Osteoarthritis (OA) affects many aspects of life for affected individuals. Effective interventions to prevent and restore function must be based upon an understanding of what contributes to OA and its associated disabilities. A hypothetical OA disability model built upon the previous work of Nagi (1991), Verbrugge and Jette (1994), the International Classification of Functioning of World Health Organization (World Health Organization, 2001), and other scientific findings is proposed. The model includes a main disease pathway, which describes the sequence of events from OA-associated impairments to disabilities. Contextual factors influencing the process include individual characteristics, psychological state, coping style, comorbidities, social support, and physical environment. The model provides a useful conceptual framework for understanding the OA disability process from a biopsychosocial perspective and for guiding rehabilitation nursing interventions in OA care.