Role of functional capacity assessment in disability evaluation.

Individuals presenting with pain frequently report associated disability. Both pain and disability are complex phenomena. The bio-psycho-social complexity of pain and the different systems of disability make the evaluation of disability a very difficult process. There is a significant mismatch between complaints of pain and pathological process, as pathology can be present without symptoms of pain. Similarly, the subjective complaints of pain are disassociated with objective identification of physical impairment. Finally, the relationship between objective impairment determination and its effects on functional capacities and disability does not have a one-to-one relationship. Patients with pain, especially those with chronic low back pain, have significant impact on healthcare costs and on societal costs due to associated disability. Patients, employers, legal professionals, and physicians alike, are involved in the disability system. Each person is interested in the determination of the functional capacities of the individual with pain, so that appropriate return to work planning can be initiated. Functional capacities assessment have gained in popularity and are frequently accepted by employers and insurance companies alike as an objective approach to assess an individual's functional abilities and potential limitations. This manuscript provides an overview of the complex nature of pain, disability, and the role of functional capacities assessment, as one of the many approaches in the medical determination of disability.