RESUMEN
Knee osteoarthritis is thought to result, in part, from excessive and unbalanced joint loading. Toe-in and toe-out gait modifications produce alterations in external knee joint moments, and some improvements in pain over the short- and long-term. The aim of this study was to probe mechanisms of altered joint loading through the assessment of tibiofemoral contact in standing with toe-in and toe-out positions using an open magnetic resonance scanner. In this study, 15 young, healthy participants underwent standing magnetic resonance imaging of one of their knees in 3 foot positions. Images were analyzed to determine contact in the tibiofemoral joint, with primary outcomes including centroid of contact and contact area for each compartment and overall. The centroid of contact shifted laterally in the lateral compartment with both toe-in and toe-out postures, compared with the neutral position (P < .01), while contact area in the medial and lateral compartments showed no statistical differences. Findings from this study indicate that changes in the loading anatomy are present in the tibiofemoral joint with toe-in and toe-out and that a small amount of lateralization of contact, especially in the lateral compartment, does occur with these altered lower limb orientations.
Asunto(s)
Articulación de la Rodilla , Osteoartritis de la Rodilla , Fenómenos Biomecánicos , Pie , Marcha , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Postura , Dedos del Pie/diagnóstico por imagenRESUMEN
BACKGROUND: Idiopathic toe walking is a diagnosis of exclusion characterized by a persistent toe-toe gait pattern after three years of age. Treatment for toe walking includes physical therapy, orthotics, casting, Botulinum Toxin A injection into gastrocnemius/soleus muscles, and/or surgery; yet, little evidence exists regarding long-term treatment effects. RESEARCH QUESTION: The objective of this study was to explore the differences in longer-term gait outcomes and severity of idiopathic toe walking between children treated actively with casting or inactively following recommendations for stretching. METHODS: Forty-three adolescents and young adults (14.3-28.8 years; 21 females, 22 males) who had participated in an idiopathic toe walking classification study as children, returned for repeat physical examination and three-dimensional computerized gait analysis (13.4 years follow-up, range 9.4-17.8 years); 23 participants had received active treatment with casting and ankle foot orthotics⯱â¯Botulinum Toxin A injection as children and 20 participants had received inactive treatment with recommended stretching exercises. Gait analysis data were compared retrospectively from baseline to follow-up using analysis of variance; toe walking severity was compared using a Wilcoxin Signed-Rank Sums test. RESULTS: Ankle angle at initial contact, peak dorsiflexion in stance, and toe walking severity improved significantly in the active treatment group only at follow-up. Significant improvement in peak ankle power and timing of ankle kinematics and kinetics in the gait cycle were found in both groups; however, greater changes occurred in the active treatment group. Both groups showed significantly improved internal plantar flexor moments, whereas knee extension increased in stance and passive ankle dorsiflexion decreased in both groups at follow-up (pâ¯=â¯0.001). Intermittent toe walking was reported in 49% (21/43) of participants at follow-up. SIGNIFICANCE: The results of this study suggest that improvement in ankle kinematic timing and ankle kinetic gait analysis variables is sustainable, independent of conservative treatment for idiopathic toe walking in childhood.
Asunto(s)
Tratamiento Conservador/métodos , Marcha/fisiología , Ejercicios de Estiramiento Muscular , Dedos del Pie/fisiología , Adolescente , Adulto , Fenómenos Biomecánicos , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Caminata/fisiología , Adulto JovenRESUMEN
Midfoot break (MFB) is a foot deformity that can occur when ankle dorsiflexion is restricted due to muscle spasticity or contractures, causing abnormal increased motion through the midfoot. MFB has been previously described in terms of forefoot (FF) and hindfoot (HF) motion in the sagittal plane. The purpose of this study was to further classify MFB by describing FF and HF motion in the coronal and transverse planes along with plantar pressures, with the goal of optimizing treatment of this deformity. Three-dimensional foot kinematics were assessed using a multi-segment foot model in children with MFB (n=30) and children with no foot or gait abnormalities (n=30). The MFB group was subdivided into three categories: (1) Pronated MFB, (2) Supinated MFB and (3) Flat Foot MFB. Unique patterns of plantar pressures and foot kinematics were identified for each MFB group. The Pronated MFB group had increased medial midfoot pressures, increased forefoot pronation, and increased external forefoot rotation (forefoot abductus). The Supinated MFB group had increased lateral midfoot pressures, increased forefoot supination, and increased internal forefoot rotation (forefoot adductus). In the Flat Foot MFB group, midfoot pressures were increased and distributed uniformly between the medial and lateral sides, forefoot pronation was increased, and internal forefoot rotation was present. By combining this new information with previously reported methods of measuring sagittal plane kinematics of MFB, it is now possible to characterize midfoot break in terms of severity and foot-floor contact pattern.
Asunto(s)
Deformidades del Pie/clasificación , Antepié Humano/fisiopatología , Pronación/fisiología , Supinación/fisiología , Adolescente , Fenómenos Biomecánicos , Niño , Preescolar , Femenino , Deformidades del Pie/fisiopatología , Marcha/fisiología , Humanos , Masculino , PresiónRESUMEN
Midfoot break (MFB) is a foot deformity that occurs most commonly in children with cerebral palsy (CP), but may also affect children with other developmental disorders. Dynamic MFB develops because the muscles that cross the ankle joint are hypertonic, resulting in a breakdown and dysfunction of the bones within the foot. In turn, this creates excessive motion at the midfoot. With the resulting inefficient lever arm, the foot is then unable to push off the ground effectively, resulting in an inadequate and painful gait pattern. Currently, there is no standard quantitative method for detecting early stages of MFB, which would allow early intervention before further breakdown occurs. The first step in developing an objective tool for early MFB diagnosis is to examine the difference in dynamic function between a foot with MFB and a typical foot. Therefore, the main purpose of this study was to compare the differences in foot motion between children with MFB and children with typical feet (Controls) using a multi-segment kinematic foot model. We found that children with MFB had a significant decrease in peak ankle dorsiflexion compared to Controls (1.3 ± 6.4° versus 8.6 ± 3.4°) and a significant increase in peak midfoot dorsiflexion compared to Controls (15.2 ± 4.9° versus 6.4 ± 1.9°). This study may help clinicians track the progression of MFB and help standardize treatment recommendations for children with this type of foot deformity.
Asunto(s)
Parálisis Cerebral/fisiopatología , Deformidades del Pie/fisiopatología , Trastornos Neurológicos de la Marcha/fisiopatología , Adolescente , Articulación del Tobillo/fisiología , Articulación del Tobillo/fisiopatología , Fenómenos Biomecánicos , Estudios de Casos y Controles , Parálisis Cerebral/complicaciones , Niño , Preescolar , Deformidades del Pie/etiología , Marcha/fisiología , Trastornos Neurológicos de la Marcha/etiología , HumanosRESUMEN
In order to establish the clinical utility of pedobarography in the treatment of childhood foot pathology, a reliable set of pedobarograph data describing non-pathologic feet is required. The purpose of this study was to describe the pedobarographic profiles of normal children across all ages, with specific focus on young children and explore age-related differences in foot pressure patterns. The Tekscan HR Mat pressure measurement system was used in a protocol involving a dynamic test at self-selected speed and walking pattern of 146 normal children (age range 1.6-14.9 years). Relative force and timing data were obtained across five foot segments (heel, lateral midfoot, medial midfoot, lateral forefoot, and medial forefoot). Analysis of variance (ANOVA) techniques were applied to determine if there were any age-related differences in foot pressure profiles in children across four a priori pedobarograph variables: % of stance at initiation at the heel, % of stance at initiation at the medial midfoot, maximum % force at the heel, maximum % force at the medial midfoot. Differences in foot pressure profiles were distinguished across three age groups: (1) Group 1: <2 years; (2) Group 2: 2-5 years; and (3) Group 3: >5 years. Age-related differences in initiation patterns, force transmission, and the amount of time spent on each foot segment provide evidence for maturation of children's foot pressure profiles from a flatfoot pattern in the young child to a curvilinear pattern in the older child.
Asunto(s)
Pie/fisiología , Adolescente , Factores de Edad , Análisis de Varianza , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Presión , Caminata/fisiologíaRESUMEN
Idiopathic toe walking (ITW), considered abnormal after the age of 3 years, is a common complaint seen by medical professionals, especially orthopaedic surgeons and physiotherapists. A classification for idiopathic toe walking would be helpful to better understand the condition, delineate true idiopathic toe walkers from patients with other conditions, and allow for assignment of a severity gradation, thereby directing management of ITW. The purpose of this study was to describe idiopathic toe walking and develop a toe walking classification scheme in a large sample of children. Three primary criteria, presence of a first ankle rocker, presence of an early third ankle rocker, and predominant early ankle moment, were used to classify idiopathic toe walking into three severity groups: Type 1 mild; Type 2 moderate; and Type 3 severe. Supporting data, based on ankle range of motion, sagittal joint powers, knee kinematics, and EMG data were also analyzed. Prospectively collected gait analysis data of 133 children (266 feet) with idiopathic toe walking were analyzed. Subjects' age range was from 4.19 to 15.96 years with a mean age of 8.80 years. Pooling right and left foot data, 40 feet were classified as Type 1, 129 were classified as Type 2, and 90 were classified as Type 3. Seven feet were unclassifiable. Statistical analysis of continuous variables comprising the primary criteria showed that the toe walking severity classification was able to differentiate between three levels of toe walking severity. This classification allowed for the quantitative description of the idiopathic toe walking pattern as well as the delineation of three distinct types of ITW patients (mild, moderate, and severe).
Asunto(s)
Marcha/fisiología , Caminata/fisiología , Adolescente , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos , Preescolar , Femenino , Humanos , Articulación de la Rodilla/fisiología , Masculino , Estudios Prospectivos , Rango del Movimiento Articular , Dedos del Pie/fisiologíaRESUMEN
The aim of this study was to determine whether cyclists modify the pattern of force application to become more effective during a prolonged ride to exhaustion. Twelve competitive male cyclists completed a steady-rate exercise ride to exhaustion at 80% of their maximum power output at 90 rev x min(-1) on a cycle ergometer. Pedal force, pedal and crank angle data were collected from an instrumented bicycle for three pedalling cycles at the end of the first and final minutes of the exercise test with simultaneous video recording of the lower limbs. Kinematic and force data were combined to compute hip, knee and ankle joint moments. There were changes in the pattern of force application, joint kinematics and joint moments of force. Comparison of the first minute and the final minute ride revealed significantly increased peak effective force (340 +/- 65.0 and 377 +/- 74.8 N for the first and final minute, respectively; F1,11 = 7.44, P = 0.02), increased positive (28.4 +/- 4.5 and 30.5 +/- 4.8 N x s for the first and final minute, respectively; F1,11 = 7.80, P = 0.02) and negative angular impulses (-1.5 +/- 1.6 and -2.4 +/- 1.5 N x s for the first and final minute, respectively; F1,11 = 4.50, P = 0.06). Contrary to our initial assumptions, it would appear that riders became less effective during the recovery phase, which increased the demand for forces during the propulsive phase. Training the pattern of force application to improve effectiveness may be a useful strategy to prolong an endurance ride.