Caregiver descriptions of dystonia in cerebral palsy.

OBJECTIVE: To determine how caregivers describe dystonia in people with cerebral palsy (CP). METHODS: In this prospective cohort study, paper surveys were administered to caregivers between September 7, 2021 and October 28, 2021 during CP Center visits at a large tertiary care center. Caregivers were asked to describe involuntary movements triggered by voluntary movement or triggered by tactile stimulation in the people with CP they cared for. Their CP Center medical provider separately assessed people with CP for dystonia. Movement features described exclusively by caregivers of people with CP and dystonia were determined using conventional content analysis. RESULTS: 113 caregivers responded on behalf of 56 people with and 57 people without dystonia. If caregivers noted that both voluntary movement and tactile stimulation triggered involuntary movements, that had a 92% positive predictive value for a dystonia diagnosis. Movement features exclusively described in people with CP and dystonia included: (1) stiffening, tensing, or tightening (15% of respondents); (2) involvement of the head (10%), torso (5%), or feet (5%); and (3) triggers of stretching (12.5%), excitement (5%), or transfers (5%). INTERPRETATION: In addition to a thorough exam, asking caregivers of people with CP to describe involuntary movements triggered by voluntary movement or tactile stimulation may inform clinical dystonia diagnosis.

Upper Extremity Dystonia Features in People With Spastic Cerebral Palsy.

Background and Objectives: Dystonia in cerebral palsy (CP) is debilitating and common, but underdiagnosed, especially when coexistent with spasticity. With dedicated research-based assessment, dystonia is found in most people with spastic CP but is only clinically diagnosed in the minority. To begin addressing the high rates of dystonia underdiagnosis in this population, we determined the key feature experts use to assess upper extremity dystonia in people with spastic CP. Methods: In this prospective cohort study, 3 pediatric movement disorder specialists assessed upper extremity dystonia in neurologic examination videos of people with spastic CP and isolated periventricular leukomalacia (PVL) on brain MRI (i.e., those with a brain injury pattern typical for spastic CP). Dystonia severity was rated using the 10-point Global Dystonia Severity Rating Scale, first by each expert independently and then again after consensus-building discussion. Conventional content analysis of these discussions revealed salient features ("codes") that experts used to assess upper extremity dystonia. Code frequency distributions were compared between dystonia severity categories using χ2 tests. Results: We identified 96 people with spastic CP with isolated PVL on brain MRI seen in the St. Louis Children's Hospital CP Center between 2005 and 2018. Of them, 26 people were able and willing to be recorded while doing a standardized set of upper extremity examination maneuvers (age 4-25 years; 28% nonambulatory, 77% White). When assessing their videos, experts cited the "hand" less often and "shoulder" more often with increasing dystonia severity (p < 0.005, χ2 test). "Mirror movements" and the "hand open/close" examination maneuver were cited significantly more frequently in videos when experts were attempting to distinguish between no dystonia and mild dystonia (p < 0.005). Discussion: Expert clinicians use distinct movement features to assess upper extremity dystonia in people with spastic CP and PVL. Attention to involuntary shoulder (vs hand) movements can help gauge dystonia severity. Differentiation between mirror movements and dystonia, particularly during the hand open/close examination maneuver, may help identify mild dystonia. These results can help guide upper extremity dystonia assessment in people with spastic CP, thus potentially helping mitigate dystonia underdiagnosis.

Brain Region Size Differences Associated With Dystonia in People With Cerebral Palsy Born Premature.

BACKGROUND: Dystonia in cerebral palsy (CP) is classically associated with deep gray matter injury at term gestation, but the patterns of injury associated with dystonia following premature birth are unclear. We examined whether there were brain regional size differences associated with dystonia in people with CP born premature. METHODS: In this retrospective cohort study, we identified subjects with CP born premature (<37 weeks gestational age) seen at a tertiary care CP center between February 1, 2017, to February 1, 2021, who had T1-weighted brain magnetic resonance imaging (MRI) done between ages one and five years available in the clinical record. We measured the following on these brain MRI images per the 2013 Kidokoro criteria: interhemispheric distance, biparietal width, lateral ventricle diameter, transcerebellar diameter, deep gray matter area, and corpus callosum thickness. We then compared the sizes of these structures between those with and without dystonia correcting for gestational age at birth and gross motor functional ability (univariate general linear models). RESULTS: Fifty-five subjects met the inclusion and exclusion criteria. Interhemispheric distance was significantly greater in those with dystonia, suggesting decreased cortical volume (P = 0.005). There was no significant difference in the other measured structures between those with and without dystonia, including deep gray matter area. CONCLUSIONS: Increased interhemispheric distance, not measures of deep gray matter size, correlate with the presence of dystonia in people with CP born premature.

Chronic striatal cholinergic interneuron excitation induces clinically-relevant dystonic behavior in mice.

Dystonia is common, debilitating, often medically refractory, and difficult to diagnose. The gold standard for both clinical and mouse model dystonia evaluation is subjective assessment, ideally by expert consensus. However, this subjectivity makes translational quantification of clinically-relevant dystonia metrics across species nearly impossible. Many mouse models of genetic dystonias display abnormal striatal cholinergic interneuron excitation, but few display subjectively dystonic features. Therefore, whether striatal cholinergic interneuron pathology causes dystonia remains unknown. To address these critical limitations, we first demonstrate that objectively quantifiable leg adduction variability correlates with leg dystonia severity in people. We then show that chemogenetic excitation of striatal cholinergic interneurons in mice causes comparable leg adduction variability in mice. This clinically-relevant dystonic behavior in mice does not occur with acute excitation, but rather develops after 14 days of ongoing striatal cholinergic interneuron excitation. This requirement for prolonged excitation recapitulates the clinically observed phenomena of a delay between an inciting brain injury and subsequent dystonia manifestation and demonstrates a causative link between chronic striatal cholinergic interneuron excitation and clinically-relevant dystonic behavior in mice. Therefore, these results support targeting striatal ChIs for dystonia drug development and suggests early treatment in the window following injury but prior to dystonia onset. One Sentence Summary: Chronic excitation of dorsal striatal cholinergic interneuron causes clinically-relevant dystonic phenotypes in mice.

Under-recognition of leg dystonia in people with cerebral palsy.

Objective: To determine the rates of clinical under-documentation of leg dystonia in people with cerebral palsy (CP). Methods: In this prospective cohort study, we identified independently ambulatory people age 10-20yo with CP-associated spasticity seen in a tertiary care CP center between 1/1/20 to 11/4/21. Three pediatric movement disorders specialists assessed gait videos from these visits for leg dystonia using the Global Dystonia Rating Scale. We compared the gold standard expert consensus assessment for each patient with the clinical documentation of dystonia during a contemporaneous CP Center clinic visit and also with dystonia documentation longitudinally in their medical record. Results: Of 116 people with CP-associated spasticity assessed in this study, 70 were found to have leg dystonia in their gait videos. Only 13% of these 70 individuals (n=9/70) had leg dystonia documented in their contemporaneous CP Center clinic visit, even though they were assessed during this visit by clinicians well-trained in CP and dystonia assessment. Even with repeated assessment, only 54% (n=38/70) of these individuals had leg dystonia documented in their medical record. Conclusions: Leg dystonia is clinically under-documented in people with CP-associated spasticity, even when these people are evaluated by well-trained clinicians. Longitudinal evaluation and vigilance for leg dystonia is critical to address this diagnostic gap.

Traditional bone setting and trauma care in South-Eastern Chad.

Background: Traditional bonesetters are the main providers of fracture treatment and trauma care in much of Africa. However, there is a paucity of literature on bonesetters in Chad. Objectives: Our study sought to investigate Chadian bonesetter practices, their relationship to the community, and the complex local perspectives on trauma care in Am Timan, Chad. Methods: Thirty-three semi-structured interviews were conducted with community members, traditional bonesetters, and physicians in Am Timan using a constructivist grounded theory approach. Responses were coded, categorized, and compared within and across study populations to identify themes. Results: Most community members (n=25) interviewed preferred bonesetters for trauma care due to their affordability, continuity and convenience of care, and the community's fear of Western medical practices. Although the Chadian bonesetters' fracture management mirrored bonesetters in neighboring African countries, the Chadian bonesetters have a much wider scope of practice, including treatment for both medical and spiritual ailments. Both Jabari (n=6) and physicians (n=2) emphasized the need for more training and collaboration. Conclusion: As in much of Africa, bonesetters perform a major role in providing trauma care in Chad. Our research identifies an opportunity to maximize trauma care in Chad through dialogue, training, and collaboration between bonesetters and physicians.

Objective and Clinically Feasible Analysis of Diffusion MRI Data can Help Predict Dystonia After Neonatal Brain Injury.

BACKGROUND: Dystonia in cerebral palsy is debilitating but underdiagnosed precluding targeted treatment that is most effective if instituted early. Deep gray matter injury is associated with dystonic cerebral palsy but is difficult to quantify. Objective and clinically feasible identification of injury preceding dystonia could help determine the children at the highest risk for developing dystonia and thus facilitate early dystonia detection. METHODS: We examined brain magnetic resonance images from four- to five-day-old neonates after therapeutic hypothermia for hypoxic-ischemic encephalopathy at a tertiary care center. Apparent diffusion coefficient values in the striatum and thalamus were determined using a web-based viewer integrated with the electronic medical record (IBM iConnect Access). The notes of specialists in neonatal neurology, pediatric movement disorders, and pediatric cerebral palsy (physicians most familiar with motor phenotyping after neonatal brain injury) were screened for all subjects through age of five years for motor phenotype documentation. RESULTS: Striatal and thalamic apparent diffusion coefficient values significantly predicted dystonia with receiver operator characteristic areas under the curve of 0.862 (P = 0.0004) and 0.838 (P = 0.001), respectively (n = 50 subjects). Striatal apparent diffusion coefficient values less than 1.014 × 10-3 mm2/s provided 100% specificity and 70% sensitivity for dystonia. Thalamic apparent diffusion coefficient values less than 0.973 × 10-3 mm2/s provided 100% specificity and 80% sensitivity for dystonia. CONCLUSIONS: Lower striatal and thalamic apparent diffusion coefficient values predicted dystonia in four- to five-day-old neonates who underwent therapeutic hypothermia for hypoxic ischemic encephalopathy. Objective and clinically feasible neonatal brain imaging assessment could help increase vigilance for dystonia in cerebral palsy.

Hearing Loss in Mucopolysaccharidoses: Current Knowledge and Future Directions.

Mucopolysaccharidoses (MPS) are a group of lysosomal storage disorders caused by a deficiency of one of the enzymes involved in the degradation of glycosaminoglycans. Hearing loss is a common clinical presentation in MPS. This paper reviews the literature on hearing loss for each of the seven recognized subtypes of MPS. Hearing loss was found to be common in MPS I, II, III, IVA, VI, and VII, and absent from MPS IVB and MPS IX. MPS VI presents primarily with conductive hearing loss, while the other subtypes (MPS I, MPS II, MPS III, MPS IVA, and MPS VII) can present with any type of hearing loss (conductive, sensorineural, or mixed hearing loss). The sensorineural component develops as the disease progresses, but there is no consensus on the etiology of the sensorineural component. Enzyme replacement therapy (ERT) is the most common therapy utilized for MPS, but the effects of ERT on hearing function have been inconclusive. This review highlights a need for more comprehensive and multidisciplinary research on hearing function that includes behavioral testing, objective testing, and temporal bone imaging. This information would allow for better understanding of the progression and etiology of hearing loss. Owing to the prevalence of hearing loss in MPS, early diagnosis of hearing loss and annual comprehensive audiological evaluations are recommended.