Back Pain in a Child

Essentials

• Prolonged back pain in a child is usually caused by a structural defect.
• Severe back pain in a child less than 10 years of age is often caused by a tumour (e.g. osteoid osteoma), an infection or a systemic disease (leukaemia).
• Further examinations are warranted in prolonged back pain in a child when the pain causes abnormal gait or hampers physical activities.
• In a child over 10 years of age, careful clinical examination and plain x-ray of the lumbar spine are in most cases sufficient to exclude the ”unpleasant” diseases that cause low back pain and may require surgical treatment, e.g. extensive spondylolisthesis and bone tumours.

Strain-associated vertebral osteopathy

• Common in children and adolescents of all age groups who take physical exercise.
• Most commonly affects the L5 vertebra
• Associated with sports that include repeated back extensions, like apparatus gymnastics, figure skating and ballet dancing.
• Symptoms
  • Low back pain that is aggravated by strain and impairs movements
• Findings
  • Straightening of the lumbar lordosis due to the pain
  • Bending the back is painful, especially extension backwards.
  • Tenderness to palpation at the vertebral spinous process
  • Often muscle tightness in the backside of the thigh (sign of nerve root irritation)
  • When normal, a lateral x-ray view of the lumbar spine with the patient standing often is a sufficient radiological examination.
  • MRI study may reveal oedema in the cancellous bone at the pedicle or pars interarticularis of the vertebral arch - may be uni- or bilateral.
• Treatment
  • Restriction of the causative physical exercise for a defined period of time (2 months) - may be replaced by e.g. cycling and swimming
  • If the condition progresses to a stress fracture: exercise prohibition for 4 months
• Prognosis
  • Most children may return symptomless to their former sports.
  • In some cases, spondylolysis will probably develop, and a part of these patients will develop spondylolisthesis.

Spondylolysis

• Probably a sequela of a former strain-associated vertebral osteopathy
• X-ray shows a seam between the anterior and the posterior part of the vertebra (pars interarticularis; picture F1)
• There is no displacement of the vertebra.
• Treatment
  • Symptomless (incidental finding): no treatment
  • Painful
    • Fresh change (oedema in the cancellous bone in MRI): exercise prohibition for 4 months
    • Old change (sclerosis): symptomatic treatment
• The prognosis is moderately good: two thirds of fresh spondylolysis cases in children will ossify with exercise prohibition. Non-ossified spondylolysis is associated with more back pain due to exertion, but the majority manage well with symptomatic treatment.

Spondylolisthesis

• Incidentally found in 6% of symptomless military conscripts.
• Low back pain that may radiate in the thighs and is aggravated by exercise
• The clinical signs include
  • exaggerated lumbar lordosis that is located higher up than normal
  • sometimes scoliosis
  • palpable threshold between the spinous processes
  • muscle tightness at the back of the thighs (hamstring tightness)
  • in severe cases, neurological symptoms of radicular deficit.
• X-ray shows a vertebral shift in the lateral view
• Treatment: maximal strain (weight-lifting, gymnastics) should be avoided
• Follow-up: in a growing and symptomatic child, a standing lateral lumbar spine x-ray after 6 months to monitor slipping
• Bone-fusion surgery is indicated if
  • the patient has recurrent symptoms
  • the olisthesis exceeds 1/3 of the sagittal diameter of the vertebra.

Calvé's disease (vertebra plana)

• A rare disease of children aged 2-10 years with total collapse of a vertebra.
• Eosinophilic granuloma of the vertebra is the most common aetiology.
• Symptoms include general withdrawing behaviour due to pain, stiff-looking gait or complete refusal to walk.
• Findings include local tenderness and a prominent spinous process.
• ESR may be slightly increased, and leucocytosis is sometimes found.
• Differential diagnostics: tuberculosis, bacterial spondylodiscitis, other bone tumours
• On suspicion, refer the child to a hospital for further investigations (MRI and biopsy are always indicated).
• Spontaneous cure is usual.

Osteoid osteoma

• A rare benign bone tumour in children and adolescents, usually located in the posterior structures of a vertebra
• Symptoms include back pain especially in the evening and night, unrelated to exertion and effectively relieved by NSAIDs. Children often learn to ask their parents for a painkiller at bedtime.
• Findings may include pain associated with palpation of the spinous process of a single vertebra or painful scoliosis.
• Laboratory test results are normal.
• May appear as a sclerotic change on native X-ray, but the finding is confirmed by CT or MRI.
• Treatment is carried out by a radiofrequency procedure or surgery.

Spondylodiscitis

• Aseptic or caused by bacteria
• Vague difficulty in walking and sitting in a child below school age is a typical symptom.
• The diagnosis is based on painful movements of the spine and local tenderness on palpation over the vertebra.
• The child should be hospitalized for further investigations (MRI, biopsy).
• Bacterial spondylodiscitis requires intravenous antimicrobial treatment.

Juvenile intervertebral disc prolapse

• Age-related degeneration of the intervertebral disc may start as early as before the age of 10.
• The usual location of the prolapse is presacral.
• Symptoms and findings
  • Abnormal gait and painful forced position (scoliosis)
  • Lasègue test result is pathological.
  • Neurological symptoms of radicular deficit are usually not present.
• Treatment
  • In children, surgical treatment is required clearly more often than in adults.