Post-Operative Lucency Formation Amongst Stemmed vs Non-Stemmed Total Ankle Arthroplasty Constructs

Abstract

Category: Ankle Arthritis; Ankle; Hindfoot Introduction/Purpose: Current available total ankle replacement constructs offer either proximal projecting pegs (non- stemmed) in various shapes or large stem (stemmed) designs to the superior aspect of the tibia component. Each design offers inherent stability and unique function. Periprosthetic radiolucency can develop post-operatively and lead to adverse effects. However, the incidence and clinical significance of lucency formation amongst stemmed and non-stemmed constructs is poorly understood. Methods: A retrospective radiographic and chart analysis was performed of 256 patients, under a single orthopedic practice, who underwent primary TAA between 2013-2019 with one of 3 total ankle systems. Pre-operative ankle characteristics, intraoperative procedures, as well as post-operative angles, lucency formation, region of lucency formation, and patient outcomes were analyzed. Results: Patients' mean age 65.5 yrs., male n=126 and female n=127, a mean follow-up of 24.3 months for our patient cohort. A total of 149 stemmed and 107 non-stemmed constructs were analyzed. Incidence of periprosthetic tibial lucency formation 33.2%, stemmed implants 10.0%, and 65.4% for non-stemmed implant (p value 0.00001). Conclusion: This paper describes the incidence of periprosthetic formation amongst a stemmed and non-stemmed total ankle arthroplasty cohort. Statistical significance was found when analyzing stemmed vs. non-stemmed incidence of radiolucency formation, this did not correlate with increased incidence of post-operative complications.