Differential Diagnosis for Leg Pain in Children

When evaluating leg pain in children, it's crucial to consider a wide range of potential causes due to the diversity of possible diagnoses. The differential diagnosis can be organized into the following categories:

• Single Most Likely Diagnosis

  • Growing Pains: This is the most common cause of leg pain in children, typically occurring in the calf or thigh. It's characterized by recurrent, bilateral leg pain that usually occurs at night and resolves by morning. The exact cause is unknown, but it's thought to be related to the growth and development of bones and muscles.

• Other Likely Diagnoses

  • Muscle Strains: Common in active children, muscle strains can cause leg pain due to overuse or injury.
  • Shin Splints: Medial tibial stress syndrome, or shin splints, is a common overuse injury in children who participate in sports, causing pain in the front or side of the lower leg.
  • Osgood-Schlatter Disease: A condition that causes knee pain in adolescents due to inflammation of the patellar tendon at its insertion on the tibia.
  • Sever's Disease: Also known as calcaneal apophysitis, it's a common cause of heel pain in children, especially during periods of rapid growth.

• Do Not Miss Diagnoses

  • Septic Arthritis: A bacterial infection within a joint, which is a medical emergency requiring prompt antibiotic treatment and possibly surgical intervention.
  • Osteomyelitis: A bone infection that can cause severe pain, fever, and swelling, requiring immediate antibiotic treatment.
  • Slipped Capital Femoral Epiphysis (SCFE): A condition where the ball at the upper end of the femur (thigh bone) slips out of place, more common in obese adolescents. It's a hip emergency that requires prompt surgical intervention.
  • Child Abuse: Non-accidental trauma should always be considered in the differential diagnosis of unexplained leg pain or injuries in children.

• Rare Diagnoses

  • Leukemia: Although rare, leukemia can present with bone pain, including leg pain, due to bone marrow infiltration.
  • Neuroblastoma: A type of cancer that can cause leg pain if it metastasizes to the bones.
  • Ehlers-Danlos Syndrome: A group of disorders that affect connective tissues supporting the skin, bones, blood vessels, and many other organs and tissues, which can lead to joint hypermobility and pain.
  • Fabry Disease: A genetic disorder that can cause pain in the hands and feet due to the accumulation of a particular type of fat in the body's cells.

Each of these diagnoses has distinct clinical features and requires a thorough history, physical examination, and sometimes additional diagnostic tests for accurate identification and management.