 4 months after injection.ResultsSpasticity of the ankle plantar-flexor in both the MAS and MTS was significantly reduced at both 1 and 4 months after injection. On dynamic foot pressure measurements, the center of pressure index and coronal index, which represent the asymmetrical weight-bearing of the medial and lateral columns of the foot, significantly improved at both 1 and 4 months after injection. The dynamic foot pressure index, total contact area, contact length and hind foot contact width all increased at 1 month after injection, suggesting better heel contact. Ankle kinematic data were significantly improved at both 1 and 4 months after injection, and ankle power generation was significantly increased at 4 months after injection compared to baseline data.ConclusionUsing a computerized gait analysis and foot scan, this study revealed significant benefits of BoNT-A injection into the GCM and TP muscles for dynamic equinovarus foot in children with spastic CP.

Effects of sensory augmentation on postural control and gait symmetry of transfemoral amputees: a case description.

Despite recent advances in leg prosthetics, transfemoral amputees still experience limitations in postural control and gait symmetry. It has been hypothesized that artificial sensory information might improve the integration of the prosthesis into the human sensory-motor control loops and, thus, reduce these limitations. In three transfemoral amputees, we investigated the effect of Electrotactile Moving Sensation for Sensory Augmentation (EMSSA) without training and present preliminary findings. Experimental conditions included standing with open/closed eyes on stable/unstable ground as well as treadmill walking. For standing conditions, spatiotemporal posturographic measures and sample entropy were derived from the center of pressure. For walking conditions, step length and stance duration were calculated. Conditions without feedback showed effects congruent with findings in the literature, e.g., asymmetric weight bearing and step length, and validated the collected data. During standing, with EMSSA a tendency to influence postural control in a negative way was found: Postural control was less effective and less efficient and the prosthetic leg was less involved. Sample entropy tended to decrease, suggesting that EMSSA demanded increased attention. During walking, with EMSSA no persistent positive effect was found. This contrasts the positive subjective assessment and the positive effect on one subject's step length.

Muscle strength does not explain standing ability in children with bilateral spastic cerebral palsy: a cross sectional descriptive study

BackgroundIn bilateral cerebral palsy (CP) muscle strength is considered important for development of gross motor functions, but its influence on standing ability has not been explored. Our aims were to examine muscle strength with respect to the ability to stand with (SwS) or without (SwoS) hand support, asymmetrical weight bearing (WB), and whether the ability to produce strength was influenced by different seated conditions.MethodsIn this cross sectional descriptive study standing posture was recorded with 3D motion analysis, and muscle strength was measured with a hand-held dynamometer, in 25 children with bilateral CP, GMFCS levels II-III, SwS (n = 14, median age 11.4 years), or SwoS, (n = 11, median age 11.4 years). Strength measurements were taken in the hip flexors, knee extensors, dorsiflexors and plantarflexors, in two seated conditions; a chair with arm- and backrests, and a stool.ResultsCompared to SwoS, children SwS stood with a more flexed posture, but presented with equal strength in the hip flexors, dorsiflexors and plantarflexors, and with somewhat more strength in the knee extensors. Despite asymmetric WB during standing, both limbs were equally strong in the two groups. No differences in strength were measured between the two seated conditions.ConclusionsDespite challenges measuring muscle strength in CP, the lower limb muscle strength cannot be considered an explanatory factor for variations in standing in this group of children with bilateral CP. The findings rather strengthen our hypothesis that deficits in the sensory systems could be as determinant for standing as muscle weakness in children with bilateral spastic CP.

Determinants of sit-to-stand tasks in individuals with hemiparesis post stroke: A review

Background and purposeThe ability to rise from a chair to reach a standing position is impaired after stroke. This paper aims to review for the first time the factors that impact the ability to rise from a chair and identify recommendations for post-stroke rehabilitation. MethodsIn order to analyse relevant scientific publications (French and English), the search terms “stroke”, “rehabilitation” and “sit-to-stand” (STS and its variations) were used. The initial literature search identified 122 titles and abstracts for full review and 46 were retained because both the junior and senior researchers agreed that they were aligned with the objectives of this review. Results and conclusionDuring STS, most individuals with hemiparesis able to stand independently presented several changes such as lateral deviation of the trunk towards the unaffected side (ipsilesional side), asymmetrical weight bearing (WB) and asymmetry of knee moment forces. Interestingly, the WB asymmetry was observed even before seat-off, when subjects with hemiparesis still had their thighs in contact with the chair suggesting a planned strategy. Among other interesting results, the time to execute the STS was longer than in controls and influenced by the sensorimotor deficits. A greater risk of falling was observed with a need for more time to stabilize the body during STS and especially during the extension phase. Some rehabilitation interventions may be effective in improving STS duration, WB symmetry and the ability to stand independently with repeated practice (mentally or physically) of STS tasks. However, more research is essential to further investigate effects of specific training protocols and pursue better understanding of this complex and demanding task, particularly for stroke patients who need assistance during this transfer.

English

Introduction: Stroke related hemiparesis also exhibit asymmetry in standing posture and walking. Chronic stroke survivors represent with asymmetric gait pattern due to altered weight distribution. Altered weight distribution of lower limbs that is less weight is taken on affected side, fewer excursions on the weaker side, is seen during static and dynamic balance as well as external perturbation. Objective: To evaluate the effect of Compelled Body Weight Shift Therapy on weight bearing symmetry and balance in post stroke patients. Methods: Total 22 participants were included in the study. All patients received 10mm shoe insole which is to be used on their unaffected side and along with this conventional rehabilitation program were given for 1 hour per day for 2 weeks. Results: There was significant difference in pre-post weight bearing distribution (p<0.001) and balance (p<0.001). There was also significant difference in all the component of Berg Balance Scale (p<0.001). Conclusion: Compelled Body Weight Shift Therapy can be easily administrated in the daily rehabilitation protocol, while treating stroke patients with balance problems due to asymmetrical weight bearing. With more symmetrical weight bearing, balance can be improved for better ambulation and reduced risk of falls.

Effect of compelled body weight shift therapy on weight bearing symmetry and balance in post stroke patients: an experimental pre-post study

Introduction: Stroke related hemiparesis also exhibit asymmetry in standing posture and walking. Chronic stroke survivors represent with asymmetric gait pattern due to altered weight distribution. Altered weight distribution of lower limbs that is less weight is taken on affected side, fewer excursions on the weaker side, is seen during static and dynamic balance as well as external perturbation. Objective: To evaluate the effect of Compelled Body Weight Shift Therapy on weight bearing symmetry and balance in post stroke patients. Methods: Total 22 participants were included in the study. All patients received 10mm shoe insole which is to be used on their unaffected side and along with this conventional rehabilitation program were given for 1 hour per day for 2 weeks. Results: There was significant difference in pre-post weight bearing distribution (p<0.001) and balance (p<0.001). There was also significant difference in all the component of Berg Balance Scale (p<0.001). Conclusion: Compelled Body Weight Shift Therapy can be easily administrated in the daily rehabilitation protocol, while treating stroke patients with balance problems due to asymmetrical weight bearing. With more symmetrical weight bearing, balance can be improved for better ambulation and reduced risk of falls.

Comparison of Buttock Pressure and Pelvic Tilting Angle During Typing in Subjects With and Without Unilateral Low Back Pain

Asymmetric sitting posture may cause asymmetric buttock pressure and unilateral low back pain (LBP). The purpose of this study was to compare the differences of buttock pressure between both sides, and pelvic angle (sagittal and coronal planes) during typing in a sitting position on a pressure mat (Baltube) in individuals with and without unilateral LBP. Ten subjects with unilateral LBP and ten subjects without unilateral LBP were recruited for this study. Buttock pressure was measured using a pressure mat and pelvic angles were measured using a palpation meter. The subjects performed typing in a sitting posture for 30 minutes. Pressure data were collected and averaged at initial term (from start to first minutes) and final term (last minutes of 30 minutes). Angles of pelvic tilting were measured after 30 minutes typing. Pressure asymmetry values (difference in pressure between both sides) were calculated at the initial and final terms. A two-way analysis of variance was used to compare the differences between the initial and final pressure asymmetry values in subjects with and without unilateral LBP. An independent t-test was applied to compare the pelvic tilt angles between the two groups. To compare the change of pressure from the initial term to the final term between the symptomatic and asymptomatic sides in the unilateral LBP group, a paired t-test was applied. In the unilateral LBP group, the pressure asymmetric value at the final term was significantly greater than that of the initial term (p<.05). The angle of pelvic tilting in coronal plane was significantly greater in the unilateral back pain group compared to the without unilateral LBP group (p<.05), however, there was no significant difference in the angle of pelvic tilting in the sagittal plane between the two groups (p>.05). In the unilateral LBP group, the change of pressure from the initial term to the final term was significantly less in the symptomatic side (-6.90 mmHg) than the asymptomatic side (5.10 mmHg). This asymmetric sitting posture may contribute to unilateral LBP in the sitting position. Further studies are needed to determine if asymmetric weight bearing in sitting causes unilateral LBP or if unilateral back pain causes asymmetric weight bearing, and if the correction of asymmetric weight bearing in sitting can reduce unilateral LBP.

Kinetic and kinematic evaluation of compensatory movements of the head, pelvis and thoracolumbar spine associated with asymmetric weight bearing of the pelvic limbs in trotting dogs.

To determine ground reaction forces, head and pelvis vertical motion (HVM and PVM, respectively), and thoraco-lumbar lateral angular motion (LAM) of the spine using kinematic gait analysis in dogs with mild asymmetric weight-bearing of the pelvic limbs while trotting. Twenty-seven hound-type dogs were fitted with reflective markers placed on the sagittal crest of the skull, the ischiatic tuberosity, and thoracolumbar spine of dogs to track motion while trotting. Kinetic and kinematic data were used to characterize asymmetry between the left and right pelvic limbs, and to describe HVM, PVM and thoraco-lumbar LAM. Maximum and minimum position and total motion values were determined for each measured variable. Dogs with asymmetric weight bearing of the pelvic limbs had greater PVM on the side with a greater peak vertical force (PVF), and greater thoraco-lumbar LAM toward the side with a lower PVF while trotting. No differences in mean HVM were detected, and there were no significant correlations between the magnitude of HVM, PVM and thoraco-lumbar LAM and the degree of asymmetric weight bearing. Dogs with subtle asymmetric weight bearing of a pelvic limb had patterns of body motion that may be useful in identifying subtle lameness in dogs; greater PVM on the side with greater weight bearing and greater thoraco-lumbar LAM toward the side with less weight bearing while trotting. Description of these compensatory movements is valuable when evaluating dogs with subtle weight bearing asymmetry in the pelvic limbs and may improve the sensitivity of lameness detection during subjective clinical lameness examination.

A hippotherapy simulator is effective to shift weight bearing toward the affected side during gait in patients with stroke

We investigated whether a hippotherapy simulator has influence on symmetric body weight bearing during gait in patients with stroke. Stroke patients were divided into a control group (n = 10) that received conventional rehabilitation for 60 min/day, 5 times/week for 4 weeks and an experimental group (n = 10) that used a hippotherapy simulator for 15 min/day, 5 times/week for 4 weeks after conventional rehabilitation for 45 min/day. Temporospatial gait assessed using OptoGait and trunk muscles (abdominis and erector spinae on affected side) activity evaluated using surface electromyography during sit-to-stand and gait. Prior to starting the experiment, pre-testing was performed. At the end of the 4-week intervention, we performed post-testing. Activation of the erector spinae in the experimental group was significantly increased compared to that in the control group (p < 0.01), whereas activation of the rectus abdominis decreased during sit-to-stand. Of the gait parameters, load response, single support, total double support, and pre-swing showed significant changes in the experimental group with a hippotherapy simulator compared to control group (p < 0.05). Moreover, activation of the erector spinae and rectus abdominis in gait correlate with changes of gait parameters including load response, single support, total double support, and pre-swing in experimental group. These findings suggest that use of a hippotherapy simulator to patients with stroke can improve asymmetric weight bearing by influencing trunk muscles.