Pediatric Limp

1. See Also
   1. Causes of Limp in Children
   2. Abnormal Gait
   3. Gait Evaluation in Children
2. Epidemiology
   1. Limb pain is common (7% of pediatric visits)
3. Causes
   1. See Causes of Limp in Children
4. History
   1. Pain timing
      1. Acute onset: Fracture
      2. Gradual onset: Rheumatologic disorders, Stress Fracture, Osteomyelitis, tumors
      3. Constant pain: Tumor, Infection
      4. Intermittent rest or night pain: Tumor
   2. Pain characteristics
      1. Burning pain: Suggests neuropathic pain
   3. Pain distribution
      1. Focal pain: Infection, Fracture or tumor
      2. Radiating pain: Neuropathic pain
      3. Migratory joint pain: Rheumatic Fever, Gonococcal Arthritis
   4. Modifying factors
      1. Better with activity: Rheumatologic conditions
      2. Worse with activity: Overuse injury, Stress Fracture
   5. Associated findings
      1. Fever, weight loss, Night Sweats: Tumor, Osteomyelitis, Rheumatologic, Septic Joint
      2. Bleeding Disorder (e.g. Hemophilia): Hemarthrosis
      3. Pharyngitis (preceding limp): Rheumatic Fever
      4. Neck Pain with fever, photophobia: Meningitis
      5. Back pain: Diskitis, Vertebral Osteomyelitis, spinal cord tumors
      6. Abdominal Pain: Acute Abdomen (e.g. Appendicitis, psoas abscess), Neuroblastoma
      7. Diarrhea (preceding limp): Reactive Arthritis
   6. Associated events and conditions
      1. Tick bite: Lyme Disease
      2. Trauma: Fracture, joint injury
      3. Sexual abuse: Gonococcal Arthritis, Reactive Arthritis
5. Exam: Musculoskeletal
   1. Joint Inflammation (joint swelling, warmth, and painful range of motion)
      1. Inflammatory arthritis
      2. Septic Arthritis (non-weight bearing)
      3. Reactive Arthritis
   2. Muscle
      1. Muscular atrophy: Disuse atrophy or neurologic disorder
      2. Calf hypertrophy: Muscular Dystrophy
   3. Bone Tenderness
      1. Fracture or bone Contusion
      2. Bone Tumor (may present with palpable bone mass)
      3. Osteomyelitis
   4. Hip and Pelvis
      1. Gluteal or thigh skin fold asymmetry
         1. Congenital Hip dysplasia
      2. Galeazzi Sign
         1. Limb Length Discrepancy
      3. Faber Test or Pelvic Compression Test positive
         1. Sacroiliac Joint Disorder
      4. Trendelenburg Test positive
         1. Congenital Hip dysplasia
      5. Hip resting position flexed and externally rotated
         1. Slipped Capital Femoral Epiphysis (hip unable to be abducted or internally rotated)
         2. Hip Joint effusion (hip abducted)
      6. Hip internal rotation lost
         1. Aseptic Necrosis of the Femoral Head
         2. Slipped Capital Femoral Epiphysis
   5. Foot
      1. See Gait Evaluation in Children
6. Exam: Systemic Signs
   1. Abdomen
      1. Abdominal mass
         1. Neuroblastoma
      2. Abdominal tenderness
         1. Appendicitis or psoas abscess (Psoas Sign positive)
         2. Other Acute Abdominal Pain
      3. Hepatomegaly or Splenomegaly with Lymphadenopathy
         1. Cancer
         2. Rheumatologic disorder
   2. Eye
      1. See Ocular Manifestations of Rheumatologic Disease
   3. Skin
      1. See Cutaneous Signs of Rheumatic Disease
7. Labs
   1. Obtain in cases where infection (e.g. Septic Arthritis) is strongly considered
      1. Joint aspiration for Gram Stain, cell count and Synovial Fluid culture
         1. Hip aspiration is best done under ultrasound guidance (preferred) or fluoroscopy
         2. Blind hip aspiration carries risk of neurovascular injury
      2. Complete Blood Count with platelets and differential
      3. Erythrocyte Sedimentation Rate (ESR)
      4. C-Reactive Protein (C-RP)
      5. Blood Culture
   2. Other labs to consider
      1. ASO Titer and/or Throat Culture
      2. Stool Culture (for Reactive Arthritis)
      3. Urethral or urine dna probe for Gonorrhea and Chlamydia (for Reactive Arthritis)
      4. Lyme Titer
      5. Antinuclear Antibody (ANA)
8. Imaging
   1. XRay of region suspected of causing limp
      1. Hip XRays in children with limp should include frog-leg lateral view
         1. Exception: Do not perform this view if acute Slipped Capital Femoral Epiphysis is suspected
   2. Ultrasound hip
      1. High Test Sensitivity for fluid but does not differentiate fluid causes
      2. Hip effusions with suspicion of Septic Arthritis require immediate ultrasound guided aspiration
   3. Bone scan
      1. High Test Sensitivity for identifying occult causes of Pediatric Limp
      2. Findings are not specific for cause and requires further evaluation if positive
   4. Computed Tomography (CT)
      1. Evaluates Cortical Bone
   5. Magnetic Resonance Imaging (MRI)
      1. Broadest applicable imaging modality in the evaluation of the Limping Child
9. Evaluation: Injury
   1. Acute Injury
      1. Fracture, Toddler's Fracture or Soft Tissue Injury
      2. Skin foreign body
   2. Overuse Examples
      1. Sever Disease (Achilles tendon)
      2. Osgood Schlatter Disease (Knee)
      3. Osteochondritis Dissecans
      4. Stress Fracture
10. Evaluation: No systemic symptoms and no known injury
    1. Knee Pain
       1. Accessory navicular
       2. Discoid lateral meniscus
    2. Hip Pain
       1. Slipped Capital Femoral Epiphysis
       2. Aseptic Necrosis of the Femoral Head
11. Evaluation: Systemic symptoms and no known Injury
    1. Obtain diagnostics
       1. Complete Blood Count (CBC)
       2. Erythrocyte Sedimentation Rate (ESR)
       3. C-Reactive Protein (C-RP)
       4. Specific imaging based on evaluation
    2. Back pain
       1. Obtain MRI to evaluate for Vertebral Osteomyelitis or diskitis
    3. Hip Pain with increased acute phase reactants (C-RP, ESR or White Blood Cell count)
       1. Joint aspiration to differentiate Septic Arthritis from Transient Synovitis or Reactive Arthritis
       2. Examination
          1. Psoas Sign: Consider Appendicitis or psoas abscess (CT Abdomen or MRI)
          2. Pelvic Bone tenderness: Consider pelvic Osteomyelitis
          3. Positive Faber Test or tenderness over SI joint
             1. Consider Sacroiliac infection or Spondyloarthropathy
    4. Bone pain
       1. Increased acute phase reactants (C-RP, ESR or White Blood Cell count)
          1. Consider Osteomyelitis
       2. Night pain and palpable bony mass
          1. Consider bone tumor (e.g. Osteosarcoma or Ewing Sarcoma)
       3. Suppressed cell counts (Neutropenia, Anemia, Thrombocytopenia)
          1. Consider Leukemia
12. References
    1. Sawyer (2009) Am Fam Physician 79(3): 215-24
    2. Fischer (1999) J Bone Joint Surg Br 81(6): 1029-34
    3. Flynn (2001) J Am Acad Orthop Surg 9(2): 89-98