Background Ankylosing spondylitis (AS) is a chronic inflammatory disease that primarily affects the spine, characterized by bone proliferation and increased rigidity. Its prevalence is estimated 0.05- 0.25% of the population, and usually affects men in the second or third decade of life. Is associated with vertebral and hips loss of bone mineral density (BMD) due to inflammation. Both changes in biomechanical properties of the spine as decreased BMD increased bone fragility. Prevalence of vertebral fractures in clinical literature varies between 10-17%, being increased compared to healthy individuals of the same age and sex.
Objectives An analysis of the presence of vertebral fractures in patients with AS and their possible relationship with various clinical, dietary and therapeutic factors is performed.
Methods Patients with AS were included according to modified New York criteria. In such patients collected epidemiological characteristics (age, gender), year of diagnosis, toxic habits, body mass index (BMI), acute phase reactants (ESR, CRP), disease activity (BASDAI), physical measures (Schöber and modified Schöber, chest expansion, lateral flexion, occiput-wall distance, swallow-wall, intermalleolar and cervical rotation), function (BASFI), bone densitometry and cervical, dorsal, lumbar spine and sacroiliac radiographs were performed, analyzing the presence of fractures according to Genant semiquantitative method. Patients on modifying drugs in BMD, as well as those with some associated metabolic bone disease were excluded.
Results 165 patients were included, with a predominance of males (110 vs 55). The mean age was 48 years and duration of illness of 13 years. 35 patients had a spinal fracture, which corresponds to 21.2%. The most commonly affected vertebra was T7 in the 38.3% of cases, followed by T8 (21.2%), T9 (14.1%) T6 and T11 (7.1% each). The most common type of fracture was moderate wedging (Genant grade 2). We found no statistically significant relationship with the presence of fractures and patients age, sex, smoking, enol, physical measurements or disease activity. Either with increase in acute phase reactants. The only relationship found was between fractures and bone mineral density at the lumbar spine (OR 23.5, 95% CI 1.199 to 463.114) in the first densitometry made at the beginning of the disease.
Conclusions The prevalence of fractures in our patients was higher than that found in the literature. Patients with AS and fractures tend to be older than those without fractures, but this relationship did not reach statistical significance. We just found statistically significant relationship between the presence of fractures and lumbar spine bone mineral density in the first densitometry performed at initial diagnosis of AS. The most frequently affected vertebra was T7 with moderate wedging (Genant grade 2).
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Disclosure of Interest : None declared