Influence of ankle plantar flexor muscle architecture and strength on gait in boys with haemophilia in comparison to typically developing children

Altered gait patterns, muscle weakness and atrophy have been reported in young boys with severe haemophilia when compared to unaffected peers. The aim of this study was to determine whether lateral gastrocnemius muscle size and architecture influenced biomechanical walking patterns of boys with haemophilia and if these relationships differed from age‐matched typically developing boys. Biomechanical function of the knee and ankle during level walking, lateral gastrocnemius anatomical cross‐sectional area, thickness, width, fascicle length and pennation angle and ankle plantar flexor muscle strength were recorded in 19 typically developing boys aged 7–12 years and 19 age‐matched haemophilic boys with a history of ankle joint bleeding. Associations between gait, strength and architecture were compared using correlations of peak gait values. Haemophilic boys walked with significantly larger (P < 0.05) ankle dorsi flexion angles and knee flexion moments. The ankle plantar flexor muscles of haemophilic boys were significantly weaker and smaller when compared to typically developing peers. In the typically developing boys there was no apparent association between muscle architecture, strength and walking patterns. In haemophilic boys maximum muscle strength and ACSA normalized torque of the ankle plantar flexors together with the muscle width, thickness, fascicle length and angulation (P < 0.05) were associated with motion at the ankle and peak moments at the knee joint. Muscle strength deficits of the ankle plantar flexors and changes in muscle size and architecture may underpin the key biomechanical alterations in walking patterns of haemophilic boys with a history of ankle joint bleeding.     

高龄脑小血管病患者脑微出血与步态障碍的相关性分析

目的探讨高龄脑小血管病患者脑微出血病灶与步态障碍的关系。方法选择80岁以上军队离退休男性脑小血管病患者232例,通过测量定量步态参数及临床步态量表、脑微出血病灶影像学检查和统计学分析,比较脑微出血病灶数目及部位与步长、步速、步宽等步态特征的相关性。结果脑微出血数目与步长(回归系数=-0.02,P=0.03)、步宽(回归系数=0.21,P=0.04)、Tinetti试验(回归系数=-0.19,P=0.00)及起立行走试验(回归系数=0.02,P=0.02)比较,差异有统计学意义。脑叶和深部微出血灶与步长、步宽呈负相关,与Tinetti试验及站立行走试验的相关性差异有统计学意义(P<0.05,P<0.01)。结论脑微出血作为独立因素和高龄脑小血管病患者的步态障碍有相关性。     

A dance program to improve gait and balance in individuals with chronic stroke: a feasibility study

Background and Objective Despite gains made with rehabilitation, gait and balance remain limited post-stroke. Dance is a fun and motivating activity which has shown benefits in individuals with Parkinson’s disease. The purpose of this article is to investigate the feasibility of a dance program for individuals with chronic stroke.

Methods Pre-post intervention feasibility study where twenty individuals with chronic stroke participated in a dance class twice a week for 10 weeks. Feasibility measures included interest, enrollment, attendance, adverse events, and participant satisfaction. Outcomes of interest were spatiotemporal gait parameters and balance assessed with the MiniBESTest before and after the dance program. Pre and post measures were compared with paired t-tests.

Results Of the 33 individuals approached, 30 (90.9%) were interested in participating; however, scheduling conflicts were a common barrier. Ultimately, 22 individuals consented and 20 individuals completed the dance program without adverse events. The mean age was 62.3 (10.4) years, time post-stroke was 6.4 (6.0) years and National Institutes of Health Stroke Scale score was 3.1 (2.0). Average attendance was 92.5% with 10 classes missed across 8 participants and satisfaction ratings were high (e.g. 17/20 strongly agreed they enjoyed the program). No significant differences in spatiotemporal gait parameters were found; however, MiniBESTest scores significantly increased from 16.5 (6.0) to 18.6 (4.9) (p = 0.0005).

Discussion and Conclusions A dance program is safe and feasible post-stroke. Attendance and satisfaction were high and participants perceived walking and balance benefits. Future work will include a randomized controlled trial.     

Effects of radial tears and partial meniscectomy of lateral meniscus on the knee joint mechanics during the stance phase of the gait cycle—A 3D finite element study

The purpose of the current study was to evaluate influences of radial tears and partial meniscectomy of lateral meniscus on the knee joint mechanics during normal walking by using computational modeling. A 3D geometry of a knee joint of a healthy patient was obtained from our previous study, whereas the data of normal walking were taken from the literature. Cartilage tissue was modeled as a fibril reinforced poroviscoelastic material, whereas meniscal tissue was modeled as a transverse isotropic elastic material. The realistic gait cycle data were implemented into the computational model and the effects of radial tears and partial meniscectemy of lateral meniscus on the knee joint mechanics were simulated. Middle, posterior, and anterior radial tears in lateral meniscus increased stresses by 300%, 430%, and 1530%, respectively, at the ends of tears compared to corresponding areas in the model with intact lateral meniscus. Meniscus tears did not alter stresses and strains at the tibial cartilage surface, whereas partial meniscectomy increased contact pressures, stresses, strains and pore pressures in the tibial cartilage by 50%, 44%, 21%, and 43%, respectively. Increased stresses and strains were observed primarily during the first ～50% of the stance phase of the gait cycle. The present study suggests that anterior radial tear causes the highest risk for the development of total meniscal rupture, whereas partial meniscectomy increases the risk for the development of OA in lateral tibial cartilage. Highest risks for meniscus and cartilage failures are suggested to occur during the loading response and mid‐stance of the gait cycle. In the future, the present modeling may be further developed to offer a clinical tool for aid in decision making of clinical interventions for patients with knee joint injuries. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1208–1217, 2013     

Lower Limb Biomechanics in Individuals With Knee Osteoarthritis Before and After Total Knee Arthroplasty Surgery

We investigated the biomechanical changes that occur in the lower limb following total knee arthroplasty (TKA). Lower limb joint kinematics and kinetics were evaluated in 32 patients before and 12 months following TKA and 28 age-matched controls. Analysis of variance with Bonferroni-adjusted post-hoc tests showed no significant changes in knee joint kinematics and kinetics following TKA despite significant improvements in pain and function. Significant increases in peak ankle plantarflexion and dorsiflexion moments and ankle power generation were observed which may be a compensatory response to impaired knee function to allow sufficient power generation for propulsion. Differences in knee gait parameters may arise as a result of the presence of osteoarthritis and mechanical changes associated with TKA as well as retention of the pre-surgery gait pattern.     

Does the Anterior Approach for THA Provide Closer-To-Normal Lower-Limb Motion?

The purpose of this study was to compare the muscle-sparing anterior approach for total hip arthroplasty to a traditional lateral approach using 3D motion analysis. Kinematics and kinetics of walking were obtained for 40 patients (20 anterior and 20 lateral) and 20 control participants. Participants were assessed six to twelve months postoperatively. It was hypothesized that the anterior group would have closer-to-normal range of motion, moments, and powers than the lateral group. Both surgical groups had gait anomalies, such as significantly lower peak hip abduction moments. It is therefore thought that other variables such as preoperative gait adaptations, trauma from the surgery, or postoperative protection mechanisms for avoiding loading the prosthesis might be more influential factors than surgical approach when determining function after surgery.     

Kinematic patterns for hindlimb obstacle avoidance during sheep locomotion

ABSTRACT

Functional recovery following general nerve reconstruction is often associated with poor results. Comparing to rat and mice experimental studies, there are much fewer investigations on nerve regeneration and repair in the sheep, and there are no studies on this subject using gait analysis in the sheep model as an assessment tool. Additionally, this is the first study evaluating obstacle negotiation and the compensatory strategies that take place at each joint in response to the obstacle during locomotion in the sheep model. This study aims to get kinematic data to serve as a template for an objective assessment of the ankle joint motion in future studies of common peroneal nerve (CP) injury and repair in the ovine model. Our results show that a moderately high obstacle set to 10% of the sheep’s hindlimb length was associated to several spatial and temporal strategies in order to increase hoof height during obstacle negotiating. Sheep efficiently cleared an obstacle by increasing knee, ankle and metatarsophalangeal flexion during swing, whereas the hip joint is not affected. This study establishes the bounds of normal motion in the neurologically intact hindlimb when approached and cleared an obstacle and provides baseline data for further studies of peripheral nerve research in the ovine model.     

Head‐pelvis coupling is increased during turning in patients with Parkinson's disease and freezing of gait

Turning is the most important trigger for freezing of gait (FOG). The aim of this study was to investigate the relationship between impaired head‐pelvis rotation during turning and FOG. Head, trunk, and pelvic rotation were measured at onset and throughout a 180‐degree turn in 13 freezers and 14 nonfreezers (OFF medication). We also studied 14 controls at preferred and slow speed to investigate the influence of turn velocity on axial rotation. Location and duration of FOG episodes were defined during the turn. At turning onset, head rotation preceded thorax and pelvic rotation in all groups, but this craniocaudal sequence disappeared when FOG occurred. Maximum head‐pelvis separation was significantly greater in controls, compared to freezers and nonfreezers (35.4 versus 25.7 and 27.3 degrees; P < 0.01), but this finding was speed dependent. Timing of maximum head‐pelvis separation was delayed in freezers, compared to nonfreezers and controls, irrespective of turn velocity. This delay was correlated with increased neck rigidity (R = 0.62; P = 0.02) and worsened during FOG trials. FOG occurred more often at the end of the turn, when difference in rotation velocity between head and pelvis was greatest. Even after controlling for speed and disease severity, turning in freezers was characterized by delayed head rotation and a closer coupling between head and pelvis, especially in turns where FOG occurred. These changes may be attributed to delayed preparation for the change in walking direction and, as such, contribute to FOG. © 2013 Movement Disorder Society