What kind of specialist can treat muscle disorders?

Depends on the cause: The type of specialist for muscle disorders will depend on the type of disorder: muscle disorder from an injury would be an orthopedist or physiatrist, but a muscle disorder due to a neurological issue would see a neurologist. Start with your family doctor or internist to help you see the right person.

Neurologist: Neurologists diagnose and treat myopathies e.g. Muscular disorders. Neuromuscular specialists are mostly found at academic medical centers. For symptomatic treatments, orthopedists and physiatrists treat patients with myopathies.

Muscle disorders: While many different doctors can work on diagnosing a muscle "disorder", neurologists specialize in conditions that involve primary metabolic problems, and physiatrists (rehab doctors) typically specialize in treatments.