Abstract
Submission Type:
Total Ankle Arthroplasty
Research Type:
Level 4 – Case series
Introduction/Purpose:
Distraction arthroplasty aims to treat ankle osteoarthritis while preserving the native ankle joint, with the goal to prevent or delay ankle arthrodesis or total ankle replacement (TAR) for younger patients. Yet when these distraction patients do go on to TAR, there are anecdotal reports of increased stiffness and higher levels of dissatisfaction. However, no study to date has explored TAR outcomes in patients who have had prior distraction arthroplasty. Thus, this study described the clinical, radiographic, and patient-reported outcomes (PROs) for TAR in patients who had undergone prior ankle distraction arthroplasty. We hypothesized that TAR patients with prior distraction arthroplasty would have high rates of radiographic complications, reoperations and revisions, and a low achievement of patient-acceptable symptom state (PASS) thresholds at 2-years follow-up.
Methods:
A retrospective review of prospectively collected data within an institutional TAR patient registry was performed. All patients with a history of ipsilateral ankle distraction arthroplasty who underwent primary TAR between January 2011 and March 2022 were identified. Nineteen ankles in 17 patients met inclusion criteria and were included in the study analysis. Clinical, radiographic, and patient-reported outcomes were collected. The primary aims were to evaluate complication rate and patient satisfaction following TAR. Revisions, reoperations, and radiographic complications within our cohort were compared to literature values to determine potential effects of prior distraction arthroplasty on TAR. Patient-reported outcomes were evaluated using PROMIS before and after undergoing TAR. Statistically significant differences in PROMIS scores at 2-year follow-up were detected using non-parametric Mann-Whitney U tests. Finally, the proportion of patients achieving PASS thresholds at final follow-up was used to assess patient satisfaction following TAR.
Results:
At mean 4.4-year follow-up, 18/19 (94.7%) ankles remained implanted. One TAR was revised due to talus failure. There were four reoperations (1 FHL contracture release, 1 posteromedial ankle arthrotomy for arthrofibrosis, 1 irrigation and debridement for infection, and 1 revision talonavicular fusion); notably, 4 of these 5 ankles had a history of talus ORIF. Radiographic complications, including lucencies, subsidence, and periprosthetic cysts, were observed in 37% at 2 years postoperatively. Patients experienced clinical and statistical improvement in PROMIS domains for Physical Function (P=0.002), Pain Interference (P=0.007), and Pain Intensity (P=0.010). At final follow-up, PASS was achieved by 65% and 71% of patients in the Physical Function and Pain Interference PROMIS domains respectively, but only 35% of patients achieved PASS in the Pain Intensity domain (Table).
Conclusion:
TAR is a viable option to treat ankle osteoarthritis symptoms that persist after distraction arthroplasty, with patient-reported outcomes demonstrating statistically significant improvement following TAR. However, PROs demonstrate relatively lower rates of satisfaction following surgery, which may necessitate increased patient education and expectation management. Furthermore, many of these patients present with posttraumatic etiology and a complex surgical history prior to distraction and therefore may already be at greater risk for reoperation for stiffness-related complications. Ultimately, while TAR and distraction are both useful procedures, using distraction arthroplasty to delay TAR may only further complicate an already-challenging patient cohort and exacerbate subpar outcomes.
