Copyright © 2007 by The Journal of Bone and Joint Surgery, Inc.
Commentary & Perspective
Commentary & Perspective by
Christopher P. Chiodo, MD*,
Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
Posted October 2007
Ankle arthrodesis is effective, reliable, and technically
straightforward. It affords substantial pain relief and restoration of function
in patients with arthritis of the ankle. In one recent clinical series of forty-eight
patients undergoing ankle arthrodesis, the fusion rate was 96% with significant
improvement in the average AOFAS (American Orthopaedic Foot and Ankle Society)
ankle-hindfoot score (p < 0.0005)1.
Nevertheless, the decreased sagittal-plane motion that
results from ankle arthrodesis adversely impacts function. Moreover, this
procedure is associated with the development of degenerative change in the
ipsilateral hindfoot. In one long-term review, moderate or severe ipsilateral
subtalar arthritis developed in 91% of patients who underwent ankle arthrodesis2.
As a result of these long-term consequences, many orthopaedic surgeons now
consider total ankle replacement to be a viable alternative to arthrodesis and
are more frequently offering this operation to their patients3. This
trend is likely to continue as advances are made in implant design and as new
prostheses are developed. Further, the indications for total ankle replacement
are expanding beyond only ideal candidates with good bone stock and minimal
deformity.
In the present study, SooHoo and colleagues used the
California inpatient discharge database to review more than 5000 patients who
underwent total ankle replacement and ankle arthrodesis from 1995 through 2004.
Long and short-term outcomes, including the rates of infection, revision
surgery, and subtalar joint fusion, were analyzed. Logistic and proportional hazard
regression models were also used.
The authors confirmed the longstanding notion that patients who
have had total ankle replacement are more likely to need major revision surgery
than are patients who have had ankle arthrodesis (23% compared with 11%, respectively,
at five years postoperatively). With total ankle replacement, there was also a
higher risk of readmission for an infection that was related to the implanted
device. Meanwhile, in patients who underwent ankle arthrodesis, there was an
increased risk of the development of ipsilateral subtalar arthritis (2.8% in
patients who had ankle arthrodesis compared with 0.7% in patients who had ankle
replacement).
For orthopaedists who treat ankle arthritis, these findings
represent straightforward and useful data that should prove helpful when
counseling patients who are considering ankle replacement and/or arthrodesis. The
important yet abstract concept of "risk tolerance" becomes pertinent and can be
more readily factored into the clinical decision-making process.
Of course, the current study is not without limitations. As
the authors acknowledge, patients who undergo ankle arthroplasty may not be comparable
with patients who undergo arthrodesis. Indeed, patients who underwent
arthrodesis in this study were more likely to have uncontrolled diabetes and
osteonecrosis. Furthermore, some may consider subtalar arthritis to be a
contraindication to ankle replacement, thereby falsely decreasing the rate of
subtalar arthritis in patients who undergo total ankle replacement.
Nevertheless, SooHoo and colleagues are to be commended for
conducting a well-structured population-based investigation and presenting concise
and useful data that should be shared with all patients who are considering
total ankle replacement and ankle arthrodesis.
*The author did not receive any outside funding or grants in
support of his research for or preparation of this work. Neither he nor a
member of his immediate family received payments or other benefits or a
commitment or agreement to provide such benefits from a commercial entity. No
commercial entity paid or directed, or agreed to pay or direct, any benefits to
any research fund, foundation, division, center, clinical practice, or other
charitable or nonprofit organization with which the author, or a member of his
immediate family, is affiliated or associated.
References
1. Colman AB, Pomeroy GC. Transfibular ankle arthrodesis with rigid internal fixation: an assessment of outcome. Foot Ankle Int. 2007;28:303-7.
2. Coester LM, Saltzman CL, Leupold J, Pontarelli W. Long-term results following ankle arthrodesis for post-traumatic arthritis. J Bone Joint Surg Am. 2001;83:219-28.
3. Easley ME, Vertullo CJ, Urban WC, Nunley JA. Total ankle arthroplasty. J Am Acad Orthop Surg. 2002;10:157-67.
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