What is the appropriate evaluation and management of bruising on a toddler's legs?

Evaluation and Management of Bruising on Toddler Legs

The approach to bruising on a toddler's legs depends critically on the child's age, mobility status, and bruise location—with bruising over bony prominences (knees, shins) in mobile children ≥12 months typically requiring no workup, while bruising in unusual locations or in non-mobile infants warrants comprehensive evaluation including consideration of skeletal survey and bleeding disorder assessment. 1

Initial Clinical Assessment

Complete a thorough history focusing on:

• Specific trauma history from caregivers and, if verbal, the child independently away from caregivers 1
• Developmental capabilities and mobility status (cruising, walking, running) 1
• Personal bleeding history: bleeding after circumcision, umbilical stump bleeding, excessive bleeding after dental procedures, epistaxis 1, 2
• Family history of bleeding disorders or specific ethnic populations with higher bleeding disorder rates 1, 2
• Medications and alternative therapies that may increase bleeding 1

Physical examination must include:

• Documentation of bruise location, pattern, and characteristics 1
• Examination of high-specificity abuse sites: buttocks, ears, genitals, torso, neck, cheek, eye area 1
• Assessment for patterned injuries (slap marks, object imprints, hand patterns) 1

Age and Location-Based Decision Algorithm

For Children ≥12 Months Old (Mobile Toddlers)

• Bruising on bony prominences alone (knees, shins, elbows): No further evaluation needed if history is consistent with normal play and falls 1
• Bruising on non-bony areas (cheek, ear, neck, upper arm, upper leg, hand, foot, torso, buttocks, genitals): Consider skeletal survey 1

For Infants <12 Months Old

• Any bruising in infants <6 months: Skeletal survey is necessary regardless of location, with rare exceptions 1
• Infants 6-12 months with bruising on: cheek, eye area, ear, neck, upper arm, upper leg, hand, foot, torso, buttock, or genital area—skeletal survey is necessary 1

When to Exclude Bleeding Disorder Workup

Laboratory evaluation for bleeding disorders is NOT needed when: 1

• Caregiver's trauma description sufficiently explains the bruising 1
• Child or independent witness provides history of trauma explaining the bruising 1
• Patterned bruising is present (slap marks, hand prints, object imprints) 1

When Bleeding Disorder Evaluation IS Indicated

Consider laboratory testing when: 1, 2

• History and physical examination do not adequately explain bruising pattern or severity 1
• Bruising in non-mobile infants at sites of normal handling or pressure 1
• Personal or family history suggestive of bleeding disorder 1, 2
• Extensive laboratory evaluation is NOT necessary in most situations given the rarity of bleeding disorders 1

Initial Laboratory Panel (if indicated)

Order based on prevalence and clinical presentation: 1, 2

• Complete blood count (CBC) with platelet count and morphology 2
• Prothrombin time (PT) 1, 2
• Activated partial thromboplastin time (aPTT) 1, 2
• Fibrinogen level 1, 2

Note: Von Willebrand disease and Factor XIII deficiency are NOT reliably detected by PT/aPTT screening 1. Mild hemophilia may not cause aPTT abnormalities but can still cause significant bleeding 1.

Critical Pitfalls to Avoid

• Do not assume bleeding disorder excludes abuse: Both conditions can coexist, and a follow-up evaluation after change in home setting can clarify if bleeding disorder truly explains findings 1, 2
• Avoid extensive testing for rare conditions before ruling out common disorders (prevalence >1 per 500,000) 2
• Recognize false-positive coagulation results: aPTT can be falsely prolonged with lupus anticoagulant or Factor XII deficiency (not true bleeding disorders), and traumatic brain injury causes transient coagulopathy 1
• Ensure proper specimen handling: Coagulation tests are extremely sensitive to handling errors leading to false-positives 1

When to Consult Specialists

• Pediatric hematologist: If preliminary testing suggests bleeding disorder, specific expanded testing needed, or testing for very rare conditions preferred 1, 2
• Child abuse pediatrician: Complex or concerning cases, especially non-mobile infants with unexplained bruising 1

Remember: The presence of bruising on toddler legs over bony prominences in a mobile child with appropriate developmental history is typically benign, but deviation from this pattern—particularly in younger, non-mobile children or unusual locations—demands systematic evaluation prioritizing child safety and appropriate medical assessment. 1