Clinical and Radiographic Outcomes at a Mean of 7 Years Following Primary Transfibular Total Ankle Arthroplasty in Younger and Older Patients
Kevin A. Schafer, Jonathan Day, Morgan Motsay, Helen Zhang, Zijun Zhang, Lew C. SchonBackground:
Total ankle arthroplasty (TAA), traditionally performed through an anterior approach, has generally been reserved for older patients. A lateral transfibular approach requires minimal osseous resection and permits implantation into denser bone, which may make it a durable option for younger candidates. This study compared midterm implant survivorship and clinical and radiographic outcomes following primary transfibular TAA in patients younger and older than 55 years.
Methods:
Patients who underwent primary transfibular TAA and had a minimum follow-up of 5 years were included. Patient-reported outcome measures (PROMs) included the 12-Item Short-Form Health Survey (SF-12), Ankle Osteoarthritis Scale (AOS), and visual analog scale (VAS) for pain. Radiographic alignment, range of motion, and periprosthetic cysts (radiolucency of >2 mm) were assessed. Adverse events and reoperations were reported. Outcomes in younger (<55 years old) and older (≥55 years old) patients were compared using multivariable linear regression and linear mixed models.
Results:
Two hundred and fifty-one ankles (in 236 patients; 86% White) were included. The younger group included 72 ankles (in 70 patients, mean age of 45.4 years [95% confidence interval (CI), 43.7 to 47.1] years) with a mean of 6.9 (6.2 to 7.5) years of follow-up; the older group included 179 ankles (in 166 patients, mean age of 65.7 years [64.7 to 66.7] years) with a mean of 7.0 (6.7 to 7.3) years of follow-up. The younger group more commonly had a primary diagnosis of posttraumatic arthritis (83% versus 61%) and a history of ankle fracture fixation (84% versus 68%) (both p < 0.05). There were no significant differences between the younger and older groups in the rate of adverse events (40.3% versus 33.0%), time to reoperation (21.7 versus 27.4 months), implant revision (1.4% versus 0%), or periprosthetic cysts (5.6% versus 2.8%). In analyses controlling for confounding variables, age did not demonstrate significant associations with pre- or postoperative PROMs, alignment, or range of motion (all p > 0.05).
Conclusions:
Although this study was not designed to determine equivalence between the age groups, favorable midterm outcomes were observed in both younger and older patients. These results suggest that transfibular TAA may be a viable treatment option for end-stage ankle arthritis across a wide age range, but longer-term follow-up is needed.
Level of Evidence:
Therapeutic