To The Editor:
We read with interest "Tibial Neuroma Presenting as
a Baker Cyst. A Case Report" (81-A: 856-858, June 1999),
by DeLuca and Bartolozzi, which showed an uncommon cause of pain
in the posterior aspect of the knee. Although we applaud the work,
we disagree with the authors’ statement, "To our
knowledge, this case report is the first to document a neuroma-in-continuity
of the tibial nerve as a cause of posterior pain in the knee." We
disagree because we had reported on the same subject in the Spanish-language
literature some five years previously1.
The details of these two rare cases are much the same, but the case
that we reported had showed some special peculiarities.
First of all, the patient was referred to us for excision of
a Baker cyst and, as we did not have a magnetic resonance imaging
scanner in our hospital at that time (1991), we performed a computed
tomographic scan. The scan revealed a 4 x 4-cm mass with radiographic
characteristics that differed from those of a cyst. Then, through
an ultrasonographically guided needle, we obtained a biopsy specimen
that facilitated the right diagnosis. After surgical excision of
the mass through a posterior approach, we discovered a previously
undetected second mass in the same nerve approximately 6 cm distal
to the first one. This finding is considered extremely rare in patients
without von Recklinghausen disease.
The authors’ lack of awareness of this previously published
article should give cause for reflection on the need for consideration
of papers published in non-English-language journals. This oversight
probably occurs because some of these journals are not included
in Index Medicus, a convenient database.
—Peter F. DeLuca, MD
Arthur R. Bartolozzi, MDCorresponding author: Joan C.
Monllau, MD
Department of Orthopaedics
Hospital del Mar
Universitat Autónoma de Barcelona
Passeig Marítim 25-29
08003 Barcelona, Spain
E-mail address: 87024@imas.imim.es
P.F. DeLuca and A.R. Bartolozzi reply:
While we appreciate the commentary by Drs. Oriol, Monllau, Diago,
and Marimón, we feel that it is important to recognize
that in our paper we did qualify that "to our knowledge" this
was the first documentation of neuroma-in-continuity. We unfortunately
failed to uncover the 1994 paper by those authors. There are some
important differences, however. First, in our report, the tibial neuroma
was interpreted by the radiologist as a possible Baker cyst. Second,
an aspiration in the area of the lesion did reveal a small amount
of gelatinous fluid. In retrospect, the magnetic resonance imaging
scan reviewed by the orthopaedic radiologist was not entirely characteristic
of a fluid-filled mass. Oriol and colleagues note that they obtained
the correct diagnosis with use of an ultrasound-guided needle biopsy,
and this certainly assisted in their management of the neuromas.
Nevertheless, the important point is that masses in the posterior
aspect of the knee can certainly have a variety of etiologies. Our
patient had had a previous lumbar laminectomy because of presumed
irritation of the fifth lumbar nerve root; this treatment failed,
of course, because the source of the pain was in the peripheral
nerve at the level of the knee joint. It is clear that masses in
the posterior aspect of the knee can be soft-tissue or fluid-filled
and that, prior to planning surgical exploration or excision, it
is important to make a histological diagnosis. The purpose of our
paper was not to identify a tibial neuroma-in-continuity, but rather
to point out that masses other than Baker cysts can mislead the
operating surgeon and this sometimes can result in inappropriate
surgical treatments (such as the unnecessary lumbar laminectomy
performed on our patient).
We greatly appreciate Drs. Oriol, Monllau, Diago, and Marimón
bringing their case to our attention. We apologize for not recognizing
their work, and we appreciate the opportunity to bring this important
message to print once again.
—Peter F. DeLuca, MD
Arthur R. Bartolozzi, MDCorresponding author: Peter F.
DeLuca, MD
Booth, Bartolozzi, Balderston
Orthopaedics
800 Spruce Street
Philadelphia, PA 19107