Complex sentence: Gait abnormality is also common in persons with nervous system affections such as Multiple sclerosis, Parkinson's disease, Alzheimer's disease, Myasthenia gravis among others; orthopedic corrective treatment such as lower extremity amputation, post-fracture, and arthroplasty (joint replacement).
Split into simpler sentences: Gait abnormality is also common in persons with nervous system affections such as Multiple sclerosis, Parkinson's disease, Alzheimer's disease, Myasthenia gravis among others. Orthopedic corrective treatments may also manifest into gait abnormality, such as lower extremity amputation, post-fracture, and arthroplasty (joint replacement).