Primary Total Ankle Arthroplasty Research Articles

Association of Timing of Hindfoot Arthrodesis and Early Reoperation Rates for Total Ankle Arthroplasty.

Prior literature has demonstrated that ipsilateral hindfoot arthrodesis may increase the risk for reoperation after total ankle arthroplasty (TAA) and that simultaneous hindfoot arthrodesis with TAA could result in short-term clinical and radiologic improvements. The purpose of this study is to compare the reoperation rates after TAA with prior hindfoot arthrodesis vs simultaneous arthrodesis and TAA. Patients who underwent primary TAA were identified in the PearlDiver database. Patients were sorted into 2 study cohorts: hindfoot arthrodesis prior to TAA and simultaneous arthrodesis and TAA. Propensity matched control cohorts were identified for each study group. Multivariate analysis was conducted to account for any confounding variables and covariates when identifying differences in complications between cohorts. 297 patients underwent TAA with prior hindfoot arthrodesis and 174 underwent TAA and hindfoot arthrodesis concurrently. The incidence of reoperation (13.8% vs 5.2%, P < .001) and infection (12.6% vs 5.9%, P = .011) for the simultaneous cohort was higher when compared to the matched control cohort. In contrast, there was no statistically significant difference when comparing the prior arthrodesis cohort to the matched control cohort in reoperation rates (5.1% vs 4.7%, P = .787) or infection rates (4.4% vs 4.8%, P = .734). Those undergoing simultaneous procedures had increased incidences of reoperation, wound complications, infection, and emergency department visits (P < .0167) when compared to the TAA with prior arthrodesis cohort. Patients undergoing TAA and hindfoot arthrodesis concurrently were found to have higher rates of reoperation and infection when compared to the matched control cohort . In contrast, there was no difference in these rates in patients undergoing TAA with prior hindfoot arthrodesis compared with their matched control cohort. Patients undergoing simultaneous procedures had increased rates of reoperations, wound complications, infection, and emergency department visits compared to the TAA with prior arthrodesis cohort. Level III, retrospective comparative database study.

Bone grafting for periprosthetic bone cysts following total ankle arthroplasty.

The purpose of this study was to assess the success rate and functional outcomes of bone grafting for periprosthetic bone cysts following total ankle arthroplasty (TAA). Additionally, we evaluated the rate of graft incorporation and identified associated predisposing factors using CT scan. We reviewed a total of 37 ankles (34 patients) that had undergone bone grafting for periprosthetic bone cysts. A CT scan was performed one year after bone grafting to check the status of graft incorporation. For accurate analysis of cyst volumes and their postoperative changes, 3D-reconstructed CT scan processed with 3D software was used. For functional outcomes, variables such as the Ankle Osteoarthritis Scale score and the visual analogue scale for pain were measured. Out of 37 ankles, graft incorporation was successful in 30 cases. Among the remaining seven cases, four (10.8%) exhibited cyst re-progression, so secondary bone grafting was needed. After secondary bone grafting, no further progression has been noted, resulting in an overall 91.9% success rate (34 of 37) at a mean follow-up period of 47.5 months (24 to 120). The remaining three cases (8.1%) showed implant loosening, so tibiotalocalcaneal arthrodesis was performed. Functional outcomes were also improved after bone grafting in all variables at the latest follow-up (p < 0.05). The mean incorporation rate of the grafts according to the location of the cysts was 84.8% (55.2% to 96.1%) at the medial malleolus, 65.1% (27.6% to 97.1%) at the tibia, and 81.2% (42.8% to 98.7%) at the talus. Smoking was identified as a significant predisposing factor adversely affecting graft incorporation (p = 0.001). Bone grafting for periprosthetic bone cysts following primary TAA is a reliable procedure with a satisfactory success rate and functional outcomes. Regular follow-up, including CT scan, is important for the detection of cyst re-progression to prevent implant loosening after bone grafting.

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 &lt; 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 &lt; 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.

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

Does Timing of Subtalar Arthrodesis Affect Reoperation or Revision Rates for Total Ankle Arthroplasty?

Introduction/Purpose: The incidence of primary total ankle arthroplasty (TAA) in the treatment of end-stage ankle arthritis has increased substantially over the last decade. TAA may be performed alone or in conjunction with additional procedures including subtalar (ST) or triple arthrodesis as end-stage ankle arthritis is often associated with degenerative disease affecting neighboring joints. Prior literature has demonstrated that the ipsilateral hindfoot arthrodesis may increase the risk for revision after TAA and that simultaneous ST arthrodesis with TAA could result in significant short term clinical and radiologic improvements. However, there is limited research comparing staged versus simultaneous hindfoot arthrodesis with concomitant TAA. The purpose of this study is to compare the reoperation rates after TAA with simultaneous hindfoot arthrodesis versus staged hindfoot arthrodesis followed by TAA. Methods: Patients who underwent primary TAA from 2015-2022 were identified in the PearlDiver database using international classification of diseases (ICD) and current procedural (CPT) codes. Patients were only selected if they contained 1-year database follow-up after the index TAA. Patients were sorted into three cohorts: (1) primary TAA without any history of hindfoot arthrodesis (control), (2) those with staged hindfoot arthrodesis prior to TAA, and (3) those with hindfoot arthrodesis at the same time as TAA. Demographic characteristics including age, gender, and Charlson Comorbidity Index (CCI) were assessed for each cohort. The 1-year rate of reoperation and revision were the primary outcomes of this study. Univariate analysis using chi- square tests and student T-tests were performed to analyze any differences in patient demographics, comorbidities, and complications. Multivariate analysis using logistic regression was subsequently conducted to account for any confounding variables and covariates. Results: 9,912 patients underwent TAA without prior hindfoot arthrodesis, 297 patients underwent TAA with prior hindfoot arthrodesis and 174 with hindfoot arthrodesis concurrently with TAA. The incidences of reoperation (OR 3.52, 12.6% vs. 3.9%, P&lt;0.001) and revision (OR 3.66, 4.0% vs. 1.1%, P=0.001) were higher in the simultaneous cohort when compared to the control. However, there were no statistically significant differences in rates of reoperation (OR 0.96, 4.0% vs. 3.9%, P= 0.891) or revision (OR 1.94, 2.4% vs. 1.1 %, P= 0.095) when comparing staged hindfoot arthrodesis to the control. Conclusion: Patients undergoing concurrent hindfoot arthrodesis with TAA had a 3.5 times higher odds of reoperation and revision when compared to the control. Patients undergoing staged procedures did not demonstrate a difference in revision or reoperation rates when compared to the control. Staged hindfoot arthrodesis and TAA may be an effective option in treating complex end-stage ankle and hindfoot arthritis whereas a simultaneous approach may lead to higher rates of complications.

Discrepancies Between Intraoperative and Postoperative Ankle Motion Measured for Anterior-Approach Total Ankle Arthroplasty.

Although intraoperative ankle motion serves as a foundational reference for anticipated motion after surgery and guides the addition of procedures to enhance ankle motion in total ankle arthroplasty (TAA), the relationship between intraoperative and postoperative ankle motion remains unclear. This study aimed to investigate the discrepancy between intraoperative and postoperative ankle range of motion (ROM) following TAAs using the anterior-approach, fixed-bearing systems. This study retrospectively reviewed 67 patients (67 ankles) who underwent primary TAA at a single institution. Three different types of anterior-approach, fixed-bearing TAA systems were included. Intraoperative fluoroscopy was used to document the maximal dorsiflexion and plantar flexion at the end of the case. Standardized weightbearing maximum dorsiflexion and plantar flexion sagittal radiographs were obtained pre- and postoperatively, following a previously described method. The motion between 3 different time points (preoperative, intraoperative, and postoperative [mean 11.4 months]) was compared using pairwise t tests, and their differences were quantified. The mean total tibiotalar ROM was 38.1 degrees (SD 7.8) intraoperatively, and the postoperative total tibiotalar ROM was 24.2 degrees (SD 9.7) (P < .001), indicating that a mean of 65.3% (SD 26.7) of the intraoperative motion was maintained postoperatively. Intraoperative dorsiflexion (mean 11.6 [SD 4.5] degrees) showed no evidence of difference from postoperative dorsiflexion (mean 11.4 [SD 5.8] degrees, P > .99), indicating that a median of 95.6% (interquartile range: 66.2-112) of the intraoperative maximum dorsiflexion was maintained postoperatively. However, there was a significant difference between intraoperative plantarflexion (mean 26.4 [SD 6.3]) and postoperative plantarflexion (12.8 [SD 6.9] degrees, P < .001), indicating a mean 50.6% (SD 29.6) of intraoperative motion maintained in the postoperative assessment. There was an improvement of 2.5 degrees in the total tibiotalar ROM following TAA with statistical significance (P < .043). This study revealed a significant difference between intraoperative ankle ROM and ankle ROM approximately 1 year after anterior-approach, fixed-bearing TAA, mainly due to plantarflexion motion restriction. Minimal difference in dorsiflexion suggests the importance of achieving the desired postoperative dorsiflexion motion during the surgery using the best possible adjunct procedures. Level IV, case series.

Effects of Travel Distance on Complications and Outcomes in Total Ankle Arthroplasty.

Owing to the last decade's increase in the number of total ankle arthroplasty (TAA) procedures performed annually, there is a concern that the disproportionate distribution of orthopaedic surgeons who regularly perform TAA may impact complications and/or patient satisfaction. This study examines patient-reported outcomes and complications in TAA patients who had to travel for surgery compared to those treated locally. This is a single-center retrospective review of 160 patients undergoing primary TAA between January 2016 and December 2018, with mean age 65 (range: 59-71) years, mean body mass index (BMI) 28.7 kg/m2, 69 (43.1%) females, and mean 1.5 (SD = 0.51) years follow-up. Patients were grouped by distance traveled (<50 miles [n = 89] versus >50 miles traveled [n = 71]). There were no significant differences in rate or type of postoperative complications between the <50 mile group (16.9%) and the >50 mile group (22.5%) (P = .277). Similarly, there were no significant difference in postoperative PROMIS scores between the groups (P = .858). Given uneven distribution of high-volume surgeons performing TAA, this is important for patients who are deciding where to have their TAA surgery and for surgeons on how to counsel patients regarding risks when traveling longer distances for TAA care.Levels of Evidence: Level III: Retrospective Cohort Study.

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.

Outcomes After Total Ankle Arthroplasty in Patients Aged ≤50 Years at Midterm Follow-up.

Ankle arthritis differs from arthritis of the hip and knee in that 80% is posttraumatic and thus often occurs in a younger patient population. The literature supporting total ankle arthroplasty (TAA) in younger patients has increased over recent years and has bolstered the argument that in the short term, TAA in younger patients has successful outcomes that are comparable to older, lower-demand patients.The purpose of our study was to evaluate patient-reported outcomes (PROs) and implant survivorship at midterm after primary TAA in patients ≤ 50 years of age at the time of surgery. A retrospective chart review was conducted of patients ≤ 50 years of age who underwent primary TAA at a single institution from 2000 to 2017. Patient demographics, outcome measures, and complications were recorded. All patients had a minimum clinical follow-up of 5 years. PRO measures were evaluated at preoperative, 1-year postoperative, and final follow-up visits. Paired t tests were performed to compare individual patient changes in PROs from preoperative. Implant survivorship was evaluated based on need for revision of either the tibial or talar component. The need for additional surgery related to the TAA was also evaluated. A total of 58 patients were included. The average age at the time of the index surgery was 43.3 years (range 22-50 years). All patients had a minimum follow-up of 5 years with a mean follow-up of 8.8 years. A total of 11 patients required additional surgery related to their TAA. Six patients (10.3%) required bone grafting of peri-implant cysts, 3 patients (5.2 %) required gutter debridement, and 1 patient underwent complete revision of metal components. Mean visual analog scale, 36-item Short Form Health Survey, Short Musculoskeletal Function Assessment, and American Orthopaedic Foot & Ankle Society hindfoot scores significantly improved from preoperative to 1-year postoperative and final postoperative follow-up. The patients aged ≤50 years treated with a TAA whom we have been able to observe for a minimum of 5 years showed generally maintained improvement in functional scores and thus far have had a relatively low rate of secondary surgeries.Level of Evidence:Level III, retrospective cohort study.

Survival and risk assessment in revision arthroplasty of the ankle.

Implant failure has become more common as the number of primary total ankle arthroplasties (TAAs) performed has increased. Although revision arthroplasty has gained attention for functional preservation, the long-term results remain unclear. This study aimed to assess the long-term outcomes of revision TAA using a mobile-bearing prosthesis in a considerably large cohort; the risk factors for failure were also determined. This single-centre retrospective cohort study included 116 patients (117 ankles) who underwent revision TAA for failed primary TAA between July 2000 and March 2010. Survival analysis and risk factor assessment were performed, and clinical performance and patient satisfaction were evaluated preoperatively and at last follow-up. The mean duration from initial revision TAA to last follow-up was 15.0 years (SD 3.0; 11.2 to 20.5). The cumulative survival rates of the revised ankles were 81% (95% confidence interval (CI) 74% to 88%), 74% (65% to 82%), and 70% (61% to 79%) at five, ten, and 15 years, respectively. Comorbidities prior to primary TAA, aseptic loosening, instability, or grafting of cysts were found to be the most common risk factors for secondary revision. The median value for preoperative pain, as assessed using the visual analogue scale, declined from 6 (interquartile range (IQR) 5 to 8) to 2 (IQR 0 to 5) (p < 0.001) and the mean American Orthopaedic Foot and Ankle Society ankle-hindfoot score improved from 43 (SD 17) preoperatively to 70 (SD 20) (p < 0.001) at last follow-up. Revision TAA offers acceptable survival rates after 15 years; it therefore offers a valuable option for treatment of implant failure in carefully selected cases. Although patient-reported outcomes improve substantially, the degree of improvement reported following primary TAA is not achieved.

Long-Term Survival Analysis of 5619 Total Ankle Arthroplasty and Patient Risk Factors for Failure.

Total ankle arthroplasty (TAA) has higher complication and failure rates compared to other surgical joint replacement procedures despite technological advances. This study aimed to find the long-term survivability of the TAA procedure and identify the patient risk factors for failure with one of the largest cohorts of patients in the literature. This retrospective cohort study involving cases between 2007 and 2018 analyzed patients who received an index primary TAA procedure in Korea. A total of 5619 cases were included in the final analysis. The TAA failure was defined as either a case with revision arthroplasty or a case with TAA implant removal and arthrodesis performed after primary TAA. During the study period, the 5-year survival rate was 95.4% (95% CI, 94.7-96.1%), and the 10-year survival rate was 91.1% (95% CI, 89.1-93.1%). A younger age (<55 years, adjusted hazard ratio [AHR], 1.725; 55-64 years, AHR, 1.812; p < 0.001 for both), chronic pulmonary disease (AHR, 1.476; p = 0.013), diabetes (AHR, 1.443; p = 0.014), and alcohol abuse (AHR, 1.524; p = 0.032) showed a significantly high odds ratio for primary TAA failure in Cox regression analysis. The 10-year TAA survivorship rate was 91.1%. A younger age, chronic pulmonary disease, diabetes, and heavy alcohol consumption are risk factors for TAA.

Influence of Joint Line Level on Clinical Outcomes and Range of Motion in Total Ankle Arthroplasty.

Ankle arthritis leads to an elevated joint line compared to the nonarthritic ankle, as measured by the "joint line height ratio" (JLHR). Previous work has shown that the JLHR may remain elevated after total ankle arthroplasty (TAA). However, the clinical impact of this has yet to be determined. This study assessed the correlation between postoperative JLHR, post-TAA range of motion (ROM), and 1-year Patient-Reported Outcome Measurement Information System (PROMIS) scores. A retrospective review of 150 patients who underwent primary TAA was performed. Preoperative and postoperative JLHR, as well as postoperative dorsiflexion, plantarflexion, and total ROM, was calculated on weightbearing radiographs at a minimum of 1-year follow-up. Correlation between JLHR, post-TAA ROM, and 1-year PROMIS scores was investigated using Pearson correlation and multiple linear regression models. Interobserver reliability for the JLHR was also calculated. Interobserver reliability for the JLHR was excellent (r = 0.98). Mean (SD) JLHR changed from 1.66 (0.45) to 1.55 (0.26) after TAA (P < .001), indicating that the joint line was lowered after TAA. An elevated joint line was correlated with decreased post-TAA dorsiflexion (r = -0.26, P < .001), total ROM (r = -0.18, P = .025), and worse 1-year PROMIS physical function (r = -0.22, P = .046), pain intensity (r = 0.22, P = .042), and pain interference (r = 0.29, P = .007). There was no correlation between the JLHR and post-TAA plantarflexion (r = -0.025, P = .76). Regression analysis identified a 0.5-degree reduction in post-TAA dorsiflexion with each 0.1-unit increase in JLHR (Coeff. = -5.13, P = .005). In this patient cohort, we found that an elevated joint line modestly correlated with decreased postoperative dorsiflexion, total ROM, and worse 1-year PROMIS scores. These data suggest that effort likely should be made toward restoring the native joint line at the time of TAA. In addition, future studies investigating the clinical outcomes after TAA may consider including a measure of joint line height, such as the JLHR, because we found it was associated with patient-reported outcomes. Level III, retrospective review of prospectively collected data.

Comparison of Radiographic Talar Loosening Rates Between Salto-Talaris and INBONE II.

Despite substantial increase in total ankle arthroplasty (TAA) nationwide, there are few studies comparing flat-cut vs chamfer-cut talar systems in TAA with regard to radiographic aseptic loosening rates of the implant. This retrospective study included 189 Salto-Talaris TAA and 132 INBONE II primary TAA with a minimum 1-year follow-up. Patient characteristics were obtained including gender, age at surgery, body mass index (BMI), smoking status, primary diagnosis, surgical time, and the presence of diabetes. Radiographic evidence for aseptic loosening was assessed. Statistical analysis was performed for comparison in outcomes between Salto-Talaris and INBONE II. The mean age of the study population was 63.5 ± 9.8 years at surgery. Mean follow-up was 4.9 ± 3.0 years. Radiographic aseptic loosening of the tibial implant showed no significant difference between the 2 groups: Salto-Talaris, 18%, and INBONE II, 18.9% (P = .829). Aseptic loosening of the talar implant also showed no significant difference between the 2 groups: Salto-Talaris, 1.6%, and INBONE II, 1.5% (P = .959). No variables, including the implant type, were found to contribute to the aseptic loosening rate of either the tibia or talus. In our cohort, we observed no difference in radiographic implant aseptic loosening between Salto-Talaris and INBONE II systems. Level IV, retrospective case series study.

Younger Patients Undergoing Total Ankle Arthroplasty Experience Higher Complication Rates and Worse Functional Outcomes.

Although many patients with posttraumatic ankle arthritis are of a younger age, studies evaluating the impact of age on outcomes of primary total ankle arthroplasty (TAA) have revealed heterogenous results. The purpose of the present study was to determine the effect of age on complication rates and patient-reported outcomes after TAA. We retrospectively reviewed the records of 1,115 patients who had undergone primary TAA. The patients were divided into 3 age cohorts: <55 years (n = 196), 55 to 70 years (n = 657), and >70 years (n = 262). Demographic characteristics, intraoperative variables, postoperative complications, and patient-reported outcome measures were compared among groups with use of univariable analyses. Competing-risk regression analysis with adjustment for patient and implant characteristics was performed to assess the risk of implant failure by age group. The mean duration of follow-up was 5.6 years. Compared with the patients who were 55 to 70 years of age and >70 years of age, those who were <55 years of age had the highest rates of any reoperation (19.9%, 11.7%, and 6.5% for the <55, 55 to 70, and >70-year age groups, respectively; p < 0.001), implant failure (5.6%, 2.9%, and 1.1% for the <55, 55 to 70, and >70-year age groups, respectively; p = 0.019), and polyethylene exchange (7.7%, 4.3%, and 2.3% for the <55, 55 to 70, and >70-year age groups, respectively; p = 0.021). Competing-risk regression revealed a decreased risk of implant failure for patients who were >70 of age compared with those who were <55 years of age (hazard ratio [HR], 0.21 [95% confidence interval (CI), 0.05 to 0.80]; p = 0.023) and for patients who were 55 to 70 years of age compared with those who were <55 years of age (HR, 0.35 [95% CI, 0.16 to 0.77]; p = 0.009). For all subscales of the Foot and Ankle Outcome Score (FAOS) measure except activities of daily living, patients who were <55 years of age reported the lowest (worst) mean preoperative and postoperative scores compared with those who were 55 to 70 years of age and >70 years of age (p ≤ 0.001). Patients who were <55 years of age had the highest mean numerical pain score at the time of the latest follow-up (23.6, 14.4, 12.9 for the <55, 55 to 70, and >70-year age groups, respectively; p < 0.001). Studies involving large sample sizes with intermediate to long-term follow-up are critical to reveal age-related impacts on outcomes after TAA. In the present study, which we believe to be the largest single-institution series to date evaluating the effect of age on outcomes after TAA, younger patients had higher rates of complications and implant failure and fared worse on patient-reported outcome measures. Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Obesity and Ankle Prosthesis Revision: A Systematic Review and Meta-analysis.

The increasing number of total ankle arthroplasties (TAAs) has led to growing evidence on the risk factors for complications after surgery. However, the role of obesity in this patient group has been the subject of much debate. Therefore, this systematic review aimed to investigate the evidence for untoward effects of obesity following TAA. We conducted a comprehensive search on April 28, 2023, in MEDLINE (via PubMed), Embase, and CENTRAL. Eligible observational studies reported on the short- and long-term outcomes of primary TAA, comparing patients with and without obesity (defined as body mass index > 30). Using a random effects model, we calculated pooled odds ratios (ORs) with 95% confidence intervals (CIs) from 2 by 2 tables (event and nonevent in the obese and nonobese primary TAA groups). Nine studies with 10 388 patients were eligible for inclusion in the meta-analysis. We found significantly higher odds of revision in the obese group compared to the nonobese group (OR = 1.68, CI: 1.44-1.95). However, the odds of overall perioperative complications (OR = 1.55, CI: 0.50-4.80) and wound complications (OR = 1.34, CI: 0.29-6.20) were nonsignificantly higher in the obese group. Based on our results, obesity may have affected long-term outcomes following TAA and may have negatively affected the prosthesis's survival.

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.

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.

Long-Term Outcomes of Infinity Total Ankle Arthroplasty Compared to Ankle Arthrodesis

Category: Ankle Arthritis; Ankle Introduction/Purpose: End-stage ankle arthritis causes severe pain and disability. The most common treatment has been ankle arthrodesis (AA) with proven long-term results. However, total ankle arthroplasty (TAA) has become a viable option to preserve ankle joint motion, relieve pain and shield adjacent joints. And with the evolution of TAA prostheses over the past 2 decades, the use of TAA has been steadily increasing. Nevertheless, long term outcome data on the latest generation of TAA prostheses is scarce. The primary purpose of this study is to evaluate long-term PROMs after Infinity™ TAA and to compare the outcome to a patient cohort of ankle arthrodesis (AA) performed during the same time period. Methods: Patients with end-stage ankle arthritis who received surgical treatment with a primary Infinity TAA or AA performed between 2013-2015 were included in this study. All surgeries were performed by four fellowship trained foot and ankle surgeons. Patient reported outcomes (PROMs) comprising the AOS and SF-36 PCS score were prospectively collected for patients who were willing to enroll into the Canadian Orthopaedic Foot and Ankle Society (COFAS) database. PROM data was compared between the TAA and AA patient cohorts. Implant survivorship as well as revision and reoperation rates were also analyzed. Results: 33 patients/ankles underwent primary Infinity™ TAA and 59 patients/ankles underwent AA. Of these, 25 TAA and 46 AA were enrolled in the prospective database, 20 and 46 had PROMs available for follow-up, respectively. Mean TAA PROM follow- up was 6.8 years (3-9) and for AA 6.4 years (2-9). Mean TAA age at surgery was 67 years (54-85) and 58 years for AA (27-84). TAA total AOS score pre-operatively was 52.9, which improved significantly to 23.9. SF-36 PCS scores improved from 33.1 to 43.3. Pre- and post-operative PROMs were similar to the AA cohort. At clinical follow up of 8-10 years, TAA implant survival was 97% with one metal component exchange. Two TAA patients had two reoperations each. In the AA cohort, the reoperation rate was 10.8%. Conclusion: This is the first report on patient reported outcomes and implant survival at 8 or more years after primary Infinity™ TAA. PROMs remain significantly improved at long term follow-up and are comparable to a cohort of long-term AA patients. Revision rates were low with a single component revision in 33 patients resulting in an implant survivorship of 97%. Long-term outcome of the Infinity™ total ankle arthroplasty is promising.

Increased Hospital Length of Stay for Obesity Class II and III Patients After Primary Total Ankle Arthroplasty: A NSQIP Analysis

Category: Ankle Arthritis Introduction/Purpose: Obesity is a well-established risk factor for complications after total hip and knee arthroplasty. The incidence of total ankle arthroplasty (TAA) continues to grow, but few studies have evaluated TAA outcomes in patients with obesity. The present study sought to measure the impact of obesity on TAA outcomes using a national database. Methods: The 2012-2020 National Surgical Quality Improvement Program (NSQIP) database was queried for primary TAA (CPT:27002). 1,610 patients were identified and stratified by preoperative body mass index (BMI): non-obese (18 5-29.9kg/m2, n=760), obesity class I (30.0-34.9kg/m2, n=455), and class II and III (&gt;35.0kg/m2, n=395). Preoperative and perioperative patient data, operative time, hospital length of stay (LOS), and 30-day complications were compared using univariable statistics. Multivariable analyses controlling for patient characteristics were employed to measure the effect of obesity on operative time and LOS. Results: Compared to the non-obese group, obesity class II and III patients were younger (61.9 versus 65.6 years;p &lt; 0.001), more female (57.2% versus 42.0%;p &lt; 0.001), higher ASA class (p &lt; 0.001) and had more comorbidities such as hypertension, diabetes, and dyspnea (p &lt; 0.001). Mean preoperative albumin was lower (p=0.013) and white blood count was higher (p &lt; 0.001) in the obesity class II and III group. Home discharge rate was lowest in class II and III patients (88.6%;p=0.017). Multivariable regression revealed longer hospital LOS for obesity class II and III (μ=0.21; p=0.005) relative to the non-obese group. Obesity group was not associated with operative time or 30-day readmissions and reoperations. Conclusion: Obesity class II and III patients undergoing TAA had more comorbidities and longer hospital LOS compared to lower BMI patients. Despite the well-established association between obesity and postoperative complications after hip and knee arthroplasty, the present NSQIP analysis of 1,610 TAA patients did not find a greater burden of acute complications among patients with obesity.