Early Complications of Primary Total Ankle Replacement with Talar Bone Loss

Submission Type: Ankle Arthritis Research Type: Level 4 – Case series Introduction/Purpose: Predictors of complications following total ankle arthroplasty (TAA) become more important as the incidence and indications for TAA continue to expand. Talar bone loss whether from avascular necrosis, osteoarthritis, or post traumatic arthritis can be a challenging problem to deal with in TAA. The aim of this study is to report predictors of complications in TAA with talar bone loss. Methods: A retrospective review using CPT codes for four surgeons over a three-year period at an academic institution was performed. A single surgeon reviewed the immediate preoperative plain radiographs for 200 consecutive patients for talar bone loss. The mortise and lateral views were used, and an example measurement is shown in Figure 1. 37 patients were identified as having talar bone defects of greater than 20 percent when the two measurements were averaged. Our preoperative variables we evaluated were size of talar defect, location, and cause of talar defect and postoperatively, the implant choice. Our primary outcomes were intraoperative fracture, reoperation, subsidence, and revision surgery. Results: The average follow up was 27 months. The average defect size was 54 percent with a range of 20 to 100 percent. Mann U Whitney tests were performed that showed a relationship between the lateral percentage and the overall percentage leading to subsidence of the talar component. A Fischer exact test showed a relationship between subsidence and revision components versus primary only components. The mean of the talar bone loss for the revision components was 58% versus 40% in primary components. There were no other significant differences when comparing complications, fracture, reoperation, or wound complications. Conclusion: While TAA for patients with talar bone loss can be a good option for both the patient and surgeon it has a higher complication rate in our series than previously described. Careful attention should be given to the percentage of talar bone loss especially on the lateral. Revision style components are likely used in worse situations, so it is not the authors belief that they are more prone to subsidence. However, all patients over 20% bone loss need extensive discussion regarding potential complications and additional procedures.