The Temtamy-McKusick classification defines ulnar/postaxial polydactyly with a well-developed accessory digit as type A and cases with a rudimentary pedunculated digit as type B. Surgeons widely agree on type B treatment, but type A cases present more diverse phenotypes and reconstructive challenges. The authors developed an expanded classification based on radiographic morphology that may help guide surgical treatment. The multicenter cohort included all type A ulnar polydactyly cases in the Congenital Upper Limb Differences (CoULD) database and additional cases from the Children's Hospital of Philadelphia. Morphologic themes were determined from preoperative radiographs. Clinical relevance was evaluated by discussion and analysis of operative notes to confirm that each subtype carries distinct considerations for reconstruction. Four attending pediatric hand surgeons classified radiographs. Interrater and intrarater reliability were determined by the Cohen κ. The cohort included 125 type A hands from 84 patients (49% bilateral). Fifteen cases (18%) were syndromic and 37 (44%) reported a family history. Six subtypes emerged from radiographic analysis. Our classification is based on the proximal extent of the skeletal "duplication," comprising A1-hypoplastic, A2-phalangeal, A3-divergent metacarpophalangeal, A4-bifid metacarpal, A5-duplicated metacarpal, and A6-complex types. The authors propose a reconstructive plan for each subtype to aid surgical decision-making. Interrater and intrarater reliability were almost perfect. Raters agreed that all cases were classifiable, achieving 97% initial agreement. The CoULD Ulnar Polydactyly classification is feasible, comprehensive, and relevant to surgical management. The CoULD Study Group voted to adopt the classification after careful review, reinforcing its potential to frame the care pathway.

Objective: Craniofrontonasal syndrome (CFNS) is a rare X-linked disorder caused by EFNB1 pathogenic variants. It is characterized by coronal synostosis, facial asymmetry, hypertelorism, bifid nasal tip, woolly hair, longitudinal nail ridging, and skeletal anomalies in heterozygous females. Hemizygous males paradoxically display a less severe phenotype. This study aims to further define the clinical and mutational spectrum of CFNS in 8 new families. Materials and Methods: Nine female and 2 male patients were included. After detailed phenotypic characterization, Sanger sequencing of EFNB1 was performed, followed by deletion duplication analysis of mutation-negative patients. Results: Universal findings in affected females included wide nasal bridge, hypertelorism, and nasal tip abnormalities. Clinical features were consistent with literature data in the majority, except for 2 females with a mild phenotype resembling hemizygous males. Rare or previously undescribed features included enlarged cisterna magna, nasolacrimal duct obstruction, mesoaxial polydactyly, small echogenic kidney, and hypoplastic labia minora in females, and metopic groove, columellar skin pit, and absent midline mustache hair in males. Genetic analyses identified 6 EFNB1 variants, including a novel variant, heterozygous in females and hemizygous in males. One female patient with a classical CFNS phenotype had no identifiable EFNB1 variant. Conclusion: This study of the largest CFNS cohort from Türkiye expands the phenotypic spectrum in affected males and females and contributes to the genetic landscape of EFNB1 variants. Two females of the cohort with a phenotype at the mildest end of the CFNS spectrum emphasize the importance of recognizing atypical CFNS presentations for timely diagnosis and accurate genetic counseling.

To report a rare case of Desbuquois dysplasia Type 1 (DBQD1) diagnosed prenatally, caused by mutations in the CANT1 gene. DBQD1 is an autosomal recessive skeletal dysplasia with severe disproportionate dwarfism, joint laxity, and multiple skeletal anomalies. A 26-year-old woman, gravida 3, para 1, abortus 1, was referred due to short femur (FL) and humerus (HL) lengths on ultrasound. The patient and her husband are consanguineous. Ultrasound at our clinic revealed a hypoplastic thorax, severe limb anomalies, brachydactyly, overlapping fingers, clubfoot, and rocker-bottom feet, along with ventricular septal defects (VSDs). Genetic testing identified a homozygous pathogenic variant in the CANT1 gene (c.902_906dup, p.Ser303AlafsTer21). Both parents were heterozygous carriers. Following genetic counseling, the family opted for pregnancy termination. This case highlights the importance of comprehensive genetic testing and early, precise diagnosis for informed decision-making in managing rare skeletal dysplasias.

Ciliopathies are rare congenital disorders caused by defects in the structure or function of cilia, which can lead to a wide range of clinical manifestations. Among them, a subset known as skeletal ciliopathies exhibits significant phenotypic overlap and primarily affects skeletal development. This group includes several syndromes with overlapping but distinct clinical features, such as short-rib polydactyly syndrome (SRPS), Jeune asphyxiating thoracic dystrophy (JATD), Mainzer-Saldino syndrome (MZSDS), and cranioectodermal dysplasia (CED), also called Sensenbrenner syndrome. The most characterized features of skeletal ciliopathies are short stature, rhizomelic limb shortening, and thoracic narrowing to varying extents, with JATD presenting the most severe form. Here, we report a fetus with an extension of skeletal ciliopathy phenotype and compound heterozygous variants in the IFT140 gene. The affected fetus had multiple malformations, including increased nuchal transparency (NT), shortened and thick long bones, hypoplastic tibia and fibula, absence of bladder, flat nose, and frontal bossing. Our findings expand the mutation spectrum of IFT140, and the clinical spectrum associated with skeletal ciliopathies, highly relevant in diagnosis prenatal settings.

The pathophysiology of Patau's syndrome involves the triplication of chromosomes, leading to multiple comorbidities. An omphalocele is characterized by a protrusion of abdominal contents from the base of the umbilical cord through the peritoneum. An omphalomesenteric duct remnant occurs when there is a failure of duct closure that results in a diverticulum extending from the fetal midgut to the yolk sac. While congenital defects rarely occur simultaneously in patients with Patau's syndrome, this case report describes a newborn with Patau syndrome who presented with both an omphalocele and an omphalomesenteric duct remnant. The newborn exhibited various congenital abnormalities such as coloboma, microphthalmia, broad nasal bridge, cleft lip, cleft palate, low-set ears, systolic murmur, omphalocele, intestinal umbilical fistula (omphalomesenteric continuous vitelointestinal duct remnant), polydactyly, rocker-bottom feet, left-sided clubbed foot, and ruptured myelomeningocele. Imaging revealed additional complications such as a large patent ductus arteriosus, hypoplastic distal arch, markedly dilated right atrium and left ventricle, and cerebellar hypoplasia. Chromosomal analysis confirmed the diagnosis of Patau's syndrome. Given the untreatable medical condition, the patient was placed under "Do Not Resuscitate," and palliative care was initiated. The simultaneous appearance of an omphalocele and an omphalomesenteric continuous vitelointestinal duct is rare, and surgical intervention is the standard of care if the patient is deemed suitable for surgery. However, in cases where surgery is not feasible, palliative care is initiated. Regardless of the outcome, genetic counseling is essential and should include a discussion on paternal autonomy, understanding the disorder, suggesting alternative management methods, and making crucial decisions concerning future family care and planning. Ellis-van Creveld (EVC) syndrome is characterized by postaxial polydactyly of the hands, disproportionate short stature with short limbs, dystrophic and/or hypoplastic nails, dental and oral manifestations, congenital heart disease, and radiologic abnormalities (narrow chest, short ribs, short tubular bones, bulbous ends of the proximal ulnae and distal radii, carpal and metacarpal fusions, cone-shaped epiphyses of phalanges, small iliac crests, acetabular spur projections [trident ilia], and lateral slanting of the tibial plateau). Other less common and more variable features include postaxial polydactyly of the feet, upper lip defect, and developmental delay. The diagnosis of EVC syndrome is established in a proband with characteristic clinical and radiographic findings and biallelic pathogenic variants in DYNC2H1, DYNC2LI1, EVC, EVC2, GLI, SMO, or WDR35 or a heterozygous pathogenic variant in PRKACA or PRKACB identified by molecular genetic testing. Treatment of manifestations: Surgical amputation for polydactyly if desired; surgical correction of genu valgum as needed; physical therapy as needed; mechanical ventilation may be required in the neonatal period in those with severe restrictive lung disease; orthodontic and/or surgical treatment of dental anomalies; standard treatment for congenital heart disease; developmental services as needed; surgical correction of genital urinary malformations as needed; standard treatment for hearing loss. Surveillance: Monitor growth at least annually throughout childhood; orthopedic evaluation with radiographic assessment as needed; physical and rehabilitation medicine evaluation as needed; assessment for manifestations of respiratory failure and/or restrictive lung disease as needed; monitor for dental eruption, overcrowding, and dental morphology annually throughout childhood; echocardiogram as needed; monitor developmental progress and educational needs at each visit until adulthood; hearing evaluation as needed if hearing loss is present. Pregnancy management: Cesarean delivery is recommended in pregnant women with EVC syndrome who have pelvic/hip abnormalities. EVC syndrome caused by pathogenic variants in DYNC2H1, DYNC2LI1, EVC, EVC2, GLI, SMO, or WDR35 is inherited in an autosomal recessive manner. EVC syndrome caused by pathogenic variants in PRKACA or PRKACB (accounting for 2% of affected individuals) is inherited in an autosomal dominant manner. Autosomal recessive inheritance: If both parents are known to be heterozygous for an EVC syndrome-related pathogenic variant, each sib of an affected individual has at conception a 25% chance of being affected, a 50% chance of being heterozygous, and a 25% chance of inheriting neither of the familial pathogenic variants. Once the EVC syndrome-related pathogenic variants have been identified in an affected family member, carrier testing for at-risk relatives and prenatal and preimplantation genetic testing are possible.