Multiple Osteochondromas Comorbid With Enlarged Parietal Foramina, Elongated Styloid Processes, and Tibiofibular Synostosis.

OBJECTIVES: This study investigates a unique case of multiple osteochondromas (MO) comorbid with enlarged parietal foramina and correlates the findings with the existing literature. The aim of this study is to provide a deeper understanding of anatomic variation for physicians. METHODS: A 66-year-old White male donor was examined during a routine cadaveric dissection performed by medical students in an anatomy laboratory. Detailed exploration of the skeleton and organs was performed, and photographs were taken. Tissue samples were obtained from multiple outgrowths, and histopathologic examination was done. RESULTS: Bilateral bony growths were noted rising from the long bones of the upper and lower extremities (femur, tibia, fibula, and radius). An accessory muscle was found to be associated with the left radial bony growth. Histopathologic examination was positive for osteochondroma. Inspection of the skull revealed enlarged parietal foramina. Other findings included tibiofibular synostosis, abnormally shaped vertebral bodies and ribs, and elongated styloid processes of the skull. CONCLUSIONS: In combination with the histopathologic examination, the case report and literature review elucidate a more precise clinical picture for those affected with MO or similar disorders. This report also emphasizes the necessity of further investigation of the pathogenesis of MO and Potocki-Shaffer syndrome.

Vertical transmission of a large calvarial ossification defect due to heterozygous variants of ALX4 and TWIST1.

ALX4 is a homeobox gene expressed in the mesenchyme of developing bone and is known to play an important role in the regulation of osteogenesis. Enlarged parietal foramina (EPF) is a phenotype of delayed intramembranous ossification of calvarial bones due to variants of ALX4. The contrasting phenotype of premature ossification of sutures is observed with heterozygous loss-of-function variants of TWIST1, which is an important regulator of osteoblast differentiation. Here, we describe an individual with a large cranium defect, with dominant transmission from the mother, both carrying disease causing heterozygous variants in ALX4 and TWIST1. The distinct phenotype of absent superior and posterior calvarium in the child and his mother was in sharp contrast to the other affected maternal relatives with a recognizable ALX4-related EPF phenotype. This report demonstrates comorbid disorders of Saethre-Chotzen syndrome and EPF in a mother and her child, resulting in severe skull defects reminiscent of calvarial abnormalities observed with bilallelic ALX4 variants. To our knowledge this is the first instance of ALX4 and TWIST1 variants acting synergistically to cause a unique phenotype influencing skull ossification.

Asymmetrically enlarged parietal foramina in a rare case of Goldenhar syndrome with a possible etiopathogenesis.

Goldenhar´s syndrome (GS) also known as oculo-auriculo-vertebral spectrum (OAVS) is a relatively rare condition. GS is of multifactorial etiology that includes environmental and/or genetic factors, in addition to teratogens that disturb the blastogenesis. A 5-year-old girl from Saudi Arabia, was a member of dizygotic twins conceived by assisted reproductive technology (ART), and born with features of GS. She had asymmetrical face, cleft lip and palate, right microphthalmia and microtia. Radiological imaging showed right maxillary and mandibular bone hypoplasia, asymmetrically enlarged parietal foramina, a persistent midline occipital foramen, abnormal bone arising from occipital bone, extending along tentorium cerebelli, and a lipoma at the right tentorium cerebelli. A rudimentary right eye with dermoid cyst and pseudotumor as well as bilateral atresia of external auditory canals were present. Karyotyping was normal. ART and the risk of manipulation of ovum/embryo, was shown to be associated with multiple gestation and an increased risk of major birth defects. Given that our patient was from Eastern-province close to the South of Iraq, where Gulf wars took place and the reported incidence of birth defects, including orofacial malformation, jumped there to about seven-folds, after war, thus, environmental contamination, and the possible teratogenic effect of depleted uranium could not be excluded. In conclusion, our case of GS, disclosed a rare radiological finding in calvarial anatomy, and asserted that, careful clinical evaluation is recommended in cases of GS. ART fertilization risk along with the possible parental environmental exposure were regarded as the potential cooperators of multifactorial etiology in our case.

Cranium Bifidum Occultum Associated with Hypertelorism Treated with Posterior Vault Reconstruction and Orbital Box Osteotomies: Case Report and Technical Note.

Cranium bifidum occultum is a disorder of skull ossification presenting as an enlarged posterior fontanelle in the upper posterior angle of the parietal bone near the intersection of the sagittal and lambdoid sutures. The standard treatment for cranium bifidum occultum is observation. We present a case of a 5-year-old boy who presented with a 15 × 4.5 cm midline posterior cranial vault defect consistent with diagnosis of cranium bifidum occultum associated with orbital hypertelorism and a widened nose. The patient underwent posterior vault reconstruction for correction of cranium bifidum occultum defect followed by bifrontal craniotomy and orbital box osteotomies for correction of orbital hypertelorism and nasal deformity. To our knowledge, this is the first reported case describing surgical treatment for cranium bifidum occultum associated with orbital hypertelorism.

Enlarged parietal foramina: a rare forensic autopsy finding.

Enlarged parietal foramina (EPF) are a quite rare developmental defect of the parietal bone which has to be distinguished from the normal small parietal foramina. We report a forensic case of an individual found in an advanced state of putrefaction in his own house with an undetermined cause of death. No evidence of trauma was observed, and the toxicological exam was negative. The victim was a 40-year-old man with a history of epilepsy. The large biparietal foramina, a rare anatomical variation and unusual autopsy finding, were observed at autopsy. The recognition of anatomical variations is important to avoid false interpretations and conclusions and has a significant potential as an identity factor, thus contributing to positive identification.

Enlarged parietal foramina presenting as scalp swelling in an infant

“Enlarged parietal foramina” is a congenital malformation with autosomal dominant inheritance. The condition is usually self-limiting and doesn’t require any treatment. However, it may also be associated with encephalocele, vascular anomalies or may be a part of syndrome. We present a case of enlarged parietal foramina in a child and discuss its imaging findings and the associated intracranial vascular malformations.