Chantel C. Barney

Motor function predicts parent-reported musculoskeletal pain in children with cerebral palsy.

BACKGROUND The relationship between pain and motor function is not well understood, especially for children and adolescents with communication and motor impairments associated with cerebral palsy (CP). OBJECTIVES To determine whether a predictive relationship between motor function and musculoskeletal pain exists in children with CP. METHODS Following informed consent, caregivers of 34 pediatric patients with CP (mean [± SD] age 9.37±4.49 years; 80.0% male) completed pain- and function-related measures. Parents completed the Dalhousie Pain Interview and the Brief Pain Inventory based on a one-week recall to determine whether pain had been experienced in the past week, its general description, possible cause, duration, frequency, intensity and interference with daily function. The Gross Motor Function Classification System (GMFCS) was used to classify the motor involvement of the child based on their functional ability and their need for assistive devices for mobility. RESULTS GMFCS level significantly predicted parent-reported musculoskeletal pain frequency (P<0.02), duration (P=0.05) and intensity (P<0.01). Duration of pain was significantly related to interference with activities of daily living (P<0.05). CONCLUSIONS Children with CP with greater motor involvement, as indexed by GMFCS level, may be at risk for increased pain (intensity, frequency and duration) that interfers with activities of daily living. The clinical index of suspicion should be raised accordingly when evaluating children with developmental disability who cannot self-report reliably.

Can biomarkers differentiate pain and no pain subgroups of nonverbal children with cerebral palsy? A preliminary investigation based on noninvasive saliva sampling.

OBJECTIVE Assessing and treating pain in nonverbal children with developmental disabilities are a clinical challenge. Current assessment approaches rely on clinical impression and behavioral rating scales completed by proxy report. Given the growing health relevance of the salivary metabolome, we undertook a translational-oriented feasibility study using proton nuclear magnetic resonance (NMR) spectroscopy and neuropeptide/cytokine/hormone detection to compare a set of salivary biomarkers relevant to nociception. DESIGN Within-group observational design. SETTING Tertiary pediatric rehabilitation hospital. SUBJECTS Ten nonverbal pediatric patients with cerebral palsy with and without pain. METHODS Unstimulated (passively collected) saliva was collected using oral swabs followed by perchloric acid extraction and analyzed on a Bruker Avance 700 MHz NMR spectrometer. We also measured salivary levels of several cytokines, chemokines, hormones, and neuropeptides. RESULTS Partial least squares discriminant analysis showed separation of those children with/without pain for a number of different biomarkers. The majority of the salivary metabolite, neuropeptide, cytokine, and hormone levels were higher in children with pain vs no pain. CONCLUSIONS The ease of collection and noninvasive manner in which the samples were collected and analyzed support the possibility of the regular predictive use of this novel biomarker-monitoring method in clinical practice.

Peripheral Innervation in Children With Global Developmental Delay Biomarker for Risk for Self-Injurious Behavior?

The relation between somatosensory mechanisms and self-injury among children with neurologic impairments associated with developmental delay is not well understood. We evaluated the feasibility of procuring skin biopsies to examine epidermal nerve fiber density and reported self-injury. Following informed parental consent, epidermal skin biopsies were obtained from a distal leg site with no pre-existing skin damage from 11 children with global developmental delay (55% male; mean age = 36.8 months, 17-63 months). Visual microscopic examination and quantitative analyses showed extremely high epidermal nerve fiber density values for some children. Children with reported self-injury (5/11) had significantly (P < .02) greater density values (138.8, standard deviation = 45.5) than children without self-injury (80.5, standard deviation = 17.5). Results from this novel immunohistologic analysis of skin in very young children with neurodevelopmental delays suggest it may be a useful tool to study peripheral innervation as a possible sensory risk factor for self-injury.

Infrared Thermal Analysis and Individual Differences in Skin Temperature Asymmetry in Rett Syndrome

PURPOSE We evaluated the feasibility of using a portable infrared thermal camera to quantify the degree of thermal dysregulation (cold hands/feet) and test for naturally occurring within-patient skin temperature asymmetry in Rett syndrome. PROCEDURES Infrared thermal images were acquired passively from 15 patients (mean age = 13.7 years, range 4-47) with clinical diagnoses of Rett. Images were acquired using a FLIR T400 infrared thermal camera (still images recorded at 5 Hz, resolution of 320 × 240 pixels, thermal sensitivity = 0.05 °C; capture session lasted approximately 3 minutes). The infrared thermal camera was orthogonal to the body part (hands, feet) and positioned approximately 1 meter from the skins surface. RESULTS There were large intraindividual left/right differences in temperature. Seven (47%) and eight (53%) patients had statistically significant (P <0.05) left/right asymmetries between hands (mean difference = 0.87 °C, standard deviation = 1.21) and feet (mean difference = 1.73 °C, standard deviation = 3.03), respectively. Coders were reliable (intraclass correlations 0.97-0.99) on temperatures and selection of anatomical regions of interest. CONCLUSIONS The degree of thermal asymmetry may reflect prolonged activity of the sympathetic nervous system and individual differences in sympathetic regulation. As clinical trials emerge and endpoints are considered, portable infrared thermal camera may provide one noninvasive means of evaluating changes in sympathetic regulation.

A Case-Controlled Investigation of Tactile Reactivity in Young Children with and without Global Developmental Delay.

Assessing tactile function among children with intellectual, motor, and communication impairments remains a clinical challenge. A case control design was used to test whether children with global developmental delays (GDD; n = 20) would be more/less reactive to a modified quantitative sensory test (mQST) compared to controls (n = 20). Reactivity was indexed by blinded behavioral coding across vocal, facial, and gross motor responses during the mQST. On average the children with GDD were significantly more reactive than controls to most tactile sensory modalities including light touch (p = .034), pin prick (p = .008), cool (p = .039), pressure (p = .037), and repeated von Frey (p = .003). The results suggest the mQST approach was feasible and highlights the GDD sample was more reactive than controls to a range of stimuli.

A case‐controlled comparison of postoperative analgesic dosing between girls with Rett syndrome and girls with and without developmental disability undergoing spinal fusion surgery

Rett syndrome is associated with severe motor and communicative impairment making optimal postoperative pain management a challenge. There are case reports documenting reduced postoperative analgesic requirement in Rett syndrome.

A Case-controlled Investigation of Pain Experience and Sensory Function in Neuronal Ceroid Lipofuscinosis

Objectives:This case-control study explored pain experience and expression among individuals with neuronal ceroid lipofuscinosis (NCL) through parental report, tactile sensory testing, and infrared thermography (IRT). Materials and Methods:Participants with NCL (n=8; M=14.8 y) and their unaffected siblings (n=8; M=23.5 y) were characterized in terms of pain response to a brief tactile sensory test (light touch, Von Frey monofilament). During sensory testing, behavioral expression was measured using the Battens Observational Pain Scale and infrared thermography (IRT) was used to quantify changes in skin/eye temperature. Results:Children with NCL experienced pain frequently and from multiple sources that negatively impacted their lives. Children with NCL were reactive to the sensory testing as indexed by significant increased IRT temperature change (P<0.001). Across combined sensory conditions, individuals with NCL were significantly more reactive (Battens Observational Pain Scale total score) to sensory testing compared with siblings (P<0.05). Similarly, IRT difference scores between sensory conditions revealed a significant increase in temperature for individuals with NCL compared with siblings (P<0.001). Discussion:Ongoing reported pain was a problem for the children with NCL in this sample. Increased pain expression during the repeated Von Frey filament suggests that the pathophysiology of the ongoing pain may be centrally mediated.