Chronic pain and mental health conditions after injury have an enormous impact on quality of life, placing a huge personal and financial burden on the individual, their families, as well as health and compensation systems. This observational prospective cohort study evaluated the role of demographic, injury/trauma, and compensation-related factors in chronic pain, mental health and disability after hospitalisation for orthopaedic injuries and major trauma in Victoria, Australia. We specifically sought to identify early predictors of complex needs, and to generate new evidence on the association between client experience of the compensation system and health outcomes.