Whole body coordination and knee movement control during five rehabilitation exercises

Knee rehabilitation exercises to improve motor control, target movement fluency and displacement variability. Although knee movement in the frontal plane during exercise is routinely assessed in clinical practice, optimal knee control remains poorly understood. In this study, twenty-nine healthy participants (height: 1.73±0.11 m, mass: 73.5±16.4 kg, age: 28.0±6.9 years) performed four repetitions of five rehabilitation exercises whilst motion data were collected using the VICON PlugInGait full body marker set. Fluency and displacement variability were calculated for multiple landmarks, including Centre of Mass (CoM) and knee joint centres. Fluency was calculated as the inverse of the average number of times a landmark velocity in the frontal plane crossed zero. Variability was defined as the standard deviation of the frontal plane movement trajectories. CoM fluency and displacement variability were significantly different between tasks (p<0.001). CoM displacement variability was consistently smallest compared to the constituent landmarks (p<0.005). This was interpreted as a whole body strategy of compensatory variability constraining CoM frontal plane movement. Ipsilateral knee fluency (p<0.01) and displacement variability (p<0.001) differed substantially between tasks. The role of the weight-bearing knee seemed dependent on task constraints of the overall movement and balance, as well as constraints specific for knee joint stability

Can different seating aids influence a sitting posture in healthy individuals and does gender matter?

This study determined differences in spinal-pelvic kinematics sitting on (i) mat (ii) block and (iii) novel 10º forward inclined wedge (ButtaflyTM) in a same-subject repeated measures cross-over design in 60 healthy individuals (34 females). Repeated measures ANOVA revealed statistically significant differences between sitting conditions and lumbar and pelvic sagittal angles. Both, the inclined wedge and the block seating aids reduced overall flexion, but the inclined wedge had a greater influence in the lumbar region whilst the block induced the greatest change in the pelvis. This may be relevant for seating aid design personalised to posture type. Statistically significant gender differences were identified in all 3 seating conditions with males adopting more flexed lumbar spine and posteriorly tilted pelvis. Females flexed less in thoracic spine when sitting on an inclined wedge and a block. These statistically significant differences between males and females may provide first explorative direction for bespoke seating aids design

Non-specific chronic low back pain: differences in spinal kinematics in subgroups during functional tasks

Purpose: A multidimensional classification approach suggests that motor control impairment subgroups exist in non-specific chronic low back pain (NSCLBP). Differences in sitting lumbar posture have been identified between two such subgroups [flexion pattern (FP) and active extension pattern (AEP)] and healthy individuals; however, functional spinal movement has not been explored. This study will evaluate whether NSCLBP subgroups exhibit regional spinal kinematic differences, compared to healthy individuals, during functional tasks. Methods: Observational, cross-sectional study design. Spinal kinematics of 50 NSCLBP subjects (27 FP, 23 AEP) and 28 healthy individuals were investigated using 3D motion analysis (Vicon™) during functional tasks [reaching upwards, step down, step up, lifting, and replacing a box, stand-to-sit, sit-to-stand, bending to retrieve (and returning from retrieving) a pen from the floor]. Mean sagittal angle for the total thoracic, total lumbar, upper thoracic, lower thoracic, upper lumbar, and lower lumbar regions between groups was compared. Results: Significant differences were observed in lower thoracic and upper lumbar regions between NSCLBP subgroups during most tasks. Significant differences were observed between the FP and healthy group in the lower thoracic region during stand-to-sit-to-stand tasks and bending (and returning from) to retrieve a pen from the floor. All significant results demonstrated the FP group to operate in comparatively greater flexion. Conclusions: The thoraco-lumbar spine discriminated between FP and AEP, and FP and healthy groups during functional tasks. FP individuals demonstrated more kyphotic thoraco-lumbar postures, which may be pain provocative. No significant differences were observed between AEP and healthy groups, suggesting that alternative mechanisms may occur in AEP

Diabetic foot care within the context of rehabilitation: keeping people with diabetic neuropathy on their feet

Background A large percentage of patients with diabetes mellitus have neuropathy putting them at risk of developing severe foot problems. In diabetic foot care the primary objective is to prevent foot ulceration and avoid loss of limb. The role of physical therapy in diabetic foot care remains insufficiently defined. This narrative review discusses principles of diabetic foot care and implications for rehabilitation. Objectives The objectives are to review: • which aspects of current diabetic foot care are relevant for rehabilitation. • how and where physical therapy expertise can contribute to diabetic foot care. • how physical therapy can safely design an exercise programme when patients have diabetic neuropathy. Major findings The diabetic foot is a complex condition. Current best practice involves care by a multi-disciplinary team. Physical therapy should adhere to key elements of foot ulcer prevention. The effect of reduced balance and mobility resulting from foot ulceration and its treatment indicates a need for bespoke exercise programs. During full weight-bearing exercises protective footwear should be worn at all times. Furthermore, a good understanding of the impact of functional exercises used in rehabilitation with respect to plantar pressure and postural control needs to ensure that exercise prescription is appropriately targeted and safe. Conclusions Physical therapy can make a considerable contribution to overall management of patients with diabetic neuropathy. A tailored exercise programme to improve fitness, strength, range of motion, balance and mobility should be aimed primarily at keeping patients with diabetic neuropathy safely on their feet and improve clinical outcomes

The effect of visual dual-tasking interference on walking in healthy young adults

Background Visual dual-task skills are essential for stable ambulation in everyday life such as walking while reading text. Gait analysis in a virtual environment can provide insight into altered walking performance while visual dual-tasking. Research question How visual dual-tasking including cognitive load of reading text and altered optical flow influences walking speed and stability in healthy adults? Also, is there a relationship between the mediolateral centre of mass(CoM) displacement and mediolateral trunk movement? Methods Nineteen able-bodied young adults performed self-selected walking on a treadmill in a virtual environment under the following three conditions; single-task walking, walking while viewing scrolling lines, and walking while reading text scrolling on the screen. Three-dimensional motion analysis was used to measure the effect of dual-tasking on gait velocity, step length, mediolateral CoM displacement, and mediolateral thorax inclination. Results The effect of visual dual-tasking showed significantly increased walking speed and longer step length compared to single-tasking. The cognitive load of reading text while walking had a significant impact on reduced step length variability and greater mediolateral CoM displacement. This was related to the mediolateral thorax inclination. Significance A visual dual-task influences gait through altered optical flow and a cognitive load effect. Altered optical flow increased walking speed whilst the visual attention to read text affected foot placement and upright trunk posture, together with greater mediolateral CoM displacement. Thus, dual-tasking of reading text in a virtual environment substantially affected walking stability in healthy young people. This paradigm is therefore useful for assessment of walking stability in daily life and in the clinical setting

Increased use of stepping strategy in response to medio-lateral perturbations in the elderly relates to altered reactive tibialis anterior activity

Background The influence of aging on reactive control of balance during walking has been mainly investigated in the sagittal plane, whereas balance control in response to frontal plane perturbations is largely unexplored in the elderly. This is remarkable, given that walking mainly requires active control in the frontal plane. An extensive gait perturbation protocol was used to test whether reactive control of walking balance changes with aging and whether these changes are more pronounced in the frontal than in the sagittal plane. Research question Do alterations in reactive muscle activity cause an age-related shift in stepping strategy in response to perturbations in the frontal and sagittal planes during walking? Method A treadmill-based perturbation protocol imposed frontal and sagittal plane perturbations of different magnitudes during different phases of the gait cycle. Motion capture and electromyography measured the response to the different perturbations in a group of eighteen young and ten older adults. Results Only for a small subset of the perturbations, reactive muscle activity and kinematic strategies differed between young and older subjects. When perturbation magnitude increased, the older adults relied more on a stepping strategy for inward directed frontal plane perturbations and for sagittal plane perturbation just before heelstrike. Tibialis anterior activity increased less in the older compared to the young subjects. Using simulations, we related tibialis anterior activity to backward and outward movement of the center of pressure in the stance foot and confirmed its contribution to the ankle strategy. We concluded that deficient tibialis anterior activity predisposes elderly to use stepping rather than lateral ankle strategies to control balance. Significance Rehabilitation targets for fall prevention in elderly need to also focus on ankle muscle reactivit

Modulation of gluteus medius activity reflects the potential of the muscle to meet the mechanical demands during perturbed walking

Mediolateral stability during walking can be controlled by adjustment of foot placement. Reactive activity of gluteus medius (GM) is modulated during the gait cycle. However, the mechanisms behind the modulation are yet unclear. We measured reactive GM activity and kinematics in response to a mediolateral platform translation during different phases of the gait cycle. Forward simulations of perturbed walking were used to evaluate the isolated effect of the perturbation and the GM response on gait stability. We showed that the potential of GM to adjust lateral foot placement and prevent collisions during swing varies during the gait cycle and explains the observed modulation. The observed increase in stance, swing or combined GM activity causes an outward foot placement and therefore compensates for the loss of stability caused by a perturbation early in the gait cycle. GM activity of the swing leg in response to a platform translation late in the gait cycle counteracts foot placement, but prevents collision of the swing foot with the stance leg. This study provides insights in the neuromechanics of reactive control of gait stability and proposes a novel method to distinguish between the effect of perturbation force and reactive muscle activity on gait stability

Augmented feedback approach to double-leg squat training for patients with knee osteoarthritis: a preliminary study

The aim of this preliminary study was to explore the effects of two types of augmented feedback on the strategy used by healthy participants and patients with knee osteoarthritis (OA) to perform a double-leg squat. Seven patients with knee OA and seven healthy participants performed three sets of eight double-leg squats: one without feedback, one with real-time kinematic feedback and one with real-time kinetic feedback. Kinematic and kinetic outcome measures (peak knee flexion angle, peak knee extensor moment, and symmetry of the support knee moment between the injured and non-injured knees) demonstrate the potential influence of real-time kinetic feedback on the motor strategy used to perform a double-leg squat in both groups. This feedback could be used to develop more efficient and effective motor strategies for squatting in patients with knee OA and further evaluation is warranted

Assessing activity participation in the ACL injured population: a systematic review of activity rating scale measurement properties

Background: Participation is an important factor in assessing both the requirement for and outcome from anterior cruciate ligament reconstruction. Many patient-reported rating scales exist; however, measurement properties have not been well established. Objective: To provide a systematic review to identify currently available activity rating scales for anterior cruciate ligament injured subjects and to evaluate current knowledge of their measurement properties. Methods: Systematic searches of four databases (Medline, AMED, EMBASE, and CINAHL) without date or language restriction, using terms structured around the PICOS system were completed on 1st March 2011. Citation tracking, reference screening and contact with lead authors of key papers completed the search strategy. Studies using participation rating scales were identified to assess frequency of reporting and cited validation. Studies assessing one or more psychometric properties of the identified rating scales were subject to independent data extraction and critical appraisal by two independent authors using published tools. Results: Thirty-one rating scales were identified from 241 outcome studies. Most scales were inadequately developed or validated prior to use. Only three scales (Tegner, CSAS, and Marx) had psychometric analysis in eight studies of mixed quality. Only the Tegner scale has adequate assessment of reliability, validity, and responsiveness. The use of type, intensity, and frequency variables in the identified scales is discussed. Conclusions: The Tegner scale has been adequately validated; however, other rating scales require further validation. A comprehensive comparative analysis of clinical applicability and psychometric testing of existing scales, including clinically useful statistics, is required