BACKGROUND: TTN is a complex gene with large genomic size and highly repetitive structure. Pathogenic variants in TTN have been reported to cause a range of skeletal muscle and cardiac disorders. Homozygous or compound heterozygous mutations tend to cause a wide spectrum of phenotypes with congenital or childhood onset. The onset and severity of the features were considered to be correlated with the types and location of the TTN variants.
METHODS: Whole-exome sequencing was performed on three unrelated families presenting with fetal akinesia deformation sequence (FADS), mainly characterized by reduced fetal movements and limb contractures. Sanger sequencing was performed to confirm the variants. RT-PCR analysis was performed.
RESULTS: TTN c.38,876-2 A > C, a meta transcript-only variant, with a second pathogenic or likely pathogenic variant in trans, was observed in five affected fetuses from the three families. Sanger sequencing showed that all the fetal variants were inherited from the parents. RT-PCR analysis showed two kinds of abnormal splicing, including intron 199 extension and skipping of 8 bases.
CONCLUSIONS: Here we report on three unrelated families presenting with FADS caused by four TTN variants. In addition, our study demonstrates that pathogenic meta transcript-only TTN variant can lead to defects which is recognizable prenatally in a recessive manner.

UNASSIGNED: To evaluate patients with arthrogryposis submitted to extensive surgical treatment with a minimum of 10 years of follow-up regarding the clinical and radiological aspects and the quality of life, using the 36-Item Short Form (SF-36) and the Disease-Specific Instrument (DSI).
UNASSIGNED: A retrospective study selected 33 patients, totaling 64 operated feet.
UNASSIGNED: The mean age of the patients was 17.9 years (12-39 years), and the mean follow-up time was 14.8 years (11-17). Amyoplasia represented 78.7% of syndromic diagnoses. Isolated posteromedial lateral release (PMLR) was performed in 21.8% of the feet, 27.2% of which required additional bone surgery, and about 50 feet (78.1%) were submitted to PMLR, lateral column shortening, and/or talectomy. In total, 46 talectomies were performed (71.8% of the feet), out of which 44 were the first procedure of choice. SF-36 questionnaire was evaluated and showed that 93.9% of the patients did not have restrictive and disabling pain, and the same percentage considered themselves as healthy and had good expectations for the future.
UNASSIGNED: Arthrogrypotic feet are difficult to treat, require many recurrent surgical procedures, and relapses are the rule. Stiffness is a common feature of these feet, and residual deformities were frequent. Level of Evidence IV; Case Series, Therapeutic Studies.
UNASSIGNED: Avaliar pacientes com artrogripose submetidos a tratamento cirúrgico convencional com um mínimo de 10 anos de seguimento quanto aos aspectos clínicos, radiológicos e qualidade de vida, utilizando o questionário de 36 itens Short Form 36 (SF-36) e o Instrumento específico de Doenças (IED).
UNASSIGNED: No estudo retrospectivo foram avaliados 33 pacientes, totalizando 64 pés operados.
UNASSIGNED: A média de idade foi de 17,9 anos (12-39 anos), e o tempo médio do seguimento foi de 14,8 anos (11-17). A amioplasia representou 78,7% dos diagnósticos sindrômicos. A liberação posteromedial lateral isolada (LP MI) foi realizada em 21,8% dos pés, 27,2%, com cirurgia óssea adicional, e cerca de 50 pés (78,1%) foram submetidos a LPM (liberação póstero medial), encurtamento da coluna lateral e/ou talectomia. Foram realizadas 46 talectomias (71,8% dos pés), sendo em 44 o procedimento de primeira escolha. O questionário SF-36 evidneciou que 93,9% dos pacientes estavam sem dor restritiva e incapacitante, consideravam-se saudáveis, com boas expectativas para o futuro.
UNASSIGNED: Os pés artrogripóticos são de difícil tratamento, requerendo muitos procedimentos cirúrgicos recorrentes. A rigidez é uma característica comum desses pés e as deformidades residuais foram frequentes. Estudos futuros poderão mostrar se haverá diferença no resultado do tratamento desses pés aplicando a abordagem inicial atual, mais conservadora. Nível de Evidência: IV; Estudos Terapêuticos; Série de Casos.

Pathogenic variants in the FKBP10 gene lead to a spectrum of rare autosomal recessive phenotypes, including osteogenesis imperfecta (OI) Type XI, Bruck syndrome Type I (BS I), and the congenital arthrogryposis-like phenotype (AG), each with variable clinical manifestations that are crucial for diagnosis. This study analyzed the clinical-genetic characteristics of patients with these conditions, focusing on both known and newly identified FKBP10 variants. We examined data from 15 patients, presenting symptoms of OI and joint contractures. Diagnostic methods included genealogical analysis, clinical assessments, radiography, whole exome sequencing, and direct automated Sanger sequencing. We diagnosed 15 patients with phenotypes due to biallelic FKBP10 variants-4 with OI Type XI, 10 with BS I, and 1 with the AG-like phenotype-demonstrating polymorphism in disease severity. Ten pathogenic FKBP10 variants were identified, including three novel ones, c.1373C>T (p.Pro458Leu), c.21del (p.Pro7fs), and c.831_832insCG (p.Gly278Argfs), and a recurrent variant, c.831dup (p.Gly278Argfs). Variant c.1490G>A (p.Trp497Ter) was found in two unrelated patients, causing OI XI in one and BS I in the other. Additionally, two unrelated patients with BS I and epidermolysis bullosa shared identical homozygous FKBP10 and KRT14 variants. This observation illustrates the diversity of FKBP10-related pathology and the importance of considering the full spectrum of phenotypes in clinical diagnostics.

BACKGROUND: Arthrogryposis multiplex congenita (AMC) is a group of rare musculoskeletal conditions that is associated with complex healthcare needs and long-term follow up. The literature reports significant direct, indirect, and psychosocial costs for caregivers of children with neuromuscular conditions. Due to mobility limitations and frequent hospital visits, caring for a child with AMC is complex. Other challenges experienced by caregivers include financial strain, job changes, changes in interpersonal relationships and abandonment. This study was aimed at exploring the lived experience of caregivers of children with AMC.
METHODS: The present study is part of a larger global mixed methods study. In the initial quantitative aspect of the study, caregivers (n = 158) of children and youths with AMC (aged 0-21 years) responded to a cost of care survey on an electronic platform. Of the 158 participants, 13 caregivers then further consented to participate in the qualitative aspect of the study in which a 60-min semi-structured, individual interview was conducted remotely. Open-ended questions were developed to gain a deeper understanding of the direct and indirect costs of care, their impact on the caregivers\' lives and the quality of the care-giving experience. Interviews were transcribed, and a coding scheme was developed drawing from both the existing literature and the content of the interviews. A deductive and inductive thematic analysis was used to analyze the qualitative data using the NVivo® qualitative data analysis software.
CONCLUSIONS: Five themes describing the experiences of caregivers of children with AMC emerged from the analysis of the qualitative data: 1. Impact of the caregiving experience; 2. Cost of childcare; 3. Support system for care; 4. Managing and navigating care; 5. Supporting the child\'s growth and development. In addition to the results of the thematic analysis, specific recommendations shared by the caregivers included the need for support groups and provision of support to youths to prepare them for adolescence. These findings will inform resource allocation, policymaking, and support services for children with rare conditions, their caregivers and families.

This current case series adds to the spectrum of Arthrogryposis renal dysfunction cholestasis (ARC)-associated variants. Increased awareness and early genetic testing for ARC are suggested in cases with failure to thrive, renal tubular dysfunction, and rickets, even when the degree of cholestasis is mild. Prompt identification and intervention may improve the quality of life.

The primary objective of this study was to evaluate the prevalence of low femoral and lumbar spine bone mineral density (BMD) in adults with arthrogryposis multiplex congenita (AMC). We performed a retrospective cohort analysis of adults with AMC who were enrolled in the French Reference Center for AMC and in the Pediatric and Adult Registry for Arthrogryposis (PARART, NCT05673265). Patients who had undergone dual-energy X-ray absorptiometry (DXA) and/or vitamin D testing were included in the analysis. Fifty-one patients (mean age, 32.9 ± 12.6 years) were included; 46 had undergone DXA. Thirty-two (32/51, 62.7%) patients had Amyoplasia, and 19 (19/51, 37.3%) had other types of AMC (18 distal arthrogryposis, 1 Larsen). Six patients (6/42, 14.3%) had a lumbar BMD Z score less than - 2. The mean lumbar spine Z score (- 0.03 ± 1.6) was not significantly lower than the expected BMD Z score in the general population. Nine (9/40, 22.5%) and 10 (10/40, 25.0%) patients had femoral neck and total hip BMD Z scores less than - 2, respectively. The mean femoral neck (- 1.1 ± 1.1) and total hip (- 1.2 ± 1.2) BMD Z scores in patients with AMC were significantly lower than expected in the general population (p < 0.001). Femoral neck BMD correlated with height (rs = 0.39, p = 0.01), age (rs = - 0.315, p = 0.48); total hip BMD correlated with height (rs = 0.331, p = 0.04) and calcium levels (rs = 0.41, p = 0.04). Twenty-five patients (25/51, 49.0%) reported 39 fractures. Thirty-one (31/36, 86.1%) patients had 25-hydroxyvitamin D levels less than 75 nmol/l, and 6 (6/36, 16.7%) had 25-hydroxyvitamin D levels less than 75 nmol/l. Adults with AMC had lower hip BMD than expected for their age, and they more frequently showed vitamin D insufficiency. Screening for low BMD by DXA and adding vitamin D supplementation when vitamin D status is insufficient should be considered in adults with AMC, especially if there is a history of falls or fractures.

UNASSIGNED: Bilateral Sprengel deformities, mirror movements synkinesis, and arthrogryposis are described in different combinations in various syndromes but never together.
UNASSIGNED: We present a 12-year-old girl who presented with bilateral shoulder deformities and difficulty in coordination while writing. On examination, she was noted to have bilateral Sprengel deformities with flexion contractures of upper-limb joints and mirror movements of both upper and lower-limb joints.
UNASSIGNED: In the light of relevant literature, we may speculate that these three have a causal relation and even a genetic basis but further studies are needed to prove the same.

OBJECTIVE: Arthrogryposis multiplex congenita (AMC) consists of more than 400 conditions involving severe joint contractures of at least two or more body regions. Management of clubfoot in patients with AMC is notoriously challenging, with a higher likelihood of recurrence than idiopathic clubfoot, which can be treated using the Ponseti technique to avoid or delay more invasive procedures. The purpose of this study is to determine the utility of multiple serial casting as a treatment of clubfoot in AMC using Pirani scores as an objective measure of deformity.
METHODS: Pirani scores were retrospectively collected from 17 AMC patients with a total of 30 clubfeet and two years follow-up from initiation of treatment. Patients with a minimum of three casting series were included. Pre-treatment and post-treatment deformity scores were examined across casting series using analysis of variance (ANOVA) statistical analysis.
RESULTS: The first series pre-treatment Pirani score improved from 4.80±1.54 to 1.68±1.48 (p<0.001). The second series improved from 4.23±1.03 to 2.72±0.916 (p<0.001). The third series had the smallest improvement from 3.87±1.07 to 2.82±1.02 (p<0.001). Change in Pirani scores showed a significant decrease from the first series to the second (p=0.001) and third (p<0.001). In addition, the number of casting days was found to significantly affect the change in scores during the third series (p=0.038).
CONCLUSIONS: The Ponseti technique can improve clubfoot in AMC as measured by the Pirani score. Data shows that early intervention yields better results, with a diminished yet effective ability to elicit change over time.

Biallelic pathogenic variants in MADD lead to a very rare neurodevelopmental disorder which is phenotypically pleiotropic grossly ranging from severe neonatal hypotonia, failure to thrive, multiple organ dysfunction, and early lethality to a similar but milder phenotype with better survival. Here, we report 5 patients from 3 unrelated Egyptian families in whom 4 patients showed the severe end of the spectrum displaying neonatal respiratory distress, hypotonia and chronic diarrhea while one patient presented with the mild form displaying moderate intellectual disability and myopathy. In addition, we observed distal arthrogryposis and nonspecific structural brain anomalies in all our patients. Interestingly, cerebellar and brainstem hypoplasia were noted in one patient. Whole exome sequencing identified three novel homozygous variants in the MADD gene: two likely pathogenic [c.4321delC p.(Gln1441ArgfsTer46) and c.2620 C > T p.(Arg874Ter)] and one variant of uncertain significance (c.4307 G > A, p.Arg1436Gln). The variants segregated with the disease in all available family members. Our findings confirm that arthrogryposis, genital, cardiac and structural brain anomalies are manifestations of MADD which expand the spectrum of MADD-related neurodevelopmental disorder. Moreover, they further highlight the convergence of MADD variants on different organ systems leading to complex phenotypes.

BACKGROUND: The MYH3-associated myosinopathies comprise a spectrum of rare neuromuscular disorders mainly characterized by distal arthrogryposis with or without other features like pterygia and vertebrae fusion. CPSKF1B (contractures, pterygia, and spondylocarpotarsal fusion syndrome1B) is the only known autosomal recessiveMYH3-associated myosinopathy so far, with no more than two dozen cases being reported.
METHODS: A boy with CPSKF1B was recruited and subjected to a comprehensive clinical and imaging evaluation. Genetic detection with whole-exome sequencing (WES) was performed on the patient and extended family members to identify the causative variation. A series of in silico and in vitro investigations were carried out to verify the pathogenicity of the two variants of the identified compound heterozygous variation.
RESULTS: The patient exhibited moderate CPSKF1B symptoms including multiarticular contractures, webbed neck, and spondylocarpotarsal fusion. WES detected a compound heterozygous MYH3 variation consisting of two variants, namely NM_002470.4: c.3377A>G; p. (E1126G) and NM_002470.4: c.5161-2A>C. It was indicated that the NM_002470.4: c.3377A>G; p. (E1126G) variant mainly impaired the local hydrogen bond formation and impacted the TGF-B pathway, while the NM_002470.4: c.5161-2A>C variant could affect the normal splicing of pre-mRNA, resulting in the appearance of multiple abnormal transcripts.
CONCLUSIONS: The findings of this study expanded the mutation spectrum of CPSKF1B, provided an important basis for the counseling of the affected family, and also laid a foundation for the functional study of MYH3 mutations.