Treatment of Spondylolysisin Pediatric Patients.

A clinical trial comparing effectiveness of a soft spinal brace and a rigid thoracolumbar orthosis will be performed. Patients will choose the treatment method (patient preference). One option is to be treated, as what is known as a golden standard, with a hard thoracolumbar brace (Boston brace) worn daily for four months. The other option is to be treated with a soft spinal brace for four months. The soft brace we use in this study is DJO Global's Porostrap lumbar support. Both groups cease from sporting activities and get identical physiotherapy, where the aim is to strengthen abdominal and back muscles. After four month brace treatment we will have a control appointment where a CT-scan is taken to detect the bony healing of the pars interarticularis. Other follow-up appointments will be at 12 months and 24 months. Subjective healing is measured each time with SRS-24-score and Oswestry disability Index or pain drawing. During the last appointment, approximately 2 years after beginning of the study, a standing lateral thoracolumbar radiograph is taken to detect if the patient has developed spondylolisthesis. Trunk strength and spinal mobility is measured at follow-up visits (4 months, 12months, and 24months).

SRS-24 questionnaire is a translated and modified version of the Scoliosis Research Society-22 questionnaire. The two first questions measure the intensity of the pain (1 meaning no pain and 9 referring to the worst pain imagined). The remaining 22 questions have five alternatives from 1 (the worst option) to 5 (the best option) and they intend to measure the health-related quality of life. It has been well validated and proved reliable in investigating children with scoliosis quality of life (18).

Oswestry disability Index (ODI) is an index used to evaluate patients' back and lower extremity pain translated in Finnish or Swedish (19). It consists of ten questions and VAS-score. One question is about sexual life and that's why this questionnaire is used only for patients over 16 years old. Patients under 16 years old are asked to fill a pain drawing. This also includes VAS-score.

Visual analogue score (VAS) is a numeric pain distress scale from 0 to 10, where zero refers to "no pain" and ten to " unbearable pain". Patient draws his/her pain in a line from 0 to 10. During each appointment a patient is asked to describe their back pain and/or lower extremity pain in this scale as it is included in both pain drawing and ODI.

Trunk strength and spinal mobility tests are used to evaluate the effect of the use of the brace to the muscles and movement of the trunk. The centimeters with a tape measure from the fingertips on the thigh in side-bend are measured and we grade it abnormal, if the measurement is over 2 standard deviations under the mean of the Finnish reference values (20). Non-dynamometric trunk performance is measured with repetitive sit-up, arch-up and squatting tests. The result is graded from 1 (poor) to 5 (excellent). 1 refers to 1 standard deviation or more below the mean of the normal Finnish population values and 5 to 1 standard deviation or more above this mean (21).

In MRI, from the T2 spin-echo weighted images disc degeneration is graded based on Pfirrmann classification. Grade I refers to normal disc and grade V to most advanced disc degeneration. (22).

Computed tomography (CT) is widely used to diagnose spondylolysis and to detect healing of it. It shows bony healing and nonunion (12). A standing lateral thoracolumbar radiograph is taken at last follow-up visit to determine spondylolisthesis. This is understood as an indirect sign of failure of the treatment of the spondylolysis.