Module 38, Pediatric Orthopaedist Level
A 14 year old Hispanic male presented to the emergency room after sustaining
a hyperextension injury to his right knee during a soccer collision. He
had the immediate onset of pain and noted swelling of the knee during the
first hour after injury. He was unable to bear weight; flexion and extension
of the knee exacerbated the pain. He had no previous history of injury
to his right lower extremity. Examination of the right lower extremity
was remarkable for a knee effusion with soft tissue swelling and diffuse
tenderness at the proximal tibia. The patient was unable to dorsiflex or
evert his foot. Sensation along the lateral calf and foot was diminished.
The dorsalis pedis and tibialis anterior pulses were palpable and there
was good distal capillary refill. AP and lateral views of the right lower
extremity revealed a Salter Harris III proximal tibial fracture with intraarticular
extension into the medial and lateral tibial plateaus. The epiphysis was
anteriorly displaced on the metaphysis. The patient underwent closed reduction
and application of a long leg splint on the night of injury. A palpable
dorsalis pedis pulse was present after reduction. The numbness was less
than when he presented. The patient presented again in the ER two days
after injury with complaints of weakness of toe movement and forefoot pain.
The splint was loosened. He was seen in follow-up clinic two days later
at which time he was found to have diffuse swelling from the mid thigh
distally, diminished sensation of the lateral foot, cyanosis of the dorsum
of the foot, fever to 101.5, and poorly Dopplerable pulses at the popliteal,
posterior tibial, and dorsalis pedis arteries.
Question 38A
An emergency arteriogram of the lower extremity is indicated.
Question 38B
An
external fixator frame should now be applied.
Question 38C
Measurements
of the compartments should be made to rule out increased compartmental
pressures.
Question 38D
He
underwent a venous duplex ultrasound of the right lower extremity to rule
deep venous thrombosis.
Question 38E
Although
weak, there was a definite posterior tibial artery pulse by Doppler, therefore
you can be assured that there is no major arterial injury.
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