ACKNOWLEDGEMENTS The authors thank Sanofi-Aventis(r) for donating the medication for this study. Footnotes quality control Study conducted at LIM 41 – Laboratory of Medical Investigation of the Musculoskeletal System and in the Group of Osteometabolic and Degenerative Diseases of the Department of Orthopedics and Traumatology of the School of Medicine of Universidade de S?o Paulo. Citation: Zelada F, Almeida AM, Pailo AF, Bolliger Neto R, Okazaki E, Rezende MU. Viscosuplementation in patients with hemophilic arthropathy. Acta Ortop Bras. [online]. 2013;21(1):12-17. Available from URL: http://www.scielo.br/aob.
Chronic low back pain is one of the main complaints of patients with musculoskeletal disorders. It is defined by the presence of pain in the lumbar region lasting for more than 7-12 weeks.

1 It entails restriction of the capability for work, limitation for social activities, emotional problems 2 and reduced quality of life. 3 Chronic low back pain is frequently associated with depression. 4 Between 16.4 and 73.3% of the patients with chronic low back pain present depression. 5 The presence of depression is associated with the greater intensity and persistence of pain, 6 greater incapacity, 2 , 7 higher economic cost 2 and more adverse life events. The literature investigated did not produce any trials that were aimed at studying the impact of depression on the characteristics of chronic low back pain and on the fear of movement (kinesiophobia). The aim of the present study was to describe characteristics of pain, kinesiophobia and quality of life in patients with chronic low back pain associated with depression, in comparison to patients with chronic low back pain without depression.

METHOD This is a cross-sectional observational study, conducted in the outpatient physiotherapy section of a state government institution, on patients diagnosed with chronic low back pain. The study was carried out in the period from August 2008 to August 2009. The participants who agreed to take part in the study signed the informed consent form. The project was approved by the Institutional Review Bureau (Report no. 307/08). The inclusion criteria were: patients of both sexes, from 18 to 60 years of age, diagnosed with chronic low back pain at least three months previously.

Patients with neurological diseases (cerebrovascular accident, cerebral palsy and Parkinson’s disease), patients who had suffered any type of recent fracture, patients who were in a postoperative process of any nature, those with important acute diseases in physiotherapeutic treatment, AV-951 patients with chronic cancer pain and patients with chronic low back pain with nonmusculoskeletal causes were excluded. A total of 193 individuals, referred by orthopedists for outpatient physiotherapy treatment, were included in the study. The interviews were held by a single investigator, previously trained to apply the instruments.