Jens Ivar Brox ^A1, Kjersti Storheim ^A2, Inger Holm ^A3, Astrid Friis ^A3, Olav Reikerås ^A1
A1 Department of Orthopaedic Surgery, Section for Back Surgery and Physical Medicine and Rehabilitation National Hospital Oslo
^A2 Norwegian University of Sports and Physical Education Oslo
^A3 Department of Physiotherapy National Hospital Oslo Norway
DOI: 10.1080/16501970410017738

Objective: To compare measures of disability, psychological factors, pain and physical performance in healthy controls, and patients with sub-acute and chronic low back pain. To evaluate the concept of the deconditioning syndrome and to explore factors that may contribute to chronicity. Design: Case-control study. Subjects: Three age- and gender-matched groups were included in the study; healthy controls (n =45), patients sick-listed 8-12 weeks (n =46) and patients with chronic low back pain on a waiting list for lumbar instrumented fusion (n =45). Methods: Measures of disability, pain, psychological factors, and physical performance were obtained from the 3 groups using validated measures. Results: Gender, age, body weight and height were not significantly different between the groups. Comparable scores were found for self-rated working ability, fear-avoidance beliefs for physical activity and aerobic capacity in the 2 patient groups. Oswestry Disability Index, pain, emotional distress, abdominal and back muscle endurance were significantly different between the 3 groups. Self-efficacy for pain and fear-avoidance beliefs for work was significantly different between the 2 patient groups. Conclusion: The results suggest a stepwise deterioration of impairment and disability from healthy controls to patients with chronic low back pain. Most variables distinguished between healthy controls and patients with sub-acute or chronic low back pain. Deconditioning was more related to psychophysical measures of abdominal and back muscle endurance than to cardiovascular fitness. Comparable scores for fear-avoidance and working ability in the 2 patient categories suggest that these factors appear at an early stage and contribute to the transition from acute to chronic low back pain.