Background: The efficacy of total ankle replacement compared with
that of ankle fusion continues to be one of the most debated topics in foot
and ankle surgery. The purpose of this study was to determine whether there
are sufficient objective cumulative data in the literature to compare the two
procedures. A systematic review of the literature addressing the intermediate
and long-term outcomes of interest in total ankle arthroplasty and ankle
arthrodesis was performed.
Methods: A comprehensive search of MEDLINE for all relevant articles
published in English from January 1, 1990, to March 2005 was conducted.
Additionally, relevant abstracts from the 2003 and 2004 annual proceedings of
major orthopaedic meetings were eligible. Two reviewers evaluated each study
to determine whether it was eligible for inclusion and collected the data of
interest. Meta-analytic pooling of group results across studies was performed
for the two procedures. The analysis of the outcomes focused on
second-generation ankle implants.
Results: The systematic review identified forty-nine primary
studies, ten of which evaluated total ankle arthroplasty in a total of 852
patients and thirty-nine of which evaluated ankle arthrodesis in a total of
1262 patients. The mean AOFAS (American Orthopaedic Foot and Ankle Society)
Ankle-Hindfoot Scale score was 78.2 points (95% confidence interval, 71.9 to
84.5) for the patients treated with total ankle arthroplasty and 75.6 points
(95% confidence interval, 71.6 to 79.6) for those treated with arthrodesis.
Meta-analytic mean results showed 38% of the patients treated with total ankle
arthroplasty had an excellent result, 30.5% had a good result, 5.5% had a fair
result, and 24% had a poor result. In the arthrodesis group, the corresponding
values were 31%, 37%, 13%, and 13%. The five-year implant survival rate was
78% (95% confidence interval, 69.0% to 87.6%) and the ten-year survival rate
was 77% (95% confidence interval, 63.3% to 90.8%). The revision rate following
total ankle arthroplasty was 7% (95% confidence interval, 3.5% to 10.9%) with
the primary reason for the revisions being loosening and/or subsidence (28%).
The revision rate following ankle arthrodesis was 9% (95% confidence interval,
5.5% to 11.6%), with the main reason for the revisions being nonunion (65%).
One percent of the patients who had undergone total ankle arthroplasty
required a below-the-knee amputation compared with 5% in the ankle arthrodesis
Conclusions: On the basis of these findings, the intermediate
outcome of total ankle arthroplasty appears to be similar to that of ankle
arthrodesis; however, data were sparse. Comparative studies are needed to
strengthen this conclusion.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.