central core myopathy

Central core myopathy is a congenital muscle disorder that affects skeletal muscles, often presenting with muscle weakness and structural abnormalities. It is associated with changes in muscle fibers, including the formation of disorganized areas known as cores. Variability in severity is common, with some individuals experiencing mild symptoms and others more significant muscle weakness and skeletal involvement. The condition is rare, affecting approximately 1 to 9 people per million.

Individuals with central core myopathy typically present with characteristic muscle findings that are evident on microscopic examination. Nearly all affected individuals show central core regions in muscle fibers, nemaline bodies, centrally nucleated muscle fibers, delayed ability to walk, feeding difficulties, neonatal hypotonia, and increased variability in muscle fiber diameter. In addition, many experience muscle weakness and, in a substantial proportion, weakness of facial musculature. Other features such as motor delay, hyporeflexia, ankle flexion contractures, scoliosis, talipes, and a susceptibility to malignant hyperthermia may occur. Not all individuals experience all features, and severity varies considerably.

Central core myopathy is linked to alterations in the RYR1 gene, which encodes a key calcium channel protein important for muscle contraction. Multiple inheritance patterns have been reported for this condition, including autosomal dominant and autosomal recessive forms. This means that while some cases are passed down from an affected parent in a dominant manner, other instances arise when both parents contribute a mutated copy. Genetic counseling is recommended for affected families to understand the inheritance implications and to discuss family planning options.

Currently, management of central core myopathy focuses on supportive care and symptom management. As there are no specific foundational therapies or FDA‐approved treatments available for this condition, treatment is tailored to the individual using a multidisciplinary approach. Patients benefit from regular surveillance and a team of specialists who can address muscle weakness, skeletal abnormalities such as scoliosis or joint deformities, and potential complications like malignant hyperthermia. Genetic counseling is also recommended to help guide family planning and ongoing care decisions.

The course of central core myopathy varies considerably, with outcomes depending on the severity of muscle involvement and the presence of skeletal abnormalities. With current standards of care, many individuals adapt well and benefit from regular monitoring and multidisciplinary management. It is important to recognize that not all individuals will experience every symptom and that the overall quality of life can be improved with early intervention and tailored therapy. Outcomes described in medical literature continue to evolve as standards of care improve. Families often find it helpful to connect with specialists familiar with this condition and to seek genetic counseling for guidance on long-term management.

Several clinical trials are currently investigating new treatment approaches for central core myopathy. Individuals interested in clinical trials can search ClinicalTrials.gov or consult their care team regarding eligibility and ongoing research opportunities.