Takedown of Painful Ankle Arthrodesis to Total Ankle Arthroplasty: A Case Series of 77 Patients

Takedown of Ankle Arthrodesis and Conversion to Total Ankle Arthroplasty: A Systematic Review

Management of the nonunited or painful ankle arthrodesis remains a difficult challenge. The aim of this systematic review was to investigate the clinical outcomes and complications of conversion of an ankle fusion to a total ankle replacement (TAR). The PRISMA statement guidelines were followed. A literature search was performed in PubMed, Science Direct and Cochrane Central Register of Controlled Trails (CENTRAL) from their inception up to October 10th, 2023. The quality of the included studies was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal tool and the Methodological Index for NonRandomized Studies (MINORS). Seven studies with 220 patients (223 ankles) with a mean follow-up of 64.9 months were included. Takedown of an ankle fusion and conversion to a TAR led to a significant improvement in all functional and clinical scores and with an acceptable range of motion. Most common complications were malleolar fractures (12.8%) and arthrofibrosis (5.6%). The revision rate was 8% and 4 cases resulted in a below-knee amputation. Cases with an insufficient fibula had a good outcome when a fibular reconstruction was performed. In conclusion, takedown of an ankle fusion and conversion to a TAR has satisfactory clinical outcomes and with a limited number of complications. Future well-designed studies are needed to validate the results of the present study.

Total Ankle Arthroplasty in Young Patients

With continuing advancements in total ankle arthroplasty (TAA), it is quickly becoming the procedure of choice for older patients with end-stage ankle arthritis. Multiple studies have been conducted on younger patients who have undergone TAA with promising results, but is it the procedure of choice? Considerations of TAA versus ankle arthrodesis, TAA implant longevity, outcomes of revision TAA, and whether patients should be offered an arthrodesis with plans for conversion to arthroplasty may help elucidate whether pursuing ankle arthroplasty in a younger, more active population is the correct approach for surgeons.

Outcomes of Conversion of Ankle Fusion to Total Ankle Arthroplasty

With ankle replacements gaining popularity and documented good functional outcomes, there is an increasing number of patients inquiring about the possibility of converting an ankle fusion to a replacement. This could be due to pain, limited function, or increasing adjacent joint arthritis. There is an increasing body of evidence in the literature that a conversion to a replacement is possible and that the outcomes are positive. There are also absolute contradictions for a conversion. An absent fibula, pain of unknown origin, and recent infection fall in this category. Long-term follow-up is needed to see if conversions of ankle fusions to replacements have the same functional results and longevity as primary replacements.

Takedown of Ankle Fusions and Conversion to Total Ankle Replacements

BACKGROUND

With ankle replacements gaining credibility, there is a small subset of patients who might benefit from a conversion of an ankle fusion to a replacement. The objective of this study is to present clinical and radiographic results of patients who had their ankle fusion converted to total ankle arthroplasty (TAA).

METHODS

Patients presented to the senior author with ongoing ankle pain following fusion or increasing pain after a period of relative comfort after an ankle fusion. Outcomes were evaluated preoperatively and postoperatively with the Veterans Rand Health Survey (VR-12), Ankle Osteoarthritis Scale (AOS), and visual analog scale (VAS) pain scale. A patient satisfaction survey was also distributed.

RESULTS

All ankle fusion conversions between April 2010 and December 2019 were included. Fifty-one patients (30 females) with the mean age of 62.6 (range, 37-83) years were followed. Mean follow-up was 4.2±2.3 (range, 2-11.5) years. Two patients were lost to follow-up (1 is deceased). Pre- and postoperative mean patient-reported outcome scores were all significantly different between groups except VR-12 mental subscale scores. VR-12 physical scores improved from 28.7±8.9 preoperatively to 38.9±9.9 (P < .001) postoperatively; VR-12 mental score was stable. AOS pain and disability subscales similarly improved: 55.9±24.4 to 27.9±25.4 (P < .001) and 61.7±21.1 to 31.1±25.7 (P < .001), respectively. VAS pain improved from a mean of 64.5±27.3 to 29.4±27.7 (P < .001). There was no tibiotalar dorsiflexion or plantarflexion with the ankle fusion. Initial postoperative visit revealed that average dorsiflexion was 10.9±5.93 degrees and average plantarflexion was 14.1±5.22 degrees. At the latest follow-up, dorsiflexion improved significantly to 15.5±6.33 degrees (P < .001), with no significant improvement in plantarflexion (P = .980).

CONCLUSION

In this single-surgeon longitudinal study of 51 patients with a painful, malaligned, or nonhealed ankle fusion treated with an ankle replacement, we found highly satisfactory functional outcomes at an average of 4.2 years. Continued long-term follow-up will reveal whether the longevity of these replacements is comparable to primary replacements.

Total Talar Replacement With Custom-Made Vitallium Prosthesis for Talar Avascular Necrosis

Background: The current study investigated the application of three-dimensional (3D) printing technology in the treatment of talar avascular necrosis (TAN). Custom-made Vitallium talar prostheses were designed and generated via 3D printing. We hypothesized that these talar prostheses would facilitate more stable positioning, better ergonomically fit the ankle joint surfaces, and promote favorable long-term prognoses. Material and Methods: Computed tomography scans of both ankle joints were acquired from three patients diagnosed with TAN. The talar on the unaffected side was used as the design blueprint. Hence, with the aid of 3D printing technology a customized talar prosthesis made from a novel Vitallium alloy could be manufactured for each individual patient. Results: In all three cases there were no signs of prosthesis loosening or substantial degenerative change in the surrounding area of the joint, but small osteophytes were observed on the tibial side and navicular side. No chronic infection or other prosthesis-related complications were observed in any of the patients. All three were able to walk without pain at the most recent follow-up. Conclusion: With the aid of 3D printing and a novel Vitallium alloy, total talar replacement achieved encouraging results in 3/3 patients. All patients were satisfied with their joint function, and were able to return to their daily activities without limitations. Although more cases and longer-term follow-up periods are required, the success rate reported herein is encouraging.

Outcomes of Ankle Arthrodesis Conversion to Total Ankle Arthroplasty: A Systematic Review

Ankle arthrodesis (AA) provides reliable pain relief, good patient satisfaction scores, and improved overall function. However, this procedure has been associated with numerous complications and sequelae, such as pseudoarthrosis, malunion, gait abnormalities, increased demand on surrounding joints, and a long period of convalescence. Conversion to total ankle arthroplasty (TAA) is a potential option in the management of these complex and challenging situations. The purpose of this study is to investigate the outcomes of AA conversion to TAA. A systematic review of electronic databases was performed. Six studies involving 172 ankles met inclusion criteria. The weighted mean preoperative Visual Analogue Scale (VAS) score at the time of TAA conversion was 7.8 and the weighted mean postoperative VAS score at the time of final follow-up was 2.5. The weighted mean preoperative AOFAS score at the time of TAA conversion was 32 and the weighted mean postoperative AOFAS score at the time of final follow-up was 72.4. The rate of salvage tibiotalocalcaneal arthrodesis was 2.3% and rate of transtibial amputation was also 2.3% after attempted conversion from initial AA to TAA. Conversion of AA to TAA appears to be a viable option to improve patient outcomes and prevent extensive hindfoot arthrodesis and transtibial amputation. More prospective studies with consistent reporting of outcomes, complications, and revision rates with long-term follow-up are needed.