Patients considering surgery for end-stage ankle arthritis often ask which treatment—arthroplasty or arthrodesis—will help the most. Findings from various studies attempting to answer that complex question have been equivocal. In the July 3, 2019 issue of The Journal of Bone & Joint Surgery, Shofer et al. inject some objective data gleaned from step counters worn by 234 patients into this predominantly subjective question.
All patients were treated with either arthroplasty (n = 145) or arthrodesis (n = 89). Their step activity was measured with a StepWatch 3 Activity Monitor preoperatively and at 6, 12, 24, and 36 months postoperatively. In both groups combined, step counts during “high activity” (>40 steps per minute) increased by 46% over 36 months. At 6 months, the mean high-activity step improvement was 194 steps in the arthroplasty group, compared with a mean decline of 44 steps for the arthrodesis group. However, by 36 months after surgery, the between-group differences in high-activity steps had disappeared.
The authors also analyzed associations between the objective step results and 3 patient-reported outcomes (the Musculoskeletal Function Assessment and the SF-36 physical function and pain scores). Unlike the patient-reported scores, which improved dramatically in the first 6 months and then plateaued, improvements in step activity increased gradually throughout the 3-year follow-up.
The authors emphasized that during the first 12 postoperative months, the arthrodesis patients had little or no improvement in step activity, but at 3 years there were no significant differences between arthrodesis and arthroplasty patients. These findings suggest that, in this clinical scenario, an individual patient’s expectations with the pace of improvement may be a suitable topic during shared decision making conversations.
This study does not entirely reconcile previously equivocal findings regarding arthroplasty-versus-arthrodesis, but it does emphasize the substantial and sustained activity benefits that patients in both groups receive. Shofer et al. conclude that objective measurements from wearable technology “may complement patient-reported outcomes” in future longitudinal outcome studies of many orthopaedic treatments.
Among the many variables discussed when patients and surgeons make a decision between ankle arthrodesis (fusion) and total ankle replacement (TAA) for end-stage ankle arthritis, in-hospital complication rate is an often-overlooked point of comparison, partly due to a dearth of good data.
In the September 6, 2017 edition of The Journal of Bone & Joint Surgery, Odum et al. report findings from a matched cohort study that compared these two ankle procedures in terms of minor and major perioperative complications. To make more of an apples-to-apples comparison, the authors statistically matched 1,574 patients who underwent a TAA with an equal number of those who underwent fusion.
A major in-hospital complication (such as a pulmonary embolism or mechanical hardware problem) occurred in 8.5% of fusion patients and in 5.3% of TAA patients. After adjusting for case mix, Odum et al. found that ankle arthrodesis was 1.8 times more likely than TAA to be followed by a major complication. Regarding minor in-hospital complications (such as venous thrombosis or hematoma/seroma), the authors found a 29% lower risk of complications among arthrodesis patients compared to TAA patients, although that difference was not statistically significant (p = 0.14). Regardless of surgical procedure, patient age ≤67 years and the presence of multiple comorbidities were independently associated with a higher risk of a major complication.
A possible explanation for the lower in-hospital major-complication rate in TAA patients, say the authors, is that “TAA is more likely to be performed in younger, healthier patients with better bone quality and smaller deformities.”