To The Editor:
In the article entitled "Fluoroscopically Guided Low-Volume
Peritendinous Corticosteroid Injection for Achilles Tendinopathy. A Safety
Study" (2004;86:802-6), by
Gill et al., the authors concluded that it is safe to inject corticosteroids
under direct fluoroscopic visualization into the peritendinous space for the
treatment of Achilles tendinopathy. Figure 1 of the article demonstrates a
potential peritendinous space between the paratenon and the Achilles tendon
into which the authors tried to inject steroid with use of tenography.
However, from the available literature, we know that the paratenon can be
affected in the early phase of tendinopathy and that adhesions can be formed
between the tendon and the paratenon1, obliterating this potential
space. Obviously, in such cases, the technique described by the authors will
deliver steroid into pre-Achilles fat rather than into the peritendinous
space.
The concern raised by Dr. Hulse and colleagues is that an injection of
fluid anterior to the Achilles tendon may in fact be instilled in the anterior
fat pad. He may be correct, but the question remains unresolved. The article
that they cite1 is a
review article that mentions adhesions of the peritenon to the tendon, and
there is no citation that corroborates that statement.
There has been extensive surgical experience demonstrating changes in the
peritenon and adhesion of the membrane to the tendon, but the location of the
adhesive condition has not uniformly been in the region anterior to the
tendon. One large
series2 indicated
that the peritenon was found to be thickened in 40% of patients at the time of
surgery and that it was not always adherent to the tendon. Dr. Maffulli is
very experienced in Achilles tendon surgery and perhaps has some unpublished
data that he would like to share concerning the prevalence and location of
peritendinous adhesions.
On the basis of the two-dimensional imaging that we utilized (planar
fluoroscopy), we cannot conclusively state whether the injection technique
described in our article delivers contrast medium, anesthetic, and
corticosteroid into the fat pad.
This raises the intriguing possibility that the technique of passing the
needle from posterior to anterior through the Achilles tendon may, in some
cases, lead to injection directly into the fat pad and not the peritendinous
space. The image labeled as Figure 2 in our article demonstrates a layering of
the contrast medium along the anterior edge of the tendon, suggesting that at
least some of the fluid is located along the anterior surface of the tendon.
To determine whether this was true during some or all of the procedures, we
will have to visually examine each of the pictures that were made during the
procedure. The premise of Achilles tendon safety with corticosteroid injection
remains intact because of the documentation that the drug is not injected into
the tendon.
What needs to be determined is the actual location of the fluid that is
injected anterior to the tendon, and this, perhaps, may be discovered in a
future study to determine efficacy. We thank Dr. Hulse and colleagues for
bringing this possibility to our attention.
Maffulli N, Kader D. Tendinopathy
of tendo achillis. J Bone Joint Surg Br.2002;84:
1-8.841
2002
[PubMed][CrossRef]
Astrom M, Rausing A. Chronic
Achilles tendinopathy. A survey of surgical and histopathologic findings.
Clin Orthop.1995;316:
151-64.316151
1995
[PubMed]