Central core myopathies (CCMs) are a group of genetic muscle disorders characterized by muscle weakness and wasting. These conditions primarily affect the skeletal muscles, which are responsible for voluntary movements, causing difficulties in walking, running, and performing various physical activities.
The term "central core" refers to a unique histopathological finding observed in the affected muscles. It describes the presence of small areas devoid of oxidative enzyme activity in the central part of the muscle fibers, where the mitochondria are typically located. This characteristic central core appearance can be observed under a microscope and is the hallmark feature of these myopathies.
CCMs are caused by mutations in the RYR1 gene, which encodes a protein called ryanodine receptor type 1. This protein plays a crucial role in muscle contraction by regulating the release of calcium ions within the muscle cells. Mutations in the RYR1 gene disrupt the normal functioning of this protein, leading to impaired muscle contraction and the characteristic features of CCMs.
Symptoms of central core myopathies may vary widely among affected individuals. Common signs include muscle weakness, particularly in the hips and thighs, delayed motor development, and poor muscle tone. Some individuals may also experience joint stiffness, scoliosis (curvature of the spine), and respiratory difficulties.
Treatment for central core myopathies primarily focuses on managing the symptoms and complications associated with the disorder. This may involve physical therapy, assistive devices, and range of motion exercises to maintain muscle strength and flexibility. Additionally, regular monitoring by healthcare professionals is necessary to address any emerging concerns and provide appropriate support to enhance the quality of life for individuals living with these myopathies.
