Reoperation rates are higher for ankle arthroplasty than fusion, mostly related to implant design (AAOS)
TITLE: Comparing Reoperation after Ankle Joint Fusion or Replacement: Experience within a Prospective Multicenter Study
AUTHORS:
Alastair S E. Younger, MD, Vancouver, British Columbia, Canada
Timothy R. Daniels, MD, FRCSC, Toronto, Ontario, Canada
Mark Glazebrook, MD, Halifax, Nova Scotia, Canada
Murray J. Penner, MD, Vancouver, British Columbia, Canada
Kevin J. Wing, MD, Vancouver, British Columbia, Canada
Peter Dryden, MD, Victoria, British Columbia, Canada
INTRODUCTION: Repeat surgery is a measure of failure of the primary surgery if the surgery is performed at the original site. Repeat surgery may be avoided in the future if the cause is recognized and procedures or devices modified accordingly. The repeat surgery results in cost to the system as a result of additional clinic visits, additional days in hospital, and extra hours of surgery plus the cost of additional devices and biologics. Payers may refuse a primary procedure that may be of benefit to patients because of the potential cost of repeat surgery. Ankle replacement may be refused in favor of fusion for some payers based on this argument.
Currently no paper exists as to the reoperation rate on the primary site for ankle joint replacement and fusion. Terminology on review of prior papers is variable and in some outcome papers reoperation rates are not reported. This paper outlines the reoperation rate for ankle joint replacement and fusion from a multicenter database, and describes a classification system for reoperation for use in end stage ankle arthritis.
METHODS: A total of 214 ankle fusions (AF) and 474 total ankle arthroplasty (TAA) were prospectively followed from four centers and six surgeons from 2003 to 2010. Repeat operations were recorded. These were classified (table 1). If a period of stable function existed for at least two years, a second reoperation code was used. For a series of reoperations (such as for two stage revision for infection), a single code was used. The reoperation codes were stratified in severity and when more than one code existed, the more severe code was used. Chi squared analysis was used to assess differences.
RESULTS: Of the total group (688 pts), no reoperation was performed in 75% (516/688), 86% for AF (183/214) and 70% for TAA (331/474) with fewer reoperations being performed for ankle fusion (p<0.0001). The reoperation rate around the ankle joint was 10% (22/214) for AF and 6% for TAA (28/474) (p>0.05). Reoperation rates within the ankle joint were 5% (10/214) for AF and 24% (115/474) for TAA (p<0.0001). The rate of amputation was 2% (3/214) for AF and 1% (4/214) for TAA (p>0.05). The rate of isolated hardware removal was 4% (24/688) for the all procedures, 9% (19/214) for AF, and 1% (6/474) for TAA (p<0.005). There were two operations around the ankle for AF including surrounding joint fusions (1%) and 22 for TAA (22/474) (p>0.05). For total ankles there were 6% of joints debrided for HO or gutter impingement (27), 3% rate of isolated polyethylene exchange for failure (12 in 10 joints – two repeat procedures), 3% rate of grafting of bone cysts with retention of components (13), 11% rate of revision of metal components for malposition or loosening (51 procedures in 49 primary joints), 2% rate of revision for infection (10 two-stage revisions in seven primary procedures). The wound reoperation rate was 2% (7/688) for the whole group, being 1% for AF (2/214) and 2% for TAA (11/474)(p>0.05).
SUMMARY: Reoperation rates are higher for total ankle replacement and most seem to relate to design issues. Fusion around ankle fusions remains low. The coding system developed may provide a better framework for assessing reoperations than prior complication classification systems such as modifications of the Claviden Dindo system. This paper indicates the need for improvement of ankle joint replacement design and technique if the full potential of the operation is to be realized. 