Motion Analysis of the Upper Extremities During Lofstrand Crutch-Assisted Gait in Children with Orthopaedic Disabilities

Background This paper presents a review of current state-of-the-art dynamic systems for quantifying the kinematics and kinetics of the joints of the upper extremities during Lofstrand crutch-assisted gait. The reviewed systems focus on the rehabilitation of children and adults with myelomeningocele (MM), cerebral palsy (CP), spinal cord injury (SCI), and osteogenesis imperfecta (OI). Forearm crutch systems have evolved from models with single- to multi-sensor hardware systems that can incorporate an increasing number of segments that are in compliance with the standards of the International Society of Biomechanics (ISB). Methods The initial system developed by our group was a single, six-axis, sensor-crutch design with an accompanying ISB-compliant, inverse dynamics model. The model consisted of seven upper body segments and two crutch segments. After thorough validation of the software and hardware, it was tested using nine children with MM. The join dynamics of the shoulder, elbow, and wrist were assessed during reciprocal and swing-through gait. Results The dynamic metrics of the upper extremeties, including the mean, range, and maximum force and moment, were found to be significantly different depending on the gait pattern. Joint forces were found to be the greatest during swing-through gait, with inferior forces reaching 50% of body weight. In order to improve upon the initial system, our group developed a four-sensor crutch system that measures the contributions of the crutch-cuff kinetics. The inverse dynamics model was enhanced by including crutch-cuff and sensor segments that also follow the ISB modeling standards. This system was used to model subjects with CP, SCI, and OI. Maximum joint forces were measured in the subject with CP, while maximum moments were measured in the subject with SCI. The subject with OI presented the smallest joint forces and moments. Discussion These novel model systems may be used to improve the quantification of joint dynamics during Lofstrand crutch-assisted gait. These methods may ultimately improve the identification of the risk factors for joint pathology and subsequent therapeutic planning and rehabilitation paradigms

Muscle mechanical work in walker-assisted locomotion: Instrumentationand modelling for an integrated gait analysis in cerebral palsy

La stima del lavoro meccanico muscolare \ue8 un utile strumento per valutare l'efficienza di un movimento, ma il processo di calcolo presenta ancora molte criticit\ue0 dal punto di vista biomeccanico. Diversi metodi per stimare il lavoro meccanico muscolare durante il cammino sono stati presentati in letteratura, ma nonostante i tentativi fatti per confrontarli, tutti i metodi sono tuttora utilizzati in ambito di ricerca e in ambito clinico. Una pi\uf9 profonda comprensione delle differenze, sia dal punto di vista teorico, che pratico, potrebbe permettere di capire cosa venga effettivamente calcolato da ciascun metodo ed aiutare a fare un uso pi\uf9 appropriato di questa informazione. A questo scopo \ue8 stato validato un modello tridimensionale a corpo completo, consistente in 16 segmenti, utilizzato per raccogliere informazioni cinematiche e dinamiche durante il cammino in ragazzi e bambini sani e in ragazzi e bambini affetti da paralisi cerebrale infantile (CP), camminati a velocit\ue0 spontanea. Lo sviluppo di due maniglie strumentate fissabili sulla struttura di deambulatori pediatrici posteriori ha permesso di misurare cinematica e dinamica dell'arto superiore anche in soggetti con maggiori difficolt\ue0 di deambulazione. Curve di potenza e valori di lavoro meccanico muscolare totale, positivo, negativo o netto, durante cammino normale e durante cammino con deambulatore, sono stati stimati dimostrando che tutti i metodi sono equivalenti quando vengono permessi trasferimenti di energia tra segmenti. Senza possibilit\ue0 di trasferimento di energia, i metodi differiscono tra loro, con differenze dipendenti dal metodo utilizzato e dal movimento studiato. Eccetto alcune criticit\ue0 evidenziate e discusse, l'analisi delle curve di potenza muscolare e dei valori di lavoro meccanico muscolare stimati pu\uf2 fornire utili informazioni sulla funzione locomotoria nel suo complesso, mettendo in luce deficit di propulsione, asimmetrie del cammino, inefficienze di movimento associate ad una ridotta capacit\ue0 di recupero di energia.The estimation of muscle mechanical work can be useful to assess movement efficiency, but it is still a challenging task in biomechanics. Different methods to estimate muscle work during walking have been presented in the literature and, although attempts have been made to investigate differences among them, all methods are still used in research and clinical applications. A deeper understanding of theoretical differences and analogies would allow to know what is exactly computed by each method and help to make a more appropriate use of this information. To this purpose, a 16 segments full-body 3D model was validated and used to collect kinematic and kinetic data from healthy children and cerebral palsy (CP) children walking at self-selected speed. Two instrumented handles fixable on the frame of posterior paediatric walkers were also developed, to measure upper limb kinetics in subjects with more severe walking impairements. Whole-body muscle mechanical power curves and work values, either positive, negative or net, during normal gait and during walker locomotion were obtained, demonstrating that all methods are equivalent when energy transfers between segments are allowed. With no transfers allowed, methods differ among each other, with differences depending on the movements and the methods considered. Apart from some critical issues evidenced and discussed, the analysis of whole-body muscle mechanical power curves and work estimates can provide valuable information on the overall locomotion function, highlighting propulsive deficits, gait asymmetries, movement inefficiencies associated to reduced energy recuperation

Development and Application of 3D Kinematic Methodologies for Biomechanical Modelling in Adaptive Sports and Rehabilitation

Biomechanical analysis is widely used to assess human movement sciences, specifically using three-dimensional motion capture modelling. There are unprecedented opportunities to increase quantitative knowledge of rehabilitation and recreation for disadvantaged population groups. Specifically, 3D models and movement profiles for human gait analysis were generated with emphasis on post-stroke patients, with direct model translation to analyze equivalent measurements while horseback riding in use of the alternative form of rehabilitation, equine assisted activities and therapies (EAAT) or hippotherapy (HPOT). Significant improvements in gait symmetry and velocity were found within an inpatient rehabilitation setting for patients following a stroke, and the developed movement profiles for patients have the potential to address patient recovery timelines. For population groups, such as those following a cerebral incident, alternative forms of rehabilitation like EAAT and HPOT are largely unexplored. Within these studies, relevant muscular activations were found between healthy human gait and horseback riding, supporting the belief that horseback riding can stimulate similar movements within the rider. Even more, there was a strong correlation between the horse’s pelvic rotations, and the responsive joint moments and rotations of the rider. These findings could have greater implications in choosing horses, depending on the desired physical outcome, for EAAT and HPOT purposes. Similar approaches were also used to address another biomechanically disadvantage population, adaptive sport athletes. Utilizing similar methodologies, a novel 3D wheelchair tennis athlete model was created to analyze match-simulation assessments. Significant findings were present in the energy expenditure between two drill assessments. Overall, the quantitative results, coupled with the qualitative assessment chapter, provide a robust assessment of the effects of 3D movement analysis on rehabilitation and adaptive activities

Biomechanical Model of Pediatric Upper Extremity Dynamics During Wheelchair Mobility

Biomechanical analysis has been used by many to evaluate upper extremity (UE) motion during human movement, including during the use of assistive devices such as crutches and walkers. However, few studies have been conducted to examine the upper extremity kinetics during wheelchair mobility, specifically within the pediatric population. In 2000, 90% of wheelchair users (1.5 million people) in the United States were manual wheelchair users, requiring the use of their upper body to maneuver the wheelchair as well as perform other activities of daily living. Among children under the age of 18, the wheelchair was the most used assistive mobility device at 0.12% of the USA population (about 88,000 children). Of these children, 89.9% (79,000) use manual wheelchairs. Associated with the leading causes of assistive mobility device usage in children and adolescents, are severe cases of osteogenesis imperfecta (OI), cerebral palsy (CP), myelomeningocele (MM) and spinal cord injury (SCI). Once confined to a wheelchair, the upper extremities must take over the responsibilities of the lower extremities, including mobility and other activities of daily living. For many individuals who are wheelchair-bound since childhood, pain and other pathological symptoms present by their mid to late 20’s. Due to increased life expectancy and continual wheelchair use, these injuries may cause the user to have reduced, or loss of, independent function as they age, further decreasing quality-of-life. Better knowledge of upper extremity dynamics during wheelchair propulsion can improve understanding of the onset and propagation of UE pathologies. This may lead to improvements in wheelchair prescription, design, training, and long-term/transitional care. Thereby, pathology onset may be slowed or prevented, and quality of life restored. In order to better understand and model the UE joints during wheelchair mobility three main goals must be accomplished: 1. Create an upper extremity kinematic model including: additional segments, more accurate representations of segments and joint locations, consideration of ease of use in the clinical setting with children. 2. Create the corresponding kinetic model to determine the forces and moments occurring at each joint. 3. Implement the model and collect preliminary data from children with UE pathology

Functional movement assessment for individuals with knee osteoarthritis

The relationships between dynamic stability, lower extremity strength, and functional performance are not well-understood for individuals with knee pain due to osteoarthritis. The series of studies presented in this dissertation incorporate the assessment of functional movements for healthy older adults, individuals with symptoms of knee osteoarthritis, and individuals following total knee arthroplasty. The functional activities investigated in these populations included stair descent and sit-to-stand. This research was completed through a combination of kinematic techniques of motion analysis and kinetic assessment using multiple force platforms to evaluate joint moments, center of pressure parameters and weight-bearing asymmetry. The findings can be summarized as follows: 1) Kinetic and kinematic indicators of sit-to-stand movement may be standardized for healthy individuals of various ages without regard to initial positioning; 2) Individuals post-total knee arthroplasty compensate for residual physical deficits by utilizing upper extremity support and altered joint loading to perform sit-to-stand successfully; and 3) Altered joint loading and compensatory weight-bearing asymmetry allows individuals with mild to moderate knee pain to perform sit-to-stand and stair descent while maintaining dynamic stability. Older adults with symptoms of osteoarthritis appear to compensate for physical limitations of reduced joint mobility, strength deficits, and pain by adjusting joint loads and altering patterns for movement

Biomechanical Analysis of Elite Race Walking

The aim of this study was to provide a comprehensive analysis of key biomechanical variables in race walking through the analysis of elite athletes in both competitive and laboratory settings. Video data from two 3CCD camcorders of athletes competing over 10 km (juniors only), 20 km, and 50 km were collected at three international competitions. For the 20 km and 50 km events, multiple recordings were made to identify if kinematic changes occurred. In addition, synchronised high-speed video, electromyography and ground reaction force data were collected of 20 elite race walkers in a laboratory setting and combined to calculate joint moments, power and work. The key discriminants with regard to better performances were long step lengths and high cadences, and the contribution made by flight distance to step length (approximately 13%) was particularly important, regardless of race distance or age category. Step length ratio was a better predictor of optimum step length than absolute values and a ratio of about 70% was found in the fastest athletes. Although reductions in step length and flight distance were a major cause of decreased speed over both 20 km and 50 km, many gait variables did not alter greatly, showing that these elite athletes were able to maintain their techniques despite fatigue. The foot position ahead of the body at initial contact (approximately 20% of stature) need not be detrimental to fast walking if the athlete has the strength to overcome the potentially negative effects; instead, it can be beneficial to increase this distance in achieving a greater step length and could be a key area for women in particular to develop. The hip muscles were the main source of energy generation, with both flexors and extensors doing more positive work than any other muscle group (22.4 ± 7.1 J and 42.3 ± 10.1 J respectively), although the ankle plantarflexors also generated considerable energy before toe-off (16.4 ± 3.8 J). A hip extensor moment that occurred during late swing and early stance helped maintain forward momentum as it reduced the braking peak force and duration of the negative anteroposterior force. The knee had little involvement in energy generation because of its predominant role as a rigid lever during stance, and absorbed considerable energy during swing (–46.4 ± 9.5 J). However, its abnormal movement that was dictated by the race walking rule also had an important role in maintaining contact with the ground and reducing vertical forces so that visible loss of contact was avoided. The study was the first to analyse in such depth the biomechanics of elite male and female race walkers across all competitive distances and its results could be used to develop a technical manual for this Olympic event and greatly impact on coaching practice

Quantitative Evaluation of Geared Manual Wheelchair Mobility in Individuals with Spinal Cord Injury: An Integrative Approach

The purpose of this dissertation is to quantify the effects of using geared wheelchair wheels on upper extremity biomechanics and energy expenditure during functional mobility tasks in individuals with spinal cord injury (SCI). The effects of using geared wheels on hand-rim biomechanics, glenohumeral joint dynamics, and shoulder muscle activity were investigated during manual wheelchair propulsion over tiled and carpeted level-floors and up a ramp in low gear (1.5:1) and standard gear (1:1) conditions. The results for the hand-rim biomechanics indicated that regardless of the terrain, using the geared wheels in the low gear condition significantly decreased the propulsion speed, stroke distance, and hand-rim kinetics, including the peak hand-rim resultant force, propulsive moment, and rate of the rise of the resultant force. The significant decrease in the normalized integrated hand-rim propulsive moment suggests that the low gear condition is less demanding than the standard gear condition, in spite of the higher repetition during propulsion in low gear. Analysis of the glenohumeral joint dynamics and shoulder muscle activity during geared manual wheelchair propulsion over carpeted floor showed that the peak glenohumeral joint inferior force and flexion moment, as well as the shoulder flexors muscle activity, decreased significantly during the low gear condition. Manual wheelchair users with SCI were tested during the six-minute push tests on passive wheelchair rollers to evaluate the effects of using geared wheels on energy expenditure. The results indicated that using geared wheels in the low gear condition significantly increased the energy cost of propulsion and decreased the intensity of wheelchair propulsion. The findings of this dissertation demonstrate that using geared wheels in comparison to standard wheels decreases the demands on the upper extremity of manual wheelchair users, which may ultimately help preserve upper limb function leading to higher levels of activity, independence and quality of life

Use of stance control knee-ankle-foot orthoses : a review of the literature

The use of stance control orthotic knee joints are becoming increasingly popular as unlike locked knee-ankle-foot orthoses, these joints allow the limb to swing freely in swing phase while providing stance phase stability, thus aiming to promote a more physiological and energy efficient gait. It is of paramount importance that all aspects of this technology is monitored and evaluated as the demand for evidence based practice and cost effective rehabilitation increases. A robust and thorough literature review was conducted to retrieve all articles which evaluated the use of stance control orthotic knee joints. All relevant databases were searched, including The Knowledge Network, ProQuest, Web of Knowledge, RECAL Legacy, PubMed and Engineering Village. Papers were selected for review if they addressed the use and effectiveness of commercially available stance control orthotic knee joints and included participant(s) trialling the SCKAFO. A total of 11 publications were reviewed and the following questions were developed and answered according to the best available evidence: 1. The effect SCKAFO (stance control knee-ankle-foot orthoses) systems have on kinetic and kinematic gait parameters 2. The effect SCKAFO systems have on the temporal and spatial parameters of gait 3. The effect SCKAFO systems have on the cardiopulmonary and metabolic cost of walking. 4. The effect SCKAFO systems have on muscle power/generation 5. Patient’s perceptions/ compliance of SCKAFO systems Although current research is limited and lacks in methodological quality the evidence available does, on a whole, indicate a positive benefit in the use of SCKAFOs. This is with respect to increased knee flexion during swing phase resulting in sufficient ground clearance, decreased compensatory movements to facilitate swing phase clearance and improved temporal and spatial gait parameters. With the right methodological approach, the benefits of using a SCKAFO system can be evidenced and the research more effectively converted into clinical practice

AN EMG OPTIMIZATION MODEL OF THE KINETIC DEMANDS ON THE LOWER BACK DURING ASYMMETRICAL GAIT AND LOAD CARRIAGE

Gait asymmetries are associated with a high incidence of lower back pain (LBP). Although there are several causes of gait asymmetry (i.e. amputation, injury, or deformities), lower back kinetic demands have not been quantified and suitably compared due to experimental limitations in these clinical populations. Further, the impact of gait asymmetry on lower back demands during carrying tasks has not been established. This dissertation addressed these issues by artificially and safely inducing gait asymmetry in healthy able-bodied participants during walking and carrying tasks. LBP risk was assessed by L5/S1 vertebral joint force levels estimated with an OpenSim musculoskeletal model of the lower back adapted to incorporate participant-specific responses using an EMG optimization approach. The model was evaluated systematically for force estimate efficacy and sensitivity to input parameters prior to gait asymmetry assessments. Twelve participants performed walking and carrying tasks on a treadmill at individually scaled speeds while kinematics, external kinetics, and muscle activities (EMG) were recorded. Walking conditions consisted of unperturbed symmetrical gait, and asymmetrical gait induced by perturbing the right leg with a 2.54 cm shoe leveler, ~1 kg ankle weight, combined weight and shoe leveler, or a clinical walking boot that restricted ankle joint motion and added mass. Load carrying was performed while holding 7.5% and 15% bodyweight dumbbells in one or two hands during symmetric gait and asymmetric gait induced by the walking boot. The perturbations were successful in producing different degrees of gait asymmetry. However, L5/S1 joint forces were not significantly different between conditions despite unique spatiotemporal asymmetries. This indicates that LBP in those with gait asymmetry may not be due solely to level planar walking. During carrying tasks, gait asymmetry induced by the walking boot increased some metrics of lower back loading. Further, carrying a load in the hand contralateral to the walking boot produced larger forces than when carried on the same side. These results emphasize the importance of evaluating specific sources of gait asymmetry during daily activities other than walking when assessing LBP risk and would encourage more inclusive ergonomic carrying guidelines

The effect of prefabricated wrist-hand orthoses on performing activities of daily living

Wrist-hand orthoses (WHOs) are commonly prescribed to manage the functional deficit associated with the wrist as a result of rheumatoid changes. The common presentation of the wrist is one of flexion and radial deviation with ulnar deviation of the fingers. This wrist position Results in altered biomechanics compromising hand function during activities of daily living (ADL). A paucity of evidence exists which suggests that improvements in ADL with WHO use are very task specific. Using normal subjects, and thus in the absence of pain as a limiting factor, the impact of ten WHOs on performing five ADLs tasks was investigated. The tasks were selected to represent common grip patterns and tests were performed with and without WHOs by right-handed, females, aged 20-50 years over a ten week period. The time taken to complete each task was recorded and a wrist goniometer, elbow goniometer and a forearm torsiometer were used to measure joint motion. Results show that, although orthoses may restrict the motion required to perform a task, participants do not use the full range of motion which the orthoses permit. The altered wrist position measured may be attributable to a modified method of performing the task or to a necessary change in grip pattern, resulting in an increased time in task performance. The effect of WHO use on ADL is task specific and may initially impede function. This could have an effect on WHO compliance if there appears to be no immediate benefits. This orthotic effect may be related to restriction of wrist motion or an inability to achieve the necessary grip patterns due to the designs of the orthoses