The Agility Total Ankle Arthroplasty

SLR - June 2009 - Park, Naasz, Riley

Reference:
Knecht, S., Estin, .M., Callaghan, J.J., Zimmerman, M. (2004). The Agility Total Ankle Arthroplasty. The Journal of Bone and Joint Surgery (American), 86, 1161-1171.

Scientific Literature Review

 

Reviewed by:  Joseph K Park, DPM; Eric B Naasz, DPM; Brendan Riley, DPM
Residency Program:  DVA Greater Los Angeles Healthcare System/Olive View-UCLA Medical Center


Podiatric Relevance:
This article provides long-term results of the possible benefits of total ankle arthroplasty. Total ankle implants have been notoriously associated with failure since their inception. The Agility prosthesis by Depuy has now been utilized enough that long-term follow-up has shown favorable results providing an alternative to ankle joint
arthrodesis.

Methods:
This is a retrospective study of all Agility total ankle replacements performed at the University of Iowa Department of Orthopaedics from 1984-1994. The primary preoperative diagnosis was posttraumatic arthritis (46%), but also included primary osteoarthritis (29%), rheumatoid arthritis (23%), and post infectious arthritis (2%). The patient average age at the time of surgery was 61 years (range 27-83 years), and the average weight was 85.5 kg (range 47-123kg). Follow up evaluation consisted of both (1) subjective evaluation with the use of The Ankle Osteoarthritis Scale and a short questionnaire to determine pain and disability satisfaction, and (2) post-operative radiographic evaluation including component subsidence, arc of component motion, angular migration, time until syndesmosis fusion, the presence of healing or healed fractures, peri-implant bone loss or lysis, and the presence of hindfoot arthritis.

Results:
One hundred and thirty-two Agility total ankle replacements were performed in 126 patients. Fourteen ankle replacements (11%) required major revision consisting of complete revisional replacement or ankle joint arthrodesis secondary to infection, fracture, or component loosening or impaction. Secondary procedures were defined as any procedure in the foot or ankle related to the ankle replacement but not directly involving the ankle replacement components. These secondary procedures included most commonly syndemosis screw removal, but also included three triple arthrodeses, three subtalar arthrodesis, and two calcaneal osteotomies. In total, 46 of the 132 ankle replacements required some type of revision. However, more than 90% of the patients reported decreased pain and satisfaction with the outcome. Ninety-four percent stated that they would have the surgery again, and 97% would recommend the surgery to a friend.

Conclusions:
On basis of these findings, the Depuy Agility total ankle arthroplasty was shown to produce a high percentage of patient satisfaction and function. However, it may require revisional procedures in order to combat component positioning and impaction. The Agility total ankle arthroplasty is a viable alternative to ankle joint arthrodesis.