This report summarizes the 2010 AOSSM/NIH (American Orthopaedic Society for Sports Medicine/National Institutes of Health) U13 Post–Joint Injury Osteoarthritis II Conference to include the discussion concerning potential study cohorts, assessment considerations, and research priorities. There was strong consensus and enthusiasm for approaching the development of disease-modifying treatments for osteoarthritis through study of “pre-osteoarthritic” cohorts, particularly human subjects under 30 years of age following acute anterior cruciate ligament injuries. Clinical study of acute treatment strategies initiated within a few days after injury will need development of recruitment pathways and short-term proof-of-concept outcome measures that are specific to the intervention being studied. For example, measures of joint inflammation can be used in short-term prospective randomized controlled trials to determine whether an anti-inflammatory intervention was effective in decreasing early inflammation. These short-term clinical trials will need to be followed by longer-term evaluation of the clinical cohorts for joint and cartilage degeneration to determine if the acute intervention affected later development of osteoarthritis. Research priorities were identified in several disciplines, particularly regarding development and validation of quantitative imaging, biomechanics, and biomarker measures of joint structure, composition, and function that predict the accelerated development of osteoarthritis. Systematic study of posttraumatic osteoarthritis is anticipated to advance understanding and treatment of all forms of osteoarthritis.
