UNASSIGNED: Camptodactyly, clasped thumbs, and windblown hands are distinctive features of distal arthrogryposis (DA). Current therapeutic interventions often yield suboptimal effects, predisposing patients to relapses and complications. This study explicates a corrective approach involving a progressive extension brace for the management of DA and evaluates its clinical outcomes.
UNASSIGNED: Between 2015 and 2023, progressive extension braces were used in 32 DA patients, with an average follow-up of 4.8 years. Patients were stratified by age into four groups: 0-1, 1-3, 3-7, and above 7 years. The correction of camptodactyly was assessed based on the total active movement (TAM) of metacarpophalangeal joints (MPJ) and proximal interphalangeal joints (PIPJ), as well as the extensor lag of PIPJ. Clasped thumb correction was evaluated by measuring the thumb-to-index finger metacarpal angle (M1M2 angle) and the degree of deviation at the first MPJ (M1P1 angle). The quality of life for the children was measured using PedsQL 4.0, while parental satisfaction was gauged using the FACE questionnaire.
UNASSIGNED: Earlier intervention with a progressive extension brace yielded superior corrective results. Infants aged 0-1 year and toddlers aged 1-3 years achieved average TAM scores of 152° and 126° after correction; however, patients older than 3 years experienced a significant decrease in TAM with the same treatment. Infants and toddlers with DA showed improvement in the average extensor lag from 46° to 6°. The M1M2 angle increased from an average of 38° to 65°, with the M1P1 angle decreasing from an average of 43° to 5°. After the treatment, average PedsQL scores of 94.7 (parent-reported) and 89.3 (child-reported) were achieved. Among the 32 parents, 24 expressed high satisfaction, 5 expressed moderate satisfaction, and 3 expressed fair satisfaction.
UNASSIGNED: The early, progressive, and consistent use of an extension brace significantly improved joint mobility and corrected camptodactyly and clasped thumbs. It can be an effective approach to addressing hand deformities in patients with DA.

We report the clinical findings of congenital peripheral nerve hypoplasia in seven patients. All seven children presented with unilateral ulnar or median nerve palsy or both. They were assessed clinically, and nerve diameters were assessed with ultrasonography and compared with the contralateral limb. Nerve conduction studies were performed in five children, and the nerves were explored in the four children who presented with accompanying constriction bands. By ultrasonography, the mean diameter of the ulnar nerve was 63% and 29% when compared with the normal arm and forearm, respectively, and the mean diameter of the median nerve was 63% and 46%. Hypoplasia in the nerve was not confined to constriction points but occurred in the entire upper limb in all seven cases. These patients were followed for an average of 12 months (range 6 to 30). Despite neurolysis and surgical decompression in four patients, none of the nerve palsies had recovered. The clinical findings suggest that this condition cannot be explained by simple mechanical compression, and more extensive pathological changes in the involved upper limb are evident in this rare disease.Level of evidence: IV.

Papillorenal syndrome (PRS), an autosomal dominant inherited condition, is clinically featured by renal hypoplasia and optic nerve dysplasia. Based on current knowledge of genotype-phenotype correlations in PRS, mutations in the Paired box 2 (PAX2) gene have been recognized as a critical pathogenesis of typical renal and optic disease manifestations. However, little information is currently available on the skeletal abnormalities of PRS and the potential contribution of PAX2 mutations. Here, we present a case of a 10-year-old female PRS patient with the typical features of chronic renal failure and severe myopia, but was unexpectedly discovered camptodactyly of her left middle finger which affects the proximal interphalangeal joint. Pathologically, the camptodactyly was further indicated by radiology as a skeletal deformity, demonstrating a decline of bone mineral density and disappearance of joint space. Molecular diagnostics revealed a heterozygous mutation, 220_225dup, in the exon 3 of her PAX2 gene, which is de novo considering the lack of this mutation in her non-consanguineous parents. This mutation leads to duplication of glutamic acid at position 74 and tyrosine at position 75 in PAX2 protein, which may influence the DNA-binding function. Besides, the absence of Spalt like transcription factor 4 (SALL4) mutation excluded the diagnosis of acro-renal-ocular syndrome (AROS), of which clinical characteristics are similar to our patient\'s. This case unravels a previously unrecognized phenotype of camptodactyly due to a significant skeletal deformity of PRS with a heterogeneous PAX2 mutation of hexanucleotide duplication. This report challenges against the current belief of genotype-phenotype correlations in PRS.

Blau syndrome (BS) is a rare autosomal dominant autoinflammatory disease characterized by the clinical triad of dermatitis, arthritis, and uveitis. It is caused by mutations in nucleotide-binding oligomerization domain-containing protein-2 (NOD2) gene. BS has been widely reported in Caucasians but cases documented in China are scarce. We reported two Chinese families with BS, which were by far the two largest pedigrees in the Chinese population. We identified two unrelated families with BS. The phenotypes and genotypes of these patients were reviewed and compared with previous cohorts. The proband of the first family was a 32-year-old Chinese Han woman, who had dermatitis, polyarthritis, and intermittent fever since the age of 6, bilateral panuveitis since 12. During her disease course, she lost her vision and developed hand flexion contractures. The proband of the second family was a 36-year-old Chinese Han woman, who had dermatitis and bilateral panuveitis since the age of 7, persistent polyarthritis since 13. Additional 7 and 4 family members were affected in the first and second families, respectively, and pedigree analysis suggested autosomal dominant inheritance. Genetic testing in both families identified the heterozygous c.1000 C > T, R334W mutation in NOD2 gene. Only one patient had recurrent fever as an expanded manifestation beyond the classical triad. BS can occur in multiple ethnic groups including the Chinese Han population. Our 11 adult patients constituted the largest adult cohort of BS ever reported in China. Lack of recognition of BS led to a significant delay in diagnosis. A considerable percentage of patients did not demonstrate the full spectrum of the classical triad, further complicating the diagnosis.