Lihasheikkouden

Lihasheikkous is the condition characterized by a reduced ability to generate muscular force, which may affect one or more muscle groups. It is not the same as fatigue, stiffness, or impaired endurance, and it can be acute or chronic. The severity ranges from mild weakness to marked impairment of function.

Causes are diverse and are typically grouped into neurological, muscular, metabolic, systemic, and drug- or toxin-related categories. Neurological causes include peripheral neuropathies, motor neuron diseases, and disorders such as myasthenia gravis. Muscular causes encompass inflammatory myopathies and genetic muscular dystrophies. Metabolic and nutritional factors include hypothyroidism, vitamin D deficiency, electrolyte disturbances, and malnutrition or cachexia. Systemic illnesses such as diabetes or chronic kidney disease, aging-related sarcopenia, and medication effects (for example corticosteroids or certain statins) can also lead to lihasheikkous.

Symptoms and presentation vary with the underlying cause but commonly include difficulty with activities requiring strength (climbing stairs, rising from a chair, lifting objects), observable muscle wasting or asymmetry, and fatigue that worsens with activity. Some patients may notice weakness is proximal (hips and shoulders) rather than distal.

Diagnosis typically requires a combination of history and physical examination, graded muscle strength assessment (often using the Medical Research Council scale), and targeted laboratory tests. Investigations may include serum CK, thyroid and electrolyte panels, vitamin levels, autoimmune markers, electromyography and nerve conduction studies, imaging, and sometimes muscle biopsy or genetic testing to identify specific diseases.

Treatment focuses on the underlying cause and supportive care. Management may include physical therapy to preserve strength and function, nutritional optimization, correction of metabolic abnormalities, modification or discontinuation of offending medications, and disease-specific therapies such as immunosuppression for autoimmune etiologies or symptomatic treatments for neuromuscular conditions. Prognosis depends on the cause and response to therapy.