Analysis of Total Ankle Arthroplasty Survival in the United States Using Multiple State Databases

The association of ASA score and outcomes following to.tal ankle arthroplasty

BACKGROUND

This study seeks to evaluate the relationship between American Society of Anesthesiologist (ASA) score and postoperative outcomes following TAA.

METHODS

The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database was queried from 2007 to 2020 to identify 2210 TAA patients. Patients were stratified into low (n = 1328; healthy/mild systemic disease) or high (n = 881; severe/life-threatening systemic disease) ASA score cohorts.

RESULTS

There was no statistically significant difference in complications, readmission, or reoperation rate based on ASA score. Increased ASA score was significantly associated with longer length of stay (low = 1.69 days, high = 1.98 days; p < .001) and higher rate of adverse discharge (low = 95.3 %, high = 87.4 %; p < .001).

CONCLUSION

Higher ASA scores (3 and 4) were statically significantly associated with increased length of stay and non-home discharge disposition. These findings are valuable for physicians and patients to consider prior to TAA given the increased utilization of resources and cost associated with higher ASA scores.

LEVEL OF EVIDENCE

Level III, Retrospective cohort study.

The Effect of Frontal Deformity at the Ankle Joint on Total Ankle Arthroplasty Revision Rate

The presence of severe coronal plane deformity in the ankle joint is widely recognized as challenging to correct by total ankle joint arthroplasty alone, necessitating additional rearfoot fusion. The primary aim of this retrospective study was to investigate the potential associations between the presence or severity of coronal tibiotalar deformities and adverse outcomes after isolated total ankle arthroplasty, such as revisions and complications. The secondary aim was to analyze the potential associations between comorbidities, demographics, and implant types, and adverse outcomes. Our study's distinctive feature was its exclusive concentration on patients with deformities centralized in the ankle joint. Chart review was performed on 496 ankles in 456 patients who had a total ankle arthroplasty by 5 surgeons from 1/1/2010 to 12/31/2019. After exclusion and inclusion criteria were applied, total of 214 ankles in 210 patients were included for data analysis. At a mean follow-up period of 3 ± 2.0 years, our cohort had 15 (7.0%) revisions and 15 (7.0%) complications. Multivariable logistic regression model showed that the presence or severity of the coronal deformity was not significantly associated with incidences of revisions or complications. Female patients had significantly lower revision rate. Otherwise, the differences in age, race, body mass index, tobacco use, presence of diabetes, chronic kidney disease, atrial fibrillation, length of surgery, or type of implant were not significantly associated with incidences of revisions or complications. Further study could be performed to analyze the extent and duration that the coronal deformity correction is maintained after total ankle arthroplasty as well as the effect of each soft tissue procedure performed with the total ankle arthroplasty.

Differential Utilization Patterns of Total Ankle Arthroplasty vs Arthrodesis: A United States National Ambulatory Database Analysis

Background

End-stage ankle osteoarthritis is a condition that can be treated with ankle arthrodesis (AA) or total ankle arthroplasty (TAA). The goal of this study is to estimate the 2016-2017 United States' utilization of TAA and AA in specific ambulatory settings and delineate patient and hospital factors associated with the selection of TAA vs AA for treatment of ankle osteoarthritis.

Methods

TAA and AA procedures performed for ankle osteoarthritis were identified in the 2016-2017 Nationwide Ambulatory Surgery Sample (NASS) Database. Notably, the NASS database only examines instances of ambulatory surgery encounters at hospital-owned facilities. As such, instances of TAA and AA performed at privately owned or freestanding ambulatory surgical centers or those performed inpatient are excluded from this analysis. Cases were weighted using nationally representative discharge weights. Univariate analyses and a combined multiple logistic regression model were used to compare demographic, hospital-related, and socioeconomic factors associated with TAA vs AA.

Results

In total, 6577 cases were identified, which represents 9072 cases after weighting. Of these, TAA was performed for 2233 (24.6%). Based on the logistic regression model, several factors were associated with increased utilization of TAA vs AA. With regard to patient factors, older patients were more likely to undergo TAA, as well as females. Conversely, patients with a higher comorbidity burden were less likely to receive TAA over AA.With regard to socioeconomic factors, urban teaching and urban nonteaching hospitals were significantly more likely to use TAA compared to rural hospitals. Similarly, privately insured patients and those with a median household income of $71 000 or more were also more likely to receive TAA over AA. Private hospitals ("not-for-profit" and "investor-owned") were significantly more likely to offer TAA over AA.

Conclusion

Using a large nationally representative cohort, the current data revealed that during 2016-2017, 24.6% of operatively treated cases of end-stage ankle osteoarthritis in the ambulatory setting are treated with TAA. Associations between socioeconomic and hospital-level factors with TAA utilization suggest that nonclinical factors may influence surgical treatment choice for ankle osteoarthritis.

Level of Evidence

Level III, retrospective cohort study.

The Burden of Revision Total Ankle Replacement Has Increased From 2010 to 2020

Background

Total ankle replacement (TAR) surgery has increased in recent decades. The aim of this study was to investigate the evolving burden of revision surgery and risk factors and timing of revision or explant.

Methods

Using the 2010 to 2020 PearlDiver M151Ortho data set, this retrospective cohort study identified primary TAR, TAR revision, and TAR explant patients via Current Procedural Terminology (CPT) and International Classification of Disease Procedural (ICD-P) codes. This database contains billing claims information across all payers and sites of care in the United States. Patient factors investigated included age, sex, and Elixhauser Comorbidity Index (ECI). Annual incidence for primary TAR was normalized per 100 000 covered lives in the data set for each year of study and recorded. Annual incidence of revision TAR and explant were normalized per 100 TARs performed for each year of study. Multivariate logistic regression analyses were performed to determine independent risk factors for revision TAR or explant. For explants, the eventual intervention by 2 years was analyzed. Ten-year timing and survival to revision or explant surgery following unilateral TAR were characterized.

Results

A total of 10 531 primary, 1218 revision, and 1735 explant TARs were identified. After normalization, TAR utilization increased by 284% from 2010 to 2020, annual TAR revisions rose 28%, and annual TAR explants decreased 65%. Independent predictors of revision TAR were younger age (odds ratio [OR] 1.29 per decade decrease) and higher ECI (OR 1.23 per 2-point increase). Independent predictors of explant included younger age (OR 1.80 per decade decrease), female sex (OR 1.17), and higher ECI (OR 1.35 per 2-point increase). The 10-year implant survival rate was 91.8%, of which 73% of revisions and 83% of explants occurred in the first 3 years following index TAR.

Conclusion

TAR utilization has grown substantially over the past decade, with minimal increases in the annual rate of revision surgery with respect to index procedures performed.

Level of Evidence

Level III, retrospective cohort study.

Five-Factor Modified Frailty Index as a Predictor of Complications Following Total Ankle Arthroplasty

INTRODUCTION

Ankle arthritis adversely affects patients' function and quality of life. Treatment options for end-stage ankle arthritis include total ankle arthroplasty (TAA). A 5-item modified frailty index (mFI-5) has predicted adverse outcomes following multiple orthopaedic procedures; this study evaluated its suitability as a risk-stratification tool in patients undergoing TAA.

METHODS

The National Surgical Quality Improvement Program (NSQIP) database was retrospectively reviewed for patients undergoing TAA between 2011 and 2017. Bivariate and multivariate statistical analyses were performed to investigate frailty as a possible predictor of postoperative complications.

RESULTS

In total, 1035 patients were identified. When comparing patients with an mFI-5 score of 0 versus ≥2, overall complication rates significantly increased from 5.24% to 19.38%, 30-day readmission rate increased from 0.24% to 3.1%, adverse discharge rate increased from 3.81% to 15.5%, and wound complications increased from 0.24% to 1.55%. After multivariate analysis, mFI-5 score remained significantly associated with patients' risk of developing any complication (P = .03) and 30-day readmission rate (P = .005).

CONCLUSIONS

Frailty is associated with adverse outcomes following TAA. The mFI-5 can help identify patients who are at an elevated risk of sustaining a complication, allowing for improved decision-making and perioperative care when considering TAA.

LEVELS OF EVIDENCE

III, Prognostic.

Analysis of Baseline Characteristics, Length of Stay, Cost of Care, Complications and Subgroup Analysis of Patients Undergoing Total Ankle Arthroplasty-A Large Database Study

Although total ankle arthroplasty (TAA) is becoming a progressively common procedure with a reported 10-fold increase in its prevalence over the past 2 decades; there is still limited large-scale data regarding its overall outcome. Using the National Inpatient Sample (NIS) database, patients who underwent TAA between 2016 and 2019 were identified (ICD-10 CMP code). Data regarding demographic details, co-morbidities, geographic locations of procedure, hospital stay, expenditure incurred, and complications encountered were analyzed. Additionally, a comprehensive subgroup analysis was performed to evaluate the impact of multiple preoperative variables (including gender, diabetes, obesity, CKD and tobacco abuse) on the patient outcome. Overall, 5087 patients (mean age: 65.1 years, 54% males, 85% Caucasians, 75% from large metropolitan regions) underwent TAA. Eighty eight percent of patients were discharged to home; and the mean length of hospital stay and hospital-related expenditure were 1.7 ± 1.41 days and $92,304.5 ± 50,794.1, respectively. The overall complication rate was 8.39% {commonest medical complications: anemia [131 (2.6%) patients) and acute renal failure [37 (0.7%) patients]; commonest local complication: periprosthetic mechanical adversities [90 (1.7%) patients]}. Female and CKD patients demonstrated significantly higher risks of medical (female: p = .003; CKD: p < .001) and surgical (female: p = .005; CKD: p < .019) complications; while obesity substantially enhanced the risk of medical adversities (p < .001). Based on our study, we could conclude that the rates of TAA in the United States are on the rise, especially in regions with population greater than 250,000. TAA is a safe procedure with relatively low complication rates. The complications and hospital-associated expenditure seem to vary between different patient subgroups.

Midterm Outcomes of the INBONETM II Total Ankle Arthroplasty

As the number of total ankle arthroplasties (TAA) performed continues to increase, understanding midterm outcomes can guide both implant selection and preoperative patient counseling. The purpose of this study was to investigate midterm results including the survival rate and reasons for revision for the INBONE^TM II TAA. Patients undergoing a primary TAA with the study implant and minimum of 4.6 years postoperative follow-up were reviewed from a prospectively collected database. The primary outcome was implant survival. Secondary outcomes included coronal plane radiographic alignment, evaluation for cysts and osteolysis, and failure mode when applicable. Patients were eligible for inclusion in this study if they had a minimum of 4.6-year follow-up TAA with the study implant. Eighty-five TAAs in 83 patients were eligible for inclusion; 75 TAA in 73 patients were included in the study. The mean duration of follow up was 6.2 ± 0.9 years (range 4.7-8.1 years). Thirty-six percent of the TAAs had a preoperative coronal plane deformity of at least 10^°, and 12% of the TAAs had at least 20^°. There were 6 (8%) implant failures that occurred at a mean 2.0 ± 1.4 years postoperatively. Eighty-one percent of the TAAs had no reoperation events in the follow-up period. Midterm outcomes at a minimum of 4.6 years postoperatively in patients undergoing a TAA using this implant demonstrates acceptable implant survival, an approximately 20% reoperation rate, and maintenance of coronal plane alignment.

Total Ankle Replacement Outcome in Patients With Inflammatory Versus Noninflammatory Arthritis: A Systematic Review and Meta-analysis

BACKGROUND

The decision regarding total ankle replacement (TAR) is challenging in patients with inflammatory arthritis (IA) regarding more inferior bone quality, large bone cysts, and increased risk of infections. This systematic review and meta-analysis aimed to compare the functional outcome, revision rate, complication rate, and survival rate of TAR between IA (including rheumatoid arthritis [RA]) and noninflammatory arthritis (NIA) (primary and posttraumatic).

METHODS

After reviewing the full texts, 30 articles fulfilled all inclusion criteria from 1985 until 2021, comparing TAR results. The eligible studies included 5508 patients, of whom 1565 patients had IA and 3943 patients had NIA. At the time of surgery, the average age was 58 years in the IA group and 63 in the NIA group. The average follow-up was 67.2 months in the IA group and 67 months in the NIA group. The outcome measures were the American Orthopaedic Foot and Ankle Society (AOFAS) score and the rate of complications, revisions, and survival.

RESULTS

The mean final AOFAS score was 82 (95% confidence interval [CI]: 78-86) in the IA group and 83 (95% CI: 78-88) in the NIA group, with no significant difference. There was no significant difference in the mean preoperative to postoperative AOFAS score change between the IA and the NIA. The complication rate was 16% (95% CI: 9%-27%) in the IA group and 15% (95% CI: 8%-27%) in the NIA group with no significant difference. The revision rate was 12% (95% CI: 10%-15%) in the IA group and 13% (95% CI: 10%-18%) in the NIA group, which was significant (P = .04). There was no significant difference in the survival rate between IA and NIA.

CONCLUSION

Total ankle replacement is a safe procedure in inflammatory ankle arthritis, specifically in RA patients with relatively minor and major complications close to other reasons for ankle replacement.

LEVELS OF EVIDENCE

Level IV: prognostic.

Factors Predictive of Early Complications Following Total Ankle Arthroplasty

Background:

The safety of outpatient total ankle arthroplasty (TAA), and factors predictive of early complications are poorly understood. The objective of this study was to determine the frequency of early complications in patients undergoing outpatient TAA compared to a matched inpatient TAA cohort. Factors predictive of early complications following TAA are elucidated.

Methods:

A retrospective review of prospectively collected data from the 2011-2018 American College of Surgeons–National Surgical Quality Improvement Program (ACS-NSQIP) database was performed. An unadjusted analysis comparing complication rates in outpatient, and inpatient TAA was performed followed by a propensity score–matched cohort analysis. A multivariate logistic regression model was then used to identify significant independent predictors for complications, reoperation, and readmission following TAA.

Results:

A total of 1487 patients (198 outpatient, 1289 inpatient) undergoing TAA were included in the study. Inpatient TAA was associated with increased 30-day readmission compared with outpatient TAA (3.54% vs 0.51%, P = .032) in a matched cohort analysis. Thirty-eight (2.6%) patients had a minor complication, with 16 (1.1%) patients having a major complication after TAR. Nineteen (1.3%) patients underwent reoperation, and 42 (2.8%) patients were readmitted within 30 days of the index TAR. Multivariate analysis identified factors predictive of early complications to include length of stay (LOS) >2 days, smoking, hypertension, bleeding disorders, and diabetes mellitus.

Conclusion:

From this relatively limited data set, outpatient TAA appears to be safe for management of end-stage ankle arthritis in select patients. Inpatient status was associated with an increased rate of 30-day readmission following TAA. Postoperative length of stay >2 days, smoking, hypertension, bleeding disorders, and diabetes mellitus were identified to be associated with early postoperative complications following TAA in this cohort.

Level of Evidence

Level III, retrospective cohort study.

Short-Term Complications Following Total Ankle Arthroplasty and Associated Risk Factors: A NSQIP Database Analysis

INTRODUCTION

Total ankle arthroplasty (TAA) has become increasingly utilized over the past 20 years to treat osteoarthritis of the ankle. The efficacy and safety of this procedure has been previously reported, but relatively few studies have documented the risk of postoperative complications associated with TAA over the past 10 years. Thus, the aim of this study is to provide a current report on the safety of TAA, particularly in association with a number of preoperative risk factors.

METHODS

A retrospective review of all patients in the American College of Surgeons National Surgical Quality Improvement Program database who underwent TAA between 2012 and 2018 was performed. A total of 1333 patients were included in this analysis. Penalized logistic regression to consider small numbers of the postoperative complications was used to identify factors associated with incidence of the complications.

RESULTS

The rate of readmission and superficial wound infection were found to be 1.4% and 0.6%, respectively. Risk factors associated with a prolonged hospital stay were black race, Hispanic race, and smoking. Diabetes was associated with a significantly increased risk of readmission. Age, sex, body mass index, and steroid use were not associated with increased risk of postoperative complications.

CONCLUSION

In this study, the rate of surgical site infection and readmission in TAA was found to be relatively low, compared to published data on total knee arthroplasty and total hip arthroplasty. Both race and smoking increase the risk of prolonged hospital stay, while diabetes increases the risk of readmission.

LEVELS OF EVIDENCE

Level III, retrospective comparative trial.

Revision Rates After Total Ankle Replacement: A Comparison of Clinical Studies and Arthroplasty Registers

BACKGROUND

The aim of this study was to assess the outcome of total ankle replacement (TAR) regarding revision rates by comparing clinical studies of the last decade to data displayed in arthroplasty registers. The secondary aim was to evaluate whether dependent clinical studies show a superior outcome to independent publications. Additionally, revision rates of mobile bearing implants (MB-TARs) were compared to those of fixed bearing implants (FB-TARs).

METHODS

Clinical studies on TARs between 2010 and 2020 were systematically reviewed, with the endpoint being a revision for any reason. The parameter "revision rate per 100 observed component years (CYs)" was calculated for each publication. The pooled revision rate for clinical studies was compared to the data reported in arthroplasty registers. In a second step, revision rates were subdivided and analyzed for independent and dependent publications and for FB-TARs and MB-TARs.

RESULTS

A total of 43 publications met the inclusion criteria comprising 5806 TARs. A revision rate of 1.8 per 100 observed CYs was calculated, corresponding to a 7-year revision rate of 12.6%. The 3 arthroplasty registers included showed revision rates ranging from 8.2% to 12.3% after 7 years. No significant difference between dependent and independent publications nor between FB-TARs and MB-TARs was detected.

CONCLUSION

Revision rates of clinical studies and arthroplasty registers are comparable. Surgeons can compare their own revision rates with those from this study. Dependent studies do not seem to be biased, and no superiority for one bearing type can be described.

LEVEL OF EVIDENCE

Level III, systematic review of level III studies.

Early Failure of Total Ankle Arthroplasty in a Patient with Ipsilateral Varus Knee Deformity

Multiple risk factors such as age, body mass index (BMI), preoperative diagnosis, smoking, diabetes mellitus, malalignment of an implant, and presence of ipsilateral hindfoot fusion have been shown to contribute to failure of total ankle arthroplasty (TAA). However, the exact causes of TAA failure remain uncertain, and various causes can lead to a need for revision surgery. We report a case of early aseptic loosening of the implant following TAA in a patient with severe varus deformity of the ipsilateral knee.

Establishing a New Patient-Specific Implantation Technique for Total Ankle Replacement: An In Vitro Study

BACKGROUND

Revision rates after total ankle replacements (TARs) are higher compared with other total joint replacements. The present study aimed to establish a new patient-specific implantation (PSI) technique for TAR.

MATERIAL AND METHODS

A total of 10 complete Caucasian cadaver legs had whole leg computed tomography scans. The individual geometrical ankle joint axis was determined, and based on this axis, the position of the prosthesis was planned. We assessed prosthesis placement, guiding block position, and preoperative and postoperative ankle rotational axes.

RESULTS

The guiding block position interobserver reliability was 0.37 mm 0.45 (mean ± SD) for the tibial guiding block. The value for the first talar guiding block was 1.72 ± 1.3 mm and for the second talar guiding block, 0.61 ± 0.39 mm. The tibial slope as well as the frontal angles of the anatomical tibial axis compared to the tibial and talar articular surfaces showed no statistically relevant differences with numbers available. The deviation of the assessed preoperative joint axis to the postoperative joint axis was 14.6° ± 7.8.

CONCLUSION

The present study describes the results of an establishing process of a new PSI technique for TAR. The reliability of guiding block positioning and, thereby, prosthesis placement is sufficient.

LEVEL OF EVIDENCE

Biomechanical study.

Incidence and Risk Factors for Flap Coverage After Total Ankle Arthroplasty

BACKGROUND

Wound complications following total ankle arthroplasty (TAA) can have a significant impact on patient morbidity, particularly when they require flap coverage. We sought to determine the risk factors associated with the need for flap coverage after TAA and hypothesized that medical and operative risk factors such as diabetes and additional procedures would be associated with the need for flap coverage after TAA.

METHODS

We performed a single-center retrospective review of TAAs from April 2007 to February 2019. Patient demographics and medical comorbidities were collected, in addition to other procedures performed at the time of TAA. Patients were stratified by the need for flap coverage, and unadjusted inferential statistics were performed to evaluate the risk factors associated with subsequent need for flap coverage.

RESULTS

Among 2065 patients undergoing TAA, 28 (1.4%) patients required flap coverage after the index arthroplasty. Patients requiring flap coverage were older (P = .045), had higher Charlson comorbidity indices (P = .017), and had higher rates of diabetes and pulmonary disease (P = .038). Patients requiring flap coverage also had higher rates of additional procedures (P = .043, P = .007). The most common flap was a radial forearm free flap, which was performed in 14 (50%) patients. Twenty-one patients (75%) requiring flap coverage had a stable, plantigrade foot at median 1.5-year follow-up.

CONCLUSION

Patient and operative risk factors, including advanced age, increased comorbidity burden, diabetes, pulmonary disease, and increased number of simultaneous procedures, were significantly associated with need for subsequent flap coverage. This should be considered as the indications for TAA expand.

LEVEL OF EVIDENCE

Level III, retrospective, prognostic cohort study.

Is load control necessary to produce physiological AP displacement and axial rotation in wear testing of TAR?

The International Standard Organization, ISO 22622, specifies two options for joint wear simulator evaluation of total ankle replacements (TARs): load-controlled and displacement-controlled. In the present study, the load-controlled testing parameters were applied to cadaveric specimens to quantify and compare the observed sagittal translations and axial rotations to those specified under the displacement-controlled option. Twelve cadaveric specimens were stripped of extraneous tissues, keeping surrounding ankle ligaments. A halo was used to produce plantarflexion and dorsiflexion of the talus through two screws, while a baseplate resisted axial loads. The axial force and torque were applied to the tibia and fibula under force and torque feedback control. An anterior-posterior force was applied to the tibia. Plantarflexion-dorsiflexion were applied using rotation control. To protect the cadaveric specimens, loads were applied at 50% of the specified load profile while plantarflexion-dorsiflexion rotation was applied as specified. There was variation among specimens in magnitudes of anterior-posterior displacement with peaks ranging from 3.3 mm posteriorly to 3.0 mm anteriorly. Likewise, there was variation among specimens in magnitude of axial rotation, with peaks ranging from 11° external rotation to 4.5° internal rotation. However, the mean magnitudes of AP displacement and axial rotation did not exceed those specified by ISO 22622.

Risk factors associated with failure of total ankle arthroplasty: a nationwide cohort study

We conducted a nationwide population-based cohort study to identify the risk factors associated with failure of total ankle arthroplasty (TAA). We included 2,914 subjects who underwent primary TAA between January 1, 2010, and December 31, 2016, utilizing the database of the Korean National Health Insurance Service. Failure of TAA was defined as revision TAA or arthrodesis procedures. An increased risk of TAA failure was observed in the < 65 age group versus the ≥ 75 age group [adjusted hazard ratios (aHR) 2.273, 95% confidence interval (CI) 1.223-4.226 in the 60-64 age group; aHR 2.697, 95% CI 1.405-5.178 in the 55-59 age group; aHR 2.281, 95% CI 1.145-4.543 in the 50-54 age group; aHR 2.851, 95% CI 1.311-6.203 in the < 50 age group]. Conversely, the ≥ 65 age group displayed no increase in the risk of TAA failure. The risk of TAA failure was increased in the severely obese group with body mass index (BMI) of ≥ 30 kg/m² versus the normal BMI group (aHR 1.632; 95% CI 1.036-2.570). This population-based longitudinal study demonstrated that age < 65 years and BMI of ≥ 30 kg/m² were associated with increased risk of TAA failure.

Analysis of early failure rate and its risk factor with 2157 total ankle replacements

The failure rate of TAA is still higher than that of other joint replacement procedures. This study aimed to calculate the early failure rate and identify associated patient factors. Data from the Korean Health Insurance Review and Assessment Service database from 2009 to 2017 were collected. We evaluated patients who had TAA as a primary surgical procedure. Early failure was defined as conversion to revision TAA or arthrodesis after primary TAA within five years. Patients with early failure after primary TAA were designated as the "Failure group". Patients without early failure and who were followed up unremarkably for at least five years after primary TAA were designated as the "No failure group". Overall, 2157 TAA participants were included. During the study period, 197 patients developed failure within five years postoperatively, for an overall failure rate of 9.1%. Significant risk factors for early failure were history of chronic pulmonary disease, diabetes, peripheral vascular disease, hyperlipidemia, dementia, and alcohol abuse. A significant increase of odds ratio was found in patients with a history of dementia, chronic pulmonary disease, and diabetes. Surgical indications and preoperative patient counseling should consider these factors.

Total Ankle Arthroplasty and Ankle Arthrodesis Use: An American Board of Orthopaedic Surgery Part II Database Study

Total ankle arthroplasty (TAA) use has increased during the past 20 years, whereas ankle arthrodesis (AAD) use has remained constant. The purpose of this study was to examine trends in TAA and AAD use in American Board of Orthopedic Surgery Part II candidates while considering the influence of fellowship training status on treatment of end-stage ankle arthritis. The American Board of Orthopedic Surgery Part II database was queried to identify all candidates who performed ≥1 TAA or AAD from examination years 2009 through 2018. Candidates were categorized by examination year and by self-reported fellowship training status. Descriptive statistical methods were used to report procedure volumes. Trends in use of TAA and AAD were examined by using log-modified regression analyses. From 2009through 2018, there was no significant change in TAA or AAD use among all candidates (p = .92, p = .20). Candidates reporting a foot and ankle fellowship trended toward increased use of TAA relative to AAD compared with non-foot and ankle fellowship candidates, but this failed to reach statistical significance (p = .06). The use of arthroscopic AAD increased over time (p < .01) among all candidates. TAA and AAD use did not change over the study period. Volume of TAA and AAD performed by early-career surgeons remains low. The findings in this study should serve as an important reference for orthopedic trainees, early-career surgeons, and orthopedic educators interested in optimizing training curriculum for surgical management of end-stage ankle arthritis.

Should 15° of valgus coronal-plane deformity be the upper limit for a total ankle arthroplasty?

AIMS

Preoperative talar valgus deformity ≥ 15° is considered a contraindication for total ankle arthroplasty (TAA). We compared operative procedures and clinical outcomes of TAA in patients with talar valgus deformity ≥ 15° and < 15°.

METHODS

A matched cohort of patients similar for demographics and components used but differing in preoperative coronal-plane tibiotalar valgus deformity ≥ 15° (valgus, n = 50; 52% male, mean age 65.8 years (SD 10.3), mean body mass index (BMI) 29.4 (SD 5.2)) or < 15° (control, n = 50; 58% male, mean age 65.6 years (SD 9.8), mean BMI 28.7 (SD 4.2)), underwent TAA by one surgeon. Preoperative and postoperative radiographs, Ankle Osteoarthritis Scale (AOS) pain and disability and 36-item Short Form Health Survey (SF-36) version 2 scores were collected prospectively. Ancillary procedures, secondary procedures, and complications were recorded.

RESULTS

At mean 5.1 years follow-up (SD 2.6) (valgus) and 6.6 years (SD 3.3) (controls), mean AOS scores decreased and SF-36 scores increased significantly in both groups. Improvements in scores were similar for both groups - AOS pain: valgus, mean 26.2 points (SD 24.2), controls, mean 22.3 points (SD 26.4); AOS disability: valgus, mean 41.2 points (SD 25.6); controls, mean 34.6 points (SD 24.3); and SF-36 PCS: valgus, mean 9.1 points (SD 14.1), controls, mean 7.4 points (SD 9.8). Valgus ankles underwent more ancillary procedures during TAA (40 (80%) vs 13 (26%)) and more secondary procedures postoperatively (18 (36%) vs 7 (14%)) than controls. Tibiotalar deformity improved significantly (p < 0.001) towards a normal weightbearing axis in valgus ankles. Three valgus and four control ankles required subsequent fusion, including two for deep infections (one in each group).

CONCLUSION

Satisfactory mid-term results were achieved in patients with preoperative valgus malalignment ≥ 15°, but they required more adjunctive procedures during and after TAA. Valgus coronal-plane deformity ≥ 15° is not an absolute contraindication for TAA if associated deformities are addressed. Cite this article: Bone Joint J 2020;102-B(12):1689-1696.

Patient Characteristics of Possible Responders and Nonresponders to Total Ankle Arthroplasty

BACKGROUND

Characteristics of responders, or those who achieve a clinical improvement above the level of a minimal clinically important difference, have not been defined for total ankle arthroplasty (TAA). The purpose of this study was to determine patient characteristics that distinguish possible responders from possible nonresponders after TAA using criteria established for other arthroplasty surgeries.

METHODS

Patients undergoing TAA who were enrolled into a prospective study at a single academic center evaluating patient-reported outcomes were included. Patients were characterized as possible responders if the relative or absolute improvement in their 2-year follow-up Short Musculoskeletal Function Assessment (SMFA) function score was at least 50% or 20, respectively, compared with their preoperative score, consistent with Outcome Measures in Rheumatoid Arthritis Clinical Trials and the Osteoarthritis Research Society International (OMERACT-OARSI) responder criteria. Patient factors were then associated with possible responder or nonresponder status and a multivariable analysis was performed. A total of 491 patients with complete data and 2-year follow-up were included in this study.

RESULTS

Multivariable analysis demonstrated that a higher baseline 36-Item Short-Form Survey (SF-36) mental component summary (MCS) score (OR [95% CI], 1.02 [1.01, 1.04]; P = .003), indicating better mental health, was associated with being a possible responder to TAA. The presence of rheumatic disease (OR [95% CI], 0.38 [0.22, 0.67]; P = .001) was a significant predictor of being a possible nonresponder.

CONCLUSION

Our data reveal that a higher baseline SF-36 MCS score was associated with increased improvement in SMFA function scores, while rheumatic disease was associated with worse improvement in SMFA function scores after TAA. Patients with rheumatic disease or poor mental health may not achieve as favorable results after TAA and should be counseled appropriately.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

The geometrical axis of the talocrural joint-Suggestions for a new measurement of the talocrural joint axis

BACKGROUND

Despite intensive research there is no consensus about the talocrural joint axis. The aim of the present study is a new method to determinate the geometric rotational axis of the talocrural joint.

METHODS

We analyzed 98 CT-scans of full cadaver Caucasian legs. We generated three-dimensional reconstruction models of the talus. A best fitting cone was orientated to the talar articular surface. The geometric rotational axis was defined to be the axis of this cone.

RESULTS

The geometric rotational axis of the talocrural joint is orientated from lateral-distal to medial-proximal (85.6°±10 compared to anatomical tibial axis in torsional plane), from posterior-distal to anterior-proximal (81.43°±44.35 compared to anatomical tibial axis in sagittal plane) and from posterior-medial to anterior-lateral (169.2°±5.91 compared to intermalleolar axis in axial plane).

CONCLUSIONS

The consideration of our results might be helpful for better understanding of ankle biomechanics.

Association of Peripheral Vascular Disease With Complications After Total Ankle Arthroplasty

Background:

Despite limited evidence, peripheral vascular disease is often cited as a contraindication for total ankle arthroplasty. The purpose of our study was to identify whether peripheral vascular disease in patients undergoing total ankle arthroplasty increased the rate of infection, postoperative irrigation and debridement, or failure of the implant.

Methods:

The PearlDiver Database was used to identify Medicare patients who underwent a total ankle arthroplasty from 2005 to 2014. These data were then analyzed for postoperative infections within 90 days, subsequent irrigation and debridements, and failure of total ankle arthroplasties. A diagnosis of preoperative peripheral vascular disease only included those patients who had peripheral vascular disease as an ICD-9 diagnosis code and underwent a preoperative lower extremity angiogram prior to total ankle arthroplasty. Medical comorbidities were identified using ICD-9 diagnosis codes. Three multivariable logistic regression models were then developed in order to identify risk factors associated with postoperative infections and failure after total ankle arthroplasty.

Results:

A total of 10 698 Medicare patients who underwent a primary total ankle arthroplasty were identified. There were 334 patients who had a postoperative infection within 90 days of their total ankle arthroplasty, and 95 of those patients required an irrigation and debridement. Regression analysis demonstrated that patients with peripheral vascular disease had the greatest risk of developing a postoperative infection within 90 days (OR 2.85, P < .01), requiring an irrigation and debridement postoperatively (OR 4.87, P < .001), and having a total ankle arthroplasty failure at any time point postoperatively (OR 2.51, P < .001).

Conclusions:

Our study suggests that preoperative peripheral vascular disease is a significant risk factor for an acute postoperative infection, postoperative irrigation and debridement, and failure of the implant in Medicare patients undergoing a total ankle arthroplasty.

Level of Evidence:

Level III, therapeutic.

Risk Factors for Failure of Total Ankle Arthroplasty With a Minimum Five Years of Follow-up

BACKGROUND:

As the popularity of total ankle arthroplasty (TAA) increases and indications expand, surgeons require a better understanding of which patient factors are associated with implant failure. In this study, we aimed to use a large total ankle database to identify independent risk factors for implant failure at mid- to long-term follow-up.

METHODS:

A prospectively collected database was used to identify all patients who underwent primary TAA with a minimum 5 years' follow-up. The primary outcome was revision, defined as removal of one or both metal components; failures due to infection were excluded. Patient and clinical factors analyzed included age, sex, body mass index (BMI), smoking status, presence of diabetes, indication for TAA, implant, tourniquet time, and presence of ipsilateral hindfoot fusion. Preoperative coronal deformity and sagittal talar translation were assessed, as were postoperative coronal and sagittal tibial component alignment. Univariable and multivariable analyses were performed to identify predictors of implant failure. After excluding 5 ankles that failed because of deep infection, 533 ankles with a mean 7 (range, 5-11) years of follow-up met the inclusion criteria. Four implants were used: INBONE I, INBONE II, STAR, and Salto-Talaris.

RESULTS:

Thirty-four ankles (6.4%) were revised or removed a mean 4 (range, 1-9) years postoperatively. The only independent predictors of failure were the INBONE I prosthesis and ipsilateral hindfoot fusion ( P = .006 and P = .023, respectively).

CONCLUSIONS:

This is among the largest studies to analyze the relationship between TAA failure rates and multiple different patient, operative, and radiographic factors. Of note, age, BMI, and amount of deformity were not associated with higher failure rates. Only patients with ipsilateral hindfoot fusion or who received the INBONE I prosthesis were at significantly higher risk of implant failure.

LEVEL OF EVIDENCE:

Level III, retrospective cohort study.

The Effect of Patient Characteristics on 1 to 2-Year and Minimum 5-Year Outcomes After Total Ankle Arthroplasty

BACKGROUND

Total ankle arthroplasty has shown durable improvements in patient-reported outcomes. However, the impact of common comorbidities and patient factors has not been fully characterized. The purpose of this study was to identify patient comorbidities and characteristics that impact outcomes after total ankle arthroplasty.

METHODS

Patients who underwent a total ankle arthroplasty between January 2007 and December 2016 were enrolled into a prospective study at a single academic center. Patients completed outcome measures before the surgical procedure and at the time of follow-up: a visual analog scale (VAS) for pain, the 36-item Short Form Survey (SF-36), and the Short Musculoskeletal Function Assessment (SMFA). Patient and operative factors, along with prevalent preoperative comorbidities, were analyzed for association with preoperative to postoperative changes in 1 to 2-year and minimum 5-year outcomes. Comorbidities that met a significance threshold of p < 0.05 in adjusted analyses were incorporated into multivariable outcome models.

RESULTS

A total of 668 patients with a mean 1 to 2-year follow-up (and standard deviation) of 1.6 ± 0.5 years (range, 10 months to 2 years and 2 months) were included. Patients' pain and function significantly improved across all outcomes (p < 0.05). However, depression, staged bilateral ankle arthroplasty, increased length of stay, a prior surgical procedure, increased American Society of Anesthesiologists (ASA) score, and particular implant types were associated with significantly smaller improvements in at least 1 patient-reported outcome after total ankle arthroplasty in the 1 to 2-year follow-up, although the effects were relatively small. At a minimum 5-year follow-up, smoking, depression, implant type, and staged bilateral ankle arthroplasty were associated with worse outcomes, and a prior surgical procedure, a simultaneous bilateral surgical procedure, and obesity were associated with improved outcomes.

CONCLUSIONS

Patients who underwent total ankle arthroplasty had significant improvement in patient-reported outcomes, although several factors were associated with a small, but significant, negative impact on improvement, including depression, increased ASA score, current smoking, increased length of stay, a prior surgical procedure, and staged bilateral total ankle arthroplasty. Current smoking, obesity, and depression are potentially modifiable risk factors that could be improved prior to total ankle arthroplasty. Patients with these characteristics should be counseled on their risk of limited improvement in ankle pain and disability after total ankle arthroplasty.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Possible Implications for Bundled Payment Models of Comorbidities and Complications as Drivers of Cost in Total Ankle Arthroplasty

BACKGROUND:

The Comprehensive Care for Joint Replacement (CJR) model provides bundled payments for in-hospital and 90-day postdischarge care of patients undergoing total ankle arthroplasty (TAA). Defining patient factors associated with increased costs during TAA could help identify modifiable preoperative patient factors that could be addressed prior to the patient entering the bundle, as well as determine targets for cost reduction in postoperative care.

METHODS:

This study is part of an institutional review board-approved single-center observational study of patients undergoing TAA from January 1, 2012, to December 15, 2016. Patients were included if they met CJR criteria for inclusion into the bundled payment model. All Medicare payments beginning at the index procedure through 90 days postoperatively were identified. Patient, operative, and postoperative characteristics were associated with costs in adjusted, multivariable analyses. One hundred thirty-seven patients met inclusion criteria for the study.

RESULTS:

Cerebrovascular disease (intracranial hemorrhages, strokes, or transient ischemic attacks) was initially associated with increased costs (mean, $5595.25; 95% CI, $1710.22-$9480.28) in adjusted analyses ( P = .005), though this variable did not meet a significance threshold adjusted for multiple comparisons. Increased length of stay, discharge to a skilled nursing facility (SNF), admissions, emergency department (ED) visits, and wound complications were significant postoperative drivers of payment.

CONCLUSION:

Common comorbidities did not reliably predict increased costs. Increased length of stay, discharge to an SNF, readmission, ED visits, and wound complications were postoperative factors that considerably increased costs. Lastly, reducing the rates of SNF placement, readmission, ED visitation, and wound complications are targets for reducing costs for patients undergoing TAA.

LEVEL OF EVIDENCE:

Level II, prognostic prospective cohort study.

Management of Posttraumatic Ankle Arthritis: Literature Review

PURPOSE OF REVIEW

Trauma is the principle cause of osteoarthritis in the ankle, which is associated with significant morbidity. This review highlights the current literature for the purpose of bringing the reader up-to-date on the management of posttraumatic ankle arthritis, describing treatment efficacy, indications, contraindications, and complications.

RECENT FINDINGS

Recent studies on osteoarthritis have demonstrated variability among anatomic locations regarding the mechanisms and rates of development for posttraumatic osteoarthritis, which are attributed to newly discovered biological differences intrinsic to each joint. Regarding surgical management of posttraumatic ankle arthritis, osteochondral allograft transplantation of the talus, and supramalleolar osteotomies have demonstrated promising results. Additionally, the outpatient setting was found to be appropriate for managing pain following total ankle arthroplasty, associated with low complication rates and no readmission. Management for posttraumatic ankle arthritis is generally progressive. Initial treatment entails nonpharmacologic options with surgery reserved for posttraumatic ankle arthritis refractory to conservative treatment. Patient demographics and lifestyles should be carefully considered when formulating a management strategy, as outcomes are dependent upon the satisfaction of each set of respective criteria. Ultimately, the management of posttraumatic ankle arthritis should be individualized to satisfy the needs and desires, which are specific to each patient.

Patient-Related Risk Factors for Periprosthetic Ankle Joint Infection: An Analysis of 6977 Total Ankle Arthroplasties

Periprosthetic joint infection (PJI) after total ankle arthroplasty (TAA) is a devastating complication that often results in explantation to resolve the infection. The purpose of the present investigation was to determine the patient-related risk factors for PJI after TAA. A national insurance database was queried for patients undergoing TAA using the Current Procedural Terminology and International Classification of Diseases, ninth revision, procedure codes from 2005 to 2012. Patients undergoing TAA with concomitant fusion procedures or more complex forefoot procedures were excluded. PJI within 6 months was then assessed using the International Classification of Diseases, ninth revision, codes for diagnosis or treatment of postoperative PJI. Multivariate binomial logistic regression analysis was performed to evaluate the patient-related risk factors for PJI. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each risk factor, with p < .05 considered statistically significant. A total of 6977 patients were included in the present study. Of these 6977 patients, 294 (4%) had a diagnosis of, or had undergone a procedure for, PJI. The independent risk factors for PJI included age <65 years (OR 1.44; p = .036), body mass index <19 kg/m² (OR 3.35; p = .013), body mass index >30 kg/m² (OR 1.49; p = .034), tobacco use (OR 1.59; p = .002), diabetes mellitus (OR 1.36; p = .017), inflammatory arthritis (OR 2.38; p < .0001), peripheral vascular disease (OR 1.64; p < .0001), chronic lung disease (OR 1.37; p = .022), and hypothyroidism (OR 1.32; p = .022). The independent patient-related risk factors identified in the present study should help guide physicians and patients considering elective TAA and develop risk stratification algorithms that could decrease the risk of deep, postoperative infection.

Patient Risk Factors Do Not Impact 90-Day Readmission and Emergency Department Visitation After Total Ankle Arthroplasty: Implications for the Comprehensive Care for Joint Replacement (CJR) Bundled Payment Plan

BACKGROUND

The Comprehensive Care for Joint Replacement (CJR) model provides bundled payments for in-hospital care and care within 90 days following discharge for Medicare beneficiaries undergoing lower-extremity joint replacement involving the hip, knee, or ankle (total hip arthroplasty, total knee arthroplasty, or total ankle arthroplasty [TAA]). The study hypothesis was that patient comorbidities are associated with readmissions, emergency department (ED) utilization, and subspecialist wound-healing consultation, which are examples of costly contributors to postoperative health-care spending.

METHODS

The medical records for 1,024 patients undergoing TAAs between June 2007 and December 2016 at a single academic center in the southeastern United States were reviewed for the outcomes of readmissions, ED visitations, and subspecialist wound-healing consultation within the 90-day post-discharge period. All patients undergoing TAA (n = 1,365) were eligible. Of the 1,037 patients who consented to participation in the study and underwent TAA, 1,024 (98.7%) completed the study. Medical comorbidities according to the Elixhauser and Charlson-Deyo comorbidity indices that were present prior to TAA were recorded. Univariate and multivariable tests of significance were used to relate patient and operative characteristics to outcomes.

RESULTS

Four hundred and ninety-six (48.4%) of the 1,024 patients were female, and 964 (94.1%) were white/Caucasian, with an average age (and standard deviation) of 63 ± 10.5 years. Hypertension, obesity, solid tumor, depression, rheumatic disease, cardiac arrhythmia, hypothyroidism, diabetes mellitus, and chronic pulmonary disease had a prevalence of >10%. Fifty-three (5.2%) of the 1,024 patients were readmitted for any cause. Thirty-six (3.5%) of the 1,024 returned to the ED but were not admitted to the hospital. Readmission or ED visitation was most commonly for a wound complication, followed by deep venous thrombosis (DVT) and pulmonary embolism (PE) evaluation, while urgent medical evaluations composed the majority of non-TAA-related ED visitations. No patient comorbidities were significantly associated with 90-day readmission, ED visitation, or wound complications in multivariable models.

CONCLUSIONS

Patient comorbidities were not associated with 90-day hospital readmissions or ED visitation for patients undergoing TAA. Readmissions were dominated by evaluation of wound compromise as well as DVT and PE. These data suggest that there may be considerable differences between TAA and total hip arthroplasty or total knee arthroplasty that cause surgeons to question the inclusion of TAA in CJR bundled payment models.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Establishing benchmarks for the volume-outcome relationship for common lumbar spine surgical procedures

BACKGROUND CONTEXT

The importance of surgeon volume as a quality measure has been defined for a number of surgical specialties. Meaningful procedural volume benchmarks have not been established, however, particularly with respect to lumbar spine surgery.

PURPOSE

We aimed to establish surgeon volume benchmarks for the performance of four common lumbar spine surgical procedures (discectomy, decompression, lumbar interbody fusion, and lumbar posterolateral fusion).

STUDY DESIGN

A retrospective review of data in the Florida Statewide Inpatient Dataset (2011-2014) was carried out.

PATIENT SAMPLE

Patients who underwent one of the four lumbar spine surgical procedures under study comprised the study sample.

OUTCOME MEASURE

The development of a complication or hospital readmission within 90 days of the surgical procedure was the surgical outcome.

METHODS

For each specific procedure, individual surgeon volume was separately plotted against the number of complications and readmissions in a spline analysis that adjusted for co-variates. Spline cut-points were used to create a categorical variable of procedure volume for each individual procedure. Log-binomial regression analysis was then separately performed using the categorical volume-outcome metric for each individual procedure and for the outcomes of 90-day complications and 90-day readmissions.

RESULTS

In all, 187,185 spine surgical procedures met inclusion criteria, performed by 5,514 different surgeons at 178 hospitals. Spline analysis determined that the procedure volume cut-point was 25 for decompressions, 40 for discectomy, 43 for interbody fusion, and 35 for posterolateral fusions. For surgeons who failed to meet the volume metric, there was a 63% increase in the risk of complications following decompressions, a 56% increase in the risk of complications following discectomy, a 15% increase in the risk of complications following lumbar interbody fusions, and a 47% increase in the risk of complications following posterolateral fusions. Findings were similar for readmission measures.

CONCLUSIONS

The results of this work allow us to identify meaningful volume-based benchmarks for the performance of common lumbar spine surgical procedures including decompression, discectomy, and fusion-based procedures. Based on our determinations, readily achievable goals for individual surgeons would approximate an average of four discectomy and lumbar interbody fusion procedures per month, three posterolateral lumbar fusions per month, and at least one decompression surgery every other week.

Midterm Outcomes of a Fixed-Bearing Total Ankle Arthroplasty With Deformity Analysis

BACKGROUND

We present our results with an INBONE I (Wright Medical, Memphis, TN) prosthesis that have a minimum of 4 to 10 years of follow-up and include a preoperative deformity analysis on outcomes.

METHODS

A consecutive series of 149 patients, from 2007 to 2011, at a single institution were enrolled. Pain and patient-reported function were assessed preoperatively and at yearly follow-ups. We analyzed the data for complications, reoperations, and failures (defined as undergoing revision for exchange or removal of one or both metallic components for any reason). Patients were also grouped according to coronal plane tibiotalar alignment; either ≥10 degrees or <10 degrees, and these outcomes were compared. Our follow-up ranged from 48 to 113 months (average 5.9 years).

RESULTS

There was significant improvement ( P < .05) in the visual analog scale for pain, American Orthopaedic Foot & Ankle Society hindfoot scale, Short Musculoskeletal Function Assessment, and Short Form 36-Item Health Survey scores at most recent follow-up. There were 14 implant failures with overall survivorship of 90.6% (135/149). Reasons for failure included cysts/loosening (7), talar subsidence (4), fractured component (1), impingement pain (1), and infection (1). Seventy-two patients (48.3%) with preoperative coronal plane deformity of ≥10 degrees varus or valgus were compared to 78 patients (51.7%) with <10 degrees deformity. There was no difference in patient outcome scores or revision rates between these patient groups. There was a statistically significant difference ( P = .039) in reoperation rates among patients with ≥10 degrees deformity (22.2%) compared to those without such a deformity (37.7%) Conclusion: Patients who underwent INBONE I fixed-bearing total ankle arthroplasty demonstrated significant improvement in outcomes at a mean of 5.9 years. Catastrophic talar component collapse did occur (2.7% of cases), but relatively rarely. The patients with preoperative coronal plane tibiotalar deformity had similar pain relief, function, and need for revision of implant components. Despite the presumed shortcomings of the INBONE I's design, this implant showed promising results, with or without deformity, at midterm follow-up with survivorship of 90.6%.

LEVEL OF EVIDENCE

Level III, comparative study.

Ankle Arthrodesis Versus Total Ankle Arthroplasty

Reoperation rates are higher in total ankle arthroplasties (TAAs) compared with ankle arthrodesis. Infection rates for primary TAAs are 1.4% to 2.4%. The survival rate of TAA is approximately 75% to 90% at 10 years. Arc of motion is maintained with TAAs compared with ankle arthrodesis. Ankle arthrodesis increases arc of motion through the talonavicular joint. Several factors are strong reasons to favor ankle fusion rather than TAA. TAA and ankle arthrodesis are effective treatments of end-stage ankle arthritis but the choice must be tailored to individual patients.