II. Epidemiology

  1. Limb pain is common (7% of pediatric visits)
  2. Atraumatic Limp
    1. Incidence: 1.8 per 1000 children (ED presentations)
    2. More common in males (RR 1.7)
    3. Median age: 4.4 years old
    4. Fischer (1999) J Bone Joint Surg Br 81(6): 1029-34 [PubMed]

III. Causes

  1. See Causes of Limp in Children
  2. Transient Hip Tenosynovitis
    1. Causes acute non-Traumatic limp in >80% of limping presentations (age 3 to 8 years, mild pain)
    2. Limp that typically resolves with Ibuprofen without red flag findings
    3. Distinguish from septic hip (see Kocher Criteria; fever and will not bear weight)
  3. Pediatric Limp Differential Diagnosis includes serious conditions with high morbidity
    1. Septic Arthritis
    2. Osteomyelitis
    3. Slipped Capital Femoral Epiphysis
    4. Legg-Calve-Perthes
    5. Malignancy including Leukemia
    6. Referred pain from Acute Appendicitis, Testicular Torsion, Discitis

IV. Physiology

V. History

  1. Pain timing
    1. Acute onset
      1. Fracture, Musculoskeletal Injury
    2. Gradual onset
      1. Rheumatologic Disorders
      2. Stress Fracture
      3. Osteomyelitis
      4. Tumors
    3. Constant pain
      1. Tumor, Infection
    4. Intermittent rest pain or night pain
      1. Tumor
    5. Morning stiffness
      1. Rheumatologic Disorders, Stress Fracture
    6. Severe pain out of proportion to physical findings
      1. Compartment Syndrome (tibia, Humerus, or Forearm Fracture with tense swelling)
  2. Pain distribution
    1. Focal pain
      1. Infection, Fracture or tumor
    2. Radiating pain (especially burning pain)
      1. Neuropathic pain
    3. Migratory Joint Pain
      1. Acute Rheumatic Fever
      2. Gonococcal Arthritis
    4. Hip Pain
      1. No systemic symptoms
        1. Legg-Calve-Perthes Disease (ages 4-9 years old)
        2. Slipped Capital Femoral Epiphysis (ages 11-16 years old)
      2. Systemic symptoms (e.g. fever) with increased inflammatory markers
        1. Septic Arthritis, Transient Synovitis, pelvic Osteomyelitis
        2. Sacroiliitis
        3. Psoas abscess
    5. Bone pain or tenderness
      1. Osteomyelitis (increased inflammatory markers)
      2. Acute Leukemia (CBC abnormalities, Petechiae, pallor, Hepatosplenomegaly)
      3. Osteosarcoma or Ewing Sarcoma (night pain, mass)
  3. Modifying factors
    1. Better with activity
      1. Rheumatologic Conditions
    2. Worse with activity
      1. Overuse injury, Stress Fracture
    3. Associated with overuse
      1. Osteochondritis Dissecans
      2. Osgood-Schlatter Disease
      3. Jumper's Knee
      4. Chondromalacia Patellae
      5. Sever Disease
      6. Stress Fracture
  4. Associated findings
    1. Fever, weight loss, Night Sweats
      1. Cancer
      2. Osteomyelitis
      3. Rheumatologic Condition
      4. Septic Arthritis
    2. Hemarthrosis
      1. Bleeding Disorder (e.g. Hemophilia)
    3. Pharyngitis (preceding limp)
      1. Rheumatic Fever
    4. Neck Pain with fever, photophobia
      1. Meningitis
    5. Back pain or spinal tenderness
      1. Precaution
        1. Musculoskeletal back pain is rare in children (always consider serious causes)
      2. Discitis
      3. Vertebral Osteomyelitis
      4. Spinal cord tumors
      5. Abdominal referred pain
    6. Abdominal Pain
      1. Acute Abdomen (e.g. Appendicitis, psoas abscess)
      2. Neuroblastoma
    7. Diarrhea (preceding limp) as well as Conjunctivitis, Urethritis, Oligoarthritis
      1. Reactive Arthritis
    8. Urinary symptoms (may be associated with Vomiting)
      1. Pelvic disorder (e.g. pelvic abscess)
      2. Reactive Arthritis (Urethritis)
  5. Associated exposures, events and conditions
    1. Tick Bite
      1. Lyme Disease
    2. Trauma
      1. Fracture (e.g. Toddler's Fracture), Musculoskeletal Injury, Skin Foreign Body
    3. Sexual abuse or sexually active
      1. Gonococcal Arthritis, Reactive Arthritis

VI. Exam: Systemic Signs

  1. General
    1. Obesity
      1. Slipped Capital Femoral Epiphysis (SCFE)
  2. Eye
    1. See Ocular Manifestations of Rheumatologic Disease
  3. Abdomen
    1. Abdominal mass
      1. Neuroblastoma, psoas abscess
    2. Abdominal tenderness
      1. Appendicitis or psoas abscess (Psoas Sign positive)
      2. Ovarian pathology (includes young girls)
      3. Other Acute Abdominal Pain
    3. Hepatomegaly or Splenomegaly with Lymphadenopathy
      1. Cancer
      2. Rheumatologic Disorder
  4. Neurologic
    1. See Developmental Delay
    2. See Muscle Weakness in Children
  5. Skin
    1. See Cutaneous Signs of Rheumatic Disease
    2. Examine for obvious superficial infections (Cellulitis, Furuncle, Paronychia)
      1. Expose skin (esp. feet and between toes, buttocks, perineum)
      2. Examine regions of Trauma or chronic decubitus wounds (esp. Pelvis, ankle, foot)
    3. Skin warm, tender, red overlying joint
      1. Septic Arthritis
    4. Ecchymosis
      1. Nonaccidental Trauma
      2. Acute Leukemia
    5. Midline spinal skin changes (e.g. dermal sinus, midline Lipoma, sacral dimple)
      1. See Cutaneous Signs of Dysraphism
    6. Neurocutaneous Syndrome (e.g. Cafe-Au-Lait Macule)
      1. See Neurofibromatosis

VII. Exam: Gait

  1. See Gait Evaluation in Children
  2. Distinguish between painful (antalgic) and non-painful (nonantalgic) Abnormal Gait
  3. Antalgic Gait
    1. Reduced weight bearing on painful limb, decreases stance phase relative to swing phase
    2. Refusal to bear weight (esp. with limited range of motion, systemic symptoms, fever) may be Septic Arthritis
  4. Nonantalgic gait
    1. See Abnormal Gait
    2. See Lower Extremity Abnormality in Children
    3. Includes Steppage Gait, Trendelenburg Gait, Circumduction Gait, Equinus Gait
    4. Pain is absent and does not alter gait

VIII. Exam: General 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 Weakness or Atrophy
    1. Muscular atrophy
      1. Disuse atrophy or neurologic disorder
    2. Trunk and Proximal Lower Limb Weakness with compensatory Calf hypertrophy (or Gowers Sign)
      1. Muscular Dystrophy
    3. Weak resisted hip flexion and abduction
      1. Legg-Calve-Perthes Disease
  3. Bone Tenderness - General
    1. Bone Tumor (may present with palpable bone mass)
    2. Osteomyelitis (esp. over metaphysis regions)
    3. Fracture or bone Contusion
  4. Bone Tenderness - Specific points of tenderness
    1. Pelvic Spines at ASIS or AIIS (sartorius or rectus femoris avulsion Fracture)
    2. Tibial shaft point tenderness in age < 4 years (Toddler Fracture)
    3. Tibial tubercule in a teen (Osgood-Schlatter Disease)
    4. Posterior calcaneous tenderness (Sever Disease)
    5. Navicular Tenderness (Kohler Bone Disease)
  5. Spine
    1. Evaluate spinal flexion and extension
    2. Evaluate for Scoliosis, lumbar lordosis, thoracic kyphosis
  6. Joint Hypermobility
    1. Ehlers-Danlos Syndrome
    2. Other Hypermobility Syndrome

IX. Exam: Hip and Pelvis

  1. See Hip Exam
  2. See Hip Rotation Evaluation in Children
  3. See Hip Range of Motion
  4. Gluteal or thigh skin fold asymmetry
    1. Congenital Hip Dysplasia
  5. Galeazzi Sign
    1. Limb Length Discrepancy
  6. FABER Test or Pelvic Compression Test positive
    1. Sacroiliac Joint Disorder
  7. Trandelenburg Test positive
    1. Congenital Hip Dysplasia, weak hip adductors
  8. W-Sitting Position
    1. Associated with Femoral Anteversion
    2. Patient sits on floor with each heel adjacent to the ipsilateral hip
      1. Hips flexed and externally rotated
      2. Knees maximally flexed
  9. Hip resting position flexed and externally rotated
    1. Slipped Capital Femoral Epiphysis
      1. Hip unable to be abducted or internally rotated
    2. Hip Joint effusion
      1. Hip abducted
  10. Hip reduced range of motion (often held in flexion and external rotation) with fever (often more subtle in presentation)
    1. Transient Synovitis
      1. More painful near the endpoint of the hip motion path
    2. Septic Arthritis of the hip
      1. Often painful throughout Hip Range of Motion path
  11. Hip internal rotation lost and painful (abduction may also cause pain)
    1. General
      1. Evaluate with patient prone with each knee flexed and rotated laterally
    2. Aseptic Necrosis of the Femoral Head
    3. Slipped Capital Femoral Epiphysis
    4. Legg-Calve-Perthes Disease
    5. Intraarticular hip disorder
  12. Hip abduction limited
    1. Developmental Dysplasia of the Hip
  13. Pelvic compression resulting in pain
    1. Sacroiliac joint disorder
    2. Pelvis Trauma

X. Exam: Leg

XI. 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
      3. Culture positive in 50-80% of aspirates (most commonly positive for Staphylococcus aureus)
      4. Synovial WBC Count >50,000 with PMNs >75%
    2. Complete Blood Count with Platelets and differential
    3. Erythrocyte Sedimentation Rate (ESR)
    4. C-Reactive Protein (C-RP)
    5. Blood Culture
    6. Procalcitonin
      1. May help to differentiate Septic Arthritis from non-infectious causes
      2. Zhao (2017) Am J Emerg Med 35(8): 1166-71 [PubMed]
  2. Other labs to consider
    1. Comprehensive metabolic panel
      1. Indicated in infection, comorbidity, complex or chronic presentations
    2. Reticulocyte Count
      1. Indicated in Hemoglobinopathy (esp. Sickle Cell Anemia)
      2. Evaluates for aplastic crisis
    3. ASO Titer and/or Throat Culture
    4. Stool Culture (for Reactive Arthritis, esp. SSCE culture for Shigella)
    5. Urethral or urine dna probe for Gonorrhea and Chlamydia (for Reactive Arthritis)
    6. Lyme Titer
      1. Only obtain if exposure history positive
    7. Antinuclear Antibody (ANA)
      1. Not recommended for routine screening in children with Joint Pain
      2. High False Positive in healthy children (10-40%)
      3. Consider positive if titer >1:160 or 1:320
      4. SLE diagnosis requires 3 additional criteria beyond positive ANA
    8. Rheumatoid Factor
      1. As with ANA, RF is non-specific and not recommended for routine screening in children

XII. Imaging

  1. XRay of region suspected of causing limp
    1. Consider bilateral lower extremity where source is not obvious from history or exam
      1. May include AP and lateral Tibia-Fibula and Femur XRays (consider Pelvis and foot as well)
      2. Tibia is by far the most common site of occult Leg Injury in non-weight bearing children
        1. Consider starting with tibia xray on involved side (or bilateral) and broaden evaluation as needed
    2. Consider imaging opposite side for comparison (esp. SCFE)
    3. Many injuries may be subtle and require close inspection, radiology over-read and additional views
      1. Internal Oblique view may be needed to visualize Toddler's Fracture
      2. Epiphyseal Fracture
      3. Buckle Fracture
    4. Hip XRays in children with limp should include frog-leg lateral view
      1. AP Pelvis commonly misses hip pathology in children including SCFE
      2. Some recommend not performing if acute Slipped Capital Femoral Epiphysis is suspected
        1. However, SCFE may be missed on other views
    5. Additional imaging in conditions with normal initial xrays (False Negative, esp. if periosteal reaction)
      1. Splinting or Casting with repeat XRay in 7-10 days
        1. Stress Fractures
        2. Toddler's Fracture
      2. Second-line imaging (see advanced imaging as below)
        1. Leg-Calve-Perthes Disease
        2. Osteomyelitis
        3. Septic Arthritis
  2. Ultrasound hip
    1. High Test Sensitivity for hip effusion but does not differentiate fluid causes
      1. Hip effusions with suspicion of Septic Arthritis require urgent Ultrasound guided aspiration
      2. Send aspirate for Gram Stain, cell count and culture
    2. Ultrasound may also evaluate other lesions
      1. Fractures
      2. Soft Tissue Masses including Soft Tissue Abscess
  3. Bone scan
    1. Not a first-line test in children due to radiation exposure risk and delay from injection to XRay
      1. See Radiation Exposure in Medical Procedures
    2. High Test Sensitivity for identifying occult causes of Pediatric Limp (entire body is imaged)
    3. Demonstrates occult Fracture, Stress Fracture, Osteomyelitis, tumor, metastases
    4. Findings are not specific for cause and requires further evaluation if positive
  4. Computed Tomography (CT)
    1. Not a first-line test in children due to radiation exposure risk
      1. See CT-associated Radiation Exposure
    2. Evaluates Cortical Bone
    3. May be used as alternative evaluation for infection or tumor, when MRI is unavailable
  5. Magnetic Resonance Imaging (MRI)
    1. Typically requires sedation in younger children
    2. Identifies most significant musculoskeletal conditions including Osteomyelitis, Septic Joint, and malignancy
    3. MRI Pelvis has broadest applicable imaging modality in the evaluation of the Limping Child
      1. May identify Stress Fracture, malignancy or pelvic organ pathology
      2. Identifies Osteomyelitis, septic Hip Arthritis (with contrast)

XIII. Evaluation: Red Flags distinguising organic from non-organic causes

  1. Red Flags suggestive of organic cause
    1. Pain on passive internal rotation
    2. Pain during both night and day
    3. Pain occurs on weekends and vacations
    4. Pain interrupts play and other pleasant activities
    5. Pain localized to joint
    6. Unilateral pain (red flag)
    7. Child limps or refuses to walk
    8. Pain fits with local anatomic explanation
    9. Concurrent signs and symptoms of systemic disease
    10. Acute onset in last 3 months
  2. Reassuring Findings suggestive of non-organic cause (e.g. Growing Pains, School Phobias)
    1. No pain on passive internal rotation
    2. Pain occurs only at night and on school days
    3. Pain does not interfere with normal activities
    4. Pain located between joints
    5. Bilateral symptoms
    6. Child is able to walk normally without a limp
    7. Pain pattern does not fit any recognizable anatomy
    8. Systemic signs and symptoms absent

XIV. Evaluation: Injury

XV. Evaluation: No systemic symptoms and no known injury

XVI. 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. See Transient Tenosynovitis of the Hip for protocol to distinguish from Septic Arthritis of the hip
    2. Joint Aspiration to differentiate Septic Arthritis from Transient Synovitis or Reactive Arthritis
      1. Especially if refuses weight bearing, fever >38.5 C (101.3 F), ESR >40 mm/h, WBC > 12k/mm3
      2. Kocher (2004) J Bone Joint Surg Am (8): 1629-35 +PMID:15292409 [PubMed]
    3. 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

XVII. Precautions: Pitfalls

  1. Always consider Nonaccidental Trauma in nonambulatory or developmentally delayed children with Fractures
  2. Limp is not always a lower extremity problem (consider back, hip and Pelvis causes)
  3. Hip Septic Arthritis findings (contrast with Toxic Synovitis) in cases of fever, Hip Pain and reduced range of motion
    1. See Toxic Synovitis for decision rules
  4. Vertebral Osteomyelitis findings (contrast with Diskitis) in children with fever, back pain and limp
    1. Persistent high fever
    2. Toxic appearance
    3. Back pain not limited to lumbar region
    4. Start with XRay spine, but MRI is most definitive modality
  5. Malignancy findings (contrast with Rheumatologic Conditions) in cases of fever, weight loss, Hepatomegaly, Arthritis
    1. Nonarticular bone pain or back pain
    2. Night Sweats
    3. Bruising
    4. Elevated Erythrocyte Sedimentation Rate, but normal to Low Platelet Count
    5. Low WBC Count, low-normal Platelet Count and night pain (ALL)
  6. Psoas abscess findings (contrast with Septic Arthritis) in cases of Abdominal Pain and Psoas Sign
    1. Flexing hip relieves pain and allows for painless internal and external range of motion
    2. Start with pelvic XRay (SI joint may be obscured) and pelvic Ultrasound
      1. MRI or CT Abdomen and Pelvis may be required

XVIII. Management: General

  1. See individual conditions for specific management
  2. Limp that responds to Ibuprofen with otherwise normal exam and no red flag findings
    1. More consistent with Transient Hip Tenosynovitis (>80% of Limping Child presentations)
    2. May be appropriate for close interval follow-up (days) after negative exam and xrays
      1. However, keep pitfalls (above) and Pediatric Limp Differential Diagnosis in mind
  3. Swelling or tenderness over open Growth Plate (physis)
    1. Immobilize regardless of imaging
    2. Disposition to clinic follow-up
  4. Urgent or emergent orthopedic Consultation
    1. Significantly angulated or displaced Fractures
    2. Intra-articular Fractures
    3. Septic Joint
    4. Neurovascular injury or Compartment Syndrome (emergent Consultation)
    5. Undiagnosed injury without ability to bear weight despite oral NSAIDs

Images: Related links to external sites (from Bing)

Related Studies