Pediatrics Answers 437fracture in children and important to recognize early because of the risk of
injury to the arteries and nerves that pass through this area. Patients typically
present with pain, swelling, and decreased range of motion with the arm
held in adduction. Most fractures occur after a fall on an outstretched hand
with the distal humerus displacing posteriorly. Posterior fractures are clas-
sified in three categories. Type I fractures show only an increased anterior
fat pad sign and evidence of a posterior fat pad which is always pathologic,
although not specific for this condition. Type II fractures have an obvious
non displaced fracture. Type III show posterior displacement of the capitel-
lum and have no cortical contact between the fracture fragments. Types II
and III require reduction and fixation.
The most serious complication of supracondylar fractures is Volkmann
ischemic contracture.This occurs when high-pressure builds up in the
forearm compartments leading to a compartment syndrome. It can also be
caused by kinking of the brachial artery with subsequent ischemia if not
repaired. If the condition is not addressed, there is potential for permanent
damage to nerves and muscles of the forearm leading to contractures.
Patients who develop pain upon passive extension of the fingers, forearm
tenderness, or refuse to open the hand have a very high risk of developing
this condition.
Ulnar nerve injury (c)is rare in supracondylar fractures. The most
commonly injured nerve is the anterior interosseous nerve. Brachial artery
transection(a)is uncommon and generally results in a pulse deficit on
examination. Malunion (b)and arthritis (d)are far less common and less
serious sequelae than the contractures.
398.The answer is b.(Fleischer and Ludwig, pp 1526-1527, 1545-1548.)
This is a Salter-Harris type IIfracture that involves the physis and meta-
physis.The physis or growth plate is a common site of fractures in pedi-
atric patients. Approximately 20% of fractures involve this area of active
bone growth with a peak incidence in early adolescence. The most widely
used system of classification for these fractures is the Salter-Harris classifi-
cation. In this system, there are five classifications of injuries. In general,
the higher the Salter-Harris classification, the worse the prognosis, and the
higher the chance for growth arrest. Salter-Harris Ioccurs when the frac-
ture involves the growth plate. There may be no radiographic evidence of
these fractures initially therefore you must have a high suspicion. This
injury should be suspected in any patient who is tender around the physis
of a bone even in the absence of obvious radiographic fracture. Treatment