Comparison of Intermediate to Long-Term Outcomes of Total Ankle Arthroplasty in Ankles with Preoperative Varus, Valgus and Neutral Alignment

SLR - May 2019 - Lindsey Hjelm

Reference: Gun-Woo Lee, MD, Shao-Hua Wang, MD and Keun- Bae Lee, MD, PhD. Comparison of Intermediate to Long-Term Outcomes of Total Ankle Arthroplasty in Ankles with Preoperative Varus, Valgus and Neutral Alignment. J Bone Joint Surg Am. 2018. May 16; 100(10), 835–842.  

Scientific Literature Review

Reviewed By: Lindsey Hjelm, DPM
Residency Program: CHI Franciscan Foot and Ankle Institute, Federal Way, WA

Podiatric Relevance: Total ankle arthroplasty is a treatment modality frequently cited in literature regarding increased functional outcomes, implant longevity and guidelines for successful use. New technology and surgical approaches have reconsidered relative contraindications, such as ankle angular deformity. Literature cites increased risk of implant failure in patients with coronal plane ankle deformities exceeding 15 degrees of varus or valgus. This publication compares the intermediate to long-term outcomes in patients with either neutral, valgus or varus angulation of 5–20 degrees.

Methods: This Level 3 therapeutic study took place in Gwangju, South Korea at the Department of Orthopedic Surgery. A total of 144 patients were divided into three groups consisting of neutral, varus or valgus preoperative tibiotalar coronal deformities. Neutral ankles (51) were categorized by having less than 5 degrees of deformity, while varus (59) and valgus (34) groups had 5–20 degrees of angulation at the ankle. Deformity values were obtained from measuring the bisection of the tibia and talus; however, they did not take into account the congruity of the ankle joint. All patients received a single-stage surgery with HINTEGRA mobile bearing implant as well as soft-tissue and osseous procedures to correct coronal deformities. There was a minimum of four-year follow-up. Postoperative data measurements included tibiotalar radiographic outcomes, clinical scoring systems as well as necessary revisions, complications and longevity of the implant.

Results: All groups had postoperative improvement in clinical assessment scores and range of motion, which were not statistically significant from one another. Varus and valgus groups reported outcomes that were comparable to that of neutral ankles. Radiographic measures demonstrated less deformity correction in the varus group at final follow-up. Overall, there were a greater number of major complications in the preoperative valgus group; however, there was no significant intergroup difference. This study suggests that preoperative coronal deformities should not preclude total ankle arthroplasty. After addressing coronal deformities concomitantly, there is not a statistically different outcome in total ankle arthroplasty as long as a neutral ankle is achieved.

Conclusions: Total ankle arthroplasty in preoperative varus, valgus and neutral ankles had similarly good outcomes after a mean follow-up of 7.3 years. Previous research has demonstrated increased risk for failure in coronal plane deformities exceeding 15 degrees. Limitations include radiographic measurements that did not consider congruency of the joint. This study indicates total ankle arthroplasty should not be excluded in ankles with coronal plane deformities reaching 20 degrees. The use of concomitant soft tissue and osseous procedures in a single-stage surgery can create a neutral ankle with good intermediate to long-term outcomes.