Researchers at the University of Missouri-Columbia's Comparative Orthopaedic Laboratory said the model consists of small sections of joint capsule and cartilage typically discarded that mimics arthritic joints.

The scientists said their so-called joint in a test tube model can be used to investigate causes and mechanisms for the development and progression of arthritis and to screen new treatments such as pharmaceuticals.

The research team said the model has direct clinical implications for studying arthritis in dogs and humans.

The in vitro models allow for all normal joint tissue to be "grown" together in the same way they do in the actual joint. Researchers said the system maintains the tissues' appearance, composition and function so as to allow drugs, nutritional supplements and even exercise regimens to be tested on the in vitro model.

The study, led by Professor James Cook, was reported in the journal Current Rheumatology Reviews.