Revision Total Ankle Arthroplasty Research Articles

ALL-COMPONENT REVISION FOR FAILED TOTAL ANKLE ARTHROPLASTY: EARLY RESULTS AND COMPLICATIONS

AimSurgical options for management of a failed ankle arthroplasty are currently limited; typically conversion to fusion is recommended with only a few patients being considered for revision replacement surgery. This paper presents our experience of revision ankle replacements in a cohort of patients with failed primary replacements.MethodA total of 18 revision TAR in 17 patients were performed in patients with aseptic loosening. The technique was performed by a single surgeon (CSK) over a 4 year period between July 2014 and August 2018 using the Inbone total ankle replacement system. Patient demographics and clinical outcomes were collected retrospectively using - MOXFQ, EQ5D, VAS pain score and patient satisfaction questionnaires.Results12 right and 6 left ankle replacements were revised in 17 patients (11 male/ 6 female). The mean age at revision was 69.1 years (range 56–81 years) with a mean BMI of 31. The mean surgical time was 171 minutes with 22% of cases requiring bone grafting. 6 patients had early wound complications, all superficial and settled with dressings. There were no deep infections, 2 patients had further surgery for exploration for possible nerve injuries. At a mean follow up of 20.6 months, 4 patients had mild/moderate ongoing pain with the majority of patients being satisfied with the outcome of their surgery.ConclusionThis study represents one of the largest group of patients reported to have undergone revision total ankle arthroplasty. Our experience shows that this results in acceptable level of complications and provides satisfactory function in most patients. We feel revision TAR is a viable option in patients with failed primary arthroplasty who wish to continue to maintain mobility at the ankle joint.

Total Ankle Arthroplasty Polyethylene Wear Varies with Implant Type and Mode of Failure

Introduction/Purpose: Polyethylene wear is a concern for failure of any joint replacement, including total ankle arthroplasty (TAA). Heterogeneity in bearing surface design among current TAA systems show no clear solution to the competing objectives of function (constraint and kinematics) and wear (contact stresses). Literature has begun to investigate polyethylene wear and damage; however, a comprehensive understanding of polyethylene wear patterns in vivo and location remains unknown. This study aims to quantify the type and severity of differing damage modes on the polyethylene insert from retrieved TAA prostheses following reoperation or revision. We hypothesized that polyethylene wear amount will be greater in TAAs that underwent revisions rather than reoperation, and that wear would vary between implants based on extent of constraint. Methods: This is a retrospective study of TAA patients (2007-2021) who underwent revision (removal of polyethylene and tibial and/or talar components) or reoperation (removal of polyethylene only) following primary TAA with a symmetric bicondylar (SB) implant with more constraint or an asymmetric bicondylar (AB) implant with less constraint. Demographics and surgical data were recorded. Retrieved polyethylene inserts were examined microscopically to characterize wear patterns according to a standardized protocol. Polyethylenes were divided into four regions on both the articular and backside surfaces: 1) lateral anterior, 2) lateral posterior, 3) medial anterior, and 4) medial posterior. Each region was graded by two independent raters on a scale of 0-3 based on severity for each of the following damage modes: 1) burnishing, 2) pitting, 3) scratching, 4) third body debris, 5) abrasion, 6) surface deformation, and 7) delamination. We assessed associations between polyethylene wear pattern and severity with implant type, revision, and reoperation. Results: 55 TAAs underwent revision (n=28) or reoperation (n=27). 30 (55%) ankles had primary TAA with AB implants (Salto Talaris) and 25 (45%) with SB implants (Inbone/Infinity) (Table 1). SB cohort had a shorter mean in-body duration (time from polyethylene implant to polyethylene explant) versus AB cohort (P=0.011). SB cohort had significantly greater overall polyethylene damage severity (P=0.007) and greater damage severity in all articular regions versus AB (P≤0.035 for all). Burnishing was significantly greater in SB versus AB (P < 0.001). TAAs that underwent revision had significantly greater overall damage severity versus reoperation (P=0.005), with significantly greater damage severity on articular medial posterior (P=0.003), lateral anterior (P=0.001), and lateral posterior (P=0.004) regions. Scratching (P=0.005), pitting (P < 0.001), and third body debris (P=0.036) were significantly greater in revision TAAs. Conclusion: While damage modes between SB and AB total ankle implants were similar, ankles with primary SB implants exhibited greater overall polyethylene damage severity in comparison to AB implants, despite being in-body for a shorter duration. In accordance with existing literature for total knee arthroplasty, this may suggest increased polyethylene damage severity with increased constraint. Irrespective of time in-body, failure for revision was associated with greater polyethylene damage than reoperation. This study provides the foundation for additional analyses to investigate radiographic alignment, mode of failure, and, ultimately, the association between polyethylene wear, peri-implant cysts and lucency, and TAA failure. Table 1 Patient demographics, revision, reoperation, and polyethylene in-body duration for the two patient cohorts: Patients with primary TAA with a symmetric bicondylar (SB) implant with more constraint and patients with primary TAA with an asymmetric bicondylar (AB) implant with less constraint. Values are expressed as means ± standard deviation for continuous variables, and frequencies with percentages for categorical variables. P-values reflect chi-square analyses and t tests between the two cohorts for categorical variables and continuous variables, respectively. SB cohort had significantly lower percentage of females, higher body weight, and shorter in-body duration. There was no significant difference in reoperations and revisions between the two groups.

Single-Center, Early Experience with the First 3D-Printed Surface, Fixed Bearing, Total Ankle Arthroplasty: A Minimum of 2-Year Follow-Up

Introduction/Purpose: As the fourth generation of total ankle arthroplasty (TAA) implants evolve, treatment solutions for end- stage ankle arthritis continue to improve. Technological advancements in CT guided planning and 3-D printing offers surgeons the ability to perform TAA with patient specific instrumentation and implants. 3-D printed components are designed to act as scaffold in hopes to facilitate early in-growth, to increase implant stability, to support long-term survivorship, and ultimately to improve the quality of life our patients. We present our early experience at a single academic center with a minimum of 2-year follow up data on the first 3-D printed, fixed bearing, TAA in the United States. We hypothesize that 3-D printed technology will demonstrate improved long-term survival and increased bony in-growth on the implant-bone interface. Methods: A retrospective review was performed on patients who underwent TAA with a minimum of 2-year clinical and radiographic data in which this 3-D printed TAA was utilized at our single academic center. Patient demographic, radiographic, and functional outcome scores were collected preoperatively, at 6 months, 1 year, and 2 years. The severity of ankle arthritis and associated deformities in patients were stratified using the COFAS classification. The primary outcomes of this study were implant survivorship, comparative analysis of preoperative and postoperative Patient Reported Outcomes Measurement Information System (PROMIS) physical function scores, VAS pain scores, radiographic development of linear radiolucency >2 mm, cystic radiolucency > 5mm, subsidence, and adverse events within 2 years of surgery. Results: Thirty patients were included with a median follow-up of 26 months (range, 24-36 months). Implant survival rate was 90%. One patient was revised to a stemmed TAA secondary to tibial subsidence. One patient required a TTC fusion secondary to Charcot collapse. One patient was revised to a staged ankle fusion secondary to periprosthetic joint infection. Two patients (6.7%) experienced linear radiolucency >2mm with tibial subsidence in which one patient required a revision TAA (mentioned above) and another who was asymptomatic. No significant cystic radiolucency >5 mm were identified. Five patients required re-operation from complications unrelated to the implant. VAS scores decreased significantly from 6 (IQR, 4-8) to 1 (IQR, 2-4) (P <.001; r=0.55). PROMIS Physical scores increased significantly from 43.6 (IQR, 33-47.7) to 50.8 (44.8-57.7)(P <.001; r=0.60). Conclusion: The utilization of this new 3-D printed, fixed bearing TAA demonstrated a ninety percent overall implant survival rate in our small cohort of patients. Further data will be required to determine the long term efficacy of this new 3-D printed implant on patient outcomes. Our early experience and complications presented in our study demonstrate that this 3-D printed TAA implant is safe and effective in the treatment of end-stage ankle arthritis.

Is There Still a Learning Curve for Primary TAA After Completing a High Volume Ankle Replacement Fellowship? A Multicentered Study

Introduction/Purpose: The learning curve in Total ankle arthroplasty(TAA) has long been reported. Surgeon experience of five to twenty-five ankle replacements have been shown to decrease various perioperative and long term complications in this complex surgery. Fellowship programs with high-volume ankle arthroplasty experiences have been suggested to mitigate this learning curve and provide benefit to early career surgeons with TAA outcomes. The purpose of this study was to evaluate the learning curve for TAA in two high-volume surgeons practices through the first three years of practice. Both surgeons completed fellowships and participated in more than 100 ankle replacements each. We hypothesized that experience during fellowship will help minimize complications and negate any learning curve previously established in the literature. Methods: Prospectively collected data was retrospectively reviewed on all patients who underwent primary TAA surgery during the first three years of clinical practice after fellowship in this IRB approved, multi-centered study. Patient demographics and clinical data, radiographic outcomes, and patient reported outcomes were collected on all patients. Patients undergoing revision TAA (as a first surgery), patients without a minimum of 2 years follow-up, and patients undergoing arthrodesis conversion to TAA were all excluded. The data was analyzed using Chi Squared test and the Moving Average Method where appropriate. All statistical analysis was performed by someone with an expertise in biostatistics. Results: Eighty-seven patients (67.8% male, avg. age 64) met inclusion criteria for the study. Average tourniquet time (111.9 min) and fluoroscopy time(106.3 secs) decreased as surgeon experience increased, with the this trend stabilizing after patient 20. Complication rate (wound complication, infection, return to OR, intraoperative fracture, etc.) was similar throughout the study period. No differences were seen in component positioning (postop AP TT angle, Postop Lateral TT angle), PROMIS Pain interference, PROMIS Depression, or PROMIS Physical function with regards to time during the study. Statistically significant differences (improvements) were seen in in the following postoperative measurements when compared to preoperative values: AP TT angle, Lateral TT angle, and PROMIS Pain Interference/Depression/Physical function. Conclusion: Learning curve as it relates to intraoperative fluoroscopy time and intraoperative tourniquet time remained even after completing a high volume TAA fellowship but clinical and PROs did not show this same trend. Radiographic measurements, complications (both intraop and postop), and patient reported outcomes did not show a time sensitive change after fellowship. Though some variables did show the maintenance of a learning curve, this multi-centered study suggests that completion of a high volume TAA fellowship can mitigate some variables in the learning curve. Study Data Summary

Revision Total Ankle Arthroplasty Using the INBONE II System.

The utilization of total ankle arthroplasty (TAA) for managing severe ankle osteoarthritis has become increasingly common, leading to a higher occurrence of revision TAA procedures because of failure of primary TAA. This study aims to examine the clinical results associated with revision TAA using the INBONE II system. Given the growing number of TAA revision procedures and a focus on motion-preserving salvage options, we evaluated our early experience with revision TAA. A retrospective analysis was conducted on a group of 60 presumed noninfected patients who underwent revision TAA with the INBONE II system. Detailed information was collected on patient demographics, implant characteristics, concurrent procedures, and complications. The implant survival was estimated using Kaplan-Meier analysis. The study revealed high complication rates but generally fair clinical outcomes for revision TAA using the INBONE II system. Complications were observed in 22 patients (36.7%), including persistent pain (n = 6), nerve injury/impingement (n = 5), infection (n = 3), fracture (n = 3), implant failure (n = 3), impaired wound healing (n = 2), and osteolysis (n = 3). The 3-year survivorship rate from reoperation was 92.0% (82.7%-100.0%) whereas the 3-year survivorship rate from major complications was 90.4% (80.8%-100.0%). We report high complication rates but generally fair clinical results for revision TAA utilizing the INBONE II system. Level IV, retrospective case series study.

Diabetes Mellitus and Total Ankle Arthroplasty Complications.

Postoperative infection, aseptic loosening, and perioperative medical complications after total ankle arthroplasty (TAA) are all devastating problems. While previous studies have shown diabetes as a risk factor predisposing patients to postoperative complications, not all literature supports this association following TAA. The goal of this study is to determine if diabetes influences midterm outcomes following TAA. An insurance database was utilized to identify patients undergoing TAA for ankle arthritis with a concurrent diagnosis of diabetes based on Current Procedural Terminology (CPT) and International Classification of Diseases, Ninth Revision (ICD-9) and Tenth Revision (ICD-10), diagnosis and procedure codes from 2010 to 2021. The postoperative outcomes of all-cause revision, periprosthetic joint infection (PJI), septic revision, and aseptic revision were compared between patients with and without diabetes with a minimum 2-year follow-up using Kaplan-Meier and multivariate Cox proportional hazards analyses. Patient demographics, comorbidities, and Charlson Comorbidity Index were analyzed via univariate and multivariate analysis. The study population included 8317 patients, 345 (4.1%) of whom had a concurrent diabetes diagnosis, who underwent TAA. After multivariate Cox proportional hazards analysis, the 5-year cumulative incidence of being coded as having PJI was 7.3% in patients with known diabetes compared to 3.9% in patients without known diabetes, with a 95% increased risk (hazard ratio [HR] 1.95, 95% CI 1.15-3.30, P = .01). Patients with diabetes also demonstrated a 5-year cumulative incidence of septic revision of 1.4% compared to 0.4% in those without, with a 363% increased risk (HR 4.63, 95% CI 1.22-17.52, P = .02). However, there was no difference in the 5-year cumulative incidence of all-cause revision TAA with 4.6% in patients with diabetes and 4.3% in those without (HR 1.29, 95% CI 0.69-2.44, P = .42). In this database, the 5-year risk of PJI and septic revision was higher among patients with diabetes compared to those without, but cumulative incidence of all-cause revision TAA was not different between groups. Level III, retrospective cohort database study.

Early Experience with a 3-D Printed Porous Surface, Fixed-Bearing, Total Ankle Arthroplasty: A Minimum of 2-Year Follow-Up

BackgroundThis is a pilot study reviewing patients undergoing ankle replacement with the 3-D printed INFINITY™ with ADAPTIS™ total ankle arthroplasty (TAA) system. MethodsA retrospective review was conducted of patients with a minimum two-year follow-up who underwent TAA with the INFINITY™ with ADAPTIS™ implant system. Outcome measures include implant survivorship, complications with subsequent reoperations, patient reported outcomes, and radiologic subsidence or radiolucency. ResultsThirty patients were included with median follow-up of 26 months (range, 24-36). Implant survival rate was 90% (27/30). Two patients experienced linear radiolucency >2mm: one required a revision TAA secondary to tibial subsidence; the other patient was asymptomatic and nonprogressive on serial radiographs. No cystic radiolucencies >5mm were identified. VAS, PROMIS PF, and FADI scores improved significantly. ConclusionTAA performed with the 3-D printed INFINITY™ with ADAPTIS™ implant technology led to ninety percent short term implant survivorship and improvement in patient reported outcomes with comparable results to other 4th generation arthroplasty systems as a treatment modality for end-stage ankle arthritis. Level of EvidenceLevel III, Retrospective cohort study, Prognostic

Early Survivorship, Clinical and Radiographic Outcomes of a Modular Augmented Revision Total Ankle Arthroplasty System.

As the number of total ankle arthroplasties (TAAs) performed annually increases, there is increased demand for modular revision implants. There is limited early survivorship and clinical outcome data for the INVISION Total Ankle Arthroplasty System (Wright Medical Technology/Stryker). This study aims to determine early implant survivorship, complications, and radiographic and patient-reported outcomes (PROs) of the INVISION implant in the revision setting. This is a single-institution retrospective review of adult patients who underwent revision TAA with the INVISION implant with minimum 2-year follow-up. Demographics, complications, radiographic data, and PROs (PROMIS) were collected. The primary outcome was implant survivorship. Secondary outcomes were reoperation, radiographic complications, and PROs. Nineteen patients underwent revision INVISION TAA with mean follow-up of 3.5 years. INVISION revision TAA was used for tibial (n = 6) or talar (n = 7) component subsidence, recurrent tibiotalar malalignment (valgus = 1, varus = 3), and postinfection bone loss (n = 2). Two-year implant survivorship was 100%. There were no reoperations. One patient had lucency of the talar component at 6 months post TAA revision with INVISION. One patient had talar subsidence at final follow-up. Two-year postoperative follow-up PROMIS domains improved significantly (P < .05). There was excellent short-term survivorship of the INVISION TAA implant, with no failures. There were significant improvements in PROs and low rates of subsidence and lucencies. The results of this study support using the INVISION implant in the revision TAA setting. Level III, retrospective cohort.

Clinical and Radiographic Outcomes of Revision Total Ankle Arthroplasty using a Revision Ankle System

Category: Ankle Arthritis; Ankle Introduction/Purpose: With the growing popularity of total ankle arthroplasty (TAA), revision surgeries are inevitable and expected to significantly increase over the next decade. Revision TAA remains a significant challenge with high complication rates. No previous study has reported on outcomes following revision TAA using an implant designed specifically for revisions. Theoretical benefits of a revision-specific ankle system include tibial and talar fixation/stability, restoration of joint height, coverage of bone loss/defects, and maximal talar coverage. The purpose of this study was to investigate radiographic and clinical outcomes at a minimum of 2 years following revision TAA using a revision-specific ankle system. Methods: Patients who underwent a revision TAA using a revision-specific ankle system (Invision, Stryker, Kalamazoo, MI) between January 2016 and December 2020 were eligible to be included in this study. Patients with less than 2-year follow-up and unwilling to return to clinic were excluded. Overall, 25 patients met inclusion criteria. Indications for revision TAA (Table 1) included talar loosening (n = 6), tibial loosening (n = 7), talar subsidence (n = 6), re-implant after infection (n = 4), instability (n = 3), periprosthetic fracture (n = 2), and severe osteolysis (n = 2). Medians and interquartile ranges (IQRs) were reported since the data was not normally distributed. Clinical and radiographic outcomes, complications, reoperations, and implant survival was recorded. Results: Implant survival was noted in 80% of patients (20/25) at a median of 3.8 years following revision TAA. Index revision was most commonly performed for implant loosening (tibia 28%, talus 24%), talar subsidence (24%), or re-implant after infection (16%). Foot and Ankle Ability Measure (FAAM) Activities of Daily Living and Sports scores were 53.9 (IQR 46.4, 71.4) and 37.5 (IQR 21.9, 46.9), respectively at final follow-up. There was evidence of talar loosening in 3 patients (12%) and talar subsidence in 5 patients (20%) on final radiographs. Reoperation rate at final follow-up was 48%, most commonly for talar loosening/subsidence (n= 2), tibial loosening (n = 3), septic TAA (n = 1), medial/lateral gutter impingement (n = 2), and instability (n = 2). Conclusion: At a minimum follow-up of 2 years, 80% of patients retained their metal revision TAA, but reoperation rates were high with 48% of patients requiring an additional procedure most commonly for implant loosening, talar subsidence, gutter impingement, or instability. Revision TAA using a revision-specific ankle system is a viable option for patients with a failed TAA. Physicians and patients should be aware that revision TAA remains a significant challenge with a high risk of complication and reoperation rates.

Revision Total Ankle Arthroplasty Outcomes in a Large Single-Center Series: Evaluation of Coronal Plane Deformity Correction and Patient Reported Measures

Category: Ankle Arthritis Introduction/Purpose: As total ankle arthroplasty (TAA) rises in popularity nationwide, the incidence of major complications and need for revision TAA will continue to increase. A better understanding of the ability to durably correct deformity and improve patient reported outcomes (PROs) in the TAA revision setting is paramount for surgeons facing the impending wave of failed TAA. Thus, the purpose of this study was to present the largest single-center case series of revision TAA to date and to evaluate improvement in PROs and maintenance of correction of coronal plane deformity in patients undergoing this procedure. Methods: This was a single-center, retrospective review of 87 revision TAAs performed between 2007 and 2022. Reoperations for cyst formations only or without metallic component exchange were excluded. The two most common implants used for revision TAA were Inbone II (n=65) and Inbone I (n=14). Mean follow-up was 2.8 ± 2.9 years. Data on patient preoperative characteristics, concurrent procedures, and postoperative complications were collected. The primary outcome measures were time to major complication, reoperation, and infection. Secondary outcomes included PROs and correction of coronal plane deformity measured from both the tibial plafond and talar articulating surface from pre- to post-operatively. Cox regression analyses were performed to compute survivorship. Results: The most common concurrent procedures performed concomitantly with revision TAA were gastrocnemius recession (n=31, 35.6%), subtalar arthrodesis (n=18, 20.7%), and talonavicular arthrodesis (n=5, 5.7%). Mean preoperative coronal plane deformity measured off both the tibial plafond and talar articular surface improved after revision TAA. 1- and 5-year survivorship from major complication, reoperation, and infection is shown in Table 2. Fourteen patients underwent subsequent revision, including TAA (n= 6, 6.9%), arthrodesis (n= 4, 4.6%), below-the-knee amputation (n= 2, 2.3%), or implantation of an antibiotic spacer (n= 2, 2.3%). At one-year postoperatively, mean VAS pain score, SF36, and AOFAS Hindfoot score was 18.2 ± 16.0, 73.0 ± 13.3, and 68.8 ±:9.3, respectively, representing an improvement in PROs after revision TAA. Conclusion: In the largest single-center series of patients undergoing single or double component exchange revision TAA, we demonstrate durable improvements in coronal plane deformity measured off both the tibial plafond and talar articular surface. We also noted 63.0% survivorship with regards to reoperation and improvements in average PROs across the cohort. Overall, revision TAA is a successful procedure, but is associated with higher failure rates at 5 years than primary TAA.

Patient Reported Outcomes Before and After Revision Total Ankle Arthroplasty Done In the First Two Years of a Single Surgeons Practice

Category: Ankle Arthritis; Ankle Introduction/Purpose: As Total Ankle Arthroplasty (TAA) volume continues to grow nationally, so is the need for revision TAA surgery. A foot and ankle surgeon fresh out of fellowship is likely to encounter these challenging cases soon after beginning practice. The learning curve for ankle replacement has been demonstrated in multiple studies but no such study exists for revision TAA due to the relative infrequency of this procedure. The experience of one high volume revision TAA surgeon in the first two years after fellowship is reviewed in this study. Radiographic, clinical, and patient reported outcomes are analyzed in this study. Methods: In this IRB approved study, we retrospectively reviewed prospectively collected data on 18 patients who underwent Revision Total Ankle Arthroplasty Surgery from January 1, 2018, to January 1, 2021. Patient-reported outcome (PRO) measures including PROMIS depression, physical function and pain interference CATs taken preoperatively and then at specific post- operative intervals were collected on all patients. Radiographic and clinical results were also reviewed. Patients being revised, whether single stage or two-stage, for infection were excluded. Patients converted from ankle arthrodesis to ankle replacement were omitted. Student t tests, chi-square test, and nonparametric alternatives (p &lt;.05) we used. Results: Eighteen patients ( Average age 65.5, 50% male) underwent revision TAA average follow up 25 months. Aseptic loosening (50%) was the most common cause for revision followed by component malpositioning (28.8%). The Scandanavian Total Ankle Replacement was the most commonly revised implant in this study 83.3%. Radiographic parameters (Tibiotalar angle Tibial component positioning) improved after revision TAA. Average Promis physical function improved from 41.18 pre-op to 47.77 (p.078), depression improved from 57.64 pre-op to 49.67(p .025*), and pain interference improved from 61.3 preop to 50.55 (p .045*) after revision TAA. No differences were seen in any outcome measure with regards to time from fellowship, when assessing for a learning curve. See attached table for complete list of results. Conclusion: Revision TAA is a technically challenging procedure. One which will continue to be more and more common as ankle replacement continues to replace arthrodesis as the preferred treatment for ankle arthritis. This study did not identify a learning curve for revision total ankle arthroplasty. Outcomes were similar independent of time after fellowship the cases occurred. Patient reported outcomes, clinical outcomes, and radiographic outcomes all improved in this cohort after revision TAA.

A Systematic Review of Outcomes of Total Ankle Arthroplasty with INBONE II

Category: Ankle Arthritis; Ankle Introduction/Purpose: The INBONE II is a fixed-bearing implant with a stemmed tibial component commonly used for total ankle arthroplasty (TAA). Despite its frequent use and previously reported outcomes within individual clinical studies, no study has systematically reviewed outcomes of TAA with this implant. The purpose of this study was to perform a systematic review of the literature and report on outcomes of TAA with the INBONE II. Methods: A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines. Databases searched included PubMed, Google Scholar, SCOPUS and CINAHL from database date of inception through February 28th, 2023. Clinical studies of INBONE II outcomes in peer reviewed journals were included. Outcomes included were survivorship, patient reported outcome measures (PROMs), and complications. Outcome results were compiled using weighted averages when possible. This review of 26 articles included 808 patients with 667 primary TAA and 141 revision TAA. Results: Survivorship, with failure defined as metal component revision, was 97.8% at an average follow-up of 49 months (range, 14-85.4 months) and 94.2% at an average follow-up of 25.7 months (range, 9.1-47.5) months for primary and revision TAA respectively. Complication rates for primary TAA included: 3.8% intra-operative fractures, 2.5% post-operative fractures, 1.8% deep infection, 8.0% wound complications, 1.6% rate of poly exchange, and 1.6% nerve injuries. Revision TAA complication rates included: 12.3% intra-operative fractures, 6.9% wound complications, 3.3% deep infections, and a 5.5% incidence of nerve injury. Average PROMs for primary TAA included: AOFAS American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score improved 41 points, visual analog scale (VAS) scores decreased 5.9, and patient satisfaction of 92.6%. Revision TAA PROMs were not consistently reported. Conclusion: This study is the largest compilation of INBONE II outcomes and survivorship. Primary and revision TAA with the INBONE II results in satisfactory improvement in PROMs and low complication rates. The overall survivorship is 97.8% and 94.2% at an average follow-up of 49 months (range, 14-85.4 months) and 25.7 months (range, 9.1-47.5) for primary and revision total ankle arthroplasty respectively. These findings support continued use of this implant in primary and revision TAA.

The Invision Talar Component as a Revision Total Ankle Arthroplasty Option: Analysis of Early Outcomes

Category: Ankle; Other Introduction/Purpose: The Invision talar component was launched in 2018 as a revision total ankle arthroplasty (TAA) specific option geared towards avoiding further subsidence when poor talar bone stock is present. Due to the recency of the market- availability of the Invision, studies evaluating the efficacy of the implant, even in the short-term, are lacking. Thus, the purpose of this study was to present the early-term outcomes of a series of patients undergoing revision TAA with the use of the Invision talar component. Methods: This was a single-center, retrospective review of 28 patients undergoing revision TAA with the Invision talar component and Inbone II tibial component (Wright Medical; Memphis, Tennessee) performed between 2007 and 2022. Mean follow-up was 1.3 ± 0.93 years. Data on patient preoperative characteristics, postoperative complications, and survivorship were collected. The primary outcome measures were time to major complication, reoperation, and infection. Results: The most common concurrent procedures performed with revision TAA with the Invision talar component were gastrocnemius recession (n=14, 50%), subtalar arthrodesis (n=3, 10.7%) and cotton osteotomy (n = 1, 3.6%). The mean preoperative coronal deformity off the tibia was 4.07 ± 3.06 degrees for varus and 3.67 ± 4.36 degrees for valgus deformities, respectively, and postoperatively, was 1.67 ± 2.16 degrees for varus and 2.00 ± 3.48 degrees for valgus. The mean preoperative coronal plane deformity off the talus was 4.83 ± 6.68 degrees for varus and 4.22 ± 4.21 degrees for valgus, respectively, and postoperatively, was 1.23 ± 2.45 degrees for varus and 2.32 ± 3.93 degrees for valgus. The survivorship from any complication, major complication, reoperation, and infection is shown in Table 2. Conclusion: In a series of 28 patients undergoing revision TAA with the Invision talar component and Inbone II tibial component, we demonstrate a survivorship of 92.7% at 1-year follow up. The Invision appears to have a reasonable safety profile in this non- designer series. The implant compares favorably with others utilized in the revision TAA setting at the early-term, but further studies evaluating mid-and long-term outcomes are required to fully assess the efficacy of the Invision.

Early Survivorship, Clinical and Radiographic Outcomes Following Primary and Revision Total Ankle Arthroplasty using a Modular Augmented Revision (INVISION) Implant

Category: Ankle Arthritis; Ankle Introduction/Purpose: As the number of total ankle replacements (TAR) performed annually increases, there is an increased demand for implants that can be used in revision scenarios when primary TARs fail. As indications for TAR expand, there is increased reliance on modular systems to treat challenging conditions including bone loss, avascular necrosis, and instability. The INVISION Total Ankle Arthroplasty System (Wright Medical Technology/Stryker, Memphis, TN), released in 2018, includes modular augmented tibial trays and talar plates of varied heights to compensate for bone loss. There is limited data on early survivorship and clinical outcomes of the INVISION. This novel study aims to determine the early implant survivorship, complications, patient-reported outcomes (PROMIS), and radiographic outcomes of the INVISION implant used in both the primary and revision arthroplasty setting. Methods: This study is a single-institution retrospective review of adult patients who underwent primary or revision TAR with the INVISION implant with minimum 2-year follow-up. Demographics, reason for use of INVISION, surgical data, complications, pre- operative and 2 year post-operative radiographic data, and pre-operative and 2-year post-operative patient-reported outcome scores were collected. The primary outcome was survivorship (retention of both tibial/talar components at final follow-up). Secondary outcomes were reoperation (return to OR with retention of both tibial and talar components), radiographic complications (peri-implant lucency, cysts, or subsidence), and patient-reported outcomes (PROMIS pre-operative and 2-year post-operative). PROMIS scores were collected across the following domains: physical function, pain interference, pain intensity, global mental health, and depression score. Results: Twenty-six patients (primary=7; revision=19) underwent INVISION TAR (mean age 62 years, weight 81.kg, BMI 29.3 kg/m2, 15/26 male) with mean follow-up 3.5 years. Reason for INVISION primary TAR included tibial (n=1) or talar (n=5) bone loss, and take-down fusion (n=1); INVISION revision TAR was used for tibial (n=6) or talar (n=7) component subsidence, recurrent tibiotalar malalignment (valgus=1, varus=3), and post-infection bone loss (n=2). Two-year implant survivorship was 100%. There were 2 reoperations (7.7%): 1 gutter debridement and 1 irrigation, debridement and polyethylene exchange for infection. Two-year follow-up PROMIS domains improved significantly (p &lt; 0.05) from pre-operative in both the primary (pain interference, pain intensity) and revision cohorts (pain interference, pain intensity, global physical function). Two-year radiographic follow-up yielded 1 tibial peri-implant lucency and 1 tibial cyst. Conclusion: In this single-institution series, there was excellent short-term survivorship of the INVISION TAR implant with no failures in primary or revision cases. There were significant improvements in patient-reported outcomes scores. There were low rates of peri-implant lucencies and cysts. The results of this study support the use of the INVISION implant in both the complex primary and revision TAR setting. INVISION may offer an alternate surgical solution to fusion, custom printed cage implants, and total talus replacement in this complex patient population. Further research and follow-up data are warranted to report the longer-term outcomes and survivorship of this implant.

Risks of Increased Operative Time and Longer Hospital Stays Based on Age in Total Ankle Arthroplasty

Category: Ankle Arthritis Introduction/Purpose: Total joint arthroplasty is increasingly being performed in younger individuals across the United States. While age-specific outcomes have been evaluated in total hip and knee replacements, the data are not as clear for total ankle arthroplasty (TAA). The purpose of this study was to analyze TAA outcomes and complications by age to improve shared decision-making when considering ankle replacements. Methods: A total of 1,619 primary and revision TAAs from 2012-2020 were collected and included from the National Surgical Quality Improvement Program. Patients were stratified by age into groups less than 55, between 55-70, and greater than 70 years of age. Demographics, medical comorbidities, ASA class, operative time, 30-day complications, and comorbid conditions were compared by univariable analysis. Multivariable analysis was used to analyze readmission rates, reoperation rates, operative time, and hospital length of stay. Results: By univariable analysis, patients greater than 70 have significantly more comorbidities when compared to patients younger than 55. Younger patients have a significantly longer hospital stay, with an average of 1.64 days for those younger than 55 compared to patients 55-70 (1.50 days) and patients older than 70 (1.38 days, p&lt; 0.001). Younger patients also have a significantly longer operative time and a higher risk of still being in the hospital after 30 days (p &lt; 0.001, p=0.034). By multivariable analysis, patients 55-70 have a statistically lower risk of readmission compared to the other two cohorts (p = 0.043). Conclusion: As the incidence of total ankle arthroplasty increases across all ages, it is important to understand specific risks for each age group. Patients younger than 55 experience higher operative times and longer lengths of stay. Patients between 55-70 have a significantly lower risk of reoperation but longer hospital stays. Patients older than 70 tend to have lower reoperation rates, lower readmission rates, and shorter operative times.

Intermediate Term Clinical Outcomes in Total Ankle Arthroplasty: The CU Total Ankle Registry

Category: Ankle Arthritis; Ankle Introduction/Purpose: Total ankle arthroplasty (TAA) is a common procedure to treat end stage ankle osteoarthritis. Despite recent increase in popularity, there is limited literature assessing clinical and patient-reported outcomes (PROs) in TAA procedures using 5 current generation implants. These measures are an important tool for physicians to better assess patient performance in daily activities. The purpose of this study is to characterize both PROs and clinical outcomes in primary and revision TAA surgeries using current generation prostheses performed by non-design surgeons at a single institution. Methods: Our institution maintains a prospective outcomes registry for patients undergoing TAA at our institution. Patient demographics, relevant case information, PROs and complications are collected. Collected PROs include PROMIS Physical Function (PF), Pain Interference (PI), Depression, Global Physical Health (GPH), Global Mental Health (GMH), and Foot and Ankle SANE. Records are categorized as a primary TAA, or revision involving either a polyethylene only exchange or complete hardware removal and replacement. Differences between groups were determined non-parametrically using Mann-Whitney U tests. In all statistical tests, a p value of less than 0.05 was considered significant. Results: A total of 259 patients were included for analysis; 223 primary and 36 partial or full revision. Average length of stay was 1.6 ± 1 days. There were 18 reoperations (6.95%), with no implant failures within 1 year. Five patients underwent implant revision at an average of 2.5 years. Of these, one was related to delayed infection at year 3, two due to hardware failure in year 2, and 2 polyethylene exchanges in years 2 and 5. All physical health PRO measures showed significant improvements post-operatively (p &lt; 0.0001). Patients reported significant reductions in pain following TAA at 3-months (Figure 1a), and significant improvement of physical function after 6-months (Figure 1b). There were no significant changes in Depression or GMH (Figure 1d). Conclusion: Total ankle arthroplasty is a safe and effective procedure for end-stage ankle arthritis. Patients experience improvement in all physical health PRO metrics at all post-operative time points after 3 months. Complication and early failure rates are lower than that reported in the literature. Long term outcomes and implant longevity will be tracked using the CU Total Ankle Registry. Total ankle arthroplasty improves quality of life in patients suffering from ankle osteoarthritis. Further follow-up and patient enrollment in the CU Total Ankle Registry will help us to identify risk factors for complications and define implant lifespan.

Wear Rates of Highly Cross-Linked Polyethylene in Total Ankle Arthroplasty at Mean 7-Year Follow- up

Category: Ankle Arthritis; Ankle Introduction/Purpose: Polyethylene (PE) wear particles have been shown to be a contributing factor of osteolysis and aseptic loosening. The use of highly cross-linked polyethylene (HXLPE) liners has been proven to reduce wear rates in hip and knee arthroplasty. To date, no clinical study has investigated the in vivo wear rates of HXLPE in total ankle arthroplasty (TAA). Therefore, the purpose of our study was to evaluate mid- and long-term outcomes and HXLPE wear rates in primary TAA. Methods: We retrospectively identified 49 patients who underwent primary TAA with HXLPE liners at a minimum of 5-year follow up. The average age was 65 years, 57.1% female, and average body mass index was 28.7 kg/m2. Polyethylene wear rates at final follow up were assessed using anteroposterior ankle radiographs and a validated computer assisted software. In addition, overall implant survivorship and complications were recorded. Results: The average polyethylene linear wear rate was 0.073 mm/year (SD, +/- 0.027) at mean 7.6 year (range, 5.1 to 12.2) follow up. Further analysis of patients with greater than 10 year follow up (n=8) demonstrated a linear wear rate of 0.06 mm/year (SD, +/- 0.02) at mean 11.1 year (range, 10.0 to 12.2). There were no instances of linear fracture or dissociation. Survivorship was 98.0% with 1 patient requiring removal of hardware and revision TAA secondary to failure of distal tibial osteotomy which was performed at index procedure. The rate of reoperation was 12.2% (n=6) with the most common indication being symptomatic ankle impingement treated with peri-implant cyst excision, exostectomy, and debridement (n=4). Conclusion: Highly crosslinked polyethylene liners in primary TAA demonstrated low in vivo wear rates and no cases of liner mechanical failures. In addition, our cohort demonstrated low complication and reoperation rates and exceptional survivorship at mid to long-term follow up. Therefore, the use of HXLPE liners is a viable option for surgeons performing TAA.

Fusion after a failed primary total ankle arthroplasty.

When a total ankle arthroplasty (TAA) fails, it can be converted to a fusion or a revision arthroplasty. Despite the increasing numbers of TAAs being undertaken, there is little information in the literature about the management of patients undergoing fusion following a failed TAA. The primary aim of this study was to analyze the survival of fusions following a failed TAA using a large dataset from the National Joint Registry (NJR). A data linkage study combined NJR and NHS Digital data. Failure of a TAA was defined as a fusion, revision to a further TAA, or amputation. Life tables and Kaplan-Meier graphs were used to record survival. Cox proportional hazards regression models were fitted to compare the rates of failure. A total of 131 patients underwent fusion as a salvage procedure following TAA. Their mean age was 65.7 years (SD 10.6) and 73 (55.7%) were male. The mean follow-up was 47.5 months (SD 27.2). The mean time between TAA and fusion was 5.3 years (SD 2.7). Overall, 32 (24.4%) underwent reoperations other than revision and 29 (22.1%) failed. Of these 24 (18.3%) underwent revision of the fusion and five (3.8%) had a below-knee amputation. No patients underwent conversion to a further TAA. Failure usually occurred in the first three postoperative years with one-year survival of fusion being 96.0% (95% confidence interval (CI) 90.7 to 98.3) and three-year survival in 69 patients being 77.5% (95% CI 68.3 to 84.4). Salvage fusion after a failed TAA shows moderate rates of failure and reoperations. Nearly 25% of patients required revision within three years. This study is an extension of studies using the same methodology reporting the failure rates and risk factors for failure, which have recently been published, and also one reporting the outcome of revision TAA for a failed primary TAA, using the same methodology, which will shortly be published.

Ballooning Periprosthetic Osteolysis Related to Crystalline Arthropathies Following Total Ankle Arthroplasty: A Case Series

Category: Ankle Arthritis; Basic Sciences/Biologics Introduction/Purpose: From 2009-2019, there has been a 120% increase in the incidence of total ankle arthroplasty (TAA) in the United States. With the rise in primary TAA, future increases in revision TAA cases is anticipated. Aseptic loosening with periprosthetic osteolysis continues to account for a significant number of revisions. While several factors may contribute to the pathophysiology of osteolysis, an underlying inflammatory response surrounding TAA implants may play a primary role. It is well known that monosodium urate (gout) and calcium-pyrophosphate (pseudo-gout) crystals evoke a highly inflammatory response and may involve the foot and ankle joints. However, the effect of these conditions following TAA has not yet been reported. We present a small case series of patients with ballooning osteolysis following TAA with confirmed crystalline arthropathy. Methods: This is a retrospective study from a single academic institution looking at patients who underwent TAA revision surgery for periprosthetic osteolysis and concern for aseptic loosening. Revision surgeries were performed by three orthopedic foot and ankle fellowship trained surgeons. Case characteristics, including pre-operative imaging, clinical presentations, intra-operative findings and surgical treatments performed were analyzed and presented in this small case series. Results: We report 5 patients whom underwent revision surgery for ballooning periprosthetic osteolysis following TAA. Intra- operative pathology samples from periprosthetic cysts returned positive for monosodium urate (MSU) or calcium pyrophosphate (CPP) crystalline deposition (1 MSU and 4 CPP) in all 5 patients. Final intra-operative cultures were all negative for infection. Upon gross intra-operative inspection, all polyethylene liners were considered to be normal without abnormal wear characteristics. Periprosthetic cysts were isolated to the tibial component in 2 patients and involved both the tibial and talar components in 3 patients. Staged TAA revision was performed in 2 patients. Bone cyst curettage, bone grafting and polyethylene liner exchange was performed in 3 patients. Conclusion: Periprosthetic osteolysis is a known complication following TAA and often leads to implant loosening, functional disability and subsequent revision surgery. An objective strategy for management of this condition has not been agreed upon amongst orthopedic foot and ankle surgeons, as uncertainty remains surrounding the pathophysiology of osteolysis in TAA. To our knowledge, we are the first to describe a small case series of patients with crystalline arthropathy as a potential cause for periprosthetic osteolysis following TAA. Future prospective studies are warranted to better elucidate this potential cause of TAA failure.

Revision of total ankle arthroplasty: Survival and medium-term functional results

BackgroundThe objective of this study was to analyze the results and survivorship of total ankle arthroplasty (TAA) revision surgery with standard (Salto Talaris®) or revision (Salto Talaris XT®) implants. MethodsBetween January 2005 and December 2017, all patients undergoing TAA revision at our hospital were included. Indications for revision, type of surgery performed, improvement in function assessed with the AOFAS score, occurrence of complications and implant survival at last follow-up were analyzed. ResultsIn the end, 25 TAA patients who had undergone revision (11 unipolar, 14 bipolar) were included. The mean follow-up time was 5.1 ± 1.9 years. At the last follow-up, function was improved compared to the preoperative AOFAS score (51.3 ± 17.5 vs. 83.5 ± 10.1; p < .001), but not plantar flexion (17.5 ± 5.7 vs. 15.4 ± 7.1; p = 0.28) or dorsal flexion (7 ± 5.6 vs. 8.3 ± 4.9; p = 0.3). Complications occurred in six patients (24 %) that led to reoperation: three infections, one lateral impingement, one implant malposition, and one hindfoot alignment disorder. At the last follow-up, implant survival was 96 %, but the probability of survival without reoperation was 78.7 ± 8.5 % at 4 years. ConclusionTAA revision by arthroplasty is feasible, produces good functional results in the medium term, but has a high risk of complications. The challenge of revision TAA is managing the loss of bone stock and anchoring the new implants.