Musculoskeletal pathology of the knee commonly occurs with aging and as a result of injury. Further, the incidence of anterior cruciate ligament injuries continues to increase annually, and may precede the eventual onset of osteoarthritis (OA), a debilitating and prevalent disease characterized by cartilage degeneration. Early detection of OA remains elusive, with current imaging methods lacking adequate sensitivity to detect early pathologic cartilage changes. Knowledge of the tissue molecular characteristics that correlate with the quality of the repair tissue and clinical outcome in repair procedures could greatly improve decision making during arthroscopic procedures. We are interested in development of mid- and near- infrared (IR) spectroscopic arthroscopic-based fiber-optic devices to assess cartilage, meniscus, tendons and ligaments. There is great potential for translation to clinical settings, particularly with the application of multivariate methods for data analysis, including cluster analysis, principal component analysis (PCA) and partial least squares (PLS) regression.