Abstract
Category:
Ankle Arthritis; Ankle
Introduction/Purpose:
Previous studies have documented improvement in patient-reported outcomes (PROs) following primary total ankle arthroplasty (TAA) with mean two-year postoperative Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) scores reported as >80 (Norvell et al. JBJS 2019). As TAAs become more common, complications including chronic prosthetic joint infections (PJIs) will be encountered more frequently. Although well-documented in the hip and knee arthroplasty literature, no studies have reported on PROs following a two-stage revision procedure for a chronic PJI after a TAA. The primary purpose of this study was to investigate clinical outcomes at a minimum of two-years postoperatively following a two-stage revision TAA for a chronic PJI. Secondary outcomes were to identify the need for soft-tissue coverage and postoperative complications following the revision.
Methods:
Patients who underwent a two-stage revision TAA for a chronic PJI (>4 weeks after a primary TAA) between January 2010 and December 2019 were eligible to be included in this study. Chronic PJI was defined as a sinus tract that directly communicated with the prosthesis or the same organism identified in 2 synovial fluid samples. Patients were excluded if they did not have at least two-year postoperative Foot and Ankle Ability Measure (FAAM) scores, which are validated patient-reported outcome tools. Twelve patients were eligible to be included in this study. One patient died prior to two-year follow-up, which left 11 patients available for analysis. All eleven patients underwent reimplantation with a stemmed tibial implant and flat-cut talus. Patients were contacted to determine if they had any additional reoperations since their last office note. The data was found not to be normally distributed; therefore, medians and interquartile ranges (IQRs) are reported.
Results:
The median time from primary TAA to resection was 17 months (IQR 2-24 months). Seven of 10 patients required a free flap for soft-tissue coverage prior to reimplantation. At a median of 3.0 years (IQR 2.0-4.0 years) following the second stage of their revision arthroplasty, the median FAAM ADL, Sports, Current Function, and Current Sports Level scores were 60.7 (IQR 52.4, 79.8), 31.3 (IQR 9.4, 40.6), 70 (IQR 25.0, 90.0), and 10 (IQR 0.0, 75.0) (Figure 1). Patients rated their current level of function as 'Severely Abnormal' in 3 patients, 'Abnormal' in 4 patients, 'Nearly Normal' in 3 patients, and 'Normal' in 1 patient. Six patients required a reoperation including three patients who underwent a subsequent irrigation and debridement, one patient who had a below knee amputation, one patient who required a dorsiflexion first metatarsal osteotomy, and one patient who had a subtalar and talonavicular arthrodesis.
Conclusion:
Our study suggests that a two-stage revision TAA is a viable option for patients with a chronic PJI with 90.9% of patients retaining their metal components at a minimum two-year follow-up. However, patients who undergo a two-stage revision TAA for a chronic PJI have lower than previously published two-year FAAM scores and a high rate of flap coverage and reoperation. Only 36.4% of patients rated their function as 'Normal' or 'Near Normal.' This data may be used to help counsel patients about the expected outcome following a two-stage revision TAA for a chronic PJI.
