Long-term physical disability changes how people move, sleep, work, communicate and participate in family life. Conventional rehabilitation remains essential, yet episodic clinic visits cannot fully capture daily fluctuations in fatigue, pain, balance, adherence or environmental barriers. This review synthesizes evidence published from 2020 to 2025 on smart rehabilitation monitoring systems that integrate wearable sensors, mobile applications, ambient sensing, cloud analytics and clinician dashboards to support patients with neurological, musculoskeletal, cardiopulmonary and mixed physical disabilities. Following the review model of Patel and colleagues, the paper moves from enabling technologies to clinical applications, but updates the discussion for artificial intelligence, consumer wearables, telerehabilitation safety, equity, privacy and quality-of-life outcomes. A structured narrative review method was applied using thematic screening around smart monitoring, telerehabilitation, wearables, physical disability, activities of daily living and quality of life. The synthesis shows that smart systems are most valuable when they do more than count steps: they translate motion and physiological signals into personalized feedback, early risk detection, shared decision-making and continuity between home and clinical services. Evidence is strongest for remote exercise delivery, gait and balance monitoring, fall-risk assessment, adherence support, and condition-specific rehabilitation in stroke, multiple sclerosis, spinal cord injury, vestibular disorders and musculoskeletal recovery. However, barriers remain in interoperability, algorithm transparency, reimbursement, digital literacy, long-term engagement and validation in diverse disability groups. The paper proposes an outcome-oriented framework in which sensing, analytics, feedback, safety governance and human coaching operate as a closed rehabilitation loop. Smart rehabilitation monitoring should therefore be positioned not as a replacement for therapists, but as a scalable care layer that can improve independence, participation, confidence and health-related quality of life for people living with long-term physical disabilities.