A 51-year-old man
presents to the vascular surgery clinic for repair of an
iliac artery aneurysm that was incidentally discovered on
abdominal and pelvic CT (image to follow). The patient did
not have previous trauma that required surgical
intervention. Review of the rest of his medical history is
On physical examination, the patient's vital signs are
normal. In terms of general appearance, the patient is a
well-developed, well-nourished, tall, and thin man.
Respiratory examination yields normal findings, but the
chest examination reveals a tall, narrow thorax with
outward protrusion of the chest wall. Abdominal findings
are normal. Musculoskeletal examination reveals long, thin
fingers and toes. The patient has good (2+) pulses in the
bilateral dorsalis pedis and posterior tibial arteries.
Chest radiography is performed as part of the routine
preoperative evaluation (see Images 1-2).
What is the diagnosis?
Marfan syndrome: The frontal
and lateral radiographs (see Images 1-2) demonstrate
scoliosis of the thoracic spine and evidence of
previous orthopedic repair. The thorax is elongated
in the craniocaudal dimension, and the lateral
radiograph additionally demonstrates a striking
pectus carinatum, or pigeon chest, a deformity in
which the sternum is protruded in a convex shape.
Taken together, the skeletal abnormalities suggest
Marfan syndrome. This connective tissue disorder
primarily affects the skeleton, the cardiovascular
system, and the eye and occurs in 1-2 per 10,000
persons. Marfan syndrome is a primarily inherited
genetic defect with autosomal dominant transmission,
though approximately 30% of all cases result from
spontaneous mutations. Classic Marfan syndrome
results from mutations in the FBN1 locus on
the fibrillin gene on chromosome 15.
The skeletal manifestations of Marfan syndrome can
vary. Individuals with Marfan syndrome are
characteristically tall and thin, with limbs that
are disproportionately long in relation to their
trunk (dolichostenomelia). The patient's arm span
can be greater than his or her height.
Arachnodactyly is a classic finding on physical
examination and is defined as long fingers and toes
and chest deformities. Such deformities often
include pectus carinatum, or pectus excavatum, which
is funnel chest characterized by concave depression
of the sternum. Ligamentous laxity may result in pes
planus and angular deformities of the joints.
Scoliosis, or lateral curvature of the spine, may be
present as a result of the same mechanisms that
produce the pectus deformity.
Ocular abnormalities include ectopia lentis and a
displaced or malpositioned lens. The most common
ocular findings in Marfan syndrome are superior or
lateral dislocation, myopia, retinal detachment, and
cataracts. Cardiovascular manifestations are due to
cystic medial necrosis, which can result in
catastrophic aneurysm and/or dissection of the
aortic and pulmonary arteries. Insufficiency of the
aortic valve can result from aortic dilation. Mitral
valve disease with prolapse is also encountered.
In 1990, Flanagan et al first described the
association of iliac artery aneurysm with Marfan
syndrome. They postulated that the weakness of the
arterial tree caused by cystic medial necrosis is
more widespread than initially appreciated.
Savolainen et al (1993) later supported this
In the current patient, thrombus is present in an
aneurysm of the left common iliac artery. It
measures a maximum of 2.8 cm, as identified on the
contrast-enhanced CT scan of the abdomen and pelvis
(see Image 3). As a result of the extensive thrombus
in the aneurysm, the patient underwent open repair
rather than endoluminal graft placement. At the time
of this report, no complications occurred. Of
interest, CT scanning also revealed enlargement of
the dorsal aspect of the thecal sac (see Image 4) in
the lumbosacral region of the spine. Another major
diagnostic criterion of Marfan syndrome is a
dilated, CSF-filled area known as lumbosacral dural
Pectus deformities of the chest occur in
approximately 1 of 1000 of the general population,
they are more frequent in men than in women, and
they vary in severity. The cause of these disorders
is thought to be excessive growth of the costal
cartilages that results in inward or outward
buckling of the sternum. This buckling is often
noticeable at birth, but the characteristic chest
deformity manifests as the patient enters
adolescence. Many patients have additional asymmetry
and rotational deformity of the chest and sternum,
which may lead to scoliosis. Two conditions
associated with pectus deformities are Marfan
syndrome, as in this case, and Poland syndrome.
D, Kransdorf MJ. Bone and Joint Imaging. 3rd ed.
Philadelphia, Pa: Elsevier Saunders,
PV, Geoghegan J, Egan TJ. Iliac artery aneurysm
in Marfan's syndrome. Eur J Vasc Surg
H, Savola J, Savolainen A. Aneurysm of the iliac
artery in Marfan's syndrome. Ann Chir
K, Washington ER. eMedicine Journal [serial
online]. 2004. Available at: http://www.emedicine.com/orthoped/topic414.htm.
to further Information on:
more information regarding the genetics of Marfan syndrome,
including a full discussion of the major and minor
diagnostic criteria, see the eMedicine article Marfan
Syndrome (within the Orthopedic Surgery specialty).