Trends in the Utilization of Ankle Replacements: Data From Worldwide National Joint Registries

Median age of patients undergoing total ankle replacement has not significantly changed between 1999 and 2023: A systematic review of prospective studies

INTRODUCTION

Total ankle replacement (TAR) is an effective treatment for end-stage osteoarthritis. The aim of this systematic review was to assess the age of patients undergoing TAR in prospective comparative studies. Our hypothesis is that the age reported in most recent papers might be lower than those reported in older papers.

METHODS

This systematic review was performed using Pubmed, Scopus, EMBASE and Cochrane databases. Only Level I and II studies dealing with TAR were included. Data regarding demographics, study design, number of cohorts in each study, year of publication and year/years in which surgery was performed were extracted. A two-fold analysis was conducted building groups of patients based on the year of publication and creating 1) two groups (before and after the median year) and 2) three groups (using tertiles) in order to compare age of patients operated in different period of times. A comparison was also performed considering the median year of surgery for patients undergoing TAR.

RESULTS

Overall 59 cohorts (42 studies, published between 1999 and 2023; median year of publication: 2017) were included (6397 ankles, 6317 patients, median age 63 years). The difference between the median age for 27 cohorts published until 2016 (weighted median 63 years; IQR, 62.5-64) and the median age for 32 cohorts published after 2017 (weighted median 63.2 years; IQR, 63-67.8) was not statistically significant (p = 0.09). The division in tertiles did not reveal any significant change in the weighted median age at surgery (T1 (1999-2014; 63.2 years; IQR, 62.8-64.1), T2 (2015-2018; 63 years; IQR,63-63.5) and T3 (2019-2023; 63.2 years; IQR, 62.6-67.8)) over time (p = 0.65). The median age of patients operated between 1999 and 2008 vs 2009 and 2023 (data from 48 cohorts) was not different either (p = 0.12).

CONCLUSION

According to this review of prospective studies published between 1999 and 2023, the median age for patients undergoing TAR over the last two decades has been 63 years, remaining steady with no significant changes over time.

LEVEL OF EVIDENCE

Level II - systematic review including Level I and Level II studies.

Custom Patient-Specific 3D-Printed Titanium Truss Tibiotalocalcaneal Arthrodesis Implants for Failed Total Ankle Replacements: Classification, Technical Tips, and Treatment Algorithm

BACKGROUND

The management of failed total ankle replacements, with significant loss of bone stock, is challenging with high rates of complications and associated morbidity. Recent technological advances have enabled the development of patient-customized 3D-printed titanium truss arthrodesis implants, which offer an alternative salvage option for failed total ankle replacements.

METHODS

A prospective observational study was performed of 6 cases of failed total ankle replacements that were managed using custom patient-specific 3D-printed titanium truss arthrodesis implants. Technical tips, classification, and a treatment algorithm were developed based on our initial experience.

RESULTS

Between November 2018 and March 2022, 6 patients underwent arthrodesis for failed total ankle replacements. Follow-up was available for all cases. The mean follow-up was 3.0 years (range 1-4.5). The mean MOXFQ Index improved from 73.1 to 32.3 (P < .05). The mean EQ-5D-5L Index improved from 0.366 to 0.743 (P < .05) and the EQ-VAS also improved from 53.0 to 63.3 (P = .36). The mean VAS-Pain score at final follow-up was 27.5. There were no cases of nonunion. None of the patients were smokers. The overall complication rate was 50%. Two patients returned to surgery: one for wound washout following TAR explantation and a second for removal of metalwork 2 years following surgery for a prosthetic joint infection secondary to hematogenous spread. No patients underwent revision fixation or amputation.

CONCLUSION

Custom patient-specific 3D-printed titanium truss arthrodesis implants are a viable treatment option for failed total ankle replacements.

Current Trends in Total Ankle Replacement

Ankle arthritis can result in significant pain and restriction in range of motion. Total ankle replacement (TAR) is a motion-preserving surgical option used as an alternative to total ankle arthrodesis to treat end-stage ankle arthritis. There are several generations of TAR techniques based on component design, implant material, and surgical technique. With more recent TAR implants, an attempt is made to minimize bone resection and mirror the native anatomy. There are more than 20 implant devices currently available. Implant survivorship varies among prosthesis types and generations, with improved outcomes reported with use of the more recent third- and fourth-generation ankle implants. Pre- and postoperative assessments of TAR are primarily performed by using weight-bearing radiography, with weight-bearing CT emerging as an additional imaging tool. Preoperative assessments include those of the tibiotalar angle, offset, and adjacent areas of arthritis requiring additional surgical procedures. US, nuclear medicine studies, and MRI can be used to troubleshoot complications. Effective radiologic assessment requires an understanding of the component design and corresponding normal perioperative imaging features of ankle implants, as well as recognition of common and device-specific complications. General complications seen at radiography include aseptic loosening, osteolysis, hardware subsidence, periprosthetic fracture, infection, gutter impingement, heterotopic ossification, and syndesmotic nonunion. The authors review several recent generations of TAR implants commonly used in the United States, normal pre- and postoperative imaging assessment, and imaging complications of TAR. Indications for advanced imaging of TAR are also reviewed. ©RSNA, 2023 Supplemental material is available for this article. Test Your Knowledge questions for this article are available through the Online Learning Center.

Outcomes of total ankle replacement - Current evidence

Total ankle replacement surgery is gaining popularity and is beginning to establish itself as a viable alternative to arthrodesis in the treatment of end-stage ankle arthritis. Only a few studies exist directly comparing these 2 techniques. Also lacking are the long-term outcome studies of ankle replacement surgery. A better understanding of clinical and patient-reported outcome measures after ankle fusion and replacement will enable the surgeon to better counsel the patient and help choose the right treatment. This article will summarise the reported clinical outcomes after total ankle replacements and survivorship analysis from the various national arthroplasty registers.

Total ankle replacement versus ankle fusion for end-stage ankle arthritis: A meta-analysis

PURPOSE

This study aims to systematically review the efficacy and safety of total ankle replacement (TAR) and ankle fusion (AF) as treatment options for end-stage ankle arthritis.

METHODS

A comprehensive literature search was conducted on data from multiple databases, including PubMed, The Cochrane Library, Construction and Building Materials, Embase, Web of Science, and Scopus for RCTs and prospective cohort studies comparing TAR and AF in patients with end-stage ankle arthritis from inception up to June, 2023. Our primary outcomes of interest included patients' clinical function scores and complications. We employed Review Manager 5.4 and Stata/MP 14.0 software for the meta-analysis.

RESULTS

Our analysis incorporated 13 comparative studies, including 11 prospective studies, one pilot RCT, and one RCT. The pooled results revealed no significant difference in postoperative Short Form-36 scores between the TAR and AF groups (MD = -1.19, 95% CI: -3.89 to 1.50, p = .39). However, the postoperative Foot and Ankle Ability Measure scores in the AF group were significantly higher than in the TAR group (MD = 8.30, 95% CI: 1.01-15.60, p = .03). There was no significant difference in postoperative complication rates between the TAR and AF groups (RR = 0.95, 95% CI: 0.59 to 1.54, p = .85).

CONCLUSION

Currently available evidence suggests no significant disparity in postoperative outcomes between TAR and AF. In the short term, TAR demonstrates better clinical scores than AF and lower complication rates. Conversely, in the long term, AF exhibits superior clinical scores and lower complication rates, although this difference is not statistically significant.

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

BACKGROUND

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.

METHODS

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).

RESULTS

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.

CONCLUSION

Based on our results, obesity may have affected long-term outcomes following TAA and may have negatively affected the prosthesis's survival.

Poor survivorship of total ankle replacements. 1368 cases from the period 1994-2021 in the Norwegian arthroplasty register

BACKGROUND AND PURPOSE

The aim of the study was to present the performance of total ankle replacements (TAR) in a national register.

METHODS

All surgeons in the country report to the Norwegian Arthroplasty Register. The completeness of primary TARs in NAR was 79-90% in the years 2017-2020. Cox regression analyses and the Kaplan-Meier method were used to study implant survival and revision risk.

RESULTS

1368 primary TAR´s were implanted in 1266 patients during the period 1994-2021. The last few years saw a marked decrease in the incidence of TARs. The overall survival at 5 years was 81.1% (80.9-81.3) and 69.3% (66.4-72.2) at 10 years. Higher age was strongly associated with better survival. Current prosthesis designs had a better survival than earlier designs ((HRR 0.7, 95% CI 0.6-0.9) CONCLUSION: Revision rates were high in our registry, but current implants had better survival. Younger age increased the risk of revision.

LEVEL OF EVIDENCE

Level II: prospective cohort study.

Body Mass Index (BMI) Cutoffs and Racial, Ethnic, Sex, or Age Disparities in Patients Treated With Total Ankle Arthroplasty

Background

The rising prevalence of obesity among American adults has disproportionately affected Black adults and women. Furthermore, body mass index (BMI) has historically been used as a relative contraindication to many total joint arthroplasty (TJA) procedures, including total ankle arthroplasty. The purpose of this study was to investigate potential disparities in patient eligibility for total ankle arthroplasty based on race, ethnicity, sex, and age by applying commonly used BMI cutoffs to the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.

Methods

Patients in the ACS-NSQIP database who underwent TAA from 2011 to 2020 were retrospectively reviewed in a cross-sectional analysis. BMI cutoffs of <50, <45, <40, and <35 were then applied. The eligibility rate for TAA was examined for each BMI cutoff, and findings were stratified by race, ethnicity, sex, and age. Independent t tests, chi-squared tests, and Fisher exact tests were performed to compare differences at an α = 0.05.

Results

A total of 1215 of 1865 TAA patients (65.1%) were included after applying the exclusion criteria. Black patients had disproportionately lower rates of eligibility at the most stringent BMI cutoff of <35 (P = .004). Hispanic patients had generally lower rates of eligibility across all BMI cutoffs. In contrast, Asian American and Pacific Islander patients had higher rates of eligibility at the BMI cutoffs of <35 (P = .033) and <40 (P = .039), and White non-Hispanic patients had higher rates of eligibility across all BMI cutoffs. Females had lower eligibility rates across all BMI cutoffs. Ineligible patients were also younger compared to eligible patients across all BMI cutoffs.

Conclusion

Stringent BMI cutoffs may disproportionately disqualify Black, female, and younger patients from receiving total ankle arthroplasty.

Level of Evidence

Level III, retrospective cross-sectional study.

Incidence of ankle arthrodesis and total ankle replacement between 1997 and 2018: A nationwide registry study in Finland

BACKGROUND

Surgical treatment options for end-stage ankle osteoarthritis (OA) include ankle arthrodesis (AA) and total ankle replacement (TAR). We investigated the national incidence of AA and TAR and assessed trends in the surgical management of ankle OA in Finland between 1997 and 2018.

METHODS

The Finnish Care Register for Health Care was used to calculate the incidence of AA and TAR based on sex and different age groups.

RESULTS

The mean age (SD) of patients was similar, 57.8 (14.3) years for AA and 58.1 (14.0) for TAR. TAR showed a 3-fold increase from 0.3 per 100 000 person-years in 1997 to 0.9 per 100 000 person-years in 2018. The incidence of AA operations decreased during the study period from 4.4 per 100 000 person-years in 1997 to 3.8 per 100 000 person-years in 2018. TAR utilization increased notably at the expense of AA between 2001 and 2004.

CONCLUSION

TAR and AA are both widely used procedures in the treatment of ankle OA, with AA being the favored option for most patients. The incidence of TAR has remained constant for the past 10 years, indicating appropriate treatment indications and utilization.

Systemic medical complications following total ankle arthroplasty: A review of the evidence

BACKGROUND

Total Ankle Arthroplasty (TAA) is increasingly undertaken for the treatment of end-stage ankle arthritis. For each TAA procedure informed consent is required. The consent process should include discussion of the relevant complications, both systemic and regional. There is a lack of data regarding the systemic complications of TAA. This might cause problems in obtaining valid informed consent.

METHODS

We reviewed and summarised the literature regarding the systemic complications and mortality rate of TAA.

RESULTS

The average rate of systemic medical complications after TAA was 3% (range: 0-7%). The average mortality rate following TAA was 0.3% (range: 0-0.72%). The following were risk factors for systemic medical complications: obesity, diabetes, systemic co-morbidities, preoperative blood transfusion, revision procedures, and long anaesthetic duration.

CONCLUSIONS

When obtaining informed consent for TAA a systemic complication rate of 3% and a mortality rate of 0.3% ought to be included and documented.

Long-term Follow-up of 254 Ceramic Coated Implant (CCI) Evolution Total Ankle Replacements

BACKGROUND

The ceramic coated implant (CCI) Evolution was a third-generation implant design used in approximately 2000 total ankle replacements (TARs) between 2003 and 2016. Because this implant was abandoned, long-term follow-up studies are lacking.

METHODS

All patients undergoing TAR using a CCI prosthesis between 2004 and 2012 were included for analysis. Preoperatively the tibiotalar alignment was measured, and postoperatively the patients were followed up clinically, with radiographs and by questionnaire. The primary outcome was implant survival at 10 years of follow-up. Implant survival was also compared for (1) inflammatory joint disease vs noninflammatory joint disease and (2) preoperative tibiotalar neutral vs varus or valgus alignment. The secondary outcomes were complications, reoperations, and function (assessed by patient-reported outcome measures).

RESULTS

Two hundred fifty-four TARs were performed in 237 patients. Two hundred twelve additional procedures were performed to achieve stable ankles. At 10-year follow-up, the survival was 67.5%, with an average time to revision of 4.5 years. The 10-year survival of the inflammatory joint disease group was 76.8% and of the noninflammatory joint group 63.1% (P = .44). In 248 TARs, the preoperative tibiotalar alignment was measured; (62% neutral, 25% varus, and 13% valgus), these showed 10-year survival rates of 74.7%, 48.2%, and 68.9% respectively (P = .07). The complication rate was 54%; 37% of patients underwent reoperation. At a mean of 8.5 years, postoperative satisfaction scored an average of 7.0 (SD 2.26) on a 0- to 10-point numeric rating scale. The mean Foot and Ankle Ability Measure sports subscore was 24.7, the mean Foot and Ankle Outcome Score (FAOS) sports subscore was 42.8, and the mean 36-Item Short Form Health Survey score was 40.0. Regarding daily activities, the mean FAOS was 81.0.

CONCLUSION

This is currently the sole study reporting the long-term results of the CCI prosthesis. The survival and functional outcomes were inferior to other third-generation mobile-bearing ankle implants.

What is the best way for an inexperienced surgeon to learn total ankle arthroplasty?

BACKGROUND

Previous reports on the learning curve of total ankle arthroplasty (TAA) revealed that inexperienced surgeons should be more careful about operative indications and procedures during the learning curve period. Patients who underwent surgery with inexperienced surgeons may be associated with inferior clinical outcomes, such as frequent complications. This study aimed to evaluate the effect of the participation of experienced surgeons as assistants on the results of TAA performed by inexperienced surgeons.

METHODS

Surgeons whose experience in performing TAA included less than 15 ankles were defined as inexperienced surgeons; on the other hand, those whose experience included more than 20 ankles were defined experienced surgeons in this study. Thirteen ankles operated by inexperienced surgeons, with an experienced surgeon who participated as an assistant, were assigned to the inexperienced group. Fifteen ankles operated on by an experienced surgeon were assigned to the experienced group. TNK Ankle (Kyocera, Kyoto, Japan) was used for all experiments. The coronal and sagittal alignments and the size of the tibial component relative to the tibial shaft were measured. Preoperative and postoperative Japanese Society for Surgery of the Foot (JSSF) and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) were used for clinical assessment.

RESULTS

There were two malleolar fractures during the operation in both groups, and there were no cases of revision surgery. There were no significant differences in the coronal and sagittal tibial component alignment and size between the groups. The JSSF and SAFE-Q improved. There were no significant differences between groups, except for the preoperative JSSF score.

CONCLUSIONS

During the learning curve period, careful surgical indications and surgeries are desired. However, we found that when experienced surgeons participated as assistants, favorable results could be expected even when inexperienced surgeons performed the surgery.

LEVEL OF EVIDENCE

Ⅲ.

Comparison of patient demographics, utilization trends, and costs of total ankle arthroplasty and ankle fusion in the United States from 2010 to 2019

INTRODUCTION

Contemporary studies evaluating utilization and trends of total ankle arthroplasty (TAA) and ankle fusion (AF) for tibiotalar osteoarthritis are sparse. Therefore, the purpose of this study was to utilize a nationwide administrative claims database from 2010 to 2019 to compare: (1) baseline demographics; (2) utilization, (3) in-hospital length of stay (LOS), and (4) costs of care.

METHODS

Using the PearlDiver database, a retrospective query from January 1st, 2010 to December 31st, 2019 was performed for all patients who underwent TAA and AF for tibiotalar osteoarthritis. Baseline demographics, comorbidities, and geographic utilization were compared using Pearson Chi-square analyses. Linear regression was used to compare differences in procedure utilization and in-hospital LOS during the study interval. Reimbursements between the two cohorts during the study interval were compared. A p value less than 0.05 was statistically significant.

RESULTS

In total, 14,248 patients underwent primary TAA (n = 5544) or AF (n = 8704). Patients undergoing AF were generally younger (< 60) with greater comorbidity burden driven by hypertension, diabetes mellitus, obesity, and tobacco use compared to TAA patients (p < 0.0001). Over the study interval, TAA utilization remained constant (912 vs 909 procedures; p = 0.807), whereas AF utilization decreased by 42.5% (1737 vs 998 procedures; p = 0.0001). Mean in-hospital LOS for patients undergoing TAA decreased (2.5 days vs. 2.0 days, p = 0.0004), while AF LOS increased (2.6 days vs. 3.5 days, p = 0.0003). Reimbursements for both procedures significantly declined over the study interval (TAA: $4559-$2156, AF: $4729-$1721; p < 0.013).

CONCLUSION

TAA utilization remained constant, while AF utilization declined by 42.5% from 2010 to 2019. There was divergence in the LOS for TAA versus AF patients. Both procedures significantly declined by over 50% in reimbursements over the study interval.

Survival of primary ankle replacements: data from global joint registries

BACKGROUND

Ankle arthroplasty, commonly known as ankle replacement, is a surgical procedure for treating end-stage ankle osteoarthritis. Whilst evidence shows good clinical results after surgery, little is known of the long-term survival of ankle replacements and the need for ankle revision. Using more recent implant data and long-term data, there is now opportunity to examine at a population-level the survival rate for ankle implants, to examine between-country differences in ankle revision surgery, and to compare temporal trends in revision rates between countries.

METHODS

Four national joint registries from Australia, New Zealand, Norway and Sweden provided the necessary data on revision outcome following primary ankle replacement, for various periods of observation - the earliest starting in 1993 up to the end of 2019. Data were either acquired from published, online annual reports or were provided from direct contact with the joint registries. The key information extracted were Kaplan-Meier estimates to plot survival probability curves following primary ankle replacement.

RESULTS

The survival rates varied between countries. At 2 years, across all registries, survival rates all exceeded 0.9 (range 0.91 to 0.97). The variation widened at 5 years (range 0.80 to 0.91), at 10 years (range 0.66 to 0.84) and further at 15-years follow-up (0.56 to 0.78). At each time point, implant survival was greater in Australia and New Zealand with lower rates in Sweden and Norway.

CONCLUSIONS

We observed variation in primary ankle replacement survival rates across these national registries, although even after 5 years, these population derived data show an 80% revision free survival. These data raise a number of hypotheses concerning the reasons for between-country differences in revision-free survival which will require access to primary data for analysis.