AFOs Improve Stride Length and Gait Velocity but Not Motor Function for Most with Mild Cerebral Palsy.

Ankle-foot orthoses (AFOs) are prescribed to children with cerebral palsy (CP) in hopes of improving their gait and gross motor activities. The purpose of this retrospective study was to examine if clinically significant changes in gross motor function occur with the use of AFOs in children and adolescents diagnosed with CP (Gross Motor Function Classification System levels I and II). Data from 124 clinical assessments were analyzed. Based on minimum clinically important difference (MCID), 77% of subjects demonstrated an increase in stride length, 45% of subjects demonstrated an increase in walking velocity, and 30% demonstrated a decrease in cadence. Additionally, 27% of the subjects demonstrated increase in gait deviation index (GDI). Deterioration in gait was evident by decreases in walking speed (5% of subjects), increases in cadence (11% of subjects), and 15% of subjects demonstrated decreases in gait deviation index. Twenty-two percent of subjects demonstrated no change in stride lengths and one participant demonstrated a decrease in stride length. However, AFOs improved Gross Motor Function Measure (GMFM) scores for a minority (10%) of children with mild CP (GMFCS level I and II), with 82-85% of subjects demonstrating no change in GMFM scores and 5-7% demonstrating decrease in GMFM scores.

What is the minimum torque required to obtain passive elbow end range of motion?

BACKGROUND: Passive range of motion is a common clinical assessment. The point at which passive end range of motion is measured is typically described by the 'end-feel'of the joint. RESEARCH QUESTION: What is the minimum amount of torque required to obtain passive elbow flexion and extension in children? METHODS: Twenty-five children (age, 7.5 ± 1.6 years-old), who had previously sustained unilateral distal humeral fractures, participated in this prospective study.Passive elbow flexion and extension was measured at least 8 weeks and up to one year out of cast. Motion capture cameras were used to track twenty-one reflective markers placed on subjects and two markers attached to the pad of a force transducer.Five trials of passive range of motion (flexion and extension) were performed on both arms. Elbow joint moments were calculated as products of the forces applied and lengths to the elbow centers. A one way ANOVA was used to determine differences in moments for flexion and extension for both involved and uninvolved limbs. Pairedsamples t-tests were used to determine differences between the involved and the uninvolved limbs for both maximum flexion and extension. RESULTS: There was no difference in the minimum mean joint moment (2.7 ± 1.1 Nm) at end range of motion. However, differences in passive range of motion was found between involved and uninvolved elbows (flexion p < .001; extension p = .001). SIGNIFICANCE: The results demonstrate therapists obtained end range of passive elbow flexion and extension applying the same amount of minimum torque. A small torque is sufficient to achieve end range of elbow motion for children. This torque can be used in guiding clinical practice for assessing passive range of elbow motion in pediatric population. Because of a paucity of data for any joint, future research developing force data for other joints should be conducted.

Development of a method to produce a valid and reliable foot mask for plantar pressure evaluation in children with clubfoot.

The purposes of this article are to describe common masking inaccuracies, provide a standard methodology for correcting inaccuracies, and report intra/interclinician reliability when novice and experts mask foot pressures for children with clubfoot. Foot pressures from 26 children (ages 2.6-12.9 years) with unilateral clubfoot were utilized. Three raters were used for intra/interclinician reliability: one expert masker with 8 years of experience and two novice maskers. For children with unilateral clubfoot, automated masking was inaccurate in 4% of trials on the unaffected side and 24% of trails on the affected side. Novice and expert maskers report good-excellent reliability (interclass correlation coefficient range 0.61-1.0) when identifying and correcting inaccurate masks. To obtain accurate and reliable foot pressure data, it is recommended to first utilize an automasking technique and apply manual editing. This is the first study to present a standard methodology for foot pressure mask editing, the first to present the incidence of mask inaccuracies and the first to present foot pressure masking reliability in children with clubfoot.

Midstance hamstring length is a better indicator for hamstring lengthening procedures than initial contact length.

BACKGROUND: Children with static encephalopathy often walk with excessive knee and hip flexion throughout the gait cycle. This crouch gait pattern can be debilitating. These children may undergo hamstring-lengthening procedures to correct this crouch gait. Some improve, while others remain in crouch gait or go into knee hyperextension postoperatively, which can ultimately be debilitating. RESEARCH QUESTION: Hamstring muscle-tendon length models are frequently used as indicators when making recommendations for or against hamstring lengthening procedures. According to the literature, most clinicians use the length of the hamstring complex at the initial contact phase of the gait cycle as the primary deciding factor. We hypothesize that the length of this muscle-tendon complex at the midstance phase of the gait cycle is a more stringent criteria for lengthening procedures. METHODS: A simplified hamstring length model was applied retrospectively to the pre and postoperative three dimensional gait analysis kinematics of 152 subjects to assess preoperative surgical indications and postoperative outcomes. RESULTS: Of the limbs with short hamstrings at initial contact preoperatively, 15% went into knee hyperextension following hamstring lengthening procedures. Cases of hyperextension were even higher (19%) if the hamstrings were also normal to long at midstance. If the hamstrings were short at midstance, only 6 % went into hyperextension. Increasing the criteria to short hamstrings at initial contact and midstance reduced the number of limbs with hyperextension to 0%. SIGNIFICANCE: It appears that the length of the hamstrings at midstance is an additional predictor of the risk of post-op knee hyperextension from hamstring lengthening procedures, than utilizing the length at initial contact alone. Even though short hamstrings at midstance may be an additional predictor of positive outcomes, it also results in a more conservative approach to surgery by excluding almost half of the patients with short hamstrings at initial contact only, but who may benefit from surgery.

Hamstring lengthening in females with cerebral palsy have greater effect than in males.

Children with spastic diplegia cerebral palsy often demonstrate crouched gait patterns, and typically undergo hamstring lengthenings. The objective of this retrospective study was to determine if the surgical response to medial and lateral hamstring lengthenings is different between males and females. Preoperative and postoperative kinematic data of 109 (71 males and 38 females) patients with cerebral palsy were evaluated. Females demonstrated larger decreases in popliteal angle, larger decreases in mid-stance knee flexion, and higher incidences of knee hyperextension postoperatively. Results indicate that females have larger responses to hamstring lengthenings than males.

Foot pressure analysis using the emed® in typically developing children and adolescents: A summary of current techniques and typically developing cohort data for comparison with pathology.

Foot pressure analysis is a valuable tool that can be used to quantify foot function in children. For researchers and clinicians who use foot pressure analysis, data from a typically developing population is used for comparison with subjects that have musculoskeletal conditions. However, differences between foot pressure data collection technology, data collection procedures and post-processing techniques make comparisons between devices, as well as direct comparisons of pediatric foot pressure data, difficult. When comparing data from multiple studies it is imperative that the studies utilize the same data collection and processing techniques, otherwise the data should not be directly compared. The purpose of this paper is to provide a summary of typically developing foot pressure data, explore factors that affect foot pressure data collection and provide suggestions for the standardization of foot pressure data collection and post processing. The results of this review demonstrate that the minimum data collection and processing recommendations for foot pressure data collection and post-processing are: using a midgait or two-step approach, allowing subjects to walk at their self-selected speed, collecting a minimum of three trials per foot, identifying at minimum medial and lateral hindfoot, forefoot, midfoot, the hallux and toes, and that parameters be reported in standard units.

A Cross-sectional Study of Chest Kinematics and VO2 in Children With Adolescent Idiopathic Scoliosis During Steady-state Walking.

STUDY DESIGN: A cross-sectional study. OBJECTIVE: The aim of this study was to identify the differences in oxygen consumption in children with adolescent idiopathic scoliosis (AIS) and age-matched control subjects using traditional methods and chest kinematics. SUMMARY OF BACKGROUND DATA: AIS is a disorder affecting 2 to 3% of children between the ages of 10 and 16 and accounts for up to 85% of all scoliosis cases. The spinal deformities and subsequent rib conformational changes associated with AIS can have a significant deleterious effect on the oxygen consumption for children with mild to severe scoliosis. Previous studies found that the oxygen consumption in children with AIS was significantly more than that of peers and during walking require more energy than typically developing children. METHODS: Thirty children (four male, 26 female), 11.7 to 18.7 years of age, were enrolled: 15 adolescent children diagnosed with mild to moderate AIS (mean cobb angle 36.2 degrees) and 15 matched adolescents. Oxygen consumption during steady-state treadmill walking was measured using a traditional methods and simultaneous kinematic analysis of the chest wall. RESULTS: There were no significant differences in the volume of oxygen consumed in any of the phases of treadmill walking (resting, exercise, and recovery) or in breath per minute ventilation and tidal volume between control subjects and children with scoliosis (P > 0.05). Significant differences were found between assessment methods, with the kinematic analysis overestimating the average tidal volume while walking (P < 0.05). CONCLUSION: Children with mild to moderate AIS and typically developing children do not demonstrate oxygen consumption differences when walking at a steady state on a treadmill. However, kinematic analysis of the chest wall tends to overestimate the tidal volume when walking. An offset equation is required for some variables when using kinematic data to assess oxygen consumption in children who would otherwise not comply with traditional oxygen consumption testing. LEVEL OF EVIDENCE: 3.

Pedobarographic changes in Ponseti-treated clubfeet with and without anterior tibialis tendon transfer: changes due to growth and surgical intervention.

The aim of this study was to identify significant changes in pedobarographic parameters attributed to growth versus growth and surgical intervention for uninvolved feet, clubfeet (CF) subjected to anterior tibialis tendon transfer surgery, and unilateral nonsurgical CF. Participants underwent foot-pressure analysis preoperatively and 3 years postoperatively. Six parameters related to the lateral midfoot showed increases for uninvolved and nonsurgical CF, whereas CF subjected to surgery decreased. Transferring the anterior tibialis tendon resulted in improvements beyond typical growth and in a more balanced foot postoperatively. These changes are not simply changes in the peak pressure, but changes in force/pressure over time in the lateral foot.

Do Three Different Passive Assessments of Quadriceps Spasticity Relate to the Functional Activity of Walking for Children Diagnosed with Cerebral Palsy?

A stiff-knee gait pattern is frequently associated with several impairments including quadriceps spasticity in children diagnosed with cerebral palsy (CP). The relationship of clinical measures of quadriceps spasticity and the stiff-knee gait pattern in children diagnosed with CP has not been well established. Therefore, the purpose of this study was to determine the ability of clinical measures of quadriceps spasticity (modified Ashworth scale [MAS], Ely tests, and pendulum test) to categorize a stiff-knee gait pattern in children with CP. Children were categorized as having a stiff-knee gait pattern based on kinematic and EMG gait data. Results of a logistic regression model revealed that the only significant measure was A1 of the pendulum test. Discriminant analysis functions were used to predict group membership (stiff-knee, not stiff-knee gait pattern) for each measure. The A1 of the pendulum test demonstrated the highest classification accuracy and the highest sensitivity compared to the other measures. Therefore, a negative pendulum test (indicated by an A1 value of 45 degrees or more) is more useful for ruling out a stiff-knee gait pattern compared to the other clinical measures.

A Prospective Comparison of Pulmonary Function Using Traditional and Kinematic Measures in Children With and Without Adolescent Idiopathic Scoliosis.

PURPOSE: Traditional pulmonary function testing can be difficult for both the subject and the test administrator and are dependent on the subject's effort and ability to follow directions. An alternative to traditional pulmonary function testing is the kinematic analysis of the chest wall. Kinematic analysis is a reliable and accurate method to evaluate pulmonary function testing that does not have the restrictions of traditional methods. It is the purpose of this study to present a new model for measuring chest motion during pulmonary function testing of children with adolescent idiopathic scoliosis (AIS) and able-bodied children. PROCEDURES: Traditional pulmonary function testing and kinematic assessment of the chest wall was measured simultaneously during a flow volume loop and maximum voluntary ventilation test. Fifteen children with AIS and 15 able-bodied children were measured. Differences between the two groups (AIS and able-bodied) and the two testing methods (traditional and kinematic testing) were analyzed. Correlations for the two testing methods and interclass coefficients for the kinematic analysis were measured. FINDINGS: There were no significant differences between the control group and the scoliosis group when comparing data from traditional and kinematic assessments. When comparing the differences between the traditional and kinematic data collection methods, there were significant differences for the flow volume loop and maximum voluntary ventilation. For all significant parameters, the kinematic analysis demonstrated higher values. Moderate to high Pearson correlations were found between collection methods, and high to moderate interclass correlation coefficient values were found for the kinematic analysis of the chest wall. PRINCIPAL CONCLUSIONS: Kinematics of the chest wall can be used as a valuable resource in the future when measuring pulmonary function when a traditional method is not a viable option.

Generation, absorption, and transfer of mechanical energy during walking in children.

The purpose of this study was to characterize the manner in which net joint moments and non-muscular forces generate, absorb, and transfer mechanical energy during walking in able-bodied children. Standard gait data from seven healthy subjects between 6 and 17 years of age were combined with a dynamic model of the whole body to perform a power analysis based on induced acceleration techniques. These data were used to determine how each moment and force generates energy to, absorbs energy from, and transfers energy among the major body segments. The joint moments were found to induce transfers of mechanical energy between body segments that generally exceeded the magnitudes of energy generation and absorption. The amount of energy transferred by gravitational and velocity-dependent forces was considerably less than for the joint moments. The hip and ankle joint moments had relatively simple power patterns that tended to oppose each other, particularly over the stance phase. The knee joint moment had a more complex power pattern that appeared distinct from the hip and ankle moments. The general patterns of mechanical energy flow were similar to previous reports in adults. The approach described in this paper should provide a useful complement to standard clinical gait analysis procedures.

A magnetic emergency release system for halo traction.

A magnetic emergency release system was developed for use in halo traction systems. Commercially available rare earth mounting magnets, with selected weight-carrying capacities, along with ferromagnetic receptacles, were used in line between halos and overhead pulleys to both carry the prescribed traction force and provide an emergency release in the event of excessive applied force due to a transportation accident and/or sudden application of full body weight when using overhead walkers equipped with traction systems. The magnet-receptacle pairs were calibrated with an in-line digital scale. Load rate dependencies were noted, indicating that prescribed magnet-receptacle pairs should be chosen to carry at least 110% body weight. This weight capacity is reduced to approximately 88% of body weight during higher loading rates, such as transportation accidents and accidental falls.

Reliability of the three-dimensional pendulum test for able-bodied children and children diagnosed with cerebral palsy.

This prospective study compared the test-retest reliability of thirteen variables calculated from the pendulum test in able-bodied children to those of children diagnosed with cerebral palsy. Ten healthy children and 10 children with a primary diagnosis of cerebral palsy (CP) (mean age 13 years) participated in the study. Data were collected using a three-dimensional motion analysis system on two separate occasions 73+/-28 days apart. The between day reliability ICC scores of all variables were moderate to very high (0.60-0.98) for children with CP and high to very high (0.71-0.98) for able-bodied children. The children with CP demonstrated slower maximum angular velocity compared to the able-bodied children (202 degrees /s versus 293 degrees /s, p<0.01). The time to maximum angular velocity occurred sooner for children with CP compared to able-bodied children (0.22s versus 0.34s, p<0.001). For some children with CP, the knee motions demonstrated were not oscillations of decreasing magnitude. Therefore the integrals of knee motion in each plane were calculated. For both groups of subjects the largest integrals of motion were in the sagittal plane (knee flexion/extension). The able-bodied subject's integrals were twice as large compared to subjects diagnosed with CP (p<0.01). High test-retest reliability of the variables suggests that the pendulum test provides an objective and reliable method to assess quadriceps spasticity in children with cerebral palsy.