Assessing The Role of Primary Ankle Arthrodesis In An Arthroplasty World
Total ankle arthroplasty has become more prevalent through the years and has changed our outlook and approach to end-stage ankle arthritis. Advances in technology as well as as surgeon skill sets made outcomes more reproducible and aided in salvaging progression of periarticular deformities.
One of the more commonly debated issues surrounding total ankle arthroplasty is survivorship of the implants. Morash and colleagues looked at survival rate in the current literature and concluded that it was approximately 75 to 90 percent at 10 years with total joint arthroplasty.1
The benefits of total ankle arthroplasty are obvious: preserving motion at the ankle joint, which, in turn, also preserves the surrounding joints. I also find my practice following the trend to preserve motion at the ankle joint when possible and notice my total ankle arthroplasty numbers increasing while ankle arthrodesis are decreasing.
However, I do believe it is important not to lose sight of the importance of ankle arthrodesis in foot and ankle surgery. Accordingly, let us take a closer look at some pertinent considerations when contemplating whether or not ankle arthrodesis is right for your patient.
Surgeon skill set. In 2017, Usuelli and colleagues sought to identify the learning curve for total ankle arthroplasty.2 Looking specifically at mobile-bearing devices, the authors found that “most of the operative variables as well as clinical and radiological outcomes stabilize after a surgeon has performed 28 cases.”2 Simonson and team performed a systematic review of complications during the surgeon learning curve period for primary total ankle replacement.3 After reviewing 2,453 primary total ankle replacements they identified a 44.2 percent complication rate.
Age. Although some recent research explores the use of total ankle arthroplasty in younger patients, proceed with caution in this patient population.4,5 Often younger patients have higher functional demands that may lead to a greater number of surgeries and revisions within the implant’s life span. Physiologic age may also be correlated with patient expectations and activity level. These qualitative measures are paramount when discussing the life span of the proposed surgical intervention.
Coronal plane deformity. Preoperative coronal plane deformity of greater than 20 degrees is considered a contraindication for total ankle arthroplasty.6 Surgeons should strongly consider ankle arthrodesis for patients who have significant varus or valgus deformity. Surgeon skill set is also important within this patient demographic.
Avascular necrosis. One should avoid joint arthroplasty in patients with tibial or talar avascular necrosis. A thorough workup is important when there is suspicion of avascular necrosis. Consider obtaining both computed tomography (CT) and magnetic resonance imaging (MRI) for these patients prior to determining surgical intervention. There are advanced options for talar avascular necrosis including total talar replacement but that is beyond the scope of this blog.
In Conclusion
When it comes to deciding between ankle arthroplasty and arthrodesis, surgeons should do so on a case-by-case basis while taking key patient-specific risk factors into consideration. Primary ankle arthrodesis should be a consideration in (but not limited to) younger, more active patients, those with greater than 20 degrees of coronal plane deformity, and patients with avascular necrosis.
Dr. Pirozzi is a Fellow of the American College of Foot and Ankle Surgeons (ACFAS) and serves as Vice President for ACFAS Region 2. She is currently in private practice in Phoenix, Ariz.
References
1. Morash J, Walton DM, Glazebrook M. Ankle arthrodesis versus total ankle arthroplasty. Foot Ankle Clin. 2017;22(2):251-266.
2. Usuelli FG, Maccario C, Pantalone A, Serra N, Tan EW. Identifying the learning curve for total ankle replacement using a mobile bearing prosthesis. Foot Ankle Surg. 2017;23(2):76-83.
3. Simonson DC, Roukis TS. Incidence of complications during the surgeon learning curve period for primary total ankle replacement: a systematic review. Clin Podiatr Med Surg. 2015;32(4):473-482.
4. Lee GW, Seon JK, Kim NS, Lee KB. Comparison of intermediate-term outcomes of total ankle arthroplasty in patients younger and older than 55 years. Foot Ankle Int. 2019;40(7):762-768.
5. Demetracopoulos CA, Adams SB Jr, Queen RM, DeOrio JK, Nunley JA 2nd, Easley ME. Effect of age on outcomes in total ankle arthroplasty. Foot Ankle Int. 2015;36(8):871-880.
6. Lee GW, Lee KB. Outcomes of total ankle arthroplasty in ankles with >20 of coronal plane deformity. J Bone Joint Surg Am. 2019;101(24):2203-2211.
