Douglas Barnes

Outcome tools used for ambulatory children with cerebral palsy: responsiveness and minimum clinically important differences

This prospective longitudinal multicenter study of ambulatory children with cerebral palsy (CP) examined changes in outcome tool score over time, tool responsiveness, and used a systematic method for defining minimum clinically important differences (MCIDs). Three hundred and eighty‐one participants with CP (Gross Motor Function Classification System [GMFCS] Levels I–III; age range 4–18y, mean age 11y [SD 4y 4mo]; 265 diplegia, 116 hemiplegia; 230 males, 151 females). At baseline and follow‐up at least 1 year later, Functional Assessment Questionnaire, Gross Motor Function Measure, Pediatric Quality of Life Inventory, Pediatric Outcomes Data Collection Instrument, Pediatric Functional Independence Measure, temporal–spatial gait parameters, and oxygen cost were collected. Adjusted standardized response means determined tool responsiveness for nonsurgical (n=292) and surgical (n=87) groups at GMFCS Levels I to III. Most scores reaching medium or large effect sizes were for GMFCS Level III. Nonsurgical group change scores were used to calculate MCID thresholds for ambulatory children with CP. These values were verified by examining participants who changed GMFCS levels. Tools measuring function were responsive when a change large enough to cause a change in GMFCS level occurred. MCID thresholds assess change in study populations over time, and serve as the basis for designing prospective intervention studies.

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 O2 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; O2 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.

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 O2 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.

Comparing functional profiles of children with hemiplegic and diplegic cerebral palsy in GMFCS Levels I and II: are separate classifications needed?

The goal was to compare children with hemiplegia with those with diplegia within Gross Motor Functional Classification System (GMFCS) levels using multiple validated outcome tools. Specifically, we proposed that children with hemiplegia would have better gait and gross motor function within levels while upper extremity function would be poorer. Data were collected on 422 ambulatory children with cerebral palsy: 261 with diplegia and 161 with hemiplegia, across seven centers. Those with hemiplegia in each level performed significantly and consistently better on gait or lower extremity function and poorer on upper extremity and school function than those with diplegia. In GMFCS Level II, the group with hemiplegia walked faster (p = 0.017), scored 6.6 points higher on Dimension E of the Gross Motor Function Measure (p = 0.017), 6.7 points lower on Upper Extremity subscale of the Pediatric Outcomes Data Collection Instrument, and 9.1 points lower on WeeFIM self-care (p = 0.002). Basing motor prognosis on GMFCS level alone may underestimate lower extremity skills of children with hemiplegia, and overestimate those of children with diplegia.

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 Pediatric Outcomes Data Collection Instrument (PODCI) and functional assessment of patients with unilateral upper extremity deficiencies.

The Pediatric Outcomes Data Collection Instrument (PODCI) questionnaire was used to quantify functional abilities of a group of unilateral upper extremity deficiency (U-UED) patients and compare them with “normal” control children. Sixty-four consecutive patients with U-UED were assessed. Parents and adolescent (ages 11-21) patients responded. Underlying diagnosis, amputation level, and type of prosthesis were recorded. Scores were compared for congenital versus traumatic etiologies for patients with various amputation levels, and for patients using prostheses versus those not using prostheses. In both parent and patient responses, PODCI scores were significantly lower than “normal” for upper extremity function and sports. Scores were similar for congenital and acquired amputees. Responses from adolescent patients showed progressively decreasing scores for upper extremity, transfers, sports, and global function with progressively proximal amputation levels. Patients using prostheses with different terminal devices did not significantly differ. Parent responses for prosthesis wearers showed lower comfort/pain scores (ie, increased pain) than non-prosthesis wearers, but no significant differences in function, including upper extremity function.

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.

The spectrum of preaxial polydactyly of the foot.

Background Polydactyly is a common congenital anomaly of the foot classified as preaxial, central, or postaxial depending on the location of the duplication. Approximately 15% of all duplications of the toes are preaxial. The purpose of this study is to report our experience in the management of preaxial polydactyly of the foot over a period of 30 years at a single institution. Patients and Methods This is a retrospective institutional review board-approved descriptive case series of 21 children representing 28 feet with preaxial foot polydactyly seen at our institution from 1977 to 2009. All subjects were analyzed in terms of sex, laterality, anatomic patterns of polydactyly, associated anomalies, family history, clinical features, surgical indications, details of surgical procedures, and outcomes after surgical interventions, using data collected from medical records, radiographs, and clinical photographs. Clinical outcomes were evaluated at the most recent examination, according to the format published by Phelps and Grogan. Results There were 21 patients (28 feet) including 11 male and 10 female subjects. Duplications were bilateral in 7 patients and unilateral in 14. The average age at surgery was 1.8 years (range: 0.8 to 4.6 y). The average follow-up was 81.7 months (range: 5 to 180 mo). According to the Watanabey classification, the distal phalangeal type occurred in 4 feet, the proximal phalangeal type in 10 feet, the metatarsal type in 10 feet, the tarsal type in 2 feet, a combined tarsal and metatarsal type in 1 foot, and a mirror type in 1 foot. All patients had associated anomalies in the affected feet. Congenital hallux varus was the most common associated anomaly (20 feet). A longitudinal epiphyseal bracket was observed in 4 feet. Clinical outcomes after the initial surgery were excellent in 8 feet, good in 15 feet, and poor in 5 feet. The 5 feet rated as poor were because of residual deformities and required additional surgery. Good results were subsequently obtained at final follow-up in all 5 feet. Conclusions In our opinion, the Watanabe classification is more useful than the Venn-Watson for surgical planning. However, we have added an additional type, representing a mirror foot which we feel is within the overall spectrum of preaxial polydactyly. Good or better results were obtained in all feet at final follow-up. Early detection and adequate excision of the longitudinal bracket affecting the phalanges or metatarsal can reduce residual deformity and the need for revision surgery. Level of Evidence Level IV (Therapeutic – Retrospective case series).

Smoking, the xenobiotic pathway, and clubfoot.

BACKGROUND Isolated clubfoot is a common orthopedic birth defect that affects approximately 135,000 newborns worldwide. It is characterized by ankle equinus, hindfoot varus, and forefoot adductus. Although numerous studies suggest a multifactorial etiology, the specific genetic and environmental components have yet to be delineated. Maternal smoking during pregnancy is the only common environmental factor consistently shown to increase the risk for clubfoot. Moreover, a positive family history of clubfoot, in conjunction with maternal smoking, increases the risk 20-fold. These findings suggest that genetic variation in smoking metabolism (xenobiotic) genes may increase susceptibility to clubfoot. Based on this reasoning, we interrogated eight candidate genes from the xenobiotic metabolism. METHODS Twenty-two single-nucleotide polymorphisms and two null alleles in these genes (CYP1A1, CYP1A2, CYP1B1, CYP2A6, EPHX1, NAT2, GSTM1, and GSTT1) were genotyped in a dataset composed of non-Hispanic white and Hispanic multiplex and simplex families. RESULTS Only rs1048943/CYP1A1 had significantly altered transmission in the aggregate and multiplex non-Hispanic white datasets (p = 0.003 and p = 0.009, respectively). Perturbation of CYP1A1 can cause an increase in harmful, adduct-forming metabolic intermediates. A significant interaction between EPHX1 and NAT2 was also found (p = 0.007). Importantly, for CYP1A2, significant maternal (p = 0.03; relative risk [RR] = 1.24; 95% confidence interval [CI], 1.04-1.44) and fetal (p = 0.01; RR = 1.33; 95% CI, 1.13-1.54) genotypic effects were identified, suggesting that both maternal and fetal genotypes can negatively impact limb development. No association was found between maternal smoking status and variation in xenobiotic metabolism genes. CONCLUSION Together, these results suggest that xenobiotic metabolism genes are unlikely to play a major role in clubfoot; however, perturbation of this pathway may still play a contributory role.

Comparison of simultaneous static standing balance data on a pressure mat and force plate in typical children and in children with cerebral palsy

BACKGROUND Balance testing is an important component in treatment planning and outcome assessment for children with Cerebral Palsy (CP). Objective measurement for static standing balance is typically conducted in motion labs utilizing force plates; however, a plantar pressure mat may prove to be a viable alternative for this type of balance assessment. METHODS This study examined static standing balance simultaneously on a force plate and a plantar pressure mat in 30 typically developing (TD) and 30 children with CP to determine if valid measures of static standing balance could be obtained in children with CP using a pressure mat. RESULTS Examination of the data provided evidence that reliable and valid measures of static standing balance can be produced with a plantar pressure mat for both groups. Five variables out of the 21 variables examined were found to be reliable and valid on both devices (pressure mat and force plate) for both subgroups (TD and CP). The variables medial/lateral (ML) average radial displacement, range moved-ML, anterior/posterior average velocity, ellipse area, and area per second were found to have high test-retest reliability (ICC > .6) and possess discriminant validity between the subgroups (TD vs. CP). Additionally, the ellipse area and area per second variables also had the ability to discriminate between GMFCS levels. A normative center of pressure (CoP) balance data set using all 21 variables was also established for typically developing children for both devices (pressure mat and force plate) within this study. SIGNIFICANCE The ability to utilize a portable plantar pressure mat for quick and reliable standing balance measurement allows for expanded ability to capture objective data in a variety of settings thereby increasing opportunity for outcomes analysis.