Evaluation of mobility recovery after hip fracture: a scoping review of randomized controlled studies.

Few older adults regain their pre-fracture mobility after a hip fracture. Intervention studies evaluating effects on gait typically use short clinical tests or in-lab parameters that are often limited to gait speed only. Measurements of mobility in daily life settings exist and should be considered to a greater extent than today. Less than half of hip fracture patients regain their pre-fracture mobility. Mobility recovery is closely linked to health status and quality of life, but there is no comprehensive overview of how gait has been evaluated in intervention studies on hip fracture patients. The purpose was to identify what gait parameters have been used in randomized controlled trials to assess intervention effects on older people's mobility recovery after hip fracture. This scoping review is a secondary paper that identified relevant peer-reviewed and grey literature from 11 databases. After abstract and full-text screening, 24 papers from the original review and 8 from an updated search and manual screening were included. Records were eligible if they included gait parameters in RCTs on hip fracture patients. We included 32 papers from 29 trials (2754 unique participants). Gait parameters were primary endpoint in six studies only. Gait was predominantly evaluated as short walking, with gait speed being most frequently studied. Only five studies reported gait parameters from wearable sensors. Evidence on mobility improvement after interventions in hip fracture patients is largely limited to gait speed as assessed in a controlled setting. The transition from traditional clinical and in-lab to out-of-lab gait assessment is needed to assess effects of interventions on mobility recovery after hip fracture at higher granularity in all aspects of patients' lives, so that optimal care pathways can be defined.

The long-term effect of comprehensive geriatric care on gait after hip fracture: the Trondheim Hip Fracture Trial--a randomised controlled trial.

SUMMARY: At present, most hip fracture patients are treated in orthopaedic wards. This study showed that a relatively short hospital intervention based on principles of comprehensive geriatric assessment resulted in safer and more efficient gait as long as 1 year following the fracture as compared to conventional orthopaedic treatment. INTRODUCTION: Hip fracture patients are frail, and the fracture is usually followed by substantial decline in gait function. Few studies have assessed gait characteristics other than gait speed and knowledge about the effect of early intervention on long-term gait outcome is sparse. The purpose of this study was to evaluate the long-term effect of pre- and post-surgery Comprehensive Geriatric Care (CGC) on ability to walk, self-reported mobility and gait characteristics in hip fracture patients. METHODS: Two armed, parallel group randomised controlled trial comparing CGC to conventional Orthopaedic Care (OC) in pre- and early post-surgery phase. Hip fracture patients (n = 397), community-dwelling, age >70 years and able to walk at time of the fracture were included. Spatial and temporal gait characteristics were collected using an instrumented walkway (GAITRite® system) 4 and 12 months post-surgery. RESULTS: Participants who received CGC had significantly higher gait speed, less asymmetry, better gait control and more efficient gait patterns, more participants were able to walk and participants reported better mobility 4 and 12 months following the fracture as compared to participants receiving OC. CONCLUSIONS: Pre- and post-surgery CGC showed an effect on gait as long as 1 year after hip fracture. These findings underscore the importance of targeting the vulnerability of these patients at an early stage to prevent gait decline in the long run. As presently, most hip fracture patients are treated in orthopaedic wards with larger focus on the fracture than on frailty, these results are important to inform new models for hip fracture care.

Bilateral Asymmetry in Upper Extremities Is More Pronounced in Distal Compared to Proximal Joints.

The authors' aim was to compare spatial and temporal accuracy in proximal versus distal joints in upper extremities. Given the morphological differences in corticospinal and corticomotoneuronal projections for proximal and distal muscles, they hypothesized that bilateral asymmetry would be larger for distal than for proximal joints. Twelve participants performed isolated flexion-extension movements with the shoulders and index fingers. Angular range of motion of finger and shoulder movements was kept constant. The results showed significant bilateral asymmetry for both proximal and distal joints for both spatial and temporal accuracy. More importantly, bilateral asymmetry was significantly larger for the index fingers than for the shoulders for both spatial and temporal variables, as hypothesized. These results at the behavioral level pave the way for further studies that combine direct measures of neural activation with behavioral measures to further illuminate the potential link between bilateral communication and laterality effects in motor performance.

Comparison of bilateral force deficit in proximal and distal joints in upper extremities.

Bilateral force deficit refers to the phenomenon that maximal generated force during simultaneous bilateral muscle contractions is lower than the sum of forces generated unilaterally. Based on the notion that neural inhibition is the main source for bilateral force deficit and existing differences in neural inhibiting interhemispheric organization of proximal and distal muscles, we expected differences in bilateral deficit in proximal and distal joints. The aim of the current behavioral experiment was to compare bilateral force deficit in proximal compared to distal upper extremity joints. Ten young adults performed single-joint maximal voluntary contractions in isometric flexions of the shoulder and index finger unilaterally and bilaterally. The results showed a significant absolute bilateral force deficit for both proximal (140.01 ± 86.99 N) and distal muscles (4.64 ± 4.86 N). More importantly, relative bilateral force deficit for shoulder flexion was significantly larger than for index finger flexion, -20.51 ± 7.8% and -5.07 ± 3.84% respectively. The hypothesis of a more pronounced bilateral force deficit for proximal compared to distal muscles was confirmed in our results. Thus, our findings, in combination with the neuroanatomical differences for proximal and distal muscles, make it worthwhile to further explore the hypothesis that the commissural fibers provide differences in interhemispheric inhibitory interactions during bimanual actions for proximal and distal muscles.

Training infant treadmill stepping: the role of individual pattern stability.

In this study, we investigated the responsiveness of a developing neuromotor system to training: When is training effective and when are the effects specific to the training condition? Eight infants, six 3-month-olds and two 7-month-olds, received month-long daily training on either a fast-running treadmill, a slow-running treadmill, or a stationary treadmill. Two additional 3-month-old infants served as controls and received no training. Results showed that training led to an increased number of steps. This improvement was inversely related to initial performance: Training had more effect on infants that initially performed unstable stepping patterns. Furthermore, training facilitated the transition from multiple stepping patterns to more alternate stepping. Again, initial pattern preferences influenced these effects of training and often remained visible throughout training. Infant's responses to training at specific speeds were less clear-cut, but some indications were found that this also depended on their initial performances as well as on the characteristics of training. In general, when initial performances corresponded to the training condition, they were strengthened. When they were different from the training condition, training effects generalized to other speeds. These results suggest that the developing neuromotor system is amenable to training whenever performance is unstable, and that training effects interact with the individual's initially preferred patterns. These results are consistent with a dynamic systems view of motor development.

In defence of discovery learning.

The present paper discusses the influence of different training methods--i.e., knowledge of results, preferred frequency, and the availability of a model--on the learning of a complex motor skill, in this case the learning of slalom ski-type movements on a ski-simulator. Results of three experiments performed on this apparatus showed that, although the training methods used influence the course of learning, none of the methods used was actually superior to discovery learning. It is suggested that discovery learning forces the learner to explore the dynamics of the system in which he or she operates, in an iterative way. Possibilities for cooperative working between prescription and discovery learning are discussed.

A dynamical systems approach to skill acquisition.

This paper argues that the answer to the question, what has to be learned, needs to be established before the question, how is it learned, can be meaningfully addressed. Based on this conviction, some of the limitations of current and past research on skill acquisition are discussed. Motivated by the dynamical systems approach, the question of "what has to be learned" was tackled by setting up a non-linear mathematical model of the task (i.e. learning to make sideways movements on a ski apparatus). On the basis of this model, the phase lag between movements of the platform of the apparatus and the actions of the subject was isolated as an ensemble variable reflecting the timing of the subject in relation to the dynamics of the apparatus. This variable was subsequently used to study "how" the task was learned in a discovery learning experiment, in which predictions stemming from the model were tested and confirmed. Overall, these findings provided support for the hypothesis, formulated by Bernstein (1967), that one of the important effects of practice is learning to make use of reactive forces, thereby reducing the need for active muscular forces. In addition, the data from a previous learning experiment on the ski apparatus--the results of which had been equivocal--were reconsidered. The use of phase lag as a dependent variable provided a resolution of those findings. On the basis of the confirmatory testing of predictions stemming from the model and the clarification of findings from a previous experiment, it is argued that the dynamical systems approach put forward here provides a powerful method for pursuing issues in skill acquisition. Suggestions are made as to how this approach can be used to systematically pursue the questions that arise as a natural outcome of the experimental evidence presented here.

Learning to crawl.

The effects of infants' age, body dimensions, and experience on the development of crawling was examined by observing 28 infants longitudinally, from children's first attempts at crawling until they began walking. Although most infants displayed multiple crawling postures en route to walking, development did not adhere to a strict progression of obligatory, discrete stages. In particular, 15 infants crawled on their bellies prior to crawling on hands and knees, but the other 13 infants skipped the belly-crawling period and proceeded directly to crawling on hands and knees. Duration of experience with earlier forms of crawling predicted the speed and efficiency of later, quite different forms of crawling. Most important, infants who had formerly belly crawled were more proficient crawling on hands and knees than infants who had skipped the belly-crawling period. Transfer could not be explained by differences in infants' age or body dimensions alone. Rather, experience using earlier crawling patterns may have exerted beneficial effects on hands-and-knees crawling by shoring up underlying constituents common to all forms of crawling postures.

Preferred tempo in the learning of a gross cyclical action.

Seventy-five subjects, randomly assigned to one of five training conditions, were required to learn to make large-amplitude, high-tempo, fluent movements on a so-called ski-simulator over a period of four days. Subjects trained under different tempo conditions. In four of the conditions the tempo was prescribed ("preferred", high, low, or increasing), augmented feedback being provided to enable subjects to stay on "target". "Preferred" tempo was based on the weight of the subject and was derived from a regression equation based on previous empirical research. In a fifth condition, subjects trained on "discovery learning" principles, i.e. without the tempo being prescribed. The results obtained on the three parameters (amplitude, frequency, and fluency) during the daily test sessions (in which the tempo was not prescribed) formed the data for the analyses. A learning effect was apparent on all three parameters over the four-day training period. Subjects who trained under the high or the low prescribed tempos, however, were shown to produce significantly smaller amplitude movements than subjects who trained under the other three conditions. Training under the low-tempo condition was also shown to have disadvantageous effects on the parameters tempo and fluency. It was concluded that, for these kinds of action, training at a high or a low tempo--and particularly the latter--has undesirable effects. Such disadvantageous effects, however, were shown to be avoidable if training is begun with the "preferred" tempo of the subject and increased successively by 7% over days.