Abstract
Category:
Ankle, Ankle Arthritis
Introduction/Purpose:
While ankle arthrodesis (AA) has long been considered the gold standard treatment for ankle arthritis, total ankle arthroplasty (TAA) has become increasingly popular with improving implant designs. Although AA is currently performed more frequently than TAA, it has been associated with increased pain/degeneration, and loss of function in adjacent joints of the foot. Contrastingly, TAA has been suggested to preserve motion of the ankle while reducing the stress imposed on other areas of the foot. However, it has been questioned whether TAA may carry a higher risk for hardware failure and infection. The purpose of this study was to assess complications associated with these two surgical methods, and compare patient characteristics for better risk stratification when choosing to perform one procedure over the other.
Methods:
Query was performed using the Pearl Diver Patient Records Database (Pearl Diver Inc., Colorado Springs, CO), which contains all Medicare patient records from 2008-2014. All patients who underwent an arthroscopic/open AA (CPT-27870; 29899) or TAA (CPT: 27870, 29899) were identified. Perioperative complications within the 30-day period following operation were identified and categorized as major complications (mortality, surgical site infections, myocardial infarctions, pulmonary embolisms, deep venous thromboembolisms, cerebral vascular accidents, sepsis, peri-prosthetic fracture, and peripheral nerve injury), minor complications, and 30-day readmission rate. Upon matching patients for age, gender, and body mass index, t-tests were used to analyze differences in continuous variables, while chi-squared analyses were utilized for categorical variables. An adjusted multivariate logistic regression model was generated to assess for independent associations between the two procedures and postoperative outcomes. Results were considered significant at p<0.05.
Results:
7,077 patients were identified, of which 1,765 (24.9%) underwent TAA and 5,312 (75.1%) underwent arthroscopic/open AA. The AA cohort demonstrated significantly higher rates of preoperative comorbidities, including congestive heart failure (p=0.004), smoking (p=0.029), rheumatoid arthritis (p<0.001), renal disease (p<0.001), and diabetes (p<0.001), than the TAA group. The TAA cohort, however, demonstrated a greater 30-day readmission (p<0.001) than the AA cohort. After controlling for significant differences in preoperative characteristics, TAA was still found to be associated with a significantly higher risk for 30-day readmission when compared to AA (OR 2.69, 95% CI 2.12-3.41, p<0.001). Significant independent risk factors for major complications included smoking history (OR 2.17, 95% CI 1.51-3.11, p<0.001), renal disease (OR 2.25, 95% CI 1.45-3.41, p<0.001), and diabetes (OR 1.84, 95% CI 1.28-2.67, p=0.001).
Conclusion:
Although the AA cohort demonstrated higher rates of preoperative comorbidities, TAA was independently found to be associated with a higher risk for readmission within 30 days than AA. Although TAA does appear to be associated with increased rate of readmission, there was no significant difference in major or minor complications between AA and TAA. With this in mind, TAA remains a reasonable treatment option for appropriately selected patients suffering from ankle arthritis. Surgeons should also take into account the patients’ health, as multiple specific comorbidities among both procedures were independently associated with higher risks for major and minor complications.
