Mode of Anesthesia and Bladder Management Following Orthopaedic Surgery in Children With Cerebral Palsy: A System Level Analysis.

BACKGROUND: Postoperative urinary retention (POUR) is a surgical complication more prevalent in children with neurodisability and associated with an increase length of hospitalization. Risk factors include pre-existing bladder dysfunction, type and duration of surgery, anesthesia medications, postoperative opioid pain management, and patient demographics. The purpose of this investigation was (1) to determine the frequency of POUR following hip/lower limb orthopaedic procedures in which epidural analgesia was used for pain management; (2) to explore factors influencing postoperative bladder management. METHODS: A retrospective analysis of clinical data was performed in an orthopaedic specialty care health care system. A health outcomes network was queried for patients with a diagnoses of cerebral palsy (ICD-9/10 codes) who had one of 57 unique CPT procedure codes corresponding to hip osteotomies or tenotomies from 2011 to 2019. All surgical observations included in analysis required a discrete data element and the confirmation of a secondary proxy. The database was also queried for postoperative medications received and patient demographics of interest. RESULTS: A total of 704 surgical procedures met inclusion criteria resulting in a patient population with a mean age of 11 years, 58% male, 53% Caucasian, and 55% classified as quadriplegia [51% Gross Motor Function Classification System (GMFCS) levels IV/V]. Three hundred and thirty-five procedures (48%) involved epidural anesthesia. Sixty-five patients required intermittent catheterization (9.2%) postoperatively following foley catheter removal, of which 23 (3.3%) required recatheterization. The rate of recatheterization was similar regardless of anesthesia mode; 1.8% for general and 1.4% for epidural and was associated with a greater number of pain medications. Epidural anesthesia resulted in significantly longer periods of catheterization. For the total group the time to urinary catheter removal differed significantly among cerebral palsy subtypes, GMFCS Level, race, and ethnicity. Factors identified as significant predictors of the length of catheterization were epidural analgesia, number of pain medications, and osteotomy. CONCLUSIONS: The number of postoperative pain medications utilized was more predictive of POUR than the mode of analgesia delivery; however, epidural analgesia and the type of surgical procedure did significantly impact the length of catheterization. LEVEL OF EVIDENCE: Level III.

A Longitudinal Study of Quantitative Muscle Strength and Functional Motor Ability in Ambulatory Boys with Duchenne Muscular Dystrophy.

BACKGROUND: Duchenne muscular dystrophy (DMD) is an X-linked recessive genetic disorder, that is characterized by progressive muscle degeneration and loss of ambulation between 7-13 years of age. Novel pharmacological agents targeting the genetic defects and disease mechanisms are becoming available; however, corticosteroid (CS) therapy remains the standard of care. OBJECTIVE: The purpose of this longitudinal study was to elucidate the effect of CS therapy on the rate of muscle strength and gross motor skill decline in boys with DMD and assess the sensitivity of selected outcome measures. METHODS: Eighty-four ambulatory boys with DMD (49-180 months), 70 on CS, 14 corticosteroid naïve (NCS), participated in this 8-year multi-site study. Outcomes included; isokinetic dynamometry, the Standing (STD) and Walking/Running/jumping (WRJ) dimensions of the Gross Motor Function Measure (GMFM), and Timed Function Tests (TFTs). Nonlinear mixed modeling procedures determined the rate of change with age and the influence of steroids. RESULTS: Despite CS therapy the rate of decline in strength with age was significant in all muscle groups assessed. CS therapy significantly slowed decline in knee extensor strength, as the NCS group declined at 3x the rate of the CS group. Concurrently, WRJ skills declined in the NCS group at twice the rate of the CS group. 4-stair climb and 10 meter walk/run performance was superior in the boys on CS therapy. CONCLUSION: CS therapy slowed the rate of muscle strength decline and afforded longer retention of select gross motor skills in boys on CS compared to boys who were NCS. Isokinetic dynamometry, Walk/Run/Jump skills, and select TFTs may prove informative in assessing the efficacy of new therapeutics in ambulatory boys with DMD.

Longitudinal changes in energy cost during walking in boys with Duchenne Muscular Dystrophy (DMD).

BACKGROUND: In boys with DMD, muscle weakness progresses in a proximal to distal pattern, leading to compensatory gait strategies, including hyperlordosis and equinus, that increase energy cost and accelerate the loss of walking capacity. RESEARCH QUESTION: The purpose of this study was to determine the changes in the energy cost of walking that occur with disease progression and to determine the optimal normalization scheme for the longitudinal assessment of the energy cost of walking in boys with DMD. METHODS: Energy cost was assessed with the COSMED K4b2. Three normalization schemes were examined: gross energy cost (EC), net non-dimensional oxygen cost (NNcost) and speed-matched control energy cost (SMC-EC). Nonlinear mixed modeling procedures determined the rate of change with age. Linear regression was used to asses the relationship between each normalization scheme and age and body height. RESULTS: 74 boys with DMD were assessed for the energy cost of walking. Velocity decreased at a significant rate (-.00245/month, p = .03) across time; (Fig. 2), while gross EC (.003248/month, p = 0.0026), NNcost (.006155/month, p < 0.0001) and SMC-EC (.001690/month, p = 0.03) all increased significantly. Age and height were significantly associated with NNcost and SMC-EC. The sensitivity of NNcost and SMC-EC to age over time were similar, while SMC-EC was less sensitive to changes in height over time than NNcost. SIGNIFICANCE: In contrast to able-bodied peers, boys with DMD decrease their velocity while all walking energy cost measures increased over time. Both SMC-EC and NNcost proved appropriate normalization schemes for boys with DMD. Compared to gross EC, both NNcost and SMC-EC were less sensitive to changes in age over time, while SMC-EC was less sensitive to changes in height than NNcost. Therefore, both NNCost and SMC-EC are suggested normalization schemes for the longitudinal assessment of energy cost in boys with DMD.

Efficacy of corticosteroid in decreasing scoliosis and extending time to loss of ambulation in a single clinic: an effectiveness trial.

PURPOSE: Pharmacologic doses of corticosteroid (CS) have been shown to ameliorate the progression of Duchenne muscular dystrophy (DMD) preserving strength, pulmonary function and ambulation as well as reducing the incidence of scoliosis. However, there are serious side effects of CS, which may impact dose tolerance. The purpose of this study was to compare the magnitude of positive CS effects on patients in our clinic to those reported in the literature. METHODS: We retrospectively reviewed medical records and radiographs of 142 DMD patients who were seen between 1st January 1991 and 31st December 2017. RESULTS: In total, 101 boys met study inclusion criteria. Of these 32 were steroid naïve, 37 took the recommended dose (standard of care, SOC) of Prednisone or Deflazacort, and 32 took a lower dose (LD). Following initiation of CS, both treatment groups showed an increase in weight velocity and decrease in linear growth velocity. Although there was a trend to later loss of ambulation (LOA) in the SOC group relative to the naïve group by one year, this was not significant, however, a small subgroup of boys on Deflazacort showed a 3.4 year later LOA than the naïve group. The incidence of scoliosis was reduced from 69% in the naïve, to 41% in the LD and 47% in the SOC group. CONCLUSIONS: Although there was a reduction in the incidence of scoliosis, it was not as robust as seen elsewhere. Many published studies have inadequate data on scoliosis probably due to the lack of inclusion of orthopaedists in the study group. LEVEL OF EVIDENCE: IV.

Longitudinal community walking activity in Duchenne muscular dystrophy.

INTRODUCTION: Natural history studies for Duchenne muscular dystrophy (DMD) have not included measures of community ambulation. METHODS: Step activity (SA) monitors quantified community ambulation in 42 boys (ages 4-16 years) with DMD with serial enrollment up to 5 years by using a repeated-measures mixed model. Additionally, data were compared with 10-meter walk/run (10mWR) speed to determine validity and sensitivity. RESULTS: There were significant declines in average strides/day and percent strides at moderate, high and pediatric high rates as a function of age (P < 0.05). Significant correlations for 10mWR versus high and low stride rates were found at baseline (P < 0.05). SA outcomes were sensitive to change over 1 year, but the direction and parameter differed by age group (younger vs. older). Changes in strides/day and percentages of high frequency and low frequency strides correlated significantly with changes in 10mWR speed (P < 0.05). DISCUSSION: Community ambulation data provide valid and sensitive real-world measures that may inform clinical trials. Muscle Nerve 57: 401-406, 2018.

Hip kinetics during gait are clinically meaningful outcomes in young boys with Duchenne muscular dystrophy.

Duchenne muscular dystrophy (DMD) is an X-linked genetic neuromuscular disorder characterized by progressive proximal to distal muscle weakness. The success of randomized clinical trials for novel therapeutics depends on outcome measurements that are sensitive to change. As the development of motor skills may lead to functional improvements in young boys with DMD, their inclusion may potentially confound clinical trials. Three-dimensional gait analysis is an under-utilized approach that can quantify joint moments and powers, which reflect functional muscle strength. In this study, gait kinetics, kinematics, spatial-temporal parameters, and timed functional tests were quantified over a one-year period for 21 boys between 4 and 8 years old who were enrolled in a multisite natural history study. At baseline, hip moments and powers were inadequate. Between the two visits, 12 boys began a corticosteroid regimen (mean duration 10.8±2.4 months) while 9 boys remained steroid-naïve. Significant between-group differences favoring steroid use were found for primary kinetic outcomes (peak hip extensor moments (p=.007), duration of hip extensor moments (p=.007), peak hip power generation (p=.028)), and spatial-temporal parameters (walking speed (p=.016) and cadence (p=.021)). Significant between-group differences were not found for kinematics or timed functional tests with the exception of the 10m walk test (p=.03), which improves in typically developing children within this age range. These results indicate that hip joint kinetics can be used to identify weakness in young boys with DMD and are sensitive to corticosteroid intervention. Inclusion of gait analysis may enhance detection of a treatment effect in clinical trials particularly for young boys with more preserved muscle function.

A comparison of the changes in the energy cost of walking between children with cerebral palsy and able-bodied peers over one year.

For ambulatory children with cerebral palsy, the assessment of walking energy efficiency is utilized to determine functional changes following surgical, pharmacologic, or orthotic interventions. While the assessment of energy efficiency is considered a useful outcome tool, minimal information exists about the changes in energy efficiency over one year in children with cerebral palsy at different gross motor function classification system (GMFCS) levels and whether the patterns of change are similar to their able-bodied peers. The purpose of this study was to determine whether energy efficiency variables change similarly over one year in children with cerebral palsy by GMFCS level and whether they differ from their age-matched peers. Forty-five able-bodied children and 34 children with cerebral palsy, GMFCS levels I-III participated in the study. Energy efficiency variables were measured at baseline and at 12 months using a Cosmed K4b2. All subjects walked at their self-selected velocity for testing around a 33 m track. Baseline velocity and net non-dimensional cost (NNcost) differed by GMFCS level and between the able-bodied peers and all GMFCS levels. Children in GMFCS level III had the highest cost and the slowest velocity. When controlling for age and baseline values, significant differences in the magnitude of change were seen in velocity between children in GMFCS level III and children in GMFCS level I and II and their able-bodied peers. In comparison to their able-bodied peers, all GMFCS levels had an increase in NNcost over one year when controlling for age and baseline NNcost, with the difference in magnitude increasing by GMFCS level. Consistent with the literature, children with cerebral palsy had an increase in NNcost over one year in comparison to their able-bodied peers, which increased with GMFCS level. This finding demonstrates that when evaluating the change in walking energy efficiency with maturation and therapeutic intervention, comparisons should be made by GMFCS level.

Classification of the gait patterns of boys with Duchenne muscular dystrophy and their relationship to function.

Corticosteroids have recently been shown to reduce expected loss of muscle strength in patients with Duchenne muscular dystrophy and extend the time they can walk. We evaluated 43 boys with the condition to determine whether taking corticosteroids is associated with differences in gait pattern, gross motor skills, energy efficiency, and timed motor performance. We used the gait deviation index to quantify the degree of gait pathology and a single measure of gait quality. There were minimal differences in gait pattern, gross motor skills, energy efficiency, or timed motor performance in boys who took corticosteroids compared with those who did not. Clustering by gait deviation index, however, revealed subtle differences between groups in gait patterns, gross motor skills, and energy efficiency. We conclude that, in boys with Duchenne muscular dystrophy, gait pattern deviations are related to function, which can provide further insight into the understanding of disease progression and treatment options to enhance function and maintain ambulation.

Relationship between clinical outcome measures and parent proxy reports of health-related quality of life in ambulatory children with Duchenne muscular dystrophy.

In Duchenne muscular dystrophy, data directly linking changes in clinical outcome measures to patient-perceived well-being are lacking. This study evaluated the relationship between clinical outcome measures used in clinical trials of ambulatory Duchenne muscular dystrophy (Vignos functional grade, quantitative knee extension strength, timed functional performance measures, and gait velocity) and 2 health-related quality of life measures--the Pediatric Outcomes Data Collection Instrument and Pediatric Quality of Life Inventory-in 52 ambulatory Duchenne muscular dystrophy subjects and 36 controls. Those with the disease showed significant decrements in parent proxy-reported health-related quality of life measures versus controls across all domains. The Pediatric Outcomes Data Collection Instrument transfers/basic mobility and sports/ physical function and the Pediatric Quality of Life Inventory physical functioning domains had significant associations with age (and hence disease progression) and traditional clinical outcome measures employed in clinical trials of ambulatory boys with Duchenne muscular dystrophy. Selected domains of the Pediatric Outcomes Data Collection Instrument and generic Pediatric Quality of Life Inventory are potential patient-reported outcome measures for clinical trials in ambulatory individuals with the disease.

Variability and minimum detectable change for walking energy efficiency variables in children with cerebral palsy.

For individuals with neuromuscular disorders, the assessment of walking energy efficiency is useful as a clinical outcome measure. Issues surrounding data collection methodology, normalization of the data, and variability and clinical utility of energy efficiency data preclude universal application. This study examined the variability and the clinical utility of velocity, energy efficiency index (EEI), gross cost, and net nondimensional cost (NNcost) in children and adolescents with spastic diplegic cerebral palsy (CP) in Gross Motor Function Classification System (GMFCS) levels I to III. The energy efficiency of walking was evaluated in 23 children and adolescents (12 males, 11 females, mean age 11y 3mo [SD 3y 5mo]; range 7-17y). Day-to-day variability was similar for all energy efficiency variables, with no significant differences in magnitude of variability between GMFCS levels. Correlations between EEI and gross cost and EEI and NNcost were fairly good (r=0.65, p<0.001, and r=0.74, p<0.001 respectively). However, only gross cost and NNcost discriminated between GMFCS levels in children with CP. Gross cost required the greatest amount of change to be considered clinically significant, whereas NNcost and EEI required a similar amount of change. For cohorts of children with CP who are evaluated over time, NNcost is the best normalization method as it reduces the variability between participants of different ages, height, and weight while evaluating only the amount of energy used to ambulate.

Walking energy expenditure in able-bodied individuals: a comparison of common measures of energy efficiency.

Assessment of walking energy efficiency is potentially useful for objectively quantifying gait efficiency; however, issues regarding methodology, day-to-day variability, inter subject variability (age and size differences) and clinical relevance prevents the assessment of walking energy efficiency from being used as a standard assessment tool. Volume of oxygen (VO(2)) and heart rate were assessed to determine the intra-subject (day-to-day) variability, the impact of age and body parameters and the clinical relevance of gross cost, Net non-dimensional Cost (NNcost) and Energy Efficiency Index (EEI) in able-bodied individuals. Gross cost demonstrated the least amount of day-to-day variability, in comparison to NNcost and EEI. Age and body parameters contributed more to the variability in gross cost than NNcost and EEI. Only net non-dimensional oxygen consumption was related to the velocity of walking. EEI did not correlate with direct measures of oxygen cost. The results from this study demonstrate that utilization of NNcost, a measure that subtracts resting oxygen consumption from walking oxygen consumption and scales for body parameters, is preferable to the traditional measures for comparing individuals of different ages and sizes and is related to the speed that the individual walks.

Comparing botulinum toxin A with casting for treatment of dynamic equinus in children with cerebral palsy.

The purpose of this study was to compare the cumulative efficacy (three treatment sessions) of botulinum toxin A (BTX-A) alone, casting alone, and the combination of BTX-A and casting in the management of dynamic equinus in ambulatory children with spastic cerebral palsy (CP). Thirty-nine children with spastic CP (mean age 5y 10mo, range 3 to 9y) were enrolled in the study. A multicenter, randomized, double blind, placebo-controlled prospective study was used. Children were randomly assigned to one of three treatment groups: BTX-A only (B), placebo injection plus casting (C), or BTX-A plus casting (B+C). The dosage for the BTX-A injections was 4U/kg per extremity. Assessments were performed at baseline, 3, 6, 7.5, and 12 months with a total of three treatments administered after the evaluations at baseline, 3, and 6 months. Primary outcome measures were ankle kinematics, velocity, and stride length. Secondary outcome measures were ankle spasticity, strength, range of motion, and ankle kinetics. Group B made no significant change in any variable at any time. Groups C and B+C demonstrated significant improvements in ankle kinematics, spasticity, passive range of motion, and dorsiflexor strength. Results of this 1-year study indicate that BTX-A alone provided no improvement in the parameters measured in this study, while casting and BTX-A/casting were effective in the short- and long-term management of dynamic equinus in children with spastic CP.

A 2-year follow-up of outcomes following orthopedic surgery or selective dorsal rhizotomy in children with spastic diplegia.

The purpose of this study was to prospectively compare the effect of orthopedic surgery (OS) and selective dorsal rhizotomy (SDR) on muscle tone, range of motion, gait and energy efficiency in ambulatory children with spastic diplegia. Twenty-five children with a diagnosis of spastic diplegia, with a mean age of 73 months, were evaluated prior to surgery and 1 and 2 years postoperatively; however, only the preoperative and 2-year postoperative data are reported here. Eighteen children received SDR and seven received OS. Children were evaluated with the Ashworth scale for muscle tone, passive range of motion (PROM), gait analysis and oxygen consumption for energy cost. Significant improvements were seen in PROM, muscle tone, gait kinematics and oxygen cost regardless of surgical intervention. Although OS and SDR interventions influence motor function through different mechanisms, the gait and energy outcomes 2 years following OS or SDR are similar.

Comparison of three ankle-foot orthosis configurations for children with spastic diplegia.

This study compared the functional efficacy of three commonly prescribed ankle-foot orthosis (AFO) configurations (solid [SAFO], hinged [HAFO], and posterior leaf spring [PLS]). Sixteen independently ambulatory children (10 males, six females; mean age 8 years 4 months, SD 2 years 4 months; range 4 years 4 months to 11 years 6 months) with spastic diplegia participated in this study. Four children were classified at level I of the Gross Motor Function Classification System (GMFCS; Palisano et al. 1997); the remaining 12 were at level II. Children were assessed barefoot (BF) at baseline (baseline assessment of energy consumption was performed with shoes on, no AFO) and in each orthotic configuration after three months of use, using gait analysis, oxygen consumption, and functional outcome measures. AFO use did not markedly alter joint kinematics or kinetics at the pelvis, hip, or knee. All AFO configurations normalized ankle kinematics in stance, increased step/stride length, decreased cadence, and decreased energy cost of walking. Functionally, all AFO configurations improved the execution of walking/running/jumping skills, upper extremity coordination, and fine motor speed/dexterity. However, the quality of gross motor skill performance and independence in mobility were unchanged. These results suggest that most children with spastic diplegia benefit functionally from AFO use. However, some children at GMFCS level II demonstrated a subtle but detrimental effect on function with HAFO use, shown by an increase in peak knee extensor moment in early stance, excessive ankle dorsiflexion, decreased walking velocity, and greater energy cost. Therefore, constraining ankle motion by using a PLS or SAFO should be considered for most, but not all, children with spastic diplegia.

Selective dorsal rhizotomy versus orthopedic surgery: a multidimensional assessment of outcome efficacy.

OBJECTIVE: To compare the efficacy of selective dorsal rhizotomy (SDR) and orthopedic surgery using multidimensional (National Center for Medical Rehabilitation Research disablement framework) outcome measures. DESIGN: Prospective outcome study. SETTING: Pediatric orthopedic hospital. PARTICIPANTS: Twenty-five children with spastic diplegia. Eighteen participants (mean age, 71.3 mo) chose SDR. Seven participants (mean age, 78.6 mo) chose orthopedic surgery. INTERVENTIONS: Children were evaluated 2 days before surgical intervention and at 6 months, 1 year, and 2 years postsurgically. MAIN OUTCOME MEASURES: The Gross Motor Performance Measure, the Gross Motor Function Measure, and the Pediatric Evaluation of Disability Inventory. RESULTS: The SDR group improved significantly in quality of movement attributes 6 months postsurgically; however, gross motor skills (standing; walking, running, and jumping) gains were seen 2 years postsurgically. The orthopedic group improved significantly in select quality of movement attributes 6 months postsurgically and in standing skills within the first postsurgical year. Self-care skills, mobility, and social function gains were seen earlier and with greater frequency in the SDR group. CONCLUSIONS: Both surgical interventions demonstrated multidimensional benefits for ambulatory children with spastic diplegia. The results suggest that qualitative changes in movement, achieved by spasticity reduction, have a greater effect on the enhancement of functional skill proficiency, thus independence, than recognized.

Stair locomotion in children with spastic hemiplegia: the impact of three different ankle foot orthosis (AFOs) configurations.

The purpose of this study was to investigate the impact of three different ankle foot orthoses (AFO) configurations on the function and kinematics of stair locomotion in children with spastic hemiplegia. Nineteen children were evaluated barefoot and with a hinged, posterior leaf spring (PLS) and solid AFO during stair ascent and descent. Stair specific items from the Pediatric Evaluation of Disability Inventory (PEDI) were used to evaluate function, while a motion measurement system was used to evaluate kinematics. The PEDI revealed no significant differences between AFOs and barefoot, although a greater percentage of children were able to keep up with their peers while wearing a hinged AFO. At the ankle, the hinged AFO provided the greatest amount of dorsiflexion during stance. All AFOs reduced plantarflexion in comparison to barefoot. The results of this study indicate that for children with spastic hemiplegia the use of an AFO did not impair stair ambulation.

Objective measurement of muscle strength in children with spastic diplegia after selective dorsal rhizotomy.

OBJECTIVES: To examine changes in isometric muscle strength at the elbow, knee, and ankle at 6 months and 1 year after selective dorsal rhizotomy (SDR) and to determine if SDR altered the frequency of muscle cocontraction. DESIGN: Prospective outcome study of a consecutive sample. SETTING: Children's hospital. PATIENTS: Ten children with spastic diplegia (7 independent and 3 dependent ambulators who used assistive devices) and 8 age-matched controls. INTERVENTIONS: SDR; physical and occupational therapy; elbow, knee, and ankle measured for flexion and extension strength during three 10-second isometric contractions for each muscle group; and monitored cocontraction measured via muscle electrodes. MAIN OUTCOME MEASURES: Absolute and normalized values of isometric strength; and alterations in the frequency of cocontraction at 6 months and 1 year postoperatively. RESULTS: Children with spastic diplegia showed significantly weaker knee extensors, ankle dorsiflexors, and ankle plantarflexors than age-matched controls. There were no significant differences in strength between the 2 groups in the elbow flexors, elbow extensors, and knee flexors. Isometric strength did not increase or decrease significantly after SDR. Cocontraction during knee extension was normalized after SDR, whereas cocontraction during ankle plantarflexion was unchanged by SDR in the majority of children. CONCLUSION: SDR did not result in a significant decrease in muscle strength in ambulatory children with spastic diplegia. The normalization of the electromyographic patterns at the knee and not the ankle after SDR lends support to the premise that in children with cerebral palsy cocontraction is multifaceted, representing a volitional strategy to enhance control, as well as a disorder of the mechanisms that govern patterns of muscle activity.