Meta-analysis finds comparable intermediate outcomes between total ankle replacement and ankle fusion

Total ankle replacement was associated with a 7% revision rate, primarily due to loosening or subsidence.

A systematic review of intermediate and long-term outcomes for total ankle replacement found excellent or good results in 82% of cases who received a second-generation ankle device compared to 72% of cases treated with ankle fusion.

In addition, total ankle replacement resulted in a lower revision rate than fusion, according to the study.

Steven L. Haddad, MD, and colleagues searched Medline for all relevant articles comparing outcomes between total ankle replacement and ankle fusion published between 1990 and 2005. They also reviewed relevant abstracts from major orthopedic meetings for 2003 and 2004. The researchers focused outcomes for second-generation ankle implants.

The systematic review identified 49 primary studies; 10 studies evaluated total ankle replacement in 852 patients and 39 studies evaluated ankle fusion in 1,262 patients, according to the meta-analysis, published in the Journal of Bone and Joint Surgery.

Overall, 52% of the second-generation total ankle replacement patients had excellent results, 30% had good results, 4% had fair results and 13% had poor results. In the fusion group, 35% had excellent results, 37% had good results, 14% had fair results and 14% had poor results.

The American Orthopaedic Foot and Ankle Society (AOFAS) Ankle Hindfoot Score in the meta-analysis for total ankle replacement averaged 78.2 points and averaged 75.6 points for fusion.

The 5-year implant survivorship rate was 78% and 10-year implant survivorship rate was 77%. The revision rate for total ankle replacement was 7% and was primarily due to loosening and/or subsidence. Ankle fusion was associated with a 9% revision rate, primarily due to nonunion.

"The implications of this study reach far and wide," said Haddad in a press release from DePuy Orthopaedics, a Johnson & Johnson Company.

DePuy manufacturers the Agility Total Ankle Replacement System, which is one of the devices reviewed in the meta-analysis.

"Surgeons, insurers, and of course patients need solid clinical evidence to weigh the advantages of total ankle replacement against ankle fusion, which permanently reduces a patient's ankle movement," he said in the release.

However, adoption of the procedure has been limited by the lack of reimbursement for the procedure as insurers wait for clinical evidence to accumulate.

"Some health insurance programs still don't cover ankle replacement because insurers have pointed to the need for more clinical evidence to substantiate positive intermediate and long-term outcomes for the technology," said Haddad. "This study may help to answer that need."

For more information:
Haddad SL, Coetzee JC, Estok R, et al. Intermediate and long-term outcomes of total ankle arthroplasty and ankle arthrodesis. A systemic review of the literature. J Bone Joint Surg Am. 2007;89-A:1899-1905.