The child with a limp

KEY LITERATURE & REFERENCES! 


PEARLS! 

Limping is never normal. It suggests pain, weakness, or structural abnormality.

  • Here’s a great video to review a few types of abnormal gait, including antalgic, trendelenburg, and equinus. 

Always consider developmental milestones when assessing a child’s gait.  

    • Also remember that genu varum is physiologic until 2yo while genu valgum is common in 3-8yo kids. Normal adult alignment is typically attained around 8yo with a slight degree of valgus. 

Trauma is the most common cause of acute limp in any age. 

  • Toddler fractures are typically occult spiral/oblique distal tibia fractures that result from a minor twisting injury or fall, which is often unwitnessed or simply not recalled by family. Exam usually reveals no swelling or limb deformity, but the child either limps or refuses to walk. XR only becomes positive after 10-14 days once healing has begun. 
    • Note that midshaft tibial fractures are more common in NAT. 

The apophysis is the site where a tendon or ligament connects to a bone. There are many forms of apophysitis, which often results from an overuse injury in growing children, including Osgood-Schlatter disease. 

In septic arthritis of the hip, damage to the hip cartilage and femoral head’s blood supply begin within 6-12 hrs of infection onset and may be irreversible after 1-2 days, resulting in osteonecrosis, growth arrest, and even permanent loss of joint function. 

The majority of confirmed cases of Lyme disease occur in the summer months, but occur year-round.

  • Mono/oligoarthritis (90% of which involve the knee) is the most common manifestation of late disseminated Lyme disease, which occurs weeks to months after initial infection in the absence of appropriate initial treatment. 

Compartment syndrome presents differently in children compared to adults, often with the 3 A’s: increasing Analgesia requirement, Anxiety, and Agitation. 


QUESTIONS TO PONDER!

  • What causes of limping in children require emergent intervention? 
  • When would you consider ordering labs in a child presenting with a limp?
  • How would you expect a missed diagnosis of developmental dysplasia of the hip to present in an older child? 
  • How do we differentiate septic arthritis from transient synovitis? And what’s the difference between septic arthritis and osteomyelitis?
  • Children with septic arthritis of the hip tend to hold the affected hip in a flexed position with slight abduction and external rotation. Why? 
  • How do we distinguish SCFE from Legg-Calve-Perthes disease on XR?
  • What are some non-traumatic causes of knee effusions? 
  • Which neonatal reflex must first disappear in order for a child to start walking?