Failed Total Ankle Replacement Research Articles

Revision Total Ankle Arthroplasty Using a Novel Modular Fixed-Bearing Revision Ankle System.

Large bone defects such as those encountered after failed total ankle replacement have previously been a relative contraindication to revision ankle replacement due to inadequate bone stock. We describe our experience and patient reported outcomes with a modular ankle replacement system with tibial and talar augments. This is a retrospective case series analysis of patients who underwent a total ankle replacement using the INVISION system across 2 centers between 2016 and 2022. Patients completed the Manchester-Oxford Foot Questionnaire (MOXFQ), Ankle Osteoarthritis Scale (AOS), and EQ-5D pre-operatively and then post-operatively at 6 months, 1 year, 2 years, 3 years, and 5 years. Medical records were reviewed for complications and re-operations. X-rays were reviewed for lucencies and alignment. A total of 17 patients were included in the study; 14 men and 3 women with an average age at the time of surgery of 67.9 years (range 56-80 years). The average follow-up post-operatively was 40.5 months (range 7-78) at the time of this study. The indication for surgery was revision of failed total ankle replacement (TAR) in 16 and revision of failed ankle fusion in 1. An augmented tibia was used in 13, an augmented talus in 13, and both augmented tibia and talus in 9 cases. There were no early surgical complications. One patient required debridement and implant retention for late deep infection. No implants have been revised. The average MOXFQ score improved by 19.3 points at most recent follow-up. The average AOS score improved by 25.2 points. The early results of a modular augmented ankle arthroplasty system have shown satisfactory patient outcomes with a low complication and re-operation rate and present another option for patients with larger bone defects. This is a small series, and a larger series with long-term follow-up would be beneficial. Level IV: Case series.

Lessons from Revision Total Ankle Replacement: Tibias Fail Early, and Taluses Fail Late (And Fail Again)

Introduction/Purpose: With the last decade’s surge in total ankle replacement (TAR), there is an anticipated commensurate increase in the number of revisions that orthopaedic foot and ankle surgeons will encounter. The salvage and implant options to deal with a failed primary TAR are expanding. However, the literature on survivorship and outcomes after revision TAR in the modern era is relatively limited. What’s more, little is known about the risk factors for further revision or failure of revision TAR. This study aimed to describe the timing to and survivorship after revision TAR. We hypothesized that tibial-sided failures would occur earlier after the index surgery, and secondary revisions after failure of revision TAR would occur more due to talar-sided failures than tibial-sided failures. Methods: This is a single-institution retrospective cohort study of TAR patients (2012-2022) with minimum 2-year follow-up. Revision TARs (defined as exchange of tibial and/or talar components) with any implant (Cadence, Inbone, Invision, Infinity, Salto, STAR, Vantage, Zimmer; or custom total talus replacement [TTR]) were included. Five surgeons contributed patients. Demographics, primary and revision surgical data, and postoperative complications were recorded. Etiology of failure necessitating revision (tibial failure, talus failure, combined failure) and ultimate outcomes after revision (revision TAR survived, additional revisions, conversion to fusion, below-knee-amputation [BKA]) were recorded. Revisions for periprosthetic joint infection (PJI) and conversions to fusion were excluded. There were 59 ankles that underwent revision for any cause. Excluding 9 2-stage revisions for PJI and 3 conversions to ankle or tibiotalocalcaneal fusion, there were 47 ankles that underwent revision TAR that were included for analysis. Chi-square and ANOVA tests were used to compare risk factors and timing for failure. Results: There were 47 revision TARs, with mean age 60.6 (range: 31-77) years, mean BMI 29.5 kg/m2, 19 (40.4%) females, and mean 3.5 years follow-up. Revisions for tibial failure (n=22) occurred significantly earlier (1.3 ± 0.5 years) than those for talus failure (n=19, 2.3 ± 1.7 years) or combined tibial/talus failure (n=6, 2.9 ± 3.3 years) (P=0.048). Revisions for tibial-only failure had significantly better survivorship (95.5%) than revisions for talus or combined tibia/talus failures: 26% of talus failures and 33% of combined tibia/talus failures underwent at least one more revision (P=0.033). Of the 7 failures after revision talus, 2 ultimately underwent BKA, 2 were converted to TTR, 2 were revised to modular stemmed talus implants, and 1 was treated with explant and cement spacer for PJI. Conclusion: This study demonstrates that TAR tibial failures occur earlier than talus failures or combined tibial/talus failures. When patients with isolated tibial failure undergo revision of both tibial and talar components, they usually do well with good survivorship post-revision. However, revisions for talar failures and combined tibial/talar failures occur later but are more devastating: nearly 1/3 go on to a second revision. This is important given the consequences of talar implant subsidence, bone necrosis, loss of bone stock, and limited salvage options. As TAR utilization expands, it is imperative to develop implants and surgical strategies to maximize success for revision surgery. Flowchart of failures after revision TAR. PJI = periprosthetic joint infection. TTC = tibiotalocalcaneal. BKA = below-knee amputation. Tibial implant geometry included: Low-pro = lowprofile tibial implant. Stem = stemmed tibial implant. Keel = keeled tibial implant. Talus implant geometry included: chamfer/round and flat-cuttalus.

Early results of combined total ankle total talus replacement in the revision setting

BackgroundRevision of failed total ankle replacement (TAR) is challenging and associated with increased morbidity. Given the increased popularity of TAR in treating end-stage ankle arthritis (ESAA), viable revision options are needed. The objective of this case series is to present a minimum 2-year clinical and radiographic outcomes of patient-specific custom 3D-printed total ankle total talus (TATR) prostheses in this unique subset of patients. Methods19 participants with ESAA and failed primary TAR who underwent TATR by a single surgeon at our institution from 2019 to 2021 were retrospectively identified. All participants were indicated for revision of primary STAR implant (Stryker, Kalamazoo, MI) and underwent replacement with 3D-printed titanium implants based on preoperative CT analysis (Additive Orthopaedics, Little Silver, NJ). Custom components included a mobile-bearing total talus and stemmed tibial system, performed through an anterior approach. Pre- and postoperative patient-reported outcomes were assessed using the Patient Reported Outcomes Measurement Information System (PROMIS). Pre- and postoperative implant alignment was assessed using medial distal tibial angle (MDTA) and tibiotalar angle (TTA) on anteroposterior, and sagittal tibial angle (STA) on lateral weight-bearing plain films. ResultsThe average patient age was 60.6 (range, 39–77) years, with an average follow-up of 37.9 (range, 25.3–57.5) months. There was statistically significant improvement in all PROMIS domains. Short-term survivorship was 100%, with two participants (11.0%) requiring reoperation for postoperative complications: one underwent open reduction internal fixation of the tibia for a periprosthetic fracture, and another underwent medial gutter debridement and tarsal tunnel release for recurrent pain. There were no significant differences in pre- versus postoperative radiographic alignment measured by MDTA (89.9 vs 86.4), TTA (89.7 vs 88.1), or STA (85.2 vs 85.3). ConclusionCustom 3D-printed TATR is a promising option for revision TAR. There was significant short-term improvement in pain and physical function, with excellent short-term survivorship and an acceptable postoperative complication rate.

Successful Limb Salvage Reconstruction Using Bulk Femoral Head Allograft

Category: Ankle Introduction/Purpose: The use of femoral head allografts in salvage surgeries for lower extremity reconstruction help address surgical problems of large bone deficits. There are very few publications and mixed results in the literature as to the outcomes of this salvage procedure. These limb salvage procedures involve significant surgical complexity with the end goal of retaining a stable, brace-able lower extremity. The purpose of this retrospective review is to report the results and utility of bulk femoral head allograft for limb salvage including time to weight bearing, CT confirmed fusion time, reoperation rates, and ultimate limb salvage success. Additionally, this article categorizes femoral head surgical preparation, adjunct biologics use, fixation constructs, and dissection techniques used. Methods: Patients who underwent reconstructive limb salvage surgery using femoral head allografts over a 5-year period (2015- 2020) were identified. The surgeries were among 5 different fellowship-trained surgeons at a single institution. Indications included post-traumatic AVN, Charcot ankle, revisional surgery, and failed total ankle replacement. Femoral heads were used in either ankle fusions alone or in tibiotalocalcaneal fusion. Time to weight bearing, CT fusion time, reoperations, and ultimate limb salvage were recorded. Reoperations were reported minor if involved partial HWR, superficial I&Ds, or exostosis/HO removal. Major reoperations were defined as full revision surgery/failure of femoral head construct, placement of antibiotic rods for deep infection, or BKA. Limb salvage was defined as being successful if the patient was walking with or without bracing at the last follow-up. Results: Twenty-three cases were identified with 13 performed for failed total ankle replacements, 7 post-traumatic avascular necrosis of the talus, and 3 neuropathic Charcot ankles. The average radiographic follow-up time was 665 days with an average time to weight bearing of 86.48 days. 18/23 patients had CT confirmation of femoral graft union with an average time to union of 461.92 days. 9 patients were found to have less than 50% graft incorporation at the last follow-up. There were 9 reoperations recorded, 8 minor and 1 major. All patients were chart documented stable with independent weight bearing either with or without a brace on the last clinic follow-up. Conclusion: Limb salvage in cases of large bone defects can be very challenging. We report a high success rate of limb salvage using bulk femoral head allograft. Complete fusion of bulk femoral head allograft although desirable, was not necessary to maintain limb salvage in this retrospective study. Patients were able to weight bear and maintain the integrity of the bulk allograft despite the lengthy time to achieve fusion in cases where fusion was achieved. This study highlights that bulk femoral head allograft can offer excellent salvage options with a high degree of success in complex limb salvage reconstruction.

Isolation and characterisation of wear debris surrounding failed total ankle replacements.

Aseptic loosening and osteolysis continue to be a short- to mid-term problem for total ankle replacement (TAR) devices. The production of wear particles may contribute to poor performance, but their characteristics are not well understood. This study aimed to determine the chemical composition, size and morphology of wear particles surrounding failed TARs. A recently developed wear particle isolation method capable of isolating both high- and low-density materials was applied to 20 retrieved periprosthetic tissue samples from 15 failed TARs of three different brands. Isolated particles were imaged using ultra-high-resolution imaging and characterised manually to determine their chemical composition, size, and morphology. Six different materials were identified, which included: UHMWPE, calcium phosphate (CaP), cobalt chromium alloy (CoCr), commercially pure titanium, titanium alloy and stainless steel. Eighteen of the 20 samples contained three or more different wear particle material types. In addition to sub-micron UHMWPE particles, which were present in all samples, elongated micron-sized shards of CaP and flakes of CoCr were commonly isolated from tissues surrounding AES TARs. The mixed particles identified in this study demonstrate the existence of a complex periprosthetic environment surrounding TAR devices. The presence of such particles suggests that early failure of devices may be due in part to the multifaceted biological cascade that ensues after particle release. This study could be used to support the validation of clinically-relevant wear simulator testing, pre-clinical assessment of fixation wear and biological response studies to improve the performance of next generation ankle replacement devices. STATEMENT OF SIGNIFICANCE: Total ankle replacement devices do not perform as well as total hip and knee replacements, which is in part due to the relatively poor scientific understanding of how they fail. The excessive production of certain types of wear debris is known to contribute to joint replacement failure. This is the first study to successfully isolate and characterise high- and low-density wear particles from tissues collected from patients with a failed total ankle replacement. This article includes the chemical composition and characteristics of the wear debris generated by ankle devices, all of which may affect their performance. This research provides clinically relevant reference values and images to support the development of pre-clinical testing for future total ankle replacement designs.

Long-Term Survival of Hintegra Revision Ankle Arthroplasty in 116 Patients

Category: Ankle; Ankle Arthritis; Hindfoot Introduction/Purpose: Total ankle replacement (TAR) became a popularly utilized surgical solution for end-stage ankle osteoarthritis (OA). Consequent to the increased number of primary implantations, failed ankles are evermore challenge for foot and ankle surgeons. Historically, if the ankle failed, salvage was preferably fusion. Nowadays however, maintenance of the ankle and hindfoot functionality is first and foremost for the expanded patient group. Despite revision arthroplasty has been described as a viable option, the available literature on long-term outcomes is scarce. The aim of this study was to investigate the long-term survival of revision ankle arthroplasty in a uniquely large cohort using the mobile-bearing HINTEGRA prosthesis. Methods: We conducted a single-center retrospective cohort study included 116 patients (117) ankles following revision ankle arthroplasty for failed primary TAR from July 2000 to March 2010. Survival analysis was performed. Clinical outcomes including pain on visual analog scale (VAS), American Foot and Ankle Ankle-Hindfoot Score (AOFAS), ankle range of motion (ROM), and patient`s satisfaction were assessed preoperatively and at the last follow-up. Results: The mean follow-up time from initial revision arthroplasty to the latest follow-up was 15.0+-3.0 years (range 11.2 - 20.5). The cumulative survival of the revised ankles at 5, 10 and 15 years was 81+-4%, 74+-4%, and 70+-4%, respectively. Clinical outcomes including pain on VAS declined from median 6 (0 - 10) to 2 (0 - 10) (p<.0001)), and the AOFAS ankle-hindfoot score improved from 43+-17 to 70+-20 (p<.0001)) from preoperatively to the last follow-up. Conclusion: Despite difficult surgical challenge, revision ankle arthroplasty yields an acceptable survival rate and results on long- term, however lower than primary TAR. Careful preoperative planning is crucial to achieve the desired results. Fusion is may not anymore the state-of-the-art solution for failed ankles. The study provides unique information for foot and ankle surgeons improving patient-care and possibly influence decision-making process.

Short-Term Outcomes of a Two-Component Total Ankle Replacement in Revision Arthroplasty

Category: Ankle Arthritis; Ankle; Hindfoot Introduction/Purpose: Given the growing number of primary total ankle replacements (TAR), an increase in the numbers of failed ankles and consecutive revisions might be expected. Achieving a stable and balanced ankle based on stable components while preserving the remaining bone stock as much as possible, are crucial for success in revision TAR. Most reported techniques rely on bulky implants with extended fixation features. Since 2018, we have used a novel 3-component ankle for revision surgery that is converted in situ to a fixed-bearing 2-component ankle once the components have found their position given by the individual anatomy. The purpose of this study was to determine the short-term results of this novel concept in revision TAR. Methods: This single-center retrospective cohort study included 57 patients (57 ankles, mean age 63+-13 years) treated for failed TAR with the semi-constrained HINTERMANN Series H2© (H2) implant between February 2018 and February 2020. Survival analysis was performed and potential risk factors using Cox regression, were assessed. Clinical and radiological outcomes were assessed preoperatively and at the last follow-up. Clinical outcomes included pain on a visual analog scale (VAS), the American Orthopaedic Foot & Ankle Society (AOFAS) ankle hindfoot score and patient satisfaction. Radiological outcomes were tibial articular surface angle (TAS), tibiotalar surface angle (TTS), talar tilt angle (TT) in the coronal plane and anteroposterior offset (AP-Offset) ratio in the sagittal plane, as well as signs of radiolucency and/or loosening on plane weightbearing radiographs. Results: The median follow-up was 2 (2.0 to 4.0) years. The cumulative incidence for secondary revision after 1 and 2 years was 5.1% (95%CI 0-11) and 7.4% (0-14) respectively. Four patients needed a secondary revision (three for pain/arthrofibrosis and one for aseptic loosening). While the AOFAS hindfoot score increased from median 54 (range 9-94) to 75 (19-98) (p=0.00001), satisfaction increased from moderate to good (p=0.0017). Radiographically, all components were stable without signs of increased shear-forces in terms of loosening or radiolucency. Conclusion: Obtained results with the novel customized semi-constrained total ankle implant design at short-term are encouraging, with a satisfactory survival rate and acceptable revision rate. The fixation concept without extended fixation features was shown to last against increased shear forces.

Revision Total Ankle Replacement using the Inbone 2 System, Nottingham Experience

Category:Ankle Arthritis; AnkleIntroduction/Purpose:The Inbone Total Ankle Replacement System (Wright) is a modular stemmed ankle replacement, it is marketed as for both primary and revision TAR, it has been in use at Nottingham since 2016 mainly for revisions, we are reporting our experience with this system and our early results.Methods:This is a retrospective study with prospective collected data. We identified 27 (18M/9F) patients who had Inbone 2 TAR for revision surgery during the period August 2016 -March 2019. The mean follow up was 21 months (7-38months). Mean age of 69 years (51-81).All ankle revisions were a single-stage revision apart from 1 patient who had a 2 stage revision as at the first stage infection was suspected, it was left with a cement spacer and when all samples came back negative the second stage was carried out.All patients had follow up appointments at 6 weeks, 3,6 and 12 months. Patients were required to fill in MOXFQ questioner and all had weight-bearing radiographs on every follow up appointment.The indication for the surgery was aseptic Loosening 23, Malalignment 1 Insert wear 2 and heterotopic ossification 1.Results:20 patients had concurrent procedure during the surgery(Table 1). There was 1 deep wound infection that required DAIR procedure 3 weeks after the revision surgery and has gone to make full recovery, no other complication were reported.Improvement in clinical outcome and PROMS data was noted on follow up, MOXFQ for Pain improved from 70 pre op to 34 at 6 months and 32 at 1 year(p<0.001 paired t test),The outcome for Walking improved from 69 pre op to 41 at 6 months and 40 at 1 year(p<0.001 paired t test).Radiological alignment was maintained in all ankles both in the coronal and the sagittal plain, posterior heterotopic ossification was noted in 8(29%), No loosening or signs of failure at any follow up appointmentConclusion:This is one of the largest series of this implant used in revision TAR. Our early results show considerable improvement in patient outcomes with very low complications and no failures.This implant provides a good option as a revision implant and our view that it is a superior solution to ankle fusions for failed total ankle replacements

Outcomes of revision surgery for failed total ankle replacement: revision arthroplasty versus arthrodesis.

To compare the short-term outcomes of surgical management of failed ankle arthroplasty with revision ankle arthroplasty and conversion to arthrodesis. Single-centre retrospective review of revision procedures for failed ankle arthroplasty between January 2012 and June 2019. Implant survival, union rates, and PROMS data-Pain Visual Analogue Score (VAS), Ankle Osteoarthritis Score (AOS) and Manchester-Oxford Foot Questionnaire (MOxFQ)-were compared between the two groups. Twenty-nine patients (31 ankles) underwent surgical management for failed ankle arthroplasty, with either revision arthroplasty (n = 21) or arthrodesis (n = 10). Revision arthroplasty had 87% survival at four years. Arthrodesis had an overall union rate of 80%. Two-year PROMS showed greater results for the revision arthroplasty group compared with that for arthrodesis group (Pain VAS 10 vs 50, p = 0.03; total AOS 12 vs 87, p = 0.04; average MOxFQ 17 vs 73.5, p 0.02). Revision arthroplasty demonstrates good short-term survival data with improvements in PROMS compared with arthrodesis. Further long-term follow-up is required to monitor if these benefits continue.

Comparison of Custom 3D Printed Spherical Implants vs Femoral Head Allografts for Tibiotalocalcaneal Arthrodeses

Category:Ankle Arthritis, HindfootIntroduction/Purpose:Tibiotalocalcaneal (TTC) arthrodesis is a common treatment option for hindfoot arthritis, deformity correction and salvage of failed total ankle replacement. However, union can be difficult to achieve in patients with bulk bone defects. Femoral head allograft is commonly used in the setting of TTC fusion with severe bone loss, but recent studies have reported concerns of arthrodesis rates of 50% or worse and graft collapse in these patients. Retrograde intramedullary nail placement through custom 3D spherical implants is a novel option for these patients. The purpose of this study was to compare fusion rates, graft resorption and complication rates between patients undergoing TTC fusion with 3D sphere implants versus femoral head allografts.Methods:All patients who underwent TTC arthrodesis with an intramedullary nail along with a 3D spherical implant or femoral head allograft by the senior author at a single institution from 2013 to 2017 and who had at least one year of follow-up were included in this study. There were 7 patients who received a femoral head allograft and 8 patients who received a 3D printed sphere. Baseline patient and operative characteristics were collected and compared between the 3D sphere and femoral head allograft groups. The rate of successful fusion of the tibia, calcaneus and talar neck to the 3D sphere or femoral head allograft, as determined by radiographs and CT scan, as well as graft resorption and complications were compared between the groups.Results:The rates of union of the tibia (87.5% vs 71.4%), calcaneus (87.5% vs 71.4%), and talar neck (100% vs 42.9%) were higher in the 3D sphere group than in the femoral head allograft group. The rate of union of the talar neck was significantly higher to the 3D sphere implant than to the femoral head allograft (p=0.016). The number of patients achieving successful fusion of all three articulations was higher in the 3D sphere group (75%) than the femoral head allograft group (42.9%), although not statistically significant (p=0.22). The rate of graft resorption was significantly higher in the femoral head allograft group (57.1%) than the 3D sphere group (0%, p=0.016).There were no differences between the groups in terms of complications.Conclusion:These data demonstrate that the use of a custom 3D-printed sphere implant is safe in patients with severe bone loss undergoing TTC arthrodesis with a retrograde intramedullary nail. The rate of successful fusion of all three tibial, calcaneal and talar neck articulations was higher to the 3D sphere than to the femoral head allograft, although not statistically significant. Union of the talar neck was significantly higher to the 3D sphere implants than it was to the femoral head allograft. Subsidence was significantly higher with the femoral head allograft than the 3D sphere.

Total Ankle Replacement Conversion to Tibiotalocalcaneal Arthrodesis With Bulk Femoral Head Allograft and Pseudoelastic Intramedullary Nail Providing Sustained Joint Compression

Tibiotalocalcaneal (TTC) arthrodesis is commonly performed to salvage a failed total ankle replacement. These salvage procedures are complicated by significant bone loss from the ankle replacement and are associated with low patient satisfaction. Here, we describe 2 cases of patients who presented with a failed total ankle replacement and underwent arthrodesis using a bulk femoral head allograft and a novel pseudoelastic intramedullary nail. The intramedullary nail contains an internal pseudoelastic element that adapts to bone resorption and settling allowing for compression to be maintained at the arthrodesis sites throughout healing. In the first case, a 65-year-old woman with a failed total ankle replacement underwent TTC arthrodesis. The second case involved an obese 53-year-old woman who had previously undergone 2 total ankle replacement procedures that resulted in unsuccessful outcomes. In both cases, union was demonstrated on computed tomographic scan by 6 months. At 2 years postsurgery, both patients were satisfied with the procedure. These cases provide preliminary evidence that tibiotalocalcaneal arthrodesis with a pseudoelastic IM nail and structural allograft is an appropriate treatment for failed total ankle replacements. Level of Evidence: Level IV, therapeutic, case series.

Ankle fusion after failed ankle replacement in rheumatic and non-rheumatic patients

BackgroundWith longer follow-up, survival rate of total ankle replacements (TAR) diminishes. It is therefore important to have a reliable fall-back option in case of failed TAR. Revision arthroplasty is often impossible because of loss of bonestock or infection. Conversion to ankle fusion is then indicated. We investigated the clinical, radiographic and patient reported results for fusion after failed TAR in a consecutive group of patients. We concentrated on the influence of inflammatory joint disease (IJD) on union rate. MethodsPatient files and radiographic images of 46 consecutive patients (47 ankles) were reviewed. There were 22 patients with IJD. Fixation methods included; anterior plating, blade plate fixation, intramedullary nailing, compression screws and external fixation. Foot and Ankle Outcome Score (FAOS) and Foot and Ankle Ability Measure (FAAM) were used to determine patient related outcomes. ResultsForty out of 47 ankles (85%) Fused. Union rate in the non-IJD group (96%) was significantly higher compared to the IJD-group (73%, p=0.04). Revisions and complications were more frequent in the IJD group, but numbers were too small to detect a significant difference. Mean PROM scores were: FAOS-symptoms; 68.5, FAOS-pain; 70.3, FAOS-QoL; 43.7, FAOS-ADL; 68.1 and FAAM-ADL; 52.1, with no significant difference between IJD and non-IJD patients. ConclusionsIJD-patients have a higher nonunion rate after ankle fusion for failed TAR. However, patient reported outcome is not significantly different between the two groups. Level of evidenceIV, retrospective cohort.

Effect of Stem Cell Augmented Micronized Allograft on Arthrodesis in the Ankle and Foot

Category: Basic Sciences/Biologics Introduction/Purpose: Both primary and revision arthrodesis are mainstays of foot and ankle surgery. Many studies have investigated the effect of autograft, varying forms of bone graft substitutes, and of biologic agents on bone healing, including in the setting of arthrodesis. A commercially available stem cell augmented micronized allograft (Via Graft®) is comprised of micronized (100-300 microns) allograft bone with marrow-isolated adult multilineage inducible cells (MIAMI cells). It has been proposed as an alternative to autograft and as an adjunct to arthrodesis. We present a series of 86 patients with minimum one-year follow-up who underwent either primary or revision arthrodesis with Via Graft®, with or without additional graft. Methods: Between 2015 and 2016, 86 patients treated with Via Graft® were identified with minimum one-year follow-up. Data was collected including demographic information, BMI, smoking history, medical comorbidities; indication for fusion (including Charcot arthropathy, posttraumatic arthritis, rheumatoid arthritis, AVN, congenital anomalies, neuromuscular disorders, revision surgery, post-infectious, previous total ankle arthroplasty, posterior tibial tendon dysfunction); procedure performed (ankle, hindfoot, midfoot, or forefoot fusion), number of joints fused, use of additional graft, radiographic union, and complications. Fusion was evaluated based upon radiographic or CT evidence of osseous bridging. The unit of the analysis was the joint. Generalized Linear Mixed Model (GLMM) was utilized to evaluate the association between fusion and the data set described above. Statistical analyses were performed using SAS® 9.4. Results: 191 joints were fused in 86 patients (F: 48, M: 38). Mean age was 58.7 years, mean follow-up was 15.8 months. Radiographic union was achieved in 163/191 (85.3%) joints. Age, gender, smoking status, presence of diabetes, history of Charcot, revision fusion, or use of cancellous autograft or allograft demonstrated no statistically significant differences in fusion rates. Intramedullary talocalcaneal arthrodesis (IMTCA), with or without additional joints fused simultaneously (p=.001), use of structural allograft (most commonly femoral head)(p&lt;.001), structural autograft (p=.001), history of previous TAA (p&lt;.0001), and history of AVN (p=.042) demonstrated statistically significant rates of nonunion, despite use of Via Graft® (Table 1). Conclusion: This study is the largest series to date of Via Graft® augmentation of arthrodesis. Lower union rates were found to be associated with patients undergoing hindfoot fusion with an IMTCA with or without additional joints fused, a history of failed total ankle replacement or AVN of the talus, and use of femoral head allograft. However, this preliminary study requires further analysis given the difficult and salvage nature of these cases. As bony union is multifactorial, the selection of bone graft and biologic agents is an important factor, but may not be sufficient to overcome the biology of the host.

Salvage arthrodesis of a failed total ankle replacement using a custom 3D-printed cage implant: A case report and review of the literature

We present a case report of a 66-year-old female who underwent salvage arthrodesis after a failed Scandinavian Total Ankle Replacement secondary to aseptic loosening and talar subsidence. Secondary to the loss of talar integrity the decision was made to proceed with revisional ankle arthrodesis. To maintain limb length the primary surgeon (EH) elected to use a custom cage implant in combination with an intramedullary nail construct in a single stage approach. The custom cage was augmented with autograft &amp; allograft cancellous bone in addition to allograft recombinant human bone morphogenic protein, and allograft adult mesenchymal stem cells. The incision sites healed post-operatively without incident and at post-op week 16 the patient progressed to full unrestricted weight bearing in normal shoe wear with a gauntlet ankle brace. Although an isolated report, this case shows promise for further development of the technique. We believe this revisional arthrodesis technique warrants further research and consideration as a potential addition to the failed total ankle arthroplasty treatment algorithm.

Poor outcomes of fusion with Trabecular Metal implants after failed total ankle replacement: Early results in 11 patients.

One of the reasons for revision of total ankle replacement (TAR) implants is loosening due to subchondral cysts. Reconstruction and fusion of the ankle is often the first choice for revision procedures due to the large bone defects, which are typically filled with autograft and/or allograft. Filling the defect with a trabecular metal tantalum implant is a potential alternative given the biomechanical properties of this component. Using tantalum as a spacer provides primary stability and contributes to fusion of the ankle joint after removal of failed TAR implants. Eleven patients underwent arthrodesis an average of 6.9 years after TAR. The mean height of the bone defect was 32mm. It was filled with a specially designed quadrangular implant (Trabecular Metal™, Zimmer/Biomet) combined with an iliac crest graft. Ten patients underwent tibio-talo-calcaneal (TTC) arthrodesis fixed with an angled retrograde nail and one patient underwent talocrural arthrodesis fixed with two plates (anterolateral and anteromedial). The clinical, functional (AOFAS and SF36 scores) and radiological (plain X-rays and CT scan) outcomes were determined. At a mean follow-up of 19.3 months, the mean total AOFAS score was 56 (21-78) and the mean SF36 score was 60.5 (19-84). One patient was lost to follow-up and four patients still had pain. The tantalum implant was integrated in six patients. Five patients achieved fusion of the subtalar joint and 8 achieved fusion of the talocrural joint. Three patients required surgical revision. Our hypothesis was not confirmed. The clinical outcomes after more than 1 year of follow-up are disappointing, as was the large number of nonunion cases and the lack of tantalum integration. These technical failures can be explained by insufficient construct stability and/or insufficient implant porosity. IV (retrospective cohort study).

Use of a trabecular metal spacer implant after failed total ankle replacement

Use of a trabecular metal spacer implant after failed total ankle replacement

Failed Agility™ LP Total Ankle Replacement Salvaged with Tibio-Talo- Calcaneal Arthrodesis and Vascularized Pedicled Medial Malleolus and Fibula Onlay Bone Grafts

Controversy exists regarding the most predictable salvage for failed total ankle replacement. Revision total ankle replacement with soft-tissue release/reconstruction or explantation with tibio-talo-calcaneal arthrodesis with bulk structural allograft are the most commonly performed approaches. Tibio-talo-calcaneal arthrodesis with bulk structural allograft has a high complication rate; however, augmentation with vascularized pedicled onlay bone grafts may improve osseous union and functional limb salvage. This manuscript presents the revision of a failed Agility™ LP total ankle replacement system with severe >45° varus ankle deformity that was salvaged with tibio-talocalcaneal arthrodesis, bulk femoral head structural allograft and vascularized pedicled medial malleolus and fibula onlay bone grafts. At short-term 1.5-years follow-up the patient had a well-balanced and painless foot/ankle and return of a functional lower limb.

Failed Agility LP Total Ankle Replacement with Severe &gt;40 Varus Deformity Revision with Prosthesis Conversion and Soft-Tissue Procedures Alone

Achieving frontal plane alignment of the ankle joint during primary and revision total ankle replacement is essential for long-term success. This manuscript presents the revision of a failed Agility™ LP total ankle replacement system with severe > 40° varus ankle deformity that was corrected with explanation and conversion to an INBONE™ II total ankle system coupled with soft-tissue release/reconstruction employing percutaneous Achilles tendon lengthening, posterior tibial tendon intramuscular recession lengthening and modified Evans peroneus longus lateral ankle stabilization. Additionally, prophylactic tarsal tunnel release was performed to reduce potential for postoperative nerve compression. At short-term 2.5-years follow-up the patient had a well-balanced and painless foot/ ankle and return of a functional lower limb.

Outcome After Salvage Arthrodesis for Failed Total Ankle Replacement.

In cases with total ankle replacement (TAR) failure, a decision between revision TAR and salvage arthrodesis (SA) must be made. In a previous study, we analyzed revision TAR and found low functional outcome and satisfaction. The aims of the current study were to analyze SA concerning failure rate and patient-related outcome measures (PROMs). Until September 2014, a total of 1110 primary TARs were recorded in the Swedish Ankle Registry. Of the 188 failures, 118 were revised with SA (and 70 with revision TAR). Patient- and implant-specific data for SA cases were analyzed as well as arthrodesis techniques. Failure of SA was defined as repeat arthrodesis or amputation. Generic and region-specific PROMs of 68 patients alive with a solid unilateral SA performed more than 1 year before were analyzed. The first-attempt solid arthrodesis rate of SA was 90%. Overall, 25 of 53 (47%) patients were very satisfied or satisfied. Mean Self-reported Foot and Ankle Score (SEFAS) was 22 (95% confidence interval 20-24), Euro Qol-5 Dimensions 0.57 (0.49-0.65), Euro Qol-Visual Analogue Scale 59 (53-64), Short Form-36 physical 34 (31-37) and mental 50 (46-54). The scores and satisfaction were similar to those after revision TAR but the reoperation rate was significantly lower in SA (P < .05). Salvage arthrodesis after failed TAR had a solid arthrodesis rate of 90% at first attempt, but similar to revision TAR, less than 50% of the patients were satisfied and the functional scores were low. Until studies show true benefit of revision TAR over SA, we favor SA for failed TAR. Level IV, retrospective case series.

Autoinflammation Around AES Total Ankle Replacement Implants.

Failure of total ankle replacement (TAR) can be characterized by early peri-implant osteolysis even in the presence of very modest numbers of wear particles. The hypothesis of the study was that this reaction is in part mediated by autoinflammatory responses mediated via damage-associated molecular patterns (DAMPs, danger signals) and pattern-recognizing danger signal receptors (PRRs). Peri-implant tissue and control samples from 10 patients with AES implants were immunostained for hypoxia inducible factor-1α (HIF-1α), activated caspase-3, high-mobility group box 1 (HMGB1), receptor for advanced glycation end product (RAGE), and toll-like receptors TLR2 and TLR4. Results were evaluated on a 0 to 4 scale (from 0% to >50% stained area). Peri-implant tissue around failed TAR implants had a relatively high mean HIF-1α score of 3 on a scale, which however was similar in control samples. HMGB1 (a DAMP) was seen to be mobilized from nuclei to cellular cytoplasm, and the active caspase-3(+) cells were increased. All PRRs were increased in revision samples. Increased expression of HMGB1 and other danger signals together with increased PRR-dependent responsiveness could contribute to autoinflammatory peri-implantitis, multilocular cyst formation, and osteolysis in failed TAR implants. Level IV, case series.