Linda Holmström

Hand function in relation to brain lesions and corticomotor-projection pattern in children with unilateral cerebral palsy

Aim  To investigate relationships between hand function, brain lesions, and corticomotor projections in children with unilateral cerebral palsy (CP).

Is outcome of constraint‐induced movement therapy in unilateral cerebral palsy dependent on corticomotor projection pattern and brain lesion characteristics?

The aim of the study was to explore individual variations in outcome of hand function after constraint‐induced movement therapy (CIMT) in relation to the organization of corticomotor projection and brain lesion characteristics in participants with unilateral cerebral palsy (CP).

Diffusion MRI in corticofugal fibers correlates with hand function in unilateral cerebral palsy

Diffusion MRI improves detection of abnormalities in white matter tracts in cerebral palsy (CP). Relationships between diffusion measurements and hand function are largely unexplored. We aimed first to assess microstructure of corticofugal fibers, and second to explore associations between tract injury as assessed by quantitative analysis of diffusion MRI and hand function in children with unilateral CP. Methods: In this cross-sectional study, 15 children with unilateral CP (6 boys, median age 12.4 years, min 7.2, max 17) and 24 controls were included (9 boys, median age 12.7 years, min 8.8, max 17.3). Hand function was assessed with the Box and Blocks (B&B) test. Magnetic resonance diffusion data (b value = 1,000 s/mm2, 45 directions) were collected on a 1.5-T scanner. Fractional anisotropy (FA), mean diffusivity (MD), and tensor eigenvalues were measured bilaterally in the cerebral peduncle (ROI1), the posterior limb of the internal capsule (PLIC, ROI2), and corticofugal fibers connecting these regions. Results: In children with CP, FA in both ROIs and the partial tract corresponding to the affected hand was significantly lower compared to controls. This was caused by an increase in diffusivity perpendicular to the tract. After controlling for age, mean FA contralateral to the affected hand correlated with B&B scores, which was independent of lesion type or number of voxels in the partial tract, cerebral peduncle, or PLIC. Conclusions: FA in corticofugal fibers is a sensitive marker of damage to the motor system and correlates with hand function in CP. Using FA may improve early prediction of outcome. Neurology® 2011;77:775–783

Evidence of validity in a new method for measurement of dexterity in children and adolescents

Aim  Many everyday activities involve manipulation of objects with the fingertips. Impaired performance in manipulative tasks is common in neurodevelopmental disorders. Thus accurate assessment of an individual’s ability to coordinate fingertip forces is important for planning treatment. We evaluated a recently developed assessment tool (the Strength–Dexterity Test), which is based on manipulation of unstable objects, in a paediatric population.

Insomnia in paediatric chronic pain and its impact on depression and functional disability

Children and adolescents attending health care due to chronic pain commonly presents with insomnia. Previous research suggests that problems with sleep are associated with depression and functional disability. However, more research is needed to clarify the relationship between pain, insomnia and disability.

A Clinical Pilot Study of Individual and Group Treatment for Adolescents with Chronic Pain and Their Parents: Effects of Acceptance and Commitment Therapy on Functioning.

Pediatric chronic pain is common and can result in substantial long-term disability. Previous studies on acceptance and commitment therapy (ACT) have shown promising results in improving functioning in affected children, but more research is still urgently needed. In the current clinical pilot study, we evaluated an ACT-based interdisciplinary outpatient intervention (14 sessions), including a parent support program (four sessions). Adolescents were referred to the clinic if they experienced disabling chronic pain. They were then randomized, along with their parents, to receive group (n = 12) or individual (n = 18) treatment. Adolescent pain interference, pain reactivity, depression, functional disability, pain intensity and psychological flexibility, along with parent anxiety, depression, pain reactivity and psychological flexibility were assessed using self-reported questionnaires. There were no significant differences in outcomes between individual and group treatment. Analyses illustrated significant (p < 0.01) improvements (medium to large effects) in pain interference, depression, pain reactivity and psychological flexibility post-treatment. Additionally, analyses showed significant (p < 0.01) improvements (large effects) in parent pain reactivity and psychological flexibility post-treatment. On all significant outcomes, clinically-significant changes were observed for 21%–63% of the adolescents across the different outcome measures and in 54%–76% of the parents. These results support previous findings and thus warrant the need for larger, randomized clinical trials evaluating the relative utility of individual and group treatment and the effects of parental interventions.

Advanced Fiber Tracking in Early Acquired Brain Injury Causing Cerebral Palsy

BACKGROUND AND PURPOSE: Diffusion-weighted MR imaging and fiber tractography can be used to investigate alterations in white matter tracts in patients with early acquired brain lesions and cerebral palsy. Most existing studies have used diffusion tensor tractography, which is limited in areas of complex fiber structures or pathologic processes. We explored a combined normalization and probabilistic fiber-tracking method for more realistic fiber tractography in this patient group. MATERIALS AND METHODS: This cross-sectional study included 17 children with unilateral cerebral palsy and 24 typically developing controls. DWI data were collected at 1.5T (45 directions, b=1000 s/mm2). Regions of interest were defined on a study-specific fractional anisotropy template and mapped onto subjects for fiber tracking. Probabilistic fiber tracking of the corticospinal tract and thalamic projections to the somatosensory cortex was performed by using constrained spherical deconvolution. Tracts were qualitatively assessed, and DTI parameters were extracted close to and distant from lesions and compared between groups. RESULTS: The corticospinal tract and thalamic projections to the somatosensory cortex were realistically reconstructed in both groups. Structural changes to tracts were seen in the cerebral palsy group and included splits, dislocations, compaction of the tracts, or failure to delineate the tract and were associated with underlying pathology seen on conventional MR imaging. Comparisons of DTI parameters indicated primary and secondary neurodegeneration along the corticospinal tract. Corticospinal tract and thalamic projections to the somatosensory cortex showed dissimilarities in both structural changes and DTI parameters. CONCLUSIONS: Our proposed method offers a sensitive means to explore alterations in WM tracts to further understand pathophysiologic changes following early acquired brain injury.

Evaluating the Statistical Properties of the Pain Interference Index in Children and Adolescents with Chronic Pain.

&NA; The high prevalence of chronic debilitating pain in pediatric populations calls for more knowledge regarding the impact of pain on functioning or pain interference. This in turn requires valid and reliable instruments to adequately assess the impact of pain on functioning. Also, adequate measures of pain interference are important in evaluations of behavioral interventions aimed at improving functioning. Objective: The objectives of this study were to evaluate the statistical properties of the Pain Interference Index (PII), including the factor structure, internal consistency, and concurrent criteria validity of the instrument. Method: Data were collected from a consecutive sample of children and adolescents referred to a tertiary pain clinic due to chronic pain (n = 163). A principal component analysis was used to investigate the latent factor structure of items. The internal consistency was assessed by Cronbachs alpha. A set of hierarchical regression analyses was conducted to evaluate the ability of instruments to predict levels of depression and functional disability. Results: Analyses indicated the adequacy of a 1-factor solution with a total of 6 items. The intercorrelation between items and the scales reliability was satisfactory. Furthermore, bivariate correlations and hierarchical regression analyses illustrate the concurrent criteria validity of the instrument. Conclusion: Results support the use of PII as an adequate instrument to assess pain interference in children and adolescents with chronic pain.

The Parent Psychological Flexibility Questionnaire (PPFQ): Item Reduction and Validation in a Clinical Sample of Swedish Parents of Children with Chronic Pain

In pediatric chronic pain, research indicates a positive relation between parental psychological flexibility (i.e., the parent’s willingness to experience distress related to the child’s pain in the service of valued behavior) and level of functioning in the child. This points to the utility of targeting parental psychological flexibility in pediatric chronic pain. The Parent Psychological Flexibility Questionnaire (PPFQ) is currently the only instrument developed for this purpose, and two previous studies have indicated its reliability and validity. The current study sought to validate the Swedish version of the 17-item PPFQ (PPFQ-17) in a sample of parents (n = 263) of children with chronic pain. Factor structure and internal reliability were evaluated by means of principal component analysis (PCA) and Cronbach’s alpha. Concurrent criterion validity was examined by hierarchical multiple regression analyses with parental anxiety and depression as outcomes. The PCA supported a three-factor solution with 10 items explaining 69.5% of the total variance. Cronbach’s alpha (0.86) indicated good internal consistency. The 10-item PPFQ (PPFQ-10) further explained a significant amount of variance in anxiety (29%), and depression (35.6%), confirming concurrent validity. In conclusion, results support the reliability and validity of the PPFQ-10, and suggest its usefulness in assessing psychological flexibility in parents of children with chronic pain.

A validation of the pain interference index in adults with long-standing pain.

Chronic pain is a major health problem and more knowledge is needed regarding the interference of pain on behaviors in different life domains. Clinically useful and statistically sound pain interference measures are highly important. Studies on youths have shown that the Pain Interference Index (PII) is a reliable and valid instrument that is sensitive to change following behavioral treatment. This measure may also have utility for adults, but no study has so far evaluated the statistical properties of the PII for long‐standing pain in adults.