Mobi-C Cervical Disc Replacement for the Treatment of One- and Two-Level Cervical Degenerative Disc Disease: One-Site Analysis Participating in the US FDA Trial

Abstract

PURPOSE: To assess the prevalence of lumbar spine MR abnormalities in adolescent children presenting with atraumatic back pain and to evaluate the relationship between Body Mass Index (BMI) and lumbar disc disease in these children. STUDY DESIGN/SETTING: Metropolitan, academic medical center PATIENT SAMPLE: Adolescent children, age 12–20, from an ER and outpatient clinic population. OUTCOME MEASURES: Descriptive statistics and chi-square analysis of differences between populations. METHODS: 602 consecutive lumbar spine MRI examinations performed in children, ages 12–20, for evaluation of back pain at a University Children’s Hospital over a four-year period were retrospectively reviewed. Patients with scoliosis, tumor and trauma were excluded. Images were reviewed by a board-certified neuroradiologist, and the following criteria were assessed: presence of lumbar disc disease, presence of multi-level disease, nature of disc disease (one ormore of: disc desiccation, disc space narrowing, disc protrusion, disc bulge), facet joint disease, spondylolysis and spondylolisthesis. When available from the electronic medical record, patient height and weight were used to compute age-corrected (BMI) and weight-for-age quartiles were calculated. Descriptive statistics and chi-square analysis were used to evaluate the significance of between-group differences. RESULTS: 188 patients met inclusion criteria. Only 48% (91/188) of patients had a normal lumbar spineMRI. 52% (97/188) of patients had identifiable disease on lumbar spine MRI, of which 94% (91/97) showed lumbar disc disease. Six patients had non-disc related abnormalities, including 3 patients with isolated spondylolysis, two with isolated facet joint disease, and one with Scheurman’s khyphosis. Data were available to determine BMI in 108/188 patients. Among these patients, 49% (53/108) had BMI greater than the 75th percentile for age, and 51% (55/108)were below the 75th percentile. 41% of patients (44/108) were considered either clinically ‘‘obese’’ or ‘‘at risk for obesity’’, with BMI greater than 85% for age. Among patients with BMI greater than 85%, 64% (28/44) demonstrated MRI evidence of lumbar disc disease. Among patients with lower BMI, 44% (28/64) showed MR evidence of lumbar disc disease. There was a statistically significant higher incidence of lumbar disc disease between the highest quartile group and those with lower BMI (p50.0338). CONCLUSIONS: There is a high incidence of MR abnormalities of the lumbar spine in adolescent children presenting with back pain. There is a strong relationship between increased BMI in this population and the incidence of lumbar disc disease. This represents further evidence of end-organ damage associated childhood obesity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.