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

A systematic review of outcomes of total ankle arthroplasty with INBONE II

BACKGROUND

This study systematically reviews the literature and reports on outcomes of total ankle arthroplasty (TAA) with the INBONE II fixed-bearing implant.

METHODS

PubMed, SCOPUS and CINAHL were searched for clinical studies reporting INBONE II specific outcomes from database inception through July 13th, 2024, according to the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines.

RESULTS

Seven primary TAA studies and 4 revision TAA studies were included with 406 and 114 patients respectively. Survivorship was 96.5 % (mean follow-up 44.8 months) and 93.9 % (mean follow-up=37.3 months) for primary and revision TAA, respectively. The mean reoperation rate was 11.4 % with a 3.2 % rate of major complications for primary TAA. Meanwhile, the reoperation rate was 9.1 % with a major complication rate of 12.2 % for revision TAA.

CONCLUSIONS

Primary and revision TAA with this implant results in over 93 % survival at mid-term follow-up with an acceptable complication rate, supporting its continued use.

LEVEL OF EVIDENCE

Level IV: Systematic Review of Level I-IV Studies.

Outcomes of Total Ankle Replacement

Total ankle replacement (TAR) is an effective operative treatment of end-stage ankle osteoarthritis (OA) in the appropriate patient, conferring improved kinematic function, decreased stress across adjacent joints, and offering equivalent pain relief in comparison to ankle arthrodesis (AA). It is important to consider patient age, weight, coronal tibiotalar deformity, joint line height, and adjacent joint OA to maximize clinical and patient outcomes. Both mobile-bearing and fixed-bearing implants have demonstrated favorable clinical outcomes, marked improvement in patient-reported outcomes, and good survivorship; however, implant survivorship decreases with longer term follow-up, necessitating constant improvement of primary and revision TAR options.

Fixed-bearing versus mobile-bearing total ankle replacement survivorship. A meta-analysis

BACKGROUND

Main objective of this research is to know if there is a different survival rate between fixed bearing (FB) and mobile bearing (MB) total ankle replacement (TAR). We hypothesized that there are no differences between the survival rates of both implants.

METHODS

A systematic search was performed in PubMed, Cochrane, EMBASE and ClinicalTrials.gov databases‎ to identify published studies from August 2018 to September 2022 including results for FB and MB TAR survivorship. Inclusion criteria included 1) primary TAR in one or both feet in which implant could be identified‎, 2) a minimum of 20 procedures reported, 3) reported implant survivorship or calculable and 4) a minimum of 12 months follow-up for level 1-3 studies or 60 months for level 4 studies.

RESULTS

3902 ankles in 28 studies were included. 719 were FB and 3104 MB with an overall survivorship of 94% (95% CI [0.89; 0.97]) and 89% (95% CI [0.86; 0.92]) respectively. After subgroup analysis, we did not find differences among both groups (p = ‎0.429‎). Meta-regression analysis showed that longer follow-up was associated with lower survival rates in MB group (p = 0.000) while no other relationships were found with other factors (age, level of evidence or conflict of interests).

CONCLUSIONS

No differences in survival rates between both groups were found. Age and other studied confounders were not found to be related with implant survivorship. However, longer follow-up was found to be related with lower survival rates. Studies with longer follow-up and higher level of evidence are needed to confirm results.

LEVEL OF EVIDENCE

IV, systematic review of level I to IV studies.

Radiographic Analysis of Valgus Ankle Deformity With or Without Medial Longitudinal Arch Collapse

BACKGROUND

Establishing a surgical plan for ankle deformities necessitates a comprehensive understanding of the deforming forces involved, and the morphology of the ankle deformity plays an important role as well. Valgus tibiotalar tilt development has mostly been described in patients with a low medial longitudinal arch, as seen in progressive collapsing foot deformity (PCFD). However, some valgus ankles demonstrate no radiographic evidence of a collapsed medial arch. This study aims to investigate whether there are differences in the radiographic morphology of valgus ankle deformities between patients with and without a low medial longitudinal arch to explore if they have different etiologies.

METHODS

We retrospectively reviewed patients who underwent surgical treatment for asymmetric valgus ankle deformity at our institution between 2017 and 2021. Patients with a valgus tibiotalar tilt (TT) greater than 4 degrees and Meary angle greater than 30 degrees (mean: 38.9) were included in the PCFD group (n = 29). The non-PCFD group (n = 24) with TT greater than 4 degrees and Meary angle less than 4 degrees (mean: 0.3) was also established. In the weightbearing ankle anteroposterior view, the TT and medial distal tibial angle were measured. Additionally, to assess the mediolateral position of the talus, the talar center migration (TCM) and lateral talar dome-plafond distance (LTD-P) ratio in the coronal plane were measured. In weightbearing computed tomography (WBCT), the degree of axial plane talocalcaneal subluxation and the prevalence of sinus tarsi bony impingement were assessed. Intergroup comparison was conducted.

RESULTS

Both groups demonstrated a similar degree of TT, with a mean of 11.6 degrees in the PCFD group and 13.7 degrees in the non-PCFD group (P = .2330). However, the PCFD group showed a significantly greater TCM and LTD-P ratio compared with those of the non-PCFD group (P < .0001), indicating that PCFD patients have a more medially translated talus in ankle anteroposterior radiographs. WBCT showed that the PCFD group on average had 18 degrees greater axial plane talocalcaneal subluxation (P < .0001) and 52% higher prevalence of sinus tarsi bony impingement (P = .0002) compared with the non-PCFD group.

CONCLUSION

This study suggests that valgus ankles may exhibit different radiographic morphologies depending on the status of the longitudinal arch. Valgus ankles in PCFD patients tend to have a more medially translated talus. This finding may suggest the presence of different deforming forces between the 2 groups and may indicate the need for different treatment strategies to address talar tilt.

LEVEL OF EVIDENCE

Level III, case-control.

Navigating the Challenges of Total Ankle Replacement: Deformity Correction and Infection Considerations

In recent years, total ankle replacement (TAR) has gained widespread acceptance as a surgical treatment for end-stage ankle arthritis. This shift is due to notable improvements in implant design, surgical instrumentation, technique, and surgeon expertise, resulting in high levels of patient satisfaction comparable to ankle fusion. Additionally, indications for TAR have expanded to include advanced deformities that were previously considered unsuitable for the procedure, making ankle arthrodesis the only option. Despite these advancements, TAR still carries a higher complication rate compared to other ankle surgeries. The complex anatomy of the ankle, coupled with limited soft tissue, presents significant challenges in managing complications associated with TAR.

Two to Five-Year Outcomes of Total Ankle Arthroplasty with the Infinity Fixed-Bearing Implant: A Concise Follow-up of a Previous Report

LEVEL OF EVIDENCE

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

Outcomes in Ankle Replacement Study (OARS)

Aims

The aim of this study was to capture 12-month outcomes from a representative multicentre cohort of patients undergoing total ankle arthroplasty (TAA), describe the pattern of patient-reported outcome measures (PROMs) at 12 months, and identify predictors of these outcome measures.

Methods

Patients listed for a primary TAA at 19 NHS hospitals between February 2016 and October 2017 were eligible. PROMs data were collected preoperatively and at six and 12 months including: Manchester-Oxford Foot and Ankle Questionnaire (MOXFQ (foot and ankle)) and the EuroQol five-dimension five-level questionnaire (EQ-5D-5L). Radiological pre- and postoperative data included Kellgren-Lawrence score and implant position measurement. This was supplemented by data from the National Joint Registry through record linkage to determine: American Society of Anesthesiologists (ASA) grade at index procedure; indication for surgery, index ankle previous fracture; tibial hind foot alignment; additional surgery at the time of TAA; and implant type. Multivariate regression models assessed outcomes, and the relationship between MOXFQ and EQ-5D-5L outcomes, with patient characteristics.

Results

Data from 238 patients were analyzed. There were significant improvements in MOXFQ and EQ-5D-5L among people who underwent TAA at six- and 12-month assessments compared with preoperative scores (p < 0.001). Most improvement occurred between preoperative and six months, with little further improvement at 12 months. A greater improvement in MOXFQ outcome postoperatively was associated with older age and more advanced radiological signs of ankle osteoarthritis at baseline.

Conclusion

TAA significantly benefits patients with end-stage ankle disease. The lack of substantial further overall change between six and 12 months suggests that capturing PROMs at six months is sufficient to assess the success of the procedure. Older patients and those with advanced radiological disease had the greater gains. These outcome predictors can be used to counsel younger patients and those with earlier ankle disease on the expectations of TAA.

Total Ankle Arthroplasty for Posttraumatic Fracture Versus Primary Osteoarthritis: An Analysis of Complications, Revisions, and Prosthesis Survival

BACKGROUND

Most outcome studies of total ankle arthroplasty (TAA) do not discriminate by arthritis etiology. The primary purpose of this study was to compare the complications of TAA between posttraumatic fracture osteoarthritis (fracture PTOA) and primary osteoarthritis (POA).

METHODS

Ninety-nine patients who underwent TAA were retrospectively evaluated with a mean follow-up of 3.2 years (range 2 to 7.6 years). 44 patients (44%) had a diagnosis of POA while 55 patients (56%) had a diagnosis of fracture PTOA (40 malleolar fractures [73%], 14 pilon fractures[26%], and 1 talar fracture [1%]). Patient demographics, preoperative coronal plane alignment, postoperative complications, and revision surgery data were collected. Categorical variables were compared with chi square and Fisher exact tests and means with the Student t-test. Survival was assessed with Kaplan-Meier and log-rank analyses.

RESULTS

A higher overall complication rate was associated with fracture PTOA (53%) compared with POA (30%) (P = 0.04). No difference was observed in rates of any specific complication by etiology. Survival, defined as revision surgery with TAA prosthesis retention, was comparable between POA (91%) and fracture PTOA (87%) (P = 0.54). When defined as failure requiring prosthesis explant, POA demonstrated significantly greater survival (100%) as compared with fracture PTOA (89%) (P = 0.03). A higher rate of talar implant subsidence and loosening was noted in TAA with prior pilon (29%) as compared to malleolar fractures (8%) that was not statistically significant (P = 0.07). Fracture PTOA was associated with preoperative valgus deformity (P = 0.04). Compared with varus and normal alignment, preoperative valgus deformity was associated with the need for any revision surgery (P = 0.01) and prosthesis explant (P = 0.02).

CONCLUSIONS

Compared with POA, fracture PTOA was associated with a markedly higher complication rate after TAA and was at higher risk of failure requiring prosthesis explant. Fracture PTOA was markedly associated with preoperative valgus malalignment, an identified risk factor in this series for revision surgery and prosthesis explant. Pilon fractures may represent a group at risk of complications related to talar implant subsidence and loosening compared with malleolar fractures and thus warrants additional investigation.

LEVEL OF EVIDENCE

III.

Time to Revision After Periprosthetic Joint Infection in Total Ankle Arthroplasty: A Systematic Review

While not a common complication after total ankle arthroplasty (TAA), periprosthetic joint infection (PJI) presents a significant risk of implant failure. The primary aim of this systematic review was to evaluate time to revision after PJI in patients who had undergone TAA. An extensive search strategy via electronic databases initially captured 11,608 citations that were evaluated for relevance. Ultimately, 12 unique articles studying 3040 implants met inclusion criteria. The time to revision surgery due to PJI was recorded for each study and a weighted average obtained. The prevalence of PJI was 1.12% (n = 34). We found that the average time to revision due to PJI was 30.7 months, or approximately 2.6 years after the index TAA procedure. By literature definitions, the majority of cases (91.2%, n = 31) were beyond the "acute" PJI phase. The population was divided into 2 groups for further analysis of chronic infections. PJIs before the median were classified as "early" and those after as "late" chronic. The majority of cases (61.8%) were late chronic with an average time to revision of 44.3 months. A smaller number were early chronic (29.4%) with revision within 10.8 months. After summarizing the rates of infection and times to revision reported in the literature, we suggest modifying the current PJI classification to include early chronic and late chronic subgroups so that the total ankle surgeon is better prepared to prudently diagnose and treat PJIs.

Survivorship of 4,748 Contemporary Total Ankle Replacements from the French Discharge Records Database

BACKGROUND

Studies of survivorship of primary total ankle replacements (TARs) beyond 5 years have shown varying results among early and modern designs. National cohorts give valuable insights about TAR outcomes, revision risk factors, and specific designs. The purpose of this study was to investigate implant survivorship and risk factors for revision of contemporary TARs using our national database.

METHODS

This observational study included patients identified in the national PMSI (Programme médicalisé des systèmes d'information) database as having undergone TAR from 2010 to 2019. Demographics, discharge data, concomitant procedures, and type of implant were extracted. Kaplan-Meier estimations were performed to determine time to revision using metal component revision for implant failure and revision for deep infection as end points. Weighted Cox models were used for risk factor analysis, including risks of early revision (within the first 2 years). The adjusted hazard ratios (HRadj) were reported with 95% confidence intervals.

RESULTS

A cohort of 4,748 patients was extracted. The mean age at surgery was 63 years; 43% of the patients were female. The mean follow-up was 5 years (range, 1 to 10 years). Revisions were noted in 817 cases (17%), including 734 with metal component revision and 83 with revision due to deep infection. The 1-year, 2-year, 5-year, and 10-year survivorship free of metal component revision was 95%, 90%, 84%, and 78%, respectively. Younger age, implants derived from second-generation designs, and an institutional volume of ≤10 TARs per year were found to be independent predictors of revision for any cause. In addition to the above factors (except for implant generation), male sex and concomitant osteotomies and/or fusion were found to be significant predictors for any early revision.

CONCLUSIONS

The 10-year survivorship free of metal component revision after TAR was 78%, which was consistent with other national registries. Revisions were associated with young age, associated arthritis or deformities requiring concomitant fusion or osteotomy, and implants derived from second-generation designs. Institutions where >10 procedures were performed per year were associated with better TAR survivorship.

LEVEL OF EVIDENCE

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

The Impact of Coronal Plane Deformity on Ankle Arthrodesis and Arthroplasty

BACKGROUND

Ankle coronal plane deformity represents a complex 3-dimensional problem, and comparative data are lacking to guide treatment recommendations for optimal treatment of end-stage ankle arthritis with concomitant coronal plane deformity.

METHODS

In total, 224 patients treated for end-stage ankle arthritis were enrolled in an observational trial. Of 112 patients followed more than 2 years, 48 patients (19 arthrodesis, 29 arthroplasty) had coronal plane deformity and were compared to 64 patients without coronal plane deformity (18 arthrodesis, 46 arthroplasty) defined as greater than 10 degrees of varus or valgus. The arthroplasty implants used had different internal constraints to intracomponent coronal plane tilting. Patients completed Musculoskeletal Functional Assessment (MFA) and SF-36 preoperatively and at 3, 6, 12, 24, and 36 months postoperatively. Measures included change in SF-36 and MFA, as well as compared reoperation rates and pain scales.

RESULTS

For the groups with coronal plane ankle deformity, the median for the arthrodesis group was 19.0 degrees and the median for the arthroplasty group was 16.9 degrees. In the deformity cohort during the follow-up period, we had 7 major reoperations: 2 in the arthrodesis group and 5 in the arthroplasty group, all with the less constrained implant design. MFA, vitality, and social function of the SF-36 improved for all groups. Patients without preoperative deformities had greater improvement with fusion or replacement at both 2 and 3 years. There was no difference in improvement between those patients with coronal deformity who received arthroplasty vs arthrodesis.

CONCLUSION

Patients with and without coronal plane deformity may benefit from ankle arthroplasty and arthrodesis, although greater improvements may be expected in those without preoperative deformity. In this study, at final follow-up of 3 years, overall we found no meaningful difference in patient-reported outcomes between the patients with preoperative coronal plane deformities whether they had a fusion or a replacement as treatment for end-stage ankle arthritis.

LEVEL OF EVIDENCE

Level II, comparative study.