contractures, pterygia, and variable skeletal fusions syndrome 1B

Contractures, pterygia, and variable skeletal fusions syndrome 1B is a congenital condition primarily affecting skeletal development, with characteristic joint contractures and vertebral fusions. Pathogenic variants in the MYH3 gene are implicated, leading to abnormal muscle and skeletal formation. It is inherited in an autosomal recessive manner, meaning affected individuals have received two altered copies of the gene. Precise prevalence data is not well established, and available care continues to evolve to address the range of physical manifestations.

The clinical presentation is marked by consistently present features such as flexion contractures, scoliosis, and fused thoracic vertebrae. In addition, many affected individuals exhibit variable features including webbed neck, absent phalangeal crease, short neck, and fused cervical vertebrae. Other findings, which occur less frequently, include tarsal synostosis, talipes equinovarus, antecubital pterygium, and cleft palate. Not all individuals experience all features, and severity varies considerably.

This condition is caused by pathogenic variants in the MYH3 gene, which plays a critical role in embryonic muscle and skeletal development. It is inherited in an autosomal recessive pattern, meaning that the condition develops when an individual inherits two copies of the altered gene, one from each parent. As a result, parents of an affected child may be carriers even though they do not show symptoms themselves. Genetic counseling is recommended to help families understand the inheritance pattern and assess recurrence risks for future offspring.

Currently, management focuses on supportive care and symptom relief, as there are no FDA-approved treatments specifically linked to contractures, pterygia, and variable skeletal fusions syndrome 1B. A multidisciplinary approach, including physical therapy, orthopedic management, and other supportive interventions, is often employed to address the musculoskeletal challenges. Patients should discuss treatment options with their healthcare team to determine the most appropriate strategies for their individual needs, and genetic counseling is advised for families.

Outcomes vary depending on the severity of symptoms, age at diagnosis, and access to specialized care. Many individuals benefit from advances in supportive treatments, although the condition may progress, stabilize, or follow a variable course over time. Outcomes described in medical literature continue to evolve as standards of care improve. Families often find it helpful to connect with genetic counselors and patient support groups for ongoing guidance and community support.