Low back pain in not uncommon in children and adolescents.1-3 Although the prevalence of low back pain in children < 7 years is low, it increases with age, with studies reporting lifetime prevalence at age 12 years between 16% and 18% and rates as high as 66% by 16 years of age.4,5 Although children and adolescents usually have pain that is transient and benign without a defined cause, structural causes of low back pain should be considered in school-aged children with pain that persists for > 3 to 6 weeks. 4 The most common structural causes of adolescent low back pain are reviewed here.
Etiology: A mixed bag
Back pain in school-aged children is most commonly due to muscular strain, overuse, or poor posture. The pain is often transient in nature and responds to rest and postural education.4,6 A herniated disc is an uncommon finding in younger school-aged children, but incidence increases slightly among older adolescents, particularly those who are active in collision sports and/or weight-lifting.7,8 Pain caused by a herniated disc often radiates along the distribution of the sciatic nerve and worsens during lumbar flexion.
Spondylolysis and spondylolisthesis are important causes of back pain in children. Spondylolysis is defined as a defect or abnormality of the pars interarticularis and surrounding lamina and pedicle. Spondylolisthesis, which is less common, is defined as the translation or “slippage” of one vertebral segment in relation to the next caudal segment. These conditions commonly occur as a result of repetitive stress.
In a prospective study of adolescents < 19 years with low back pain for > 2 weeks, the prevalence of spondylolysis was 39.7%.9 Adolescent athletes with symptomatic low back pain are more likely to have spondylolysis than nonathletes (32% vs 2%, respectively).2,10 Pain is often made worse by extension of the spine. Spondylolysis and spondylolisthesis can be congenital or acquired, and both can be asymptomatic. Children and teens who are athletes are at higher risk for symptomatic spondylolysis and spondylolisthesis.10-12 This is especially true for those involved in gymnastics, dance, football, and/or volleyball, where a repetitive load is placed onto an extended spine.
Idiopathic scoliosis is an abnormal lateral curvature of the spine that usually develops during adolescence and worsens with growth. Historically, painful scoliosis was considered rare, but more recently researchers determined that children with scoliosis have a higher rate of pain compared to their peers.13,14 School-aged children with scoliosis were found to be at 2 times the risk of low back pain compared to those without scoliosis.13 It is important to identify scoliosis in adolescents so that progression can be monitored.
Screening for scoliosis in primary care is somewhat controversial. The US Preventive Services Task Force (USPSTF) finds insufficient evidence for screening asymptomatic adolescents for scoliosis.15 This recommendation is based on the fact that there is little evidence on the effect of screening on long-term outcomes. Screening may also lead to unnecessary radiation. Conversely, a position statement released by the Scoliosis Research Society, the Pediatric Orthopedic Society of North America, the American Association of Orthopedic Surgeons, and the American Academy of Pediatrics recommends scoliosis screening during routine pediatric office visits.16 Screening for girls is recommended at ages 10 and 12 years, and for boys, once between ages 13 and 14 years. The statement highlights evidence showing that focused screening by appropriate personnel has value in detecting a clinically significant curve (> 20°).
Scheuermann disease is a rare cause of back pain in children that usually develops during adolescence and results in increasing thoracic kyphosis. An autosomal dominant mutation plays a role in this disease of the growth cartilage endplate; repetitive strain on the growth cartilage is also a contributing factor.17,18 An atypical variant manifests with kyphosis in the thoracolumbar region.17
Continue to: Other causes of low back pain