Posterior Lumbar Stress Reaction in Pediatric Patients. Treatment With or Without Soft Spinal Brace?

Inclusion Criteria: * Uni- or bilateral acute stress reaction of pars interarticularis or other part of posterior lumbar vertebra on MRI * No signs of fracture line on MRI or CT * Age between 8 and 18 years * Written informed consent * Low back pain Exclusion Criteria: * Spondylolysis * Spondylolisthesis * Systemic skeletal disorder (Osteogenesis imperfecta, skeletal dysplasia), osteoporosis * Systemic diseases (e.g. Diabetes mellitus type 1, rheumatic diseases, inflammatory bowel diseases, Marfan syndrome) * Other bony abnormalities seen on lumbar MRI examination (e.g. Scheuermann disease, L5 sacralisation, spina bifida)