A Study of the Modified Quebec Task Force Classification of Chronic Low Back Pain with Regards to Activity Limitation, Global Percieved Effect, Sick Leave, and its Prognostic Implications

Abstract

Introduction The Quebec Task Force(QTF) on activity related spinal disorders was a group of experts in various fields brought together by the Quebec Worker's Health and Safety Commission. It formally recognized that clinicians couldnot reliably differentiate between different patho anatomic causes of low back pain(LBP). Classifying patients as described by the QTF has shown associated differences on several characteristics which showed increasing severity from category 1(local LBP) across the categories of LBP+radiation above knee (category 2), LBP+radiation below knee (category 3) to LBP+neurological signs (category 4). The objective of the study is to determine the prognostic significance of the QTF classification in patients with chronic LBP and to compare the efficacy of the chronic LBP rehabilitation protocol among various categories of QTF. Material and Methods Routine data was collected at the time of presentation to an outpatient department of a tertiary care center in India. After taking a detailed history and clinical examination, the pain severity is assessed by Low Back Pain Rating scale (LBPRS) and the activity limitation is assessed by Roland Morris Disability Questionnaire (RMDQ). The patients were advised treatment according to the common standard rehabilitation protocol. The patients were followed up every 6 weeks to check for the progression of symptoms clinically and for the compliance with the rehabilitation protocol. The patients were evaluated at 3 months and again at 6 months for Global Perceived Effect (GPE), activity limitation (RMDQ questionnaire) and sick leave status along with LBPRS. Results A total of 188 patients were included with 75% 3 month and 70% 6 month follow up.category 1 had the least and category 4 had the most severe activity limitation at all time points.Patients in category 4 improved the most at the end of 6 months with the common rahabilitation protocol.Patients in category 4 landed up more frequently in surgery compared with others. There were no significant differences in comparisions between category 2 and category 3 Conclusion Categorizing patients based on QTF classification has shown significant association with activity limitation. Prognosis of the patient's condition based on the symptoms at presentation can be roughly estimated using the QTF classification. However, differentiating patients based on radiating pain above or below the knee has no significant prognostic implications. It was found difficult to establish a diagnosis based on symptoms alone. Hence, targeted treatment based on the QTF classification may have a potential role in better management of patients with chronic LBP.