Nationwide Analysis of Total Ankle Replacement and Ankle Arthrodesis in Medicare Patients: Trends, Complications, and Cost

Two-Year Outcomes After Total Ankle Replacement With a Novel Fixed-Bearing Implant By a Single Surgeon Non-Inventor

Total ankle arthroplasty continues to gain popularity amongst surgeons and patients as an alternative to arthrodesis. Historically the designs of early implants were plagued with complications and frequently abandoned. Since that time the procedure and materials have undergone significant advancements in both surgical approach as well as design and function of the available implants. In this study, 40 consecutive patients who received a semiconstrained prosthesis with a unique fixed-bearing polyethylene insert were identified. Minimum follow-up was 2 y. Demographic, social, and past medical data was retrospectively reviewed. Concomitant procedures were also recorded. Radiographic analysis included lateral ankle radiograph postoperative range of motion (ROM) with maximum dorsiflexion and maximum plantarflexion weight bearing at the most recent clinic visit. Clinical outcomes included VAS, FFI, and AOFAS scores. Lateral radiographs taken in the office at a minimum 2-y follow-up showed mean maximum dorsiflexion of 11.8 degrees and plantarflexion of 13.9 degrees. VAS, FFI, and AOFAS scores improved from 8.1, 92.9, and 44.8 to 1.4, 15.3, and 90.1 postoperatively, respectively. A total of 2.5% (n = 1) required revision surgery for poly failure, and 5.0% (n = 2) underwent local wound care in the office setting postoperatively and healed without complications. Overall survivorship was 97.5% at the minimum follow-up of 2 y. In conclusion, similar studies have reported survivorship from 90% to 100% with modern ankle implants in short to mid-term follow-up. Although this is a small sample size, our data shows a 97.5% survivorship at 2 y postoperatively with favorable patient-reported statistically significant functional outcome scores, and ankle range of motion consistent with existing literature.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

A predictive algorithm for perioperative complications and readmission after ankle arthrodesis

PURPOSE

Ankle arthrodesis is a mainstay of surgical management for ankle arthritis. Accurately risk-stratifying patients who undergo ankle arthrodesis would be of great utility. There is a paucity of accurate prediction models that can be used to pre-operatively risk-stratify patients for ankle arthrodesis. We aim to develop a predictive model for major perioperative complication or readmission after ankle arthrodesis.

METHODS

This is a retrospective cohort study of adult patients who underwent ankle arthrodesis at any non-federal California hospital between 2015 and 2017. The primary outcome is readmission within 30 days or major perioperative complication. We build logistic regression and ML models spanning different classes of modeling approaches, assessing discrimination and calibration. We also rank the contribution of the included variables to model performance for prediction of adverse outcomes.

RESULTS

A total of 1084 patients met inclusion criteria for this study. There were 131 patients with major complication or readmission (12.1%). The XGBoost algorithm demonstrates the highest discrimination with an area under the receiver operating characteristic curve of 0.707 and is well-calibrated. The features most important for prediction of adverse outcomes for the XGBoost model include: diabetes, peripheral vascular disease, teaching hospital status, morbid obesity, history of musculoskeletal infection, history of hip fracture, renal failure, implant complication, history of major fracture.

CONCLUSION

We report a well-calibrated algorithm for prediction of major perioperative complications and 30-day readmission after ankle arthrodesis. This tool may help accurately risk-stratify patients and decrease likelihood of major complications.

Clinical Outcomes and Registry Data in Total Ankle Arthroplasty

Total ankle arthroplasty (TAA) is an effective treatment for end-stage ankle arthritis consistently demonstrating good to excellent outcomes, even when considering factors such as deformity, patient age, bilaterality, and arthritis etiology. There is little consensus in the literature with regard to preferred patient-reported outcome metrics (PROMs) for assessing outcomes, although all metrics generally improve following TAA. Several countries have successful registries to track longevity of TAA in populations; however, PROMs are generally not successfully tracked in registries. A trend toward consensus on outcome metrics and collaborative registries is warranted to optimize patient selection and outcomes in TAA.

Partial revision of a dislocated periprosthetic tibial fracture after total ankle replacement with a stemmed implant and plate fixation: A case report

INTRODUCTION

Total ankle arthroplasty (TAR) procedures have become more reliable and incidence is increasing. A growing number of postoperative complications can be expected and should be correctly addressed.

PRESENTATION OF CASE

A 43-year-old woman suffering from severe ankle osteoarthritis underwent TAR (Stryker's Infinity with Prophecy alignment guides, uncemented tibial component and cemented talus component). After a fall, one month after the surgery, she presented with a fracture of the medial malleolus and an anterior periprosthetic fracture of the tibia, with anterior dislocation of the tibial prosthetic component. Fracture fixation and partial revision surgery was planned using the same anterior surgical access. To restore length, rotation and joint articulation, the medial malleolus was first reduced and synthesized with a plate and 6 screws through additional minimally invasive medial ankle incisions. Once the medial malleolus was stabilized, the already mobilized tibial component was removed. Freehand cuts under fluoroscopic guidance on the anterior surface of the tibia were performed. After a final check with a trial component, a Stryker's Inbone II stem, which matched the previously inserted talar component, was implanted and partially cemented to fill the remaining bone gaps.

DISCUSSION

Only few case reports of periprosthetic ankle fractures exist, and none of them were similar to ours. There are no published precedents for this revision approach from a stemless to a stemmed tibial implant without changing the talar implant.

CONCLUSION

Partial revision after a complex periprosthetic fracture results in a satisfactory outcome if surgery is performed in specialized centers.

Results of Total Ankle Arthroplasty Versus Ankle Arthrodesis

No differences have been found between total ankle arthroplasty (TAA) and ankle arthrodesis (AA) with respect to patient-reported outcome measures (PROMs), although both interventions were shown to improve PROMs with respect to the preoperative situation. That is, both interventions (AA and TAA) were effective in improving preoperative symptoms. On the other hand, 2-year complication rates were higher after AA (27%) than after TAA (16%); however, infection rates were similar (4%). The published revision rate after AA is 16% versus 11% after TAA. In short, TAA and AA appear to offer the same PROMs, but TAA has a lower rate of complications (except for infection) and revisions.

Effect of diabetes mellitus on the outcomes of total ankle arthroplasty: is controlled diabetes mellitus a risk factor?

BACKGROUND

It is still uncertain whether diabetes mellitus (DM) is a risk factor for poor outcomes and increased complications after total ankle arthroplasty (TAA). The objective of this study was to compare clinical outcomes and complication rates of TAA in patients with and without DM.

METHODS

This study enrolled patients with symptomatic end-stage ankle osteoarthritis with a minimum follow-up period of 24 months after TAA. A total of 252 patients (266 ankles) were classified into two groups according to the presence of DM: (1) DM group (59 patients, 67 ankles) and (2) non-DM group (193 patients, 199 ankles). We defined controlled diabetes as (1) HbA1c level < 7.0%, or (2) fasting glucose level < 130 mg/dL with HbA1c level ≥ 7.0% for hospitalization period. Clinical outcomes data (Ankle Osteoarthritis Scale, American Orthopedic Foot and Ankle Society ankle-hindfoot score, Short Form-36 Physical Component Summary score, and visual analog scale for pain) were compared preoperatively and at the final follow-up between the two groups. Complications following TAA were also compared between the two groups.

RESULTS

All clinical variables had improved in both groups by the final follow-up (mean follow-up = 77.8 months). There was no significant difference in any clinical variable between the two groups at the final follow-up (P > 0.05). Of the 266 ankles, 73 ankles (19 in the DM group, 54 in the non-DM group) developed periprosthetic osteolysis. Although the DM group showed a higher prevalence of aseptic loosening or subsidence, the difference between the two groups was not statistically significant (P = 0.236).

CONCLUSIONS

In the intermediate-term follow-up, TAA in patients with controlled DM showed clinical outcomes and complication rates comparable to patients without DM. Our results suggest that TAA can be done safely in diabetic patients if the DM is controlled in the perioperative period.

LEVEL OF EVIDENCE

Therapeutic Level III.

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.

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.

Complications Following Total Ankle Arthroplasty Versus Ankle Arthrodesis for Primary Ankle Osteoarthritis

INTRODUCTION

There are minimal data comparing complications between ankle arthrodesis (AA) versus total ankle arthroplasty (TAR) for operative management of primary osteoarthritis (OA). This study aimed to compare outcomes following AA versus TAR for primary ankle OA using a large patient database.

METHODS

Patients who received AA or TAR for primary ankle OA from 2010 to 2019 were queried from PearlDiver. Rates of common joint complications were compared at 90 days, 1 year, and 2 years postoperatively using multivariable logistic regression.

RESULTS

A total of 1136 (67%) patients received AA and 584 (33%) patients underwent TAR. Patients that received AA exhibited significantly higher rates of at least one common joint complication at 90 days (19.3% vs 12.6%; odds ratio [OR] 1.69), 1 year (25.6% vs 15.0%; OR 2.00), and 2 years (26.9% vs 16.2%; OR 1.91) postoperatively. This included higher rates of adjacent fusion or osteotomy procedures, periprosthetic fractures, and hardware removal at each postoperative follow-up (all P < .05). Rates of prosthetic joint infection were comparable at 2 years postoperatively (4.3% vs 4.2%; OR 0.91).

CONCLUSION

The AA cohort exhibited higher rates of postoperative joint complications in the short and medium-term, namely, subsequent fusions or osteotomies, periprosthetic fractures, and hardware removal.

LEVELS OF EVIDENCE

Level III.

Reoperation Rates Following Total Ankle Arthroplasty Versus Ankle Arthrodesis for Posttraumatic Indications

AIMS

This studied aimed to compare rates of reoperation for patients who received primary ankle arthrodesis (AA) versus total ankle replacement (TAR) for posttraumatic indications between 2010 and 2016 Q2 using a nationwide claims database.

METHODS

A retrospective cohort study analyzing patients who received primary AA or TAR for posttraumatic indications was performed using PearlDiver. Reoperations assessed included prosthetic joint infection (PJI), hardware removal, adjacent joint fusion, and local open reduction internal fixation (ORIF). Multivariable logistic regression was used to compare rates of reoperations at 1 and 2 years postdischarge.

RESULTS

A total of 862 (74%) patients received AA and 318 (26%) patients underwent TAR for a posttraumatic indication. At 1 year, 305 (35.4%) AA patients had at least 1 reoperation compared with 55 (17.3%) TAR patients (OR 2.32; 95% CI, 1.68-3.26). At 2 years, 364 (42.2%) AA patients and 66 (20.8%) TAR patients had at least 1 reoperation (OR 2.51; 95% CI, 1.84-3.45). ORIF, hardware removal, and adjacent joint fusions were more likely for AA patients at both time intervals (all Ps < .05).

CONCLUSION

Patients who received primary AA for posttraumatic indications exhibited higher rates of major reoperations in the short to medium term compared with patients who underwent TAR.

LEVELS OF EVIDENCE

Level III: Retrospective cohort study.

The Rise of Total Ankle Arthroplasty Use: A Database Analysis Describing Case Volumes and Incidence Trends in the United States Between 2009 and 2019

BACKGROUND

Ankle arthrodesis has been the mainstay treatment for end-stage ankle arthritis. The popularity of total ankle arthroplasty (TAA) has been on the rise due to improved implant design and postoperative outcomes. The purpose of this study was to describe the basic epidemiology and trends of annual procedure volumes and incidence in the general American population as well as in different population subgroups from 2009 to 2019. We hypothesize that the incidence of TAA has significantly risen while the median length of hospital stay has decreased nationwide.

METHODS

The IBM MarketScan database was queried for patients who underwent TAA from January 2009 to December 2019 based on Current Procedural Terminology coding. Population estimates from the US Census Bureau were used to calculate the annual incidence of TAA. Procedural volume and incidence were calculated for annual sums, gender, age subgroups, inpatient and outpatient TAA, as well as in four statistical geographic regions in the United States. Median length of hospital stay was calculated and trended annually for inpatient TAA.

RESULTS

A total of 41,060 primary TAAs were identified in the database from 2009 to 2019, in which 52.5% were performed in males. Annual volumes increased by 136.1%, from 2180 to 5147 procedures nationwide. Incidence reported per 100 000 population increased by 120.8%. Both inpatient and outpatient procedures have increased, by 242.5% and 86.6%, respectively. Median length of hospital stay decreased from 3 days in 2009 to 1 day in 2019 and did not differ between genders. Growth in incidence was demonstrated in males and females above the age of 54 years with the largest growth in annual incidence found between 65 and 74 years. Incidence rose in the South and West of the United States by 111.8% and 136.5%, respectively.

CONCLUSION

We found that annual volumes and incidence rates of primary TAA has increased between 2009 and 2019. Although both inpatient and outpatient surgery have become more frequent, inpatient volumes and incidence have increased almost 3 times more than those of outpatient surgery. Length of hospital stay decreased over the study years. When adjusted for the same study period, the cumulative annual growth rates of TAA were found to be 2 times greater than total knee arthroplasty and 3.6 times greater than total hip arthroplasty.

LEVEL OF EVIDENCE

Level III, retrospective database review.

Projections and Epidemiology of Total Ankle and Revision Total Ankle Arthroplasty in the United States to 2030

Background: Total ankle arthroplasty (TAA) utilization is increasing in the United States. As the incidence of this procedure grows, it is important for providers to understand the future projections for ankle arthroplasty and more importantly revision total ankle arthroplasty (rTAA). Methods: The National Inpatient Sample (USA) was queried from 2005 to 2017 for all TAA and rTAA. Poisson and linear regression analysis was performed to project annual incidence of TAA and rTAA to 2030, with subgroup analyses on septic rTAA. Results: There were 5315 TAAs performed in 2017, a 564% (P < .001) increase when compared with the TAAs performed in 2005. From 2017 to 2030, the incidence of TAAs is projected to increase from 110% to 796% (P < .001). There were 1170 rTAAs performed in 2017, a 155% (P < .001) increase when compared with rTAAs performed in 2005. There was a 256% increase in the incidence of septic rTAAs from 2005 to 2017 with a projected increase between 22% and 120% by 2030. Conclusions: The incidence of both TAAs and rTAAs is projected to significantly increase over the next decade. Given the known risk factors of TAA and rTAA, these findings reinforce the need for thoughtful consideration when selecting patients for TAA.

Trends and Reported Complications in Ankle Arthroplasty and Ankle Arthrodesis in the State of New York, 2009-2018

Background:

Ankle arthroplasty has emerged as a viable alternative to ankle arthrodesis due in large part to recent advancements in both surgical technique and implant design. This study seeks to document trends of arthroplasty and arthrodesis for ankle osteoarthritis in New York State from 2009-2018 in order to determine if patient demographics play a role in procedure selection and to ascertain the utilization of each procedure and rates of complications.

Methods:

Patients 40 years and older from 2009-2018 were identified using International Classification of Diseases, Ninth and Tenth Revisions (ICD-9 and ICD-10), Clinical Modification (CM) diagnosis and procedure codes for ankle osteoarthritis, ankle arthrodesis, and ankle arthroplasty in the New York statewide planning and research cooperative system database. A trend analysis for both inpatient and outpatient procedures was performed to evaluate the changing trends in utilization of ankle arthrodesis and ankle arthroplasty over time. A multivariable logistic regression was used to assess the odds of receiving ankle arthrodesis relative to ankle arthroplasty. Complications were compared between inpatient ankle arthrodesis and arthroplasty using multivariable Cox proportional hazards regression.

Results:

A total of 3735 cases were included. Ankle arthrodesis increased by 25%, whereas arthroplasty increased by 757%. African American race, federal insurance, workers compensation, presence of comorbidities, and higher social deprivation were associated with increased odds of having an ankle arthrodesis vs an ankle arthroplasty. Compared with ankle arthroplasty, ankle arthrodesis was associated with increased rates of readmission, surgical site infection, acute renal failure, cellulitis, urinary tract infection, and deep vein thrombosis.

Conclusion:

Ankle arthroplasty volume has grown substantially without a decrease in ankle arthrodesis volume, suggesting that ankle arthroplasty may be selectively used for a different population of patients than ankle arthrodesis patients. Despite the increased growth of ankle arthroplasty, certain patient demographics including patients from minority populations, federal insurance, and from areas of high social deprivation have higher odds of receiving arthrodesis.

Level of Evidence:

Level III, retrospective cohort.