Are measures of function and disability important in low back care?

Currently, disablement due to low back syndrome (LBS) inflicts an extremely high cost to society, with yearly direct and indirect costs estimated in the billions of dollars. Patients with LBS often present a challenge for physical therapists trained in the evaluation of the physical nature of LBS. The psychosocial nature of a patient's complaint and the use of measures obtained from evaluation to guide patient management sometimes require interaction in a multidisciplinary environment. In this article, LBS will be discussed within the frameworks of Nagi's disablement pathway and an illness model described by Waddell. Both models suggest that to adequately treat LBS requires evaluation of the impairment, functional limitations, and disability using tools with adequate measurement characteristics. This article will focus on impairments and patient self-reports of quality of life and will discuss the relationship between impairments, functional limitations, and disability in LBS. Standardized quality of life measures are easily administered in everyday clinical settings and capture the patient's perceptions of the functional limitations and disability seen with LBS. Common self-reports are reviewed, and potential barriers to their use are discussed. Lacking an identifiable disease process in the majority of cases of LBS leaves most clinicians to deal with the impairments, functional limitations, and resultant disability. Physical therapists should, therefore, measure and gauge changes in all of these dimensions. To accomplish this, physical therapists must be willing to evaluate the dimensions of functional limitations and disabilities using tools that allow adherence to the same measurement standards (eg, reliability and validity) as those used to evaluate physical impairments.