Prospective controlled trial of STAR total ankle replacement versus ankle fusion: initial results.
BACKGROUND
Mobile-bearing ankle replacements have become popular outside of the United States over the past two decades. The goal of the present study was to perform a prospective evaluation of the safety and efficacy of a mobile-bearing prosthesis to treat end stage ankle arthritis. We report the results of three separate cohorts of patients: a group of Scandanavian Total Ankle Replacement (STAR) patients and a control group of ankle fusion patients (the Pivotal Study Groups) and another group of STAR total ankle patients (Continued Access Group) whose surgery was performed following the completion of enrollment in the Pivotal Study.


METHODS
The Pivotal Study design was a non-inferiority study using ankle fusion as the control. A non-randomized multi-centered design with concurrent fusion controls was used. We report the initial perioperative findings up to 24 months following surgery. For an individual patient to be considered an overall success, all of the following criteria needed to be met: a) a 40-point improvement in total Buechel-Pappas ankle score, b) no device failures, revisions, or removals, c) radiographic success, and d) no major complications. In the Pivotal Study (9/00 to 12/01), 158 ankle replacement and 66 arthrodesis procedures were performed; in the Continued Access Study (4/02 to 10/06), 448 ankle replacements were performed, of which 416 were at minimum 24 months post-surgery at time of the database closure.


RESULTS
Major complications and need for secondary surgical intervention were more common in the Pivotal Study arthroplasty group than the Pivotal Study ankle fusion group. In the Continued Access Group, secondary procedures performed on these arthroplasty patients decreased by half when compared with the Pivotal Arthroplasty Group. When the Pivotal Groups were compared, treatment efficacy was higher for the ankle replacement group due to improvement in functional scores. Pain relief was equivalent between fusion and replacement patients. The hypothesis of non-inferiority of ankle replacement was met for overall patient success.


CONCLUSIONS
By 24 months, ankles treated with STAR ankle replacement (in both the Pivotal and Continued Access Groups) had better function and equivalent pain relief as ankles treated with fusion.
Saltzman
Charles L
CL
Mann
Roger A
RA
Ahrens
Jeanette E
JE
Amendola
Annunziato
A
Anderson
Robert B
RB
Berlet
Gregory C
GC
Brodsky
James W
JW
Chou
Loretta B
LB
Clanton
Thomas O
TO
Deland
Jonathan T
JT
Deorio
James K
JK
Horton
Greg A
GA
Lee
Thomas H
TH
Mann
Jeffrey A
JA
Nunley
James A
JA
Thordarson
David B
DB
Walling
Arthur K
AK
Wapner
Keith L
KL
Coughlin
Michael J
MJ
D000328:Adult; D000368:Aged; D000843:Ankle Joint; D001168:Arthritis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D019643:Arthroplasty, Replacement; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007595:Joint Prosthesis; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011859:Radiography; D020127:Recovery of Function / Q000502:physiology; D016896:Treatment Outcome; D016474:Weight-Bearing / Q000502:physiology