Hip and knee osteoarthritis (OA) is an important health problem with a high prevalence and significant consequences on functional ability, perceived health, restriction of autonomy and handicap. The weight of multimorbidities and their interaction on functional ability and perceived health are left unexplored. This project will rely on the cohort KHOALA, representative, multiregional, of 881 prevalent cases (symptomatic hip and knee OA).

Main objective:

• to describe the evolution over time of pain, functional ability, social participation and quality of life in subjects with hip and knee OA
• to identify prognosis factors of disease evolution (socio-demographic, clinical, and other health parameters)
• to determine interactions with comorbidities, other personal and environmental factors (ICF model).

Concurrent objective: to improve measurement of perceived health specific to hip and knee OA by the OAKHQOL by improving its metrologic performances based on item response theory.

Task 1: To prepare an improved measurement scale, available as a judgment criteria for the 3rd year of cohort follow up, over the april 2010-march 2012 period, the mini-OAKHQOL Task 2: Evaluation of the cohort in 2010-2012 (year 3 of follow up) in a repeated measure design to best assess the evolution of perceived health and functional ability over time, and to identify stability of deterioration of autonomy. Perspectives: This project targets to provide public health deciders with information of good quality to help them manage determinants of perceived health in OA subjects, as essential factors to health care resource utilization in their various modalities.

Inclusion Criteria:

• hip or knee osteoarthritis (tibiofemoral), uni or bilateral, symptomatic, with confirmed diagnosis according to American College of Rheumatology ACR and European League Against Rheumatism (EULAR)
• Kellgren and Laurence radiological stage at least 2

Exclusion Criteria:

• knee or hip prosthesis on painful joint
• preceding osteotomy
• serious comorbidity (affecting quality of life, or leading to a high care consumption)
• according to X-ray : knee pain with isolated patello-femoral osteoarthritis (i.e without an associated tibiofemoral osteoarthritis)
• other pathology on knee or hip
• adults getting a legal protection or with the incapacity to give their consent

patient with hip or knee osteoarthritis