Variability explained by strength, body composition and gait impairment in activity and participation measures for children with cerebral palsy: a multicentre study.

OBJECTIVE: To determine the amount of variability in scores on activity and participation measures used to assess ambulatory individuals with cerebral palsy explained by strength, body composition, gait impairment and participant characteristics. DESIGN: Multicentre prospective cross-sectional study. SETTING: Seven paediatric-orthopaedic specialty hospitals. PARTICIPANTS: Three hundred and seventy-seven ambulatory individuals (241 males, 136 females) with cerebral palsy, Gross Motor Function Classification System (GMFCS) levels I-III (I = 148, II = 153, III = 76), ages 8-18 years (mean 12 years 9 months, SD 2 years 8 months). METHODS: Participants completed assessments of GMFCS level, patient history, lower extremity muscle strength, Gross Motor Function Measure (GMFM-66), Pediatric Outcomes Data Collection Instrument (PODCI), instrumented gait analysis, 1 minute walk test, Timed Up-and-Go and body composition. Multiple linear regression and bootstrap analyses were performed for each outcome measure, stratified by GMFCS level. RESULTS: The amount of variability in outcome measures explained by participant characteristics, strength, and gait impairment ranged from 11% to 50%. Gait impairment was the most common predictor variable and frequently explained the greatest variance across all outcome measures and GMFCS levels. As gait impairment increased, scores on outcome measures decreased. Strength findings were inconsistent and not a primary factor. Body composition contributed minimally (<4%) in explaining variability. Participant characteristics (cerebral palsy type, gestational age and age at walking onset), were significant predictor variables in several models. CONCLUSIONS: Variability in outcome measure scores is multifaceted and only partially explained by strength and gait impairment illustrating the challenges of attempting to explain variation within this heterogeneous population. Clinicians treating individuals with cerebral palsy should consider this when developing treatment paradigms.

One-Minute Walk and modified Timed Up and Go tests in children with cerebral palsy: performance and minimum clinically important differences.

AIM This prospective multicenter study assessed performance and changes over time, with and without surgical intervention, in the modified Timed Up and Go (mTUG) and One-Minute Walk tests (1MWT) in children with bilateral cerebral palsy (CP). Minimum clinically important differences (MCIDs) were established for these tools. METHOD Two hundred and nineteen participants with bilateral spastic CP (Gross Motor Function Classification System [GMFCS] levels I­III) were evaluated at baseline and 12 months follow-up. The non-surgical group (n=168; 54 females, 114 males; mean age 12y 11mo, [SD 2y 7mo], range 8y 1mo­19y) had no surgical interventions during the study. The surgical group (n=51; 19 females, 32 males; mean age 12y 10mo [SD 2y 8mo] range 8y 2mo­17y 5mo) underwent soft-tissue and/or bony procedures within 12 months from baseline. The mTUG and 1MWT were collected and MCIDs were established from the change scores of the non-surgical group. RESULTS Dependent walkers (GMFCS level III) required more time to complete the mTUG (p≤0.01) than independent walkers (GMFCS levels I and II). For the 1MWT, distance walked decreased with increasing impairment (p≤0.01). 1MWT and mTUG change scores were not significantly different at any GMFCS level for either the surgical or non-surgical groups (p≤0.01). INTERPRETATION Children with varying levels of function (GMFCS level) perform differently on the 1MWT and mTUG. The data and MCID values can assist clinicians in interpreting changes over time and in assessing interventions.

Accuracy of skinfold and bioelectrical impedance assessments of body fat percentage in ambulatory individuals with cerebral palsy.

AIM: This study assessed the accuracy of measurements of body fat percentage in ambulatory individuals with cerebral palsy (CP) from bioelectrical impedance analysis (BIA) and skinfold equations. METHOD: One hundred and twenty-eight individuals (65 males, 63 females; mean age 12y, SD 3, range 6-18y) with CP (Gross Motor Function Classification System [GMFCS] levels I (n=6), II (n=46), and III (n=19) participated. Body fat percentage was estimated from (1) BIA using standing height and estimated heights (knee height and tibial length) and (2) triceps and subscapular skinfolds using standard and CP-specific equations. All estimates of body fat percentage were compared with body fat percentage from dual-energy X-ray absorptiometry (DXA) scans. Differences between DXA, BIA, and skinfold body fat percentage were analyzed by comparing mean differences. Agreement was assessed by Bland-Altman plots and concordance correlation coefficients (CCC). RESULTS: BMI was moderately correlated with DXA (Pearson's r=0.53). BIA body fat percentage was significantly different from DXA when using estimated heights (95% confidence intervals [CIs] do not contain 0) but not standing height (95% CI -1.9 to 0.4). CCCs for all BIA comparisons indicated good to excellent agreement (0.75-0.82) with DXA. Body fat percentage from skinfold measurements and CP-specific equations was not significantly different from DXA (mean 0.8%; SD 5.3%; 95% CI -0.2 to 1.7) and demonstrated strong agreement with DXA (CCC 0.86). INTERPRETATION: Accurate measures of body fat percentage can be obtained using BIA and two skinfold measurements (CP-specific equations) in ambulatory individuals with CP. These findings should encourage assessments of body fat in clinical and research practices.

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.

Determinants of intensity of participation in leisure and recreational activities by youth with cerebral palsy.

OBJECTIVE: To test a model of determinants of intensity of participation in leisure and recreational activities by youth with cerebral palsy (CP). DESIGN: Prospective cohort study. SETTING: Children's hospitals (N=7). PARTICIPANTS: Youth with CP (N=205; age, 13-21y) and their parents. The sample included 107 (57.2%) males and 26 (12.7%) to 57 (27.8%) youth in each of the 5 levels of the Gross Motor Function Classification System (GMFCS). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Youth completed the Children's Assessment of Participation and Enjoyment by means of an interview. Parents completed the Pediatric Outcomes Data Collection Instrument, Family Environment Scale, Coping Inventory, Measure of Processes of Care, a demographic questionnaire, and a services questionnaire. RESULTS: Structural equation modeling was used to test the model. Fit statistics indicate good model fit. The model explains 35% of the variance in intensity of participation. Path coefficients (P ≤ .05) indicate that higher physical ability, higher enjoyment, younger age, female sex, and higher family activity orientation are associated with higher intensity of participation. GMFCS level and caregiver education have indirect effects on intensity of participation. The path between services and intensity of participation was not significant. CONCLUSIONS: Participation by youth with CP is influenced by multiple factors. The influence of physical activity supports the importance of activity accommodations and assistive technology for youth who are not capable of improving physical ability. Knowledge of family activity orientation is important for identifying opportunities for participation. The unexplained variance suggests that the model should include other determinants, such as physical accessibility and availability of transportation and community leisure and recreational activities.

Self-concept of adults with cerebral palsy.

PURPOSE: To describe the self-concept of adults with cerebral palsy (CP). METHOD: Cross-sectional design included the Tennessee Self-Concept Scale, version 2 (TSCS:2), Functional Independence Measure (FIM™), Beck Depression Index II (BDI®-II), Craig Hospital Inventory of Environmental Factors (CHIEF), Diener's Satisfaction with Life Scale (SWLS), Gross Motor Functional Classification System (GMFCS) levels and demographic questions. RESULTS: One hundred and two people with CP (52 females, mean age=26) participated. Thirty-eight participants had unreliable answers as indicated by validity scales and were excluded from the analysis. Ten participants had high self-concept; 41 had average self-concept and 13 had low total self-concept. Self-concept had a fair and inverse association with the BDI-II (Pearson's r= -0.3, p<0.01) and a moderate and direct association with the SWLS (Pearson's r=0.4, p<0.001). Self-concept was not associated with GMFCS level or FIM score. Family and Personal sub-domain scores were lowest sub-domain scores for people with low self-concept (p<0.01). CONCLUSION: The majority of the participants in this sample had a healthy self-concept; and self-concept was not associated with severity of CP, but with lack of depression and life satisfaction. Results suggest the need for family centred care into adulthood.

Structural bone allograft in pediatric foot surgery.

Structural bone allografts are used in a variety of surgical procedures, but only a few investigators have examined their use and associated complications in the pediatric population specifically. In a retrospective review of pediatric foot procedures, we sought to determine types and rates of complications associated with structural bone allografts as well as time to incorporation of these allografts. Minimum follow-up was 12 months. Eighteen patients with 31 structural allografts were reviewed. The total complication rate was 7.1%, and the allograft incorporation rate was 90% (mean time after surgery, 9 months). Mean follow-up was 22 months. There were no pseudarthroses, nonunions, or fractures at the bone-graft sites. Structural bone allografts can be safely used in foot procedures in pediatric neuromuscular patients without major risk for complications, and their use can reduce autograft-harvest morbidity in pediatric patients with neuromuscular conditions.

Tibial length growth curves for ambulatory children and adolescents with cerebral palsy.

AIM: The aim of this study was to generate growth curves for ambulatory children and adolescents with cerebral palsy (CP) using tibial lengths and to determine if they differed according to sex or Gross Motor Function Classification System (GMFCS) level. METHOD: Growth data were studied from a cohort of 750 participants (442 males, 308 females [1199 visits]; mean age 10 y 9 mo, SD 3 y 4 mo, range 4-21 y) with CP (hemiplegia, n=163; diplegia, n=573; triplegia, n=11; quadriplegia n=2; GMFCS levels I-III), and 165 typically developing children (96 males, 115 females; [211 visits]) mean age 10 y 9 mo, SD 4 y 2 mo, range 4-19 y). Tibial length measurements calculated from data collected during routine gait analyses were validated using anthropometric tibial length measurements and were used to generate growth curves for males and females classified as GMFCS level I, II, or III. Growth was compared in participants of different sexes and GMFCS levels using the median curves. RESULTS: Growth curves for males and females (GMFCS levels I-III) with estimate lines for 3rd, 10th, 25th, 50th, 75th, 90th, and 97th centiles were generated. Mean tibial length was greater in males than in females in all GMFCS levels. Tibial lengths were shorter in participants classified as GMFCS level III than in those classified as GMFCS level I or II. INTERPRETATION: To our knowledge this is the first large-scale investigation of bone growth in ambulatory children and adolescents with CP. The large sample made it possible to generate growth curves and to provide insight into growth trends. The study findings serve as a basis for analysis of the relationships between growth, function, and treatment outcomes.

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.

A prospective cohort study of the effects of lower extremity orthopaedic surgery on outcome measures in ambulatory children with cerebral palsy.

BACKGROUND: Lower-extremity musculotendinous surgery is standard treatment for ambulatory children with deformities such as joint contractures and bony torsions resulting from cerebral palsy (CP). However, evidence of efficacy is limited to retrospective, uncontrolled studies with small sample sizes focusing on gait variables and clinical examination measures. The aim of this study was to prospectively examine whether lower-extremity musculotendinous surgery in ambulatory children with CP improves impairments and function measured by gait and clinical outcome tools beyond changes found in a concurrent matched control group. METHODS: Seventy-five children with spastic CP (Gross Motor Function Classification System levels I to III, age 4 to 18 y) that underwent surgery to improve gait were individually matched on the basis of sex, Gross Motor Function Classification System level, and CP subtype to a nonsurgical cohort, minimizing differences in age and Gross Motor Function Measure Dimension E. At baseline and at least 12 months after baseline or surgery, participants completed gait analysis and Gross Motor Function Measure, and parents completed outcome questionnaires. Mean changes at follow-up were compared using analysis of covariance adjusted for baseline differences. RESULTS: Surgery ranged from single-level soft tissue release to multilevel bony and/or soft tissue procedures. At follow-up, after correcting for baseline differences, Gillette Gait Index, Pediatric Outcomes Data Collection Instrument Expectations, and Pediatric Quality of Life Inventory (PedsQL) Physical Functioning improved significantly for the surgical group compared with the nonsurgical group, which showed minimal change. CONCLUSIONS: On the basis of a matched concurrent data set, there was significant improvement in function after 1 year for a surgical group compared with a nonsurgical group as measured by the Gillette Gait Index, with few significant changes noted in outcome measures. Changes over 1 year are minimal in the nonsurgical group, supporting the possibility of ethically performing a randomized controlled trial using nonsurgical controls. LEVEL OF EVIDENCE: Therapeutic level 2. Prospective comparative study.

Clinical applications of outcome tools in ambulatory children with cerebral palsy.

This article provides an overview of outcome tools commonly used to assess ambulatory children with cerebral palsy, research findings from a recent large multi-center study, and ways to integrate the research findings into clinical practice. The information presented in this article and in the referenced articles provides information on: outcome tools' discriminatory ability and responsiveness; readily available comparison data on 7 commonly used outcome tools that can be used at the point of care; prediction equations for the Parent report Pediatric Outcomes Data Collection Instrument (PODCI) by age and Gross Motor Function Classification System (GMFCS) level; and minimum clinically important difference thresholds by GMFCS level. This information can help clinicians select the best outcome tools to discriminate among severity levels and avoid ceiling effects. The scores provided allow direct comparisons between a specific patient and a matched cohort, assisting clinicians in the creation of comprehensive and individualized evaluation and management plans. Use of appropriate outcome tools to assess children with cerebral palsy can lead to best practices and reduced costs in the clinical setting.

Novel three-dimensional MRI technique for study of cartilaginous hip surfaces in Legg-Calvé-Perthes disease.

Treatment of Legg-Calvé-Perthes disease (LCPD) may improve if new knowledge can be obtained regarding how articular cartilage changes shape during the course of this disorder. A new technique is presented showing how analyses of magnetic resonance images can be used to quantify the three-dimensional changes in the femoral and acetabular articulating cartilage surfaces of children with LCPD. Ten male subjects (8 +/- 1 years) with unilateral LCPD were enrolled in this IRB approved study. Sets of magnetic resonance images of both hips were obtained at three different times. Three-dimensional virtual models of the cartilage were created from these images, and mathematical spheres were fit to the articulating surfaces. Five parameters (size, shape deformity (sphericity error), radial growth rate, joint fit, and joint incongruity) were used to quantify cartilage surface shape. Data were analyzed by using a linear mixed-model. Joint incongruity, i.e., the distance between the centers of the femoral and acetabular spheres, was slightly more than 2.5 times larger (p = 0.001) in LCPD hips than the contralateral normal hips. Cartilage shape deformity was 65% larger in hips with LCPD than in normal hips. Growth rates of the femoral head and the opposing acetabular surface showed that distortion of the femoral surface occurred first and the opposing acetabular surface followed. Mean radial difference (acetabular surface radius minus femoral surface radius) in LCPD hips was less than half (p < 0.01) the value of normal hips. Interobserver variability was approximately 10% of the value attributable to LCPD. This is the first known report presenting a technique that quantifies the three-dimensional size, deformity, growth, fit. and incongruity of the femoral and acetabular articulating cartilaginous surfaces of LCPD and contralateral normal hips. The data obtained support the use of this technique and provide pilot data for a future clinical study of LCPD. Objective assessment of cartilage shape enabled by this technique may aid future diagnoses, enable monitoring of three-dimensional femoral and acetabular remodeling, and permit quantitative assessment of treatment efficacy.

Outcomes of gastrocnemius-soleus complex lengthening for isolated equinus contracture in children with cerebral palsy.

BACKGROUND: The goal of the gastrocnemius-soleus complex (GSC) lengthenings in children with cerebral palsy (CP) is to achieve a plantigrade foot and normalize kinematics during gait. The study purpose was to evaluate the results of GSC lengthening for isolated equinus contracture in individuals with CP. It was hypothesized that GSC lengthenings would normalize passive ankle range of motion, kinematic, kinetic, and temporal spatial parameters. METHODS: Gait data from 15 able-bodied participants from the laboratory normal database and passive range of motion, kinematic, kinetic, and temporal spatial gait parameters, and oxygen cost were collected and analyzed for 27 individuals with CP (36 limbs) with isolated equinus contracture who received GSC lengthenings. Data were compared between preoperative and postoperative assessments. RESULTS: Mean age at baseline was 11.4 years (+/-3.2 y). Mean time between surgery and postoperative gait analysis was 1.3 years (+/-0.3 y). Passive range of motion measurements were obtained. Kinematic and kinetic data for the hip, knee and ankle, and temporal spatial parameters were obtained from a representative gait trial preoperatively and postoperatively. Paired t tests (P<0.05) determined whether preoperative data differed from postoperative data or from able-bodied data. The passive range of motion at the ankle was improved and normalized postoperatively. Ankle kinematics normalized without compensatory changes occurring at the knee or hip kinematics. Ankle moments and powers become more normal but did not completely normalize. Kinematics and kinetics of the hip and knee were not adversely affected. No changes in the temporal spatial data or oxygen cost occurred postoperatively. CONCLUSIONS: These data support the finding that with appropriate patient selection isolated GSC lengthening does not result in overcorrection. LEVEL OF EVIDENCE: Retrospective comparative study; level 3.

Analysis of the pediatric outcomes data collection instrument in ambulatory children with cerebral palsy using confirmatory factor analysis and item response theory methods.

BACKGROUND: Traditional use of the Pediatric Outcomes Data Collection Instrument (PODCI) assumes that all items have the same structure, are measuring the intended constructs, and assess the right levels of function to show change after orthopaedic or neurological intervention. Item response theory (IRT) methods can statistically account for inherent differences in PODCI item characteristics and thus reveal attributes of the measure important to effectiveness research. Our study uses IRT methods to determine whether PODCI items fit the projected dimensional structure of the PODCI, assess function on each dimension at the right level for a population of ambulatory children with cerebral palsy (CP), and reveal changes after intervention in this population. METHODS: Proxy-reported PODCI questionnaires for 570 ambulatory children with CP were randomly divided into 2 groups for model creation and model testing using exploratory and then confirmatory factor analysis. The resulting model was compared with the projected dimensional structure, tested for fit of individual items, and examined for gaps and ceiling effects. Response changes at 1 year were compared between those with (n = 91) and without (n = 284) surgical intervention using paired t tests. RESULTS: Factor analysis reduced the projected dimensions from 5 to 4 for this population, resulting in dimensions for mobility, upper extremity function (UEF), comfort and general health, and self-worth. All but 3 items fit their respective dimensions; ceiling effects were noted in 3 dimensions. Responses showed changes in the comfort and general health, mobility, and UEF dimensions in those who had surgery; in those children who did not have surgery, only the UEF responses changed. CONCLUSIONS: The PODCI can show change after intervention when data are analyzed using IRT methods. Ceiling effects in 3 dimensions may limit the amount of change the PODCI can show in a population of ambulatory children with CP. LEVEL OF EVIDENCE: Level II. This was a retrospective investigation of a diagnostic tool, the PODCI, using a randomized cross-sectional design for model development, and a case-control design to assess sensitivity to change.

Pediatric outcomes data collection instrument scores in ambulatory children with cerebral palsy: an analysis by age groups and severity level.

BACKGROUND: The Pediatric Outcomes Data Collection Instrument (PODCI) was developed in 1994 as a patient-based tool for use across a broad age range and wide array of musculoskeletal disorders, including children with cerebral palsy (CP). The purpose of this study was to establish means and SDs of the Parent PODCI measures by age groups and Gross Motor Function Classification System (GMFCS) levels for ambulatory children with CP. METHODS: This instrument was one of several studied in a prospective, multicenter project of ambulatory patients with CP between the aged 4 and 18 years and GMFCS levels I through III. Participants included 338 boys and 221 girls at a mean age of 11.1 years, with 370 diplegic, 162 hemiplegic, and 27 quadriplegic. Both baseline and follow-up data sets of the completed Parent PODCI responses were statistically analyzed. RESULTS: Age was identified as a significant predictor of the PODCI measures of Upper Extremity Function, Transfers and Basic Mobility, Global Function, and Happiness With Physical Condition. Gross Motor Function Classification System levels was a significant predictor of Transfers and Basic Mobility, Sports and Physical Function, and Global Function. Pattern of involvement, sex, and prior orthopaedic surgery were not statistically significant predictors for any of the Parent PODCI measures. Mean and SD scores were calculated for age groups stratified by GMFCS levels. Analysis of the follow-up data set validated the findings derived from the baseline data. Linear regression equations were derived, with age as a continuous variable and GMFCS levels as a categorical variable, to be used for Parent PODCI predicted scores. CONCLUSIONS: The results of this study provide clinicians and researchers with a set of Parent PODCI values for comparison to age- and severity-matched populations of ambulatory patients with CP.

Relationships among functional outcome measures used for assessing children with ambulatory CP.

In ambulatory children with cerebral palsy (CP), practitioners often examine outcomes using measures related to functions necessary for daily life. The Gross Motor Function Measure (GMFM) Dimensions D and E, Pediatric Outcomes Data Collection Instrument (PODCI) Parent and Child versions, Gillette Functional Assessment Questionnaire (FAQ) Walking subscale, Functional Independence Measure for Children (WeeFIM), Pediatric Quality of Life Inventory (PedsQL), temporal-spatial gait parameters, and O(2) cost during ambulation were selected for study. Cross-sectional data were collected in a prospective multicenter study of 562 participants with CP (339 males, 223 females), between 4 and 18 years of age (mean age 11y 1mo). There were 240 classified as Gross Motor Function Classification System Level I, 196 as Level II, and 126 as Level III. The tools that had the best interrelationships and underlying constructs predominately measured changes in physical function. These included portions of the FAQ, Parent PODCI, WeeFIM, and GMFM. GMFM Dimensions D and E exhibited a very strong relationship. Temporal-spatial gait parameters and O2 cost measures represented a different construct of physical function. The Child PODCI reports and both the Parent and Child PedsQL reports did not relate well to other measures, suggesting a pattern of answers not related to question content. The Parent PODCI, the FAQ Walking subscale, and GMFM Dimension E were found to be an appropriate minimum set of instruments for assessment of functional outcomes in patients with ambulatory CP.

Outcome assessments in children with cerebral palsy, part I: descriptive characteristics of GMFCS Levels I to III.

This prospective cross-sectional multicenter study assessed the relationships between Gross Motor Function Classification System (GMFCS) level and scores on outcome tools used in pediatric orthopedics. Five hundred and sixty-two participants with cerebral palsy (CP; 339 males, 223 females; age range 4-18y, mean age 11y 1mo [SD 3y 7mo]; 400 with diplegia, 162 with hemiplegia; GMFCS Levels I-III;) completed the study. The Functional Assessment Questionnaire (FAQ), Gross Motor Function Measure (GMFM) Dimensions D and E, Pediatric Quality of Life Inventory (PedsQL), the Pediatric Outcomes Data Collection Instrument (PODCI), Pediatric Functional Independence Measure (WeeFIM), temporal-spatial gait parameters, and O(2) cost were collected during one session. Descriptive characteristics are reported by GMFCS level clinicians can use for comparison with individual children. Tools with a direct relationship between outcome scores and GMFCS levels were the PODCI Parent and Child Global Function, Transfers & Basic Mobility, and Sports and Physical Function; PODCI Parent Upper Extremity Function; WeeFIM Self-care and Mobility; FAQ Question 1; GMFM Dimensions D and E; GMFM-66; O(2) cost; and temporal-spatial gait parameters. Child report scores differed significantly higher than Parent scores for six of eight PODCI subscales and three of four PedsQL dimensions. Children classified into different GMFCS levels function differently.

Outcome assessments in children with cerebral palsy, part II: discriminatory ability of outcome tools.

Discriminatory ability of several pediatric outcome tools was assessed relative to Gross Motor Function Classification System (GMFCS) level in patients with cerebral palsy. Five hundred and sixty-two patients (400 with diplegia, 162 with hemiplegia; 339 males, 223 females; age range 4-18y, mean 11y 1mo [SD 3y 7mo]), classified as GMFCS Levels I to III, participated in this prospective multicenter, cross-sectional study. All tools were completed by parents and participants when appropriate. Effect size indices (ESIs) for parametric variables and odds ratios for non-parametric data quantified the magnitude of differences across GMFCS levels. Binary logistic regression models determined discrimination, and receiver operating characteristic curves addressed sensitivity and specificity. Between Levels I and II, the most discriminatory tools were Gross Motor Function Measure (GMFM-66), velocity, and WeeFIM Mobility. Between Levels II and III, the most discriminatory tools were GMFM Dimension E, Pediatric Functional Independence Measure (WeeFIM) Self-Care and Mobility, cadence, and Gillette Functional Assessment Questionnaire Question 1. Large ESIs were noted for Parent and Child reports of Pediatric Outcomes Data Collection Instrument (PODCI) Sports & Physical Function, Parent report of PODCI Global Function, GMFM Dimension E, and GMFM-66 across all GMFCS level comparisons. The least discriminatory tools were the Quality of Life and cognition measures; however, these are important in comprehensive assessments of treatment effects.

The effects of hamstring lengthening on hip rotation.

The purpose of this study is to determine the effect on hip rotation of hamstring lengthening as measured by preoperative and postoperative motion analysis. Thirty-eight patients/76 hips in children with cerebral palsy spastic diplegia were retrospectively reviewed using presurgical and postsurgical gait analysis. Physical examination and gait analysis showed an increase in knee extension and decreased popliteal angles postoperatively. Kinematic analysis showed an increase in knee extension and decreased hip internal rotation throughout the gait cycle postoperatively as well. No difference was seen between those with internal and external rotation pattern at the hip preoperatively. As a group, the patients did not improve enough to change from internal to external rotation at the hip, suggesting that children with cerebral palsy spastic diplegia with significant internal rotation gait should have other surgical options besides hamstring lengthening when internal rotation gait of the hip is to be treated.

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.