Radiographic and Clinical Outcomes of the Salto Talaris Total Ankle Arthroplasty

Racial Disparities in Outcomes After Foot and Ankle Surgery: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis delved into the impact of race and ethnicity on outcomes following foot and ankle surgery, an area garnering increasing attention within the medical community. Despite significant literature on postsurgical clinical and functional outcomes, limited research has explored the influence of racial and ethnic factors on postoperative outcomes. In this study, data from 33 relevant studies, involving a total of 557,734 patients, were analyzed to assess outcomes across different racial and ethnic groups. Notably, only 6 studies met the criteria for inclusion in the final meta-analysis due to variations in outcome reporting. Findings revealed disparities in functional scores, pain levels, and resource utilization among different racial and ethnic cohorts. Specifically, non-White and minority patients exhibited higher rates of foot and ankle fractures and lower extremity surgeries, worse functional outcomes, increased pain, longer hospital stays, and a greater incidence of complications compared to their White counterparts. However, some studies presented contradictory results, emphasizing the necessity for further investigation to elucidate these discrepancies fully. This research underscores the importance of considering racial and ethnic factors in foot and ankle surgery outcomes and highlights the need for targeted interventions to address existing disparities.

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.

Weight-Bearing Computed Tomography of the Foot and Ankle-What to Measure?

Weight-bearing computed tomography (WBCT) was introduced in 2012 for foot and ankle applications as a breakthrough technology that enables full weight-bearing, three-dimensional imaging unaffected by x-ray beam projections or foot orientation. The literature describing the use of WBCT in the treatment of foot and ankle disorders is growing, and this article provides an overview of what can be measured with WBCT.

Early results of combined total ankle total talus replacement in the revision setting

BACKGROUND

Revision of failed total ankle replacement (TAR) is challenging and associated with increased morbidity. Given the increased popularity of TAR in treating end-stage ankle arthritis (ESAA), viable revision options are needed. The objective of this case series is to present a minimum 2-year clinical and radiographic outcomes of patient-specific custom 3D-printed total ankle total talus (TATR) prostheses in this unique subset of patients.

METHODS

19 participants with ESAA and failed primary TAR who underwent TATR by a single surgeon at our institution from 2019 to 2021 were retrospectively identified. All participants were indicated for revision of primary STAR implant (Stryker, Kalamazoo, MI) and underwent replacement with 3D-printed titanium implants based on preoperative CT analysis (Additive Orthopaedics, Little Silver, NJ). Custom components included a mobile-bearing total talus and stemmed tibial system, performed through an anterior approach. Pre- and postoperative patient-reported outcomes were assessed using the Patient Reported Outcomes Measurement Information System (PROMIS). Pre- and postoperative implant alignment was assessed using medial distal tibial angle (MDTA) and tibiotalar angle (TTA) on anteroposterior, and sagittal tibial angle (STA) on lateral weight-bearing plain films.

RESULTS

The average patient age was 60.6 (range, 39-77) years, with an average follow-up of 37.9 (range, 25.3-57.5) months. There was statistically significant improvement in all PROMIS domains. Short-term survivorship was 100%, with two participants (11.0%) requiring reoperation for postoperative complications: one underwent open reduction internal fixation of the tibia for a periprosthetic fracture, and another underwent medial gutter debridement and tarsal tunnel release for recurrent pain. There were no significant differences in pre- versus postoperative radiographic alignment measured by MDTA (89.9 vs 86.4), TTA (89.7 vs 88.1), or STA (85.2 vs 85.3).

CONCLUSION

Custom 3D-printed TATR is a promising option for revision TAR. There was significant short-term improvement in pain and physical function, with excellent short-term survivorship and an acceptable postoperative complication rate.

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.

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.

Outcomes of Total Ankle Arthroplasty After Periprosthetic Cyst Curettage and Bone Grafting

Total ankle arthroplasty (TAA) has become a popular management option for ankle arthritis. Periprosthetic osteolysis is one of the most common causes for reoperation in TAA. A CT scan should be done in all suspected osteolysis cases to confirm location, quantify size and aid in surgical planning. These patients are often asymptomatic with limited evidence regarding appropriate management. Smaller lesions should be monitored for progression in size. Periprosthetic cysts measuring 10-15mm in all three axes should be considered for debridment and curettage with autogenous bone grafting. The authors believe that bone grafting of large asymptomatic periprosthetic cysts could prevent implant failure.

Outcomes of Total Ankle Arthroplasty After Reoperation due to Gutter Impingement

Gutter impingement is one of the most common causes of subsequent surgery after total ankle arthroplasty (TAA). Although gutter debridement has been reported to resolve preoperative symptoms early on, persistent pain after surgery, recurrence, and poor functional outcome scores have been described in patients who have undergone reoperation for gutter debridement. The cause of gutter impingement after TAA is multifactorial, and a better understanding of its causes and optimal surgical techniques for intervention is needed.

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.

Salto Talaris Fixed-Bearing Total Ankle Arthroplasty: Long-Term Results at a Mean of 10.7 Years

Background

Total ankle arthroplasty (TAA) has become increasingly popular in the treatment for end-stage ankle arthritis in recent decades. However, there is limited evidence regarding the long-term clinical outcomes and complication rates of modern TAA implants.

Methods

This study presents a follow-up on a previous cohort involving 78 patients (81 ankles) who underwent Salto Talaris fixed-bearing TAA to treat end-stage arthritis, with a mean postoperative follow-up of 5.2 years. The aim of this follow-up study was to assess the radiographic (33 patients, 35 ankles) and clinical (48 patients, 50 ankles) results from the original cohort at a mean of 10.7 years (range, 7.8-14 years).

Results

At a mean of 10.7 years, the Kaplan-Meier estimated survivorship was 84.2% (95% CI, 71.9%-98.6%). For the patients reviewed, we did not find any change in patient-reported outcomes between an average 5- and 11-year follow-up. Measured total range of motion and plantarflexion did not change between 1 and 11 years, but dorsiflexion was measured as decreasing by an average of 4 degrees (P < .02).

Conclusion

In this longer-term follow-up of a limited cohort, we found that Salto Talaris fixed-bearing TAA demonstrated good long-term survival with relatively low rates of revision or other complications. Patient-reported outcome and range of motion measures revealed good stability.

Level of Evidence

Level III, therapeutic.

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

BACKGROUND

Despite substantial increase in total ankle arthroplasty (TAA) nationwide, there are few studies comparing flat-cut vs chamfer-cut talar systems in TAA with regard to radiographic aseptic loosening rates of the implant.

METHODS

This retrospective study included 189 Salto-Talaris TAA and 132 INBONE II primary TAA with a minimum 1-year follow-up. Patient characteristics were obtained including gender, age at surgery, body mass index (BMI), smoking status, primary diagnosis, surgical time, and the presence of diabetes. Radiographic evidence for aseptic loosening was assessed. Statistical analysis was performed for comparison in outcomes between Salto-Talaris and INBONE II.

RESULTS

The mean age of the study population was 63.5 ± 9.8 years at surgery. Mean follow-up was 4.9 ± 3.0 years. Radiographic aseptic loosening of the tibial implant showed no significant difference between the 2 groups: Salto-Talaris, 18%, and INBONE II, 18.9% (P = .829). Aseptic loosening of the talar implant also showed no significant difference between the 2 groups: Salto-Talaris, 1.6%, and INBONE II, 1.5% (P = .959). No variables, including the implant type, were found to contribute to the aseptic loosening rate of either the tibia or talus.

CONCLUSION

In our cohort, we observed no difference in radiographic implant aseptic loosening between Salto-Talaris and INBONE II systems.

LEVEL OF EVIDENCE

Level IV, retrospective case series study.

Prospective Multicenter Study of Salto Talaris Ankle Arthroplasty With Minimum 4-Year Follow-Up

BACKGROUND

Total ankle arthroplasty (TAA) continues to be investigated as a primary treatment for end-stage ankle arthritis. The objective of this study is to report mid- to long-term results of the Salto Talaris TAA using prospectively collected patient-reported outcomes and implant survival rates with 4- to 13-year follow-up.

METHODS

This was a retrospective study of prospectively collected data from 2 multicenter cohort studies from 3 centers. Three hundred fourteen subjects who received a Salto Talaris TAA from 2005 to 2015 were included in the study. Follow-up ranged 4-13 years following index procedure. Outcomes included 36-Item Short Form Health Survey (SF-36) mental and physical component summary scores, pain scores, and adverse events including additional surgeries, revision, or removal of components.

RESULTS

Significant improvements were seen in pain and physical function scores at 2-year follow-up and were generally maintained through most recent follow-up. The survival rate of the prosthesis was >95% (n = 30/32 at >10 years, n = 272/282 at 4.5-10 years). Thirteen patients (4.1%) underwent revision or removal of their prosthesis. Time to revision ranged from 2 months to 6.5 years following the index procedure. Twenty-two patients (7.0%) had additional surgery that did not involve revision or removal of components.

CONCLUSION

Treatment of end-stage ankle arthritis with this implant provided patients with improved pain and functional outcome scores at mid- to long-term follow-up. The significant improvements reported at 2-4 years appeared to endure through the extended follow-up period.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Midterm Clinical Outcomes, Radiographic Outcomes, and Survivorship of the Infinity Total Ankle Arthroplasty

BACKGROUND

The Infinity Total Ankle Arthroplasty (Stryker, Mahwah, NJ) is a low-profile fixed-bearing implant first introduced in 2014. Although the short-term survivorship (2-4 years follow-up) and complication rates of the Infinity TAA have been reported, there are limited midterm outcome reports. The aim of this study was to describe the survivorship and clinical outcomes of a single-center experience with the Infinity implant at minimum 5-year follow-up.

METHODS

Retrospective review of 65 ankles that underwent primary total ankle arthroplasty (TAA) with the Infinity implant was conducted. Mean clinical follow-up was 6.5 years (range, 5.0-8.0). Preoperative and postoperative radiographs were measured to assess tibiotalar alignment, periprosthetic lucencies, and cysts. Preoperative, 2-year, and 5-year postoperative Foot and Ankle Outcome Score (FAOS) subscores were compared to assess midterm clinical outcomes. Survivorship assessment was determined by removal of 1 or both metallic implant components.

RESULTS

Survivorship of the implant was 93.8% at final follow-up. There were 4 revisions: 2 for tibial implant loosening, 1 for talar loosening, and 1 for loosening of both components. Three of the 4 revisions occurred within the first 2 years following implantation, and the last failure occurred at 7 years postoperatively. There were 11 reoperations in 10 (15%) ankles and 3 wound complications. There were 17 ankles (26.2%) with radiographic abnormalities around the implants, including 14 cases with tibial component lucencies and 4 cases of periimplant cysts. FAOS outcome measurement showed general stability between 2 and 5 years and substantial improvement from preoperative status.

CONCLUSION

To date this study is the largest midterm report on the Infinity total ankle prosthesis, with 65 implants at a mean follow-up of 6.5 years. We found good midterm implant survivorship, and patients experienced significant improvements in FAOS outcome scores and radiographic alignment at final follow-up.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Outcomes of Total Ankle Arthroplasty in Postfracture Ankle Arthritis

BACKGROUND

Ankle arthritis that develops after fracture accounts for a significant portion of ankle arthritis necessitating total ankle arthroplasty (TAA). It remains unknown whether TAA in postfracture patients produces equivalent outcomes to those without fracture history. The purpose of this study was to evaluate the medium-term outcomes of TAA in postfracture ankle arthritis compared to those without fracture history.

METHODS

This study reviewed 178 ankles from 171 consecutive patients who underwent TAA in our institution between 2007 and 2017 and completed a minimum 5-year follow-up. Four different TAA systems were utilized by 6 surgeons. Based on fracture history, patients were divided into 2 groups: the postfracture group (n = 63; median age 65.7 years; median follow-up 5.9 years) and the nonfracture group (n = 115; median age 64.4 years; median follow-up 6.2 years). Types and rates of complications including revision and reoperation were compared. Minimum 5-year Foot and Ankle Outcome Score (FAOS) and postoperative improvement were investigated. A subgroup analysis was performed to determine whether outcomes differ between intraarticular fracture patients (n = 43) and extraarticular fracture patients (n = 20).

RESULTS

Both groups exhibited comparable postoperative improvement and final FAOS scores. The postfracture group had a significantly higher reoperation rate than the nonfracture group (20 of 63, 31.7%, vs 17 of 115, 14.8%; P = .011), with gutter impingement being the most common cause. There were 3 revisions in each group. In the subgroup analysis, we found no evidence of statistical difference between the intraarticular fracture group and the extraarticular fracture group in terms of FAOS scores, revision, and reoperation rates.

CONCLUSION

In this single-center, retrospective comparative study, we found total ankle arthroplasty in patients with a history of fractures around the ankle joint had no evidence of statistical difference in patient-reported outcomes and implant survivorship but led to a higher rate of nonrevision reoperation following surgery. In the much smaller subset of patients with previous fracture, we did not find that those with a history of intraarticular fracture had inferior outcomes after TAA when compared to those with a history of extraarticular fracture.

LEVEL OF EVIDENCE

Level III, case-control study.

Weight-Bearing Computed Tomography of the Foot and Ankle-What to Measure?

Weight-bearing computed tomography (WBCT) was introduced in 2012 for foot and ankle applications as a breakthrough technology that enables full weight-bearing, three-dimensional imaging unaffected by x-ray beam projections or foot orientation. The literature describing the use of WBCT in the treatment of foot and ankle disorders is growing, and this article provides an overview of what can be measured with WBCT.

Clinical Outcomes of the Lateral Trabecular Metal Total Ankle Replacement at a 5-Year Minimum Follow-up

BACKGROUND

The Trabecular Metal (Zimmer Biomet, Warsaw, IN) total ankle arthroplasty (TAA) system uses a lateral approach with a fibular osteotomy to gain access to the tibiotalar joint and a sagittally curved tibial component. This is the first TAA system to laterally approach the ankle, and few studies have explored outcomes associated with this implant. This study aimed to report the 5-year clinical and radiographic outcomes as well as the survivorship of the implant.

METHODS

Over a 3-year period, 2 fellowship-trained foot and ankle surgeons used this implant system to treat 38 end-stage arthritic ankles. Reoperation and revision data were collected from all patients (100%) as part of the local prospective database. Patients completed the Foot and Ankle Outcome Score (FAOS) questionnaire preoperatively and at each annual follow-up visit; scores for a minimum of 5 years were available for 28 (73.7%) patients. A radiographic analysis compared postoperative coronal and sagittal alignment in weightbearing radiographs at a minimum of 5 years with that at 3 months postoperatively, as well as cyst or lucency formation, which was available for 21 patients (55.3%).

RESULTS

At 5 years, there were 3 revisions (7.9%) and 9 reoperations (23.7%). Reoperations included 4 fibular hardware removal and 5 medial gutter debridement procedures. The FAOS significantly improved for all domains (P < .05). Implant positioning did not significantly change between 3 months and 5 years postoperatively.

CONCLUSION

Our 5-year results in this small series using this unique prosthesis showed good overall survivorship (92.1%) and a reoperation rate of 23.7%, along with clinically significant improvement in patient-reported outcomes.

LEVELS OF EVIDENCE

Level IV: Retrospective case series.

Mid-term functional outcomes following reoperation after total ankle arthroplasty: A retrospective cohort study

BACKGROUND

Despite a significant reported rate of non-revision reoperation after total ankle arthroplasty (TAA), it is uncertain if these subsequent procedures have an impact on the longer term outcomes. This study aimed to compare minimum five-year functional outcomes of patients who had undergone reoperation after TAA to those who did not require reoperation.

METHODS

Seventy-six ankles (74 patients) who underwent TAA with the Salto Talaris fixed bearing system between 2007 and 2014 were allocated into two groups based on presence (n = 16) or absence of reoperation (n = 60). Reoperations included all secondary procedures after index TAA, excluding revision surgeries requiring removal or exchange of the original prosthesis. The foot and ankle outcome score (FAOS) at preoperative and minimum five-year follow-up was compared between the groups. Additionally, improvements in FAOS subscales were compared. Preoperative deformity, postoperative implant alignment, number of periprosthetic cysts, and subsidence between groups were compared using standard weightbearing radiographs.

RESULTS

The most common cause of reoperation was gutter impingement (n = 11), followed by stress fracture of the medial malleolus (n = 2), tarsal tunnel syndrome (n = 1), periprosthetic cyst (n = 1), and infection (n = 1). In comparison to the non-reoperation group, all FAOS subscales except for the Sports and Recreational Activities subscale were significantly lower in the reoperation group at final follow-up. The reoperation group exhibited significantly less improvement in the Pain, Symptoms, and Quality of Life subscales at final follow-up (p < 0.05). There were no statistical differences in the radiographic parameters between both groups.

CONCLUSIONS

Patients who underwent reoperation after TAA demonstrated inferior functional outcomes at mid-term follow-up. An emphasis should be placed on preventing possible causes of reoperations to achieve favorable patient outcomes. Additionally, if a reoperation is deemed necessary, a thorough evaluation and surgical correction of underlying causes should be achieved.

Early Radiographic and Clinical Outcomes of a Novel, Fixed-Bearing Fourth-Generation Total Ankle Replacement System

BACKGROUND

The Cadence Total Ankle System is a 2-component, fixed-bearing fourth-generation total ankle arthroplasty (TAA) system that was introduced for clinical use in 2016. The purpose of this study was to report non-inventor, non-industry funded survivorship, radiographic and clinical outcomes, and early complications following use of this implant at a minimum of 2 years.

METHODS

This single-center retrospective study included patients who underwent TAA by 2 surgeons with this novel fixed-bearing system between January 2017 and September 2018. Forty-eight patients were evaluated at an average of 33.6 months. Radiographic outcomes included preoperative and postoperative tibiotalar angle on anteroposterior radiographs of the ankle, sagittal tibial angle (STA) on lateral radiographs of the ankle, and periprosthetic lucency formation and location. Revision and reoperation data were collected, and patient-reported outcomes were assessed using Patient Reported Outcomes Measurement Information System (PROMIS). Subgroup analysis assessed associations between preoperative deformity, postoperative implant alignment, PROMIS scores, and periprosthetic lucency formation.

RESULTS

Survivorship of implant was 93.7%, with 3 revisions, 1 due to infection and 2 due to loosening of the implant (1 tibial and 1 talar component). Three patients had reoperations (6.3%): 2 for superficial infection and 1 for gutter debridement due to medial gutter impingement. Fifteen patients (35.8%) developed periprosthetic lucencies, all on the tibial side. PROMIS scores improved after surgery in all domains except Depression. Patients with significant postoperative periprosthetic lucency had worse postoperative PROMIS Physical function scores than patients without lucency (P < .05).

CONCLUSION

This study demonstrated excellent minimum 2-year clinical and radiographic outcomes and low revision and reoperation rates of this new fourth-generation TAA system. Future studies with longer follow-up, especially on patients with periprosthetic lucency, are necessary to investigate the long-term complications and understand the long-term functional and radiographic outcomes of this implant.

Retrospective Comparison of Midterm Survivorship, Radiographic, and Clinical Outcomes of the INBONE II and Salto Talaris Total Ankle Arthroplasty Systems

BACKGROUND

Prior studies on the INBONE II and Salto Talaris total ankle arthroplasty (TAA) systems have reported promising outcomes for both implants. This retrospective study aimed to compare the midterm differences between INBONE II and Salto Talaris TAA.

METHODS

Between 2007 and 2015, a total of 44 INBONE II consecutive cases and 85 Salto Talaris consecutive cases had minimum 5-year clinical and radiographic follow-up. Preoperative and midterm survivorship, postoperative Foot and Ankle Outcome Score (FAOS), and radiographic measures including tibiotalar alignment (TTA), medial distal tibial angle (MDTA), and sagittal tibial angle (STA) were compared.

RESULTS

Survivorship to revision was 97.6% (95% CI, 93.1%-100%) for the INBONE II group and 97% (95% CI, 93%-100%) for the Salto Talaris group (P = .93). Survivorship to reoperation was significantly different: 95.5% for the INBONE II and 76.4% for Salto Talaris (P = .021). Postoperative FAOS pain (P = .01), symptoms (P = .004), and sports activity (P = .02) scores were significantly higher in the INBONE II group. The INBONE group had greater preoperative deformity (varus TTA P < .001, valgus TTA P = .02, valgus MDTA P = .005).

CONCLUSION

Although both implants had similar longevity and postoperative alignment, the INBONE II resulted in greater clinical improvement and fewer reoperations than the Salto Talaris at midterm follow-up.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Intermediate to Long-Term Follow-up of the Salto Talaris Fixed-Bearing Total Ankle Prosthesis

BACKGROUND

Total ankle arthroplasty (TAA) remains a viable option for recalcitrant, end-stage ankle arthritis. Among the various Food and Drug Administration (FDA)-approved prosthetic options is the fixed-bearing Salto Talaris implant. The aim of the present study was to evaluate the intermediate to long-term clinical outcomes and radiographic complications following implantation of the Salto Talaris TAA.

METHODS

Nineteen Salto Talaris total ankle implants were included in the present retrospective study. Medical records were reviewed to determine pre- and postoperative visual analog scale (VAS) pain scores, and both medical records and radiographs were utilized to assess for complications. Telephone interviews were then conducted to assess for overall patient satisfaction.

RESULTS

At a mean follow of 6.9 years (range, 3.5-12 years), there was a 21% complication rate according to the classification system described by Glazebrook et al. The reoperation rate was low at 10.5%, and there was 100% survivorship of the total ankle implant. The average pain decreased from 9.1 (range, 7-10) preoperatively to 2.6 (range, 0-10) postoperatively. Patients reported a 95% satisfaction rate, and 16% of patients reported using a brace postoperatively.

CONCLUSION

The Salto Talaris arthroplasty was associated with low complication and reoperation rates, and a high survivorship at intermediate to long-term follow-up.

LEVELS OF EVIDENCE

4.

Midterm Survivorship of the INBONE II Total Ankle Arthroplasty

BACKGROUND

The use of total ankle arthroplasty (TAA) in the treatment of ankle arthritis has grown substantially as advancements are made in design and surgical technique. Among the criteria guiding the choice between arthroplasty and arthrodesis, the long-term survival and postoperative outcomes are of crucial importance. Although outcomes of the INBONE I have been published, there is limited midterm survival data for the INBONE II. The purpose of this study was to determine the radiographic and patient-reported outcomes, and survivorship of this prosthesis in patients with a minimum 5-year follow-up.

METHODS

We retrospectively identified 51 ankles (46 patients) from 2010 to 2015 who underwent TAA with the INBONE II prosthesis at our institution. Of these, 44 cases had minimum clinical follow-up of 5 years (mean, 6.4; range 5-9). Median age was 66 years (range 42-81) and median BMI was 27.5 (range 20.1-33.0). A chart review was performed to record the incidence of revision and reoperation. Preoperative and postoperative radiographs were analyzed to assess the coronal tibiotalar alignment (TTA), the talar inclination angle, and the presence of periprosthetic lucencies and cyst formation. Preoperative and minimum 5-year postoperative Foot and Ankle Outcome Score (FAOS) subscales were compared. Survivorship was determined by incidence of revision, defined as removal of a metallic component.

RESULTS

The survivorship at 5 years was 98% and the rate of reoperation was 7.8% (n = 4); 2 patients underwent irrigation and debridement for infection, 1 patient underwent a medializing calcaneal osteotomy, and 1 patient underwent open gutter debridement, 1 patient underwent a revision of a subsided talar component at 3.2 years after index surgery. Average postoperative TTA was 88.6 degrees, with 42 rated as neutral (85-95 degrees), 2 varus (<85 degrees), and no valgus (>95 degrees) ankles. At final follow-up, asymptomatic periprosthetic cysts were observed in 8 patients. All FAOS domain scores improved between preoperative and final follow-up.

CONCLUSION

At midterm follow-up, we observed significant improvement in radiographic alignment and patient-reported outcome scores for the INBONE II total ankle prosthesis. In addition, this cohort has had a relatively low reoperation rate and high survivorship.

LEVEL OF EVIDENCE

Level IV, case series.

CT Scan Assessment and Functional Outcome of Periprosthetic Bone Grafting After Total Ankle Arthroplasty at Medium-term Follow-up

BACKGROUND

Periprosthetic cysts can occur in up to 95% of total ankle arthroplasties (TAA) and have been correlated with implant failure. The aim of this study was to determine the clinical and radiologic outcomes, using computed tomographic (CT) scan, after periprosthetic cyst bone grafting and assess for the minimum cyst size that should be grafted.

METHODS

A retrospective review was performed of all TAA procedures performed between 2007 and 2014 (n=93). A CT scan was done to assess cyst size and operative planning. Eight patients with 9 periprosthetic cysts larger than 1.75 cm³ were grafted and specimens sent for histology. The mean time to bone grafting was 7.3 (3.8-9.5) years. Functional outcome was assessed using the American Orthopaedic Foot & Ankle Society ankle score, visual analog scale, and Self-reported Foot and Ankle Score. A CT scan was performed at follow-up to assess graft incorporation and cyst size progression. The mean time to CT scan post grafting was 3.0 (0.7-4.7) years.

RESULTS

There was no implant malalignment identified and no differences in the pre- and postoperative functional scores. Preoperatively cysts had a mean volume of 8.16 (2.04-14.03) cm³. The mean percentage incorporation was 89% (69%-100%). Eight of the grafted cysts were considered successful on CT, with the ninth having 69% incorporation. Five cysts were not grafted, as they were below 1.75 cm³, and remained the same size or had minimal enlargement.

CONCLUSION

The satisfactory results in this small cohort suggests that prophylactic bone grafting may extend implant survival. We recommend that periprosthetic cysts greater than 1.75 cm³ be prophylactically bone grafted, and that cysts smaller than 1.75 cm³ be monitored for progression in size.

LEVEL OF EVIDENCE

Level IV, Case Series.

Outcomes and Complications of the INFINITY Total Ankle: A Systematic Review

IV.

Evaluating and Managing the Painful Total Ankle Replacement

The number of total ankle replacements (TARs) performed in the United States has dramatically increased in the past 2 decades due to improvements in implant design and surgical technique. Yet as the prevalence of TAR increases, so does the likelihood of encountering complications and the need for further surgery. Patients with new-onset or persistent pain after TAR should be approached systematically to identify the cause: infection, fracture, loosening/subsidence, cysts/osteolysis, impingement, and nerve injury. The alignment of the foot and ankle must also be reassessed, as malalignment or adjacent joint pathology can contribute to pain and failure of the implant. Novel advanced imaging techniques, including single-photon emission computed tomography and metal-subtraction magnetic resonance imaging, are useful and accurate in identifying pathology. After the foot and ankle have been evaluated, surgeons can also consider contributing factors such as pathology outside the foot/ankle (eg, in the knee or the spine). Treatment of the painful TAR is dependent on etiology and may include debridement, bone grafting, open reduction and internal fixation, realignment of the foot, revision of the implants, arthrodesis, nerve repair/reconstruction/transplantation surgery, or, in rare cases, below-knee amputation.Level of Evidence: Level V, expert opinion or review.

Intermediate-term Patient-Reported Outcomes and Radiographic Evaluation Following Intramedullary- vs Extramedullary-Referenced Total Ankle Replacement

BACKGROUND

The purpose of this study was to report on the radiographic outcomes, clinical outcomes, and implant survivorship following extramedullary-referenced (EMr) vs intramedullary-referenced (IMr) total ankle replacement (TAR).

METHODS

From May 2007 to February 2018, a consecutive series of patients with end-stage tibiotalar osteoarthritis undergoing TAR was enrolled in this study. Analyses were performed comparing IMr vs EMr components for patient-reported outcomes data, pre- and postoperative radiographic ankle alignment, concomitant procedures, and complications. Kaplan-Meier survivorship analyses served to determine implant reoperation and revision surgery. A total of 340 TARs were included with 105 IMr TAR and 235 EMr TAR. The mean follow-up was 5.3 years (±2.5, range 2-12).

RESULTS

The absolute value for preoperative coronal alignment was significantly greater for IMr compared to EMr TAR (13.0 vs 6.4 degrees; P < .0001), but both groups achieved near neutral alignment postoperatively (1.4 vs 1.5 degrees; P = .6655). The odds of having a concomitant procedure was 2.7 times higher in patients with an IMr TAR (OR 2.7, CI 1.7-4.4; P < .0001). There were similar improvements in patient-reported outcome scores at 1 year and final follow-up (all P > .05). The 5-year implant survivorship was 98.6% for IMr vs 97.5% for EMr at final follow-up.

CONCLUSION

The IMr and EMr TAR components had comparable postoperative alignment, patient-reported outcome scores, and complications. The 5-year implant survivorship was similar between the IMr and EMr groups.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.