A ten-day-old male Malawian child was brought to the hospital
with swelling in his left knee. The child was apparently in good
health, with no evidence for TORCH infections. His parents brought
him to the radiology department, and films of both knees were taken
in AP projection. The clinical impression was congenital syphilis.
However, no significant radiographic findings were noticed in favor
of this diagnosis, and VDRL was negative. Additional views of the
chest, pelvis, ankles, wrists, elbows, and the skull were obtained.
What is the most likely diagnosis?
Radiological changes were noticed predominantly in the
metaphyses of the long bones. There were no signs of periosteal
reaction, and epiphyses were unaffected. The trunk and skull did
not show any obvious abnormal radiological findings.
An abdominal and cardiac ultrasound scan was performed, though
no significant cardiac or visceral anomaly was found.
Later, a blood and synovial fluid culture reported isolation of
staphylococcus aureue and a diagnosis of septic arthritis of the
knee joint was established. The patient responded very well to
cloxacillin given intravenously for seven days.
Both parents were normal and healthy. We did not find any
history of congenital anomalies in the family.
Metaphyseal dysostosis was first described by Jansen in 1934.
Subsequently, its meaning expanded to include all congenital
dysostotic bone disorders with major radiological manifestations at
the metaphyses. Metaphyseal dysplasia, metaphyseal dysostosis, and
metaphyseal chondrodysplasia are all synonymous. Classification
remains controversial and sometimes becomes complicated by patients
who, besides having a classical metaphyseal dysplasia, later
develop changes elsewhere. As a rule of thumb, though, the spine,
diaphyses, and epiphyses are unaffected in this group of
Because of variable etiology, as well as the finding of
graduation in manifestations, much confusion has centered around
acceptable methods of classification for this group of disorders.
Some common and well known groups follow:
Jansen's metaphyseal dysplasia A rare form with a striking
clinical and radiological picture. Few cases have been seen in the
perinatal period or in early infancy when radiological
manifestations are pronounced while clinical signs are mild or
absent. One particular manifestation, grossly irregular
mineralization, is seen in the metaphyses of tubular bones. The
differential diagnosis in very early life includes hypophosphatasia
and hyperparathyroidism, both of which can be evaluated by
appropriate laboratory examination. Later the condition can be
confused with rickets, and occasionally with enchondromatosis.
Transmission is by autosomal dominant inheritance.
-A milder and most common form of the disorder, it is characterized
by moderate but progressive shortening of stature, with bowed legs
and a waddling gait. The metaphyses of the long bones are cupped
and resemble rickets. Confusion in diagnosis may be resolved by
determination of calcium phosphorus and alkaline phosphatase levels
in blood. Genetically, transmission is autosomal dominant
Types named after Pena & Vaandrager
-These are intermediate forms less severe than Jansen's and more
severe than the Schmid type in severity. These sometimes are
confused with Ollier disease.
-Metaphyseal dysplasia associated with pancreatic insufficiency and
-This is synonymous with cartilage hair hypoplasia. It is a
syndrome which occurs in Amish families consisting of metaphyseal
lesions, dwarfism, and sparse hair. Causes of this bone disorder
are variable and uncertain; some suggest an immune defect is the
cause, while others are of the opinion that it is an intrinsic bone
Prepared by R. Khare, MBBS, MD, Senior Lecturer and Head of
Radiology, College of Medicine, Chichiri, Blantyre, Malawi, and
David J. Sartoris, Professor of Radiology, University of
California, San Diego, CA.