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What should we think about or look at, in case of patella dislocation in children?
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Fig. 3: Nail patella syndrome (NPS) lower limb signs: hypoplasic and dislocated patella (central). Iliac horns
are bilateral accessory outgrowths consisting of cortex and medulla continuous with the iliac bone. They
are located at the site of attachment of the gluteus medius muscles and project posterolaterally. They are
asymptomatic, frequently palpable, and need not be treated. Iliac horns are the pathognomonic feature of
Nail-patella syndrome; they occur in approximately 80% of cases and are observed only in this condition.
Fig. 4: Nail patella
syndrome (NPS) upper
limb signs: Radial head
dislocation according to
Storen lign (in black) the
radial axis does not cut
the lateral condyle
epiphysis (left). Finger
nail involvement lessens
in the more ulnar-sided
rays, being more severe
in the thumb. The nail
changes may be limited
to triangular lunulae a
characteristic feature of
NPS (right).