Abstract
CATEGORY: Ankle Arthritis; Ankle INTRODUCTION/PURPOSE: Periprosthetic joint injection (PJI) remains an uncommon but devastating complication after total ankle arthroplasty (TAA). Treatment modalities for PJI in TAA have largely been adapted from hip and knee arthroplasty literature, including the techniques of debridement, antibiotics, and implant retention (DAIR) with polyethylene exchange for acute PJI versus 2-stage revision arthroplasty for chronic PJI. However, the literature investigating treatment of PJI in TAA is limited or historic. Moreover, prior studies indicate poor patient-reported outcomes and high rates of complications and reoperations after TAA PJI, demonstrating the need for continued investigation of treatment guidelines specific to TAA. This study sought to contribute to the very scarce literature available by describing clinical and pathological outcomes for treatment of PJI in TAA at a minimum 2-years follow-up. METHODS: This is a single-institution series of TAA patients (2015-2021) who underwent reoperation or revision for PJI with minimum 2-year follow-up. Guided by Musculoskeletal Infection Society criteria, PJI was defined as: 1) a sinus tract communicating with the TAA, 2) growth of the same organism on 2+ cultures, 3) gross purulence in the joint at the time of surgery, or 4) acute inflammation on histopathologic examination. Debridement and implant retention (DAIR) was defined as retention of metal implants and polyethylene exchange; 2-stage revision was defined as removal of the tibial and talar implants with placement of an antibiotic cement spacer, followed by later return for revision arthroplasty after antibiotic treatment. Treatment was based on the surgeon’s discretion, guided by acute versus chronic PJI diagnosis. The primary outcome was ambulating with TAA implant in-place at final follow-up after PJI. Fisher’s exact test compared categorical variables between PJI patients and non-PJI patients. RESULTS: Thirteen of 973 primary TAA performed between 2015-2021 (1.3%) underwent revision/reoperation for PJI (30.8% female, mean weight 96.5 ± 22.8 kg, mean age 62.1 ± 9.7 years). 5/13 PJI patients (38.5%) had hindfoot arthrodesis prior to primary TAA versus 69 non-PJI patients (7.2%) (P=0.002). At mean follow-up of 3.0 ± 1.9 years, 11/13 patients (84.6%) had undergone successful limb salvage. 7 of those 11 patients were ambulating with TAA in-place; the remaining patients underwent conversion to fusion or permanent cement spacer. Patients were initially treated with DAIR (n=7, 53.8%), 2-stage revision (n=3, 23.1%), or permanent cement spacer (n=3, 23.1%). 3/7 patients (42.9%) treated with DAIR required reoperations/revisions for recurrence; 1/3 patients (33.3%) treated with 2-stage revision required conversion to tibiocalcaneal fusion for recurrence (Table). CONCLUSION: Both DAIR and 2-stage TAA revision appear to be viable options for PJI treatment. However, rates of reoperation remain high and there is significant risk for permanent loss-of-function due to the limited secondary treatment options after failed revision, which include a permanent cement spacer, ankle/hindfoot arthrodesis, and amputation. Additionally, previous hindfoot arthrodesis may be a risk factor for PJI in TAA. Further research is needed to guide evidence-based decision making with regards to treatment strategies for PJI and to improve TAA revision options for PJI that effectively eradicate infection while facilitating the improved ambulation permitted with TAA implant in-place.