Growing pains

Growing pains are a common, benign, and self-limited noninflammatory musculoskeletal pain syndrome that affects children. The cause remains unknown. Although growing pains have no standardized definition or diagnostic criteria, they are typically characterized by bilateral nonarticular pain in the lower extremities that occurs late in the day or during the night. Pain is absent during the daytime and when active. Growing pains are a clinical diagnosis. Individuals with atypical symptoms, abnormal examination findings, and/or features of systemic illness should receive a diagnostic evaluation to exclude alternative diagnoses (e.g., overuse syndromes, anatomical abnormalities, infections, neoplasms). Management is supportive and consists of massage, heat therapy, and nonopioid oral analgesics. Most cases resolve spontaneously by adolescence.

• Unknown ^[1][2]
• No proven correlation with periods of rapid growth ^[1]

• Prevalence estimates vary. ^[2]
• Most commonly occurs between 3 and 12 years of age ^[1]

Epidemiological data refers to the US, unless otherwise specified.

Clinical features of growing pains

Pain is the defining feature of growing pains and is typically characterized by the following: ^[1][3]

• Intensity: mild to severe
• Location ^[3]
  • Bilateral ^[1]
  • Most commonly affects the lower extremities (e.g., shins, calves, thighs, popliteal fossae)
  • Nonarticular
• Timing
  • Episodic (lasts minutes to hours) ^[4]
  • Occurs in the evening or nighttime and may:
    • Manifest after increased physical exertion
    • Awaken the child from sleep, but resolve by morning
  • Absent during the day or when active

Pain that limits activity should raise suspicion for differential diagnoses of growing pain. ^[1]

Red flag features of growing pains ^[1][2]

Any of the following clinical features suggests a differential diagnosis of growing pains.

• Constitutional symptoms
• Early morning pain or stiffness
• Pain during physical activity
• Unilateral or focal pain
• Persistent or worsening pain
• Abnormal examination findings (e.g., joint swelling, weakness, tenderness, gait changes, inability to bear weight)

Approach ^[1][2]

• Perform a comprehensive history and physical examination to evaluate for:
  • Clinical features of growing pains
  • Differential diagnoses of growing pains
• Diagnose clinically if all of the following are met:
  • Consistent history
  • Normal physical examination
  • No red flag features of growing pains
• If growing pains cannot be diagnosed from clinical findings, evaluate for alternative causes with, e.g.,:
  • Diagnostic studies
  • Specialty referral

Growing pains are a clinical diagnosis. ^[1][2]

Laboratory and/or imaging are used to evaluate for suspected alternative causes. ^[1][2]

Diagnostic studies ^[1][2]

Laboratory and imaging studies are normal in children with growing pains. Based on clinical suspicion, obtain diagnostic studies to exclude alternative causes. ^[1][2]

• Laboratory studies
  • Systemic illness (e.g., inflammatory or infectious conditions)
    • CBC with differential
    • BMP
    • ESR or CRP
    • Suspected autoimmune arthropathy: ANA, anti-ds DNA, complement levels, urinalysis
  • Restless legs syndrome: CBC, iron studies
• Imaging: to evaluate for structural abnormalities, trauma, bone tumors, or infection
  • Initial: x-rays
  • Advanced imaging (e.g., MRI or bone scan): if x-rays are normal and there is a high level of clinical suspicion

• Overuse syndromes
  • Stress fracture
  • Apophysitis (e.g., Osgood-Schlatter disease, Sever disease)
• Anatomical abnormalities
  • Legg-Calvé-Perthes disease
  • Slipped capital femoral epiphysis
  • Developmental dysplasia of the hip
• Infection: osteomyelitis
• Neoplasms
  • Leukemia
  • Benign bone tumors, e.g., osteochondroma, chondroblastoma, osteoid osteoma
  • Malignant bone tumors, e.g.,: Ewing sarcoma, osteosarcoma
• Inflammatory and autoimmune conditions
  • Juvenile idiopathic inflammatory myopathy
  • Juvenile idiopathic arthritis
  • Systemic lupus erythematosus
• Neuromuscular
  • Restless legs syndrome
  • Progressive muscular dystrophies
• Hypermobility: Ehlers-Danlos syndrome

The differential diagnoses listed here are not exhaustive.

• Reassurance that growing pains: ^[2]
  • Are benign and self-limited
  • Typically, resolve spontaneously by adolescence
• Symptomatic pain relief ^[1]
  • Analgesics: acetaminophen, ibuprofen (see “Nonopioid oral analgesia in children” for dosing)
  • Massage
  • Heat therapy