Examining the Association between Physical Fitness, Spinal Flexibility, Spinal Posture and Reported Back Pain in 6 To 8 Year Old Children

The prevalence of back pain raises from childhood to adolescence about 18-51%. Therefore, there is a need for early detection of risk factors of back pain. The present study aims to examine the association between physical fitness, spinal flexibility, spinal posture and back pain in primary school children. 395 first-graders of the Swiss canton Basel-Stadt (age 7.3 y (SD 0.4)) were examined in the present cross-sectional study. Body mass index, body fat and waist circumference were measured using standard protocols for children. Physical fitness was determined with a test battery consisting of a 20 m shuttle run test, jumping sidewards, 20 m sprints and beam balancing backwards. Spinal flexibility and spinal posture were assessed using the Spinal Mouse MediMouse® (Inclination of the pelvic tilt, the thoracic spine, the lumbar spine and the spinal inclination). Back pain was evaluated by means of a proxy-reported questionnaire.Children with high versus low spinal flexibility performed better in jumping sidewards (pelvic tilt: p<0.001, d=0.7; spinal inclination: p<0.001, d=0.8), 20 m sprint (pelvic tilt: p=0.03, d=0.4; spinal inclination: p=0.04, d=0.5) and balancing backwards (pelvic tilt: p=0.05, d=0.5; spinal inclination: p<0.001, d=0.8). Boys with a postural insufficiency at pelvic tilt and spinal inclination showed a lower performance in 20 m shuttle running (pelvic tilt: p=0.01, d=0.6; spinal inclination: p=0.04, d=0.5) compared to children with a posture, graded as normal. No association between physical fitness, spinal flexibility, spinal posture and back pain was observed (all p>0.1). A high physical fitness level is associated with a higher spinal flexibility in pelvic tilt and spinal inclination in young children. Postural insufficiency was observed in boys with a poor aerobic fitness.