Complex sentence: There is no cure for PD, but medications, surgery and physical treatment can provide relief, and are much more effective than those available for other neurological disorders like Alzheimer's disease, motor neurone disease, the Parkinson plus syndromes and multiple sclerosis.
Split into simpler sentences: There is no cure for Parkinson's disease, but medications, surgery and physical treatment can provide relief. Available existing treatments for Parkinson's disease are much more effective than those available for other neurological disorders like Alzheimer's disease, motor neurone disease, the Parkinson plus syndromes and multiple sclerosis.