HINTEGRA revision arthroplasty for failed total ankle prostheses

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.

A Novel Approach to Total Ankle Arthroplasty with Simultaneous Structural Tibial Cut Autograft for Anterior Tibial Bone Defects

Severe bone defects pose a clinical challenge in total ankle arthroplasty (TAA) and are frequently considered contraindicated. We introduce an innovative approach that utilizes a structural tibial cut autograft to address anterior distal tibia bone defects during TAA. This technique is a viable alternative to employing revision TAA systems or resorting to excessively high tibial cuts. Furthermore, it facilitates achieving favorable sagittal alignment and ensures adequate fixation strength of the tibial component.

Five-Year Results of the Salto XT Revision Ankle Arthroplasty

BACKGROUND

The treatment of failed ankle replacements is debated, and little is published about the medium- and long-term results of revision implants. We wanted to examine prosthesis survival and physical function at least 5 years after insertion of the Salto XT revision prosthesis.

METHODS

All consecutive patients operated with a Salto XT revision prosthesis underwent clinical and radiologic examinations preoperatively and after 3, 12, 24, and 60 months. Complications and reoperations are described, and changes in patient-reported outcome measures and clinical scores are reported.

RESULTS

Thirty patients were operated with a Salto XT revision prosthesis between March 2014 and March 2017. Three of these were revised (1 to a fusion and 2 to a new prosthesis), and 3 patients were reoperated with screw removal. A concurrent subtalar fusion was performed on 13 patients, and there was 1 case of likely nonunion after these procedures, but no reoperations. The mean AOFAS score increased from 39.2 (95% CI 30.8-47.5) preoperatively to 75.1 (95% CI 67.3-82.9) after 5 years, and the mean improvement was 34.2 points (95% CI 23.8-44.6). Mean EQ-5D increased from 0.36 (95% CI 0.30-0.42) preoperatively to 0.74 (95% CI 0.64-0.85) after 5 years, an improvement of 0.34 (95% CI 0.19-0.49). Radiolucent lines were present in all but 3 patients. Five-year prosthesis survival was 93% (83.6-100).

CONCLUSION

This is the first study to present medium-term results of this implant. We found good improvement in outcome scores and good implant survival, but also a high prevalence of radiolucent lines.

Revision Total Ankle Arthroplasty Using the INBONE II System

BACKGROUND

The utilization of total ankle arthroplasty (TAA) for managing severe ankle osteoarthritis has become increasingly common, leading to a higher occurrence of revision TAA procedures because of failure of primary TAA. This study aims to examine the clinical results associated with revision TAA using the INBONE II system. Given the growing number of TAA revision procedures and a focus on motion-preserving salvage options, we evaluated our early experience with revision TAA.

METHODS

A retrospective analysis was conducted on a group of 60 presumed noninfected patients who underwent revision TAA with the INBONE II system. Detailed information was collected on patient demographics, implant characteristics, concurrent procedures, and complications. The implant survival was estimated using Kaplan-Meier analysis.

RESULTS

The study revealed high complication rates but generally fair clinical outcomes for revision TAA using the INBONE II system. Complications were observed in 22 patients (36.7%), including persistent pain (n = 6), nerve injury/impingement (n = 5), infection (n = 3), fracture (n = 3), implant failure (n = 3), impaired wound healing (n = 2), and osteolysis (n = 3). The 3-year survivorship rate from reoperation was 92.0% (82.7%-100.0%) whereas the 3-year survivorship rate from major complications was 90.4% (80.8%-100.0%).

CONCLUSION

We report high complication rates but generally fair clinical results for revision TAA utilizing the INBONE II system.

Total Ankle Arthroplasty in Young Patients

With continuing advancements in total ankle arthroplasty (TAA), it is quickly becoming the procedure of choice for older patients with end-stage ankle arthritis. Multiple studies have been conducted on younger patients who have undergone TAA with promising results, but is it the procedure of choice? Considerations of TAA versus ankle arthrodesis, TAA implant longevity, outcomes of revision TAA, and whether patients should be offered an arthrodesis with plans for conversion to arthroplasty may help elucidate whether pursuing ankle arthroplasty in a younger, more active population is the correct approach for surgeons.

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 Revision Total Ankle Replacement

The objective of this study is to provide an up-to-date review of the outcomes of revision total ankle arthroplasty (TAA). Relevant studies published over the last decade were reviewed. Twelve studies were included. At a median follow-up of 4 years, the median survival and reoperation rates were 86% and 16%, respectively. Significant postoperative improvements in patient-reported outcome measures were recorded in 6 studies. Significant improvement in alignment was documented in 1 study only. Revision TAA is a safe procedure that can produce good outcomes. Nevertheless, data relating to long-term outcome are still limited in quantity and duration.

Early Survivorship, Clinical and Radiographic Outcomes of a Modular Augmented Revision Total Ankle Arthroplasty System

BACKGROUND

As the number of total ankle arthroplasties (TAAs) performed annually increases, there is increased demand for modular revision implants. There is limited early survivorship and clinical outcome data for the INVISION Total Ankle Arthroplasty System (Wright Medical Technology/Stryker). This study aims to determine early implant survivorship, complications, and radiographic and patient-reported outcomes (PROs) of the INVISION implant in the revision setting.

METHODS

This is a single-institution retrospective review of adult patients who underwent revision TAA with the INVISION implant with minimum 2-year follow-up. Demographics, complications, radiographic data, and PROs (PROMIS) were collected. The primary outcome was implant survivorship. Secondary outcomes were reoperation, radiographic complications, and PROs.

RESULTS

Nineteen patients underwent revision INVISION TAA with mean follow-up of 3.5 years. INVISION revision TAA was used for tibial (n = 6) or talar (n = 7) component subsidence, recurrent tibiotalar malalignment (valgus = 1, varus = 3), and postinfection bone loss (n = 2). Two-year implant survivorship was 100%. There were no reoperations. One patient had lucency of the talar component at 6 months post TAA revision with INVISION. One patient had talar subsidence at final follow-up. Two-year postoperative follow-up PROMIS domains improved significantly (P < .05).

CONCLUSION

There was excellent short-term survivorship of the INVISION TAA implant, with no failures. There were significant improvements in PROs and low rates of subsidence and lucencies. The results of this study support using the INVISION implant in the revision TAA setting.

LEVEL OF EVIDENCE

Level III, retrospective cohort.

Lack of Consensus on the Definition of Aseptic Loosening in Total Ankle Replacement: A Narrative Systematic Review

Background: Aseptic loosening is one of the most common modes of failure of total ankle replacement (TAR). However, a precise definition of aseptic loosening is still lacking. This systematic review aimed to identify the variations of applied definitions and offer insights into the lack of consensus. Methods: Human studies reporting aseptic loosening of TAR published in peer-reviewed journals within the last decade were considered. The search strategy involved specific terms in Embase, MEDLINE ALL, and the Cochrane Library. Variations in aseptic loosening definitions were analysed. Results: Of 767 studies, 88 were included in this study. Only nine studies precisely defined aseptic loosening with significant variations. Twenty-two studies referenced the term and fifty-seven reported it as a complication but neither defined nor referenced it. Conclusions: Significant uncertainty exists regarding the universal definition of aseptic loosening of TAR, and many variations occur in terms of the assessment approach and criteria.

Revision of total ankle arthroplasty: Survival and medium-term functional results

BACKGROUND

The objective of this study was to analyze the results and survivorship of total ankle arthroplasty (TAA) revision surgery with standard (Salto Talaris®) or revision (Salto Talaris XT®) implants.

METHODS

Between January 2005 and December 2017, all patients undergoing TAA revision at our hospital were included. Indications for revision, type of surgery performed, improvement in function assessed with the AOFAS score, occurrence of complications and implant survival at last follow-up were analyzed.

RESULTS

In the end, 25 TAA patients who had undergone revision (11 unipolar, 14 bipolar) were included. The mean follow-up time was 5.1 ± 1.9 years. At the last follow-up, function was improved compared to the preoperative AOFAS score (51.3 ± 17.5 vs. 83.5 ± 10.1; p < .001), but not plantar flexion (17.5 ± 5.7 vs. 15.4 ± 7.1; p = 0.28) or dorsal flexion (7 ± 5.6 vs. 8.3 ± 4.9; p = 0.3). Complications occurred in six patients (24 %) that led to reoperation: three infections, one lateral impingement, one implant malposition, and one hindfoot alignment disorder. At the last follow-up, implant survival was 96 %, but the probability of survival without reoperation was 78.7 ± 8.5 % at 4 years.

CONCLUSION

TAA revision by arthroplasty is feasible, produces good functional results in the medium term, but has a high risk of complications. The challenge of revision TAA is managing the loss of bone stock and anchoring the new implants.

Survival and risk assessment in revision arthroplasty of the ankle

Aims

Implant failure has become more common as the number of primary total ankle arthroplasties (TAAs) performed has increased. Although revision arthroplasty has gained attention for functional preservation, the long-term results remain unclear. This study aimed to assess the long-term outcomes of revision TAA using a mobile-bearing prosthesis in a considerably large cohort; the risk factors for failure were also determined.

Methods

This single-centre retrospective cohort study included 116 patients (117 ankles) who underwent revision TAA for failed primary TAA between July 2000 and March 2010. Survival analysis and risk factor assessment were performed, and clinical performance and patient satisfaction were evaluated preoperatively and at last follow-up.

Results

The mean duration from initial revision TAA to last follow-up was 15.0 years (SD 3.0; 11.2 to 20.5). The cumulative survival rates of the revised ankles were 81% (95% confidence interval (CI) 74% to 88%), 74% (65% to 82%), and 70% (61% to 79%) at five, ten, and 15 years, respectively. Comorbidities prior to primary TAA, aseptic loosening, instability, or grafting of cysts were found to be the most common risk factors for secondary revision. The median value for preoperative pain, as assessed using the visual analogue scale, declined from 6 (interquartile range (IQR) 5 to 8) to 2 (IQR 0 to 5) (p < 0.001) and the mean American Orthopaedic Foot and Ankle Society ankle-hindfoot score improved from 43 (SD 17) preoperatively to 70 (SD 20) (p < 0.001) at last follow-up.

Conclusion

Revision TAA offers acceptable survival rates after 15 years; it therefore offers a valuable option for treatment of implant failure in carefully selected cases. Although patient-reported outcomes improve substantially, the degree of improvement reported following primary TAA is not achieved.

Long-Term Survival Analysis of 5619 Total Ankle Arthroplasty and Patient Risk Factors for Failure

BACKGROUND

Total ankle arthroplasty (TAA) has higher complication and failure rates compared to other surgical joint replacement procedures despite technological advances. This study aimed to find the long-term survivability of the TAA procedure and identify the patient risk factors for failure with one of the largest cohorts of patients in the literature.

METHODS

This retrospective cohort study involving cases between 2007 and 2018 analyzed patients who received an index primary TAA procedure in Korea. A total of 5619 cases were included in the final analysis. The TAA failure was defined as either a case with revision arthroplasty or a case with TAA implant removal and arthrodesis performed after primary TAA.

RESULTS

During the study period, the 5-year survival rate was 95.4% (95% CI, 94.7-96.1%), and the 10-year survival rate was 91.1% (95% CI, 89.1-93.1%). A younger age (<55 years, adjusted hazard ratio [AHR], 1.725; 55-64 years, AHR, 1.812; p < 0.001 for both), chronic pulmonary disease (AHR, 1.476; p = 0.013), diabetes (AHR, 1.443; p = 0.014), and alcohol abuse (AHR, 1.524; p = 0.032) showed a significantly high odds ratio for primary TAA failure in Cox regression analysis.

CONCLUSION

The 10-year TAA survivorship rate was 91.1%. A younger age, chronic pulmonary disease, diabetes, and heavy alcohol consumption are risk factors for TAA.

Total Ankle Replacement Infections: A Systematic Review of the Literature

Periprosthetic infection (PJI) after TAR is a serious complication, often requiring further surgery, including revision arthroplasty, conversion to ankle arthrodesis, or even amputation. This systematic review aims to summarize the current evidence on the management of TAR PJI and provide a comprehensive overview of this topic, especially from an epidemiologic point of view. Three different databases (PubMed, Scopus, and Web of Science) were searched for relevant articles, and further references were obtained by cross-referencing. Seventy-one studies met the inclusion criteria, reporting on cases of TAR PJI. A total of 298 PJIs were retrieved. The mean incidence of PJI was 3.8% (range 0.2-26.1%). Furthermore, 53 (17.8%) were acute PJIs, whereas most of them (156, 52.3%) were late PJIs. Most of the studies were heterogeneous regarding the treatment protocols used, with a two-stage approach performed in most of the cases (107, 35.9%). While the prevalence of ankle PJI remains low, it is potentially one of the most devastating complications of TAR. This review highlights the lack of strong literature regarding TAR infections, thus highlighting a need for multicentric studies with homogeneous data regarding the treatment of ankle PJI to better understand outcomes.

Use of Femoral Head Allograft for Extended Bone Loss in Revision Total Ankle Arthroplasty: A Case Report

CASE

A 38-year-old male patient presented with severe ankle pain 13 years after a total ankle arthroplasty (TAA). Radiographic evaluation revealed loosening of the implant and extensive osteolytic lesions. The medial tibial plafond and malleolus were reconstructed using a fresh-frozen femoral head graft, and revision TAA was performed. The midterm results were satisfactory, with adequate integration of the allograft and stable implant components.

CONCLUSION

The use of the allograft technique in revision TAA is feasible in the presence of severe bone loss, including the malleoli, and allows firm component fixation of the reconstructed bone.

How Does a Novel In Situ Fixed-bearing Implant Design Perform in Revision Ankle Arthroplasty in the Short Term? A Survival, Clinical, and Radiologic Analysis

BACKGROUND

Given the growing number of primary total ankle replacements (TAR), an increase in the number of patients undergoing subsequent revisions might be expected. Achieving a stable and balanced ankle while preserving the remaining bone stock as much as possible is crucial for success in revision TAR. Most reported techniques rely on bulky implants with extended fixation features. Since 2018, we have used a novel, three-component ankle prosthesis for revision that is converted in situ to a fixed-bearing, two-component ankle prosthesis once the components have found their position according to an individual's anatomy. The results of this novel concept (fixation, revision, pain, or function) have not, to our knowledge, been reported.

QUESTIONS/PURPOSES

What are the short-term results with this new revision TAR design, in terms of (1) repeat revision surgery, (2) patient-reported outcomes on the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, (3) pain according to the VAS, and (4) radiographic signs of fixation?

METHODS

Between February 2018 and February 2020, we performed 230 TAR surgeries (in 206 patients) for any indication in our clinic. The novel semiconstrained, uncemented Hintermann Series H2 © implant was used in 96% (220 of 230) of procedures (201 patients). Fifty-four percent (119 of 220) of these were converted from an existing TAR to H2, which was the focus of the present study. However, only 45% (54 of 119) of these conversions to H2 were eligible for analysis. These patients had a mean age of 63 ± 12 years, and 43% (23 of 54) were women. The median (range) follow-up time was 3.2 years (2.0 to 4.3). The H2 design allows in situ conversion to a fixed-bearing system, with minimal bone resection. It achieves translational and rotational stability while preserving function and supporting the periarticular soft tissues. We defined repeat revision as exchange of one or both metal components, ankle fusion, or amputation and assessed it using a cumulative incidence survivorship estimator. Factors potentially associated with revision were assessed using Cox regression analyses. Clinical and radiologic outcomes were assessed preoperatively and at the most recent follow-up interval. Clinical outcomes included pain on the VAS (average pain during normal daily activity during the past seven days) and AOFAS score. Radiologic outcomes were the tibial articular surface angle, tibiotalar surface angle, talar tilt angle in the coronal plane, and AP offset ratio in the sagittal plane, as well as radiolucent lines and radiographic signs of loosening, defined as change in position greater than 2° of the flat base of the tibia component in relation to the long axis of the tibia, subsidence of the talar component into the talus greater than 5 mm, or change in position greater than 5° relative to a line drawn from the top of the talonavicular joint to the tuberosity of the calcaneus, as seen on plain weightbearing radiographs.

RESULTS

The cumulative incidence of repeat revision after 1 and 2 years was 5.6% (95% CI 0% to 11%) and 7.4% (95% CI 0% to 14%), respectively. With the numbers available, no clinical factors we analyzed were associated with the risk of repeat revision. The median values of all assessed clinical outcomes improved; however, not all patients improved by clinically important margins. The median (range) AOFAS ankle-hindfoot score increased (from 50 [16 to 94] to 78 [19 to 100], difference of medians 28; p < 0.01), and the median pain on the VAS decreased (from 5 [0 to 9] to 2 [0 to 9], difference of medians 3; p < 0.01) from before surgery to follow-up at a minimum of 2 years. Radiographically, lucency was seen in 12% (6 of 49 patients) and loosening was seen in 8% (4 of 49). One of these patients showed symptomatic loosening and was among the four patients overall who underwent revision. We could not assess risk factors for repeat revision because of the low number of events (four).

CONCLUSION

The investigated new in situ fixed-bearing ankle design achieved overall better short-term results than those reported in previous research. Destabilization of the ankle joint complex, soft tissue insufficiency, and possible changes of the joint configuration need an optimal solution in revision arthroplasty. The studied implant might be the answer to this complex issue and help surgeons in the perioperative decision-making process. However, a relatively high percentage of patients did not achieve a clinically important difference. Observational studies are needed to understand long-term implant behavior and possibly to identify ankles benefiting the most from revision.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Management of Periprosthetic Bone Cysts After Total Ankle Arthroplasty

Modern improvements in total ankle arthroplasty (TAA) have increased the performance of this procedure for treatment of end-stage ankle arthritis. A common finding after TAA is the formation of periprosthetic bone cysts, which can be clinically silent or result in TAA failure. The exact cause of periprosthetic bones cysts has not been established, but major theories are related to osteolysis secondary to implant wear, micromotion, and stress shielding. Treatment can be nonoperative with clinical observation for small, asymptomatic cysts. Large, progressive, and symptomatic cysts often merit surgical treatment with debridement and grafting, revision TAA, or salvage arthrodesis.

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.

The talar body prosthesis treated end-stage ankle arthritis with talar body deficient: a 6-13 years of follow-up outcomes and 6-year survivorship

INTRODUCTION

Talar body deficient provides a unique challenge for ankle arthritis treatment. We studied the clinical-radiographic outcomes at 6 to 13 years and 6 year prosthesis survivorship of patients treated for ankle arthritis with poor talar body bone stock using a talar body prosthesis (TBP).

MATERIALS AND METHODS

Between 2008 and 2015, we treated 32 consecutive end-stage ankle arthritis patients with talar body deficiency by TBP implantation and fascia interposition. One patient was excluded with a diagnosis of inflammatory arthritis. We assessed visual analogue scale (VAS) of ankle pain, sagittal range of motion, American Orthopaedics Foot and Ankle Society (AOFAS) ankle-hindfoot score, Foot Ankle Ability Measure (FAAM) of activity daily living (ADL), prosthesis tibiotalar surface angle, radiographic prosthesis loosening, adjacent joint arthritis and complication. Pre-operative to last follow-up outcomes (at 6-13 years) were compared. Prosthesis survivorship was analyzed at 6 year follow-up. p < 0.05 was considered a significant difference.

RESULTS

There was statistically significant improvement of median VAS ankle pain, as 8.0 (IQR 1.0) to 1.0 (IQR 2.0), AOFAS ankle-hindfoot score from 48 (IQR 21) to 80 (IQR 7.0), FAAM of ADL from50.0 (28.0) to 88.0 (IQR 15.0), and sagittal ROM from 20^o (IQR 19°) to 33° (IQR 14°), p < 0.05. The median tibiotalar surface angle was statistically significant improved from 85.0° (IQR 8.0°) to 89.0° (IQR 3.0°), p < 0.001. No radiographic prosthesis loosening or adjacent talonavicular-calcaneocuboid joint arthritis. The 6 year prosthesis survivorship was 93.5% (95% CI 84.9-100.0%). End of survivorship was observed in 2 patients due to progressive valgus tilting at 16° and 18°, respectively. No prosthesis was revised.

CONCLUSIONS

TBP implantation with fascia replacing the articular end of distal tibia provided significant better pre- to post-operative clinical outcomes and had 6 year survivorship as 93.5% for the treatment of ankle arthritis with talar body deficient.

LEVEL OF EVIDENCE

IV.

Clinical and Radiographic Outcomes of Revision Total Ankle Arthroplasty Using the INBONE II Prosthesis

BACKGROUND

The literature on the outcome of revision total ankle arthroplasty (TAA) remains limited. In this study, we aimed to report the clinical and radiographic outcomes of revision TAA at a high-volume center in the United Kingdom.

METHODS

This study was a retrospective review of 28 patients who underwent 29 revision TAAs using the INBONE II Total Ankle System (Wright Medical Technology/Stryker). Demographic, radiographic, and patient-reported outcome measure data were analyzed.

RESULTS

The mean duration from primary TAA to revision was 87.5 months (range, 16 to 223 months). The main indication for the revision was aseptic loosening after the primary TAA (83%). Additional procedures were required in 76% of ankles. At a mean follow-up of 40 months (range, 24 to 60 months), the infection rate was 7%, the reoperation rate was 7%, and the implant survival rate was 97%. A significant postoperative improvement in the radiographic component alignment measures was observed. The subsidence, loosening, and heterotopic ossification rates in this study were comparable with those in other reports and did not influence the clinical outcome. A significant improvement was observed in the Manchester-Oxford Foot Questionnaire (MOXFQ) in all domains and the EuroQol-5 Dimensions (EQ-5D) in 3 domains at 24 months postoperatively.

CONCLUSIONS

Revision TAA using the INBONE II prosthesis was associated with good short-term survival and improvement in postoperative scores at 2 years. Maintenance of the postoperatively improved alignment was documented at the follow-up. The results of this study support the notion that revision TAA is a satisfactory option for failed primary TAA.

LEVEL OF EVIDENCE

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

The outcomes of revision surgery for a failed ankle arthroplasty

Aims

Revision rates for ankle arthroplasties are higher than hip or knee arthroplasties. When a total ankle arthroplasty (TAA) fails, it can either undergo revision to another ankle replacement, revision of the TAA to ankle arthrodesis (fusion), or amputation. Currently there is a paucity of literature on the outcomes of these revisions. The aim of this meta-analysis is to assess the outcomes of revision TAA with respect to surgery type, functional outcomes, and reoperations.

Methods

A systematic review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Medline, Embase, Cinahl, and Cochrane reviews were searched for relevant papers. Papers analyzing surgical treatment for failed ankle arthroplasties were included. All papers were reviewed by two authors. Overall, 34 papers met the inclusion criteria. A meta-analysis of proportions was performed.

Results

Six papers analyzed all-cause reoperations of revision ankle arthroplasties, and 14 papers analyzed failures of conversion of a TAA to fusion. It was found that 26.9% (95% confidence interval (CI) 15.4% to 40.1%) of revision ankle arthroplasties required further surgical intervention and 13.0% (95% CI 4.9% to 23.4%) of conversion to fusions; 14.4% (95% CI 8.4% to 21.4%) of revision ankle arthroplasties failed and 8% (95% CI 4% to 13%) of conversion to fusions failed.

Conclusion

Revision of primary TAA can be an effective procedure with improved functional outcomes, but has considerable risks of failure and reoperation, especially in those with periprosthetic joint infection. In those who undergo conversion of TAA to fusion, there are high rates of nonunion. Further comparative studies are required to compare both operative techniques. Cite this article: Bone Jt Open 2022;3(7):596–606.

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.

Clinical efficacy of the Ankle Spacer for the treatment of multiple secondary osteochondral lesions of the talus

BACKGROUND

The Ankle Spacer was developed as a joint-sparing alternative to invasive end-stage surgeries. Currently, there are no clinical studies on the Ankle Spacer.

AIM

To describe the operative technique and the clinical efficacy of the Ankle Spacer for the treatment of multiple, cystic osteochondral lesions of the talus in patients with failed prior operative treatment.

METHODS

This is a prospective study during which patients were assessed preoperatively, at 2- and 6 wk, and at 3, 6, 12 and 24 mo postoperatively. Patients with multiple, cystic or large (≥ 15 mm) osteochondral lesions of the talus after failed prior surgery were included. The primary outcome measure was the numeric rating scale (NRS) for pain during walking at 2 years postoperatively. Secondary outcome measures included the NRS in rest and during stair climbing, the American Orthopaedic Foot and Ankle Society Hindfoot Score, the Foot and Ankle Outcome Score, the Short- Form 36 physical and mental component scale, and the Range of Motion (ROM). Radiographic evaluations were conducted to evaluate prosthetic loosening and subsidence. Revision rates and complications were also assessed.

RESULTS

Two patients underwent an Ankle Spacer implantation on the talus. The NRS during walking improved from 6 and 7 preoperatively to 2 and 2 points postoperatively at 2 years, in patient 1 and 2, respectively. The other patient-reported outcome measures also improved substantially. There were no re-operations nor complications. Radiological imaging showed no loosening of the implant and no change of implant position.

CONCLUSION

The Ankle Spacer showed clinically relevant pain reduction during walking, improvement in clinical outcomes as assessed with PROMs, and no complications or re-operations. This treatment option may evolve as a joint-sparing alternative to invasive end-stage surgeries.

[Salvage options following failed total ankle arthroplasty]

The number of patients with osteoarthritis of the ankle, which are treated by arthroplasty, has continuously increased in recent years. The survival time of these implants is far below the results following hip and knee arthroplasty. In some cases a failure rate of approximately 1% per year or a survival rate of 70% after 10 years has been reported. The most frequent reasons for revision of an ankle prosthesis are aseptic loosening, technical implantation errors and persisting pain. For the revision of an ankle prosthesis there are basically two treatment options. For a long time, ankle arthrodesis was considered the gold standard after a failed prosthesis. In recent years, there has been an increasing trend towards re-implantation of an ankle prosthesis, as this preserves the functionality and mobility of the ankle joint as far as possible. Depending on the reason for failure and the size of the bony defect, a decision must be made regarding a one-stage and a two-stage procedure with bone augmentation. This article presents the advantages and disadvantages of arthrodesis and revision arthroplasty after failed primary ankle arthroplasty and highlights the special features of surgery.

A Prospective Cohort Study Comparing Functional Outcomes of Primary and Revision Ankle Replacements

BACKGROUND

The number of ankle and revision ankle replacements performed is increasing. There is limited research into functional outcomes, especially in revision ankle replacements. The primary aim of this cohort study was to determine the functional improvements following primary and revision ankle replacements and compare which gave the greatest improvement in functional scores.

METHODS

A single-center prospective cohort study was undertaken between 2015 and 2018. All patients were followed up for a minimum of 2 years. Patients undertook a preoperative and 2-year Manchester Oxford Foot Questionnaire (MoxFQ) score. The Mann Whitney test was undertaken.

RESULTS

A total of 33 primary and 23 revision ankle replacements were performed between 2015 and 2018. The mean age was 69.3 years for primary replacements and 64.7 years for revision replacements. All primary replacements were the Infinity ankle replacement. Revision replacements were either the Inbone II or Invision. The indication for revision was 9 aseptic loosening, 6 infections, 5 cysts, and 3 malposition. Seventeen were performed as a single stage and 6 as a 2-stage revision. The overall MoxFQ improved by a mean of 48.8 for primaries and 20.2 for revisions (P = .024). The walking/standing domain improved by 57.5 for primaries and 22.5 for revisions (P = .016), the pain score improved by 43.0 and 32.3 (P = .009), and the social interaction improved by 40.0 and 11.7 (P = .128).

CONCLUSION

Both primary and revision ankle replacements result in improved functional scores. In this relatively small cohort with the implants used, primary ankle replacements though have a significantly greater improvement in functional scores compared to revision ankle replacements.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

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.

Two-Staged Revision Total Ankle Arthroplasty Surgery with Primary Total Ankle Arthroplasty System: A Case Report

CASE

Case of a 2-staged revision surgical technique for the treatment of an aseptic total ankle arthroplasty (TAA) loosening: first surgery: removal of the loosened and painful TAA Scandinavian Total Ankle Replacement, with exclusion of infection, and reconstruction of the large bone defect (bone-defect downsizing surgery); proof of successful ankle bone reconstruction by CT-scan imaging; second surgery: implantation of a primary VANTAGE TAA (ankle reconstruction with new primary TAA).

CONCLUSION

The present case shows the management of a failed TAA with bone defect by performing a 2-step surgical approach: removal of loosened TAA with simultaneous bone stock restoration and then implantation of a new primary TAA. This concept is a possible alternative to a post-TAA ankle arthrodesis or to the use of a TAA revision system.

Retrograde nailing, trabecular metal implant and use of bone marrow aspirate concentrate after failed ankle joint replacement

BACKGROUND

Ankle fusion after removal of alloplasty is known to be a procedure with a high potential for non-unions and poor function, especially tibio-talo-calcaneal fusion. We wanted to review our results after using a novel method for the procedure, combining retrograde nailing with a trabecular metal implant and bone marrow aspirate concentration applied in an ostoconductive pad in addition to autologous bone grafting.

MATERIALS AND METHODS

Retrospective review of a patient series, with some prospectively registered data. 31 ankles in 30 patients were operated from January 2016 to February 2019.

RESULTS

There were two non-unions (6.5%), and one delayed union, none of these were reoperated. The mean postoperative Manchester-Oxford Foot and Ankle Questionnaire score (MOxFQ) was 33.6 points. 9 patients scored an average MOxFQ at 72.9 immediately before surgery, while at follow-up this had decreased to 36.2, an improvement of 36.7 points (95% CI 18.3-54.9). There were 1 minor infection and 5 possible nerve injuries. One patient had the leg amputated 1 year after the surgery due to a non-related necrotizing fasciitis.

CONCLUSION

We present reasonably good short to medium term patient satisfaction and fusion rates with this novel combination of techniques.

Pathogenesis, Evaluation, and Management of Osteolysis Following Total Ankle Arthroplasty

Periprosthetic osteolysis is a common occurrence after total ankle arthroplasty (TAA) and poses many challenges for the foot and ankle surgeon. Osteolysis may be asymptomatic and remain benign, or it may lead to component instability and require revision or arthrodesis. In this article, we present a current and comprehensive review of osteolysis in TAA with illustrative cases. We examine the basic science principles behind the etiology of osteolysis, discuss the workup of a patient with suspected osteolysis, and present a review of the evidence of various management strategies, including grafting of cysts, revision TAA, and arthrodesis.Level of Evidence: Level V, expert opinion.

Clinical and Radiographic Outcomes of Revision Total Ankle Arthroplasty Using an Intramedullary-Referencing Implant

BACKGROUND

Treatment of failed total ankle arthroplasty (TAA) is challenging. Limited literature is available on options and outcomes of revision arthroplasty despite failure rates ranging from 10% to 23% within 10 years after primary TAA. This study reports the clinical and radiographic outcomes of revision TAA using a fixed-bearing, intramedullary-referencing implant.

METHODS

A retrospective review was performed of 18 consecutive revision TAA cases between 2008-2015 using an intramedullary-referencing, fixed-bearing, 2-component total ankle system. Demographic and radiographic data were collected preoperatively, immediately postoperatively, and at the most recent follow-up. Functional outcome data were collected immediately postoperatively and at mean follow-up 47.5 months.

RESULTS

Eighteen patients underwent revision TAA, with 77.8% (14/18) implant survival. Index revision was performed most commonly for aseptic talar subsidence (55.6%) or implant loosening (tibia, 29.4%; talus, 58.9%). Following revision, 22.2% (4/18) patients required reoperation at a mean 57.3 (39-86) months. Osteolysis of the tibia, talus, and fibula was present preoperatively in 66.7% (12/18), 38.9% (7/18), and 38.9% (7/18) of patients, respectively, with progression of osteolysis in 27.8% (5/18), 11.1% (2/18) and 11.1% (2/18) of patients, respectively. Subsidence of the tibial and talar revision components was observed in 38.9% (7/18) and 55.6% (10/18) of patients, respectively. The median American Orthopaedic Foot & Ankle Society (AOFAS) score was 74.5 (26-100) and Foot Function Index (FFI) score 10.2 (0-50.4).

CONCLUSION

Early results of intramedullary-referencing revision TAA demonstrated good patient-reported outcomes with maintenance of radiographic parameters at mean follow-up of 47.5 months. Aseptic talar subsidence or loosening were the main postoperative causes of reoperation. Revision arthroplasty utilizing an intramedullary-referencing implant was a viable option for the failed TAA.

LEVEL OF EVIDENCE

Level IV, case series.

Effect of age on outcome and revision in total ankle arthroplasty

Aims

To assess the effect of age on clinical outcome and revision rates in patients who underwent total ankle arthroplasty (TAA) for end-stage ankle osteoarthritis (OA).

Methods

A consecutive series of 811 ankles (789 patients) that underwent TAA between May 2003 and December 2013 were enrolled. The influence of age on clinical outcome, including the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score, and pain according to the visual analogue scale (VAS) was assessed. In addition, the risk for revision surgery that includes soft tissue procedures, periarticular arthrodeses/osteotomies, ankle joint debridement, and/or inlay exchange (defined as minor revision), as well as the risk for revision surgery necessitating the exchange of any of the metallic components or removal of implant followed by ankle/hindfoot fusion (defined as major revision) was calculated.

Results

A significant improvement in the AOFAS hindfoot score and pain relief between the preoperative assessment and the last follow-up was evident. Age had a positive effect on pain relief. The risk for a minor or major revision was 28.7 % at the mean follow-up of 5.4 years and 11.0 % at a mean follow-up of 6.9 years respectively. The hazard of revision was not affected by age.

Conclusion

The clinical outcome, as well as the probability for revision surgery following TAA, is comparable between younger and older patients. The overall revision rate of the Hintegra total ankle is comparable with other three component designs. TAA should no longer be reserved for low demand elderly patients, but should also be recognized as a viable option for active patients of younger age. Cite this article: Bone Joint J 2020;102-B(7):925–932.

The CT gap sign, a case of failure to seat the polythene component in total ankle replacement (infinity)

We present a case of incorrect seating of the polyethylene liner in an INFINITY total ankle replacement causing discomfort and eventually leading to a revision ankle replacement. This malposition of the implant was observed on a computed tomography (CT) scan as a ‘gap’ between the liner and the body of the replacement. The patient complained of discomfort on walking postoperatively, which limited activity. All investigations were normal including X-Ray, inflammatory markers, ultrasound, and it was only the subtle CT changes along with history that confirmed the diagnosis. This case demonstrates a complication of the design of the INFINITY prosthesis and the approach taken to the ankle when inserting. The patient fortunately made a full recovery after revision surgery, returning to normal activities with minimal pain.

Current concepts in the management of ankle arthritis

Ankle arthritis is a common condition. It causes a significant socioeconomic burden, and is associated with significant morbidity. Patients with ankle arthritis are either elderly with significant co-morbidities, or young adults who have previously suffered with ankle injuries, resulting in post-traumatic arthritis. There is a wide variation in the management of these patients with ankle arthritis. We therefore present an overview of the current evidence based management of patients with symptomatic ankle arthritis.

[Development and clinical application of ankle prosthesis]

OBJECTIVE

To review the development and clinical application of ankle prosthesis.

METHODS

The recent literature on ankle prosthesis design and clinical application was reviewed and analyzed.

RESULTS

Compared with the hip and knee prostheses, the ankle prosthesis develops slowly and has been developed to the third generation. The ankle joint has a special structure of multi-axis movement. The design of the first and second generations of prostheses is not conformed to the biomechanics of the ankle. The third generation of prosthesis is more conform to the characteristics of ankle biomechanics, with high postoperative survival rate and satisfactory clinical outcome.

CONCLUSION

At present, the survival rate of ankle prosthesis is low, and there is still much room for improvement in biomechanics, materials, and other aspects.

The Impact of α-Defensin Test in Diagnosing Periprosthetic Infection After Total Ankle Arthroplasty

Periprosthetic joint infection (PJI) after total ankle arthroplasty (TAA) is a serious complication, and a reliable diagnostic test to identify PJI is needed. The purpose of this study was to investigate the use of synovial α-defensin levels in identifying PJI of the ankle. Data from 33 patients were retrospectively collected between September 2015 and May 2018. Patients who had pain or suspected loosening after TAA and who had undergone joint aspiration were included in the study. Aspiration was performed in a semisterile theatre. Synovial fluid was processed in descending order for microbiological cultures, α-defensin, leukocyte esterase strip test, and cell count. A periprosthetic infection was defined by Musculoskeletal Infection Society criteria. The sensitivity, specificity, and overall accuracy were calculated, and based on a receiver operating characteristic curve, the quality of the α-defensin test was determined. The calculated area under the curve was 0.97 ± 0.32. Two of 33 patients fulfilled the 2014 Musculoskeletal Infection Society criteria and were scheduled for septic revision arthroplasty. Sensitivity, specificity, and overall accuracy of the α-defensin test were 100% (95% confidence interval [CI], 15.8% to 100%), 93.5% (95% CI, 78.6% to 99.2%), and 93.9% (95% CI, 79.8% to 99.3%), respectively. The positive predictive value was 50% (95% CI, 20.7% to 79.3%), and the negative predictive value was 100%. The α-defensin test seems to be the best available synovial test to detect a late-onset PJI after total ankle arthroplasty. Further prospective studies with a larger number of patients are required.

What Is the Treatment "Algorithm" for an Infected Total Ankle Arthroplasty (TAA)?

RECOMMENDATION

The treatment of an infected total ankle arthroplasty (TAA) is largely dictated by the acuity of the infection. The following treatment algorithm modified for TAA is recommended.¹⁹.

LEVEL OF EVIDENCE

Limited.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Conversion of painful tibiotalocalcaneal arthrodesis to total ankle replacement using a 3-component mobile bearing prosthesis

BACKGROUND

The aim of this study was to assess the short-term clinical and radiographic outcomes in patients who underwent conversion of a painful tibiotalocalcaneal arthrodesis to a total ankle replacement.

METHODS

Six patients with painful ankle arthrodesis after tibiotalocalcaneal arthrodesis were included in this study. In all patients, conversion to total ankle replacement was performed using a 3^rd-generation, non-constrained, cementless three-component prosthesis. The outcomes were analyzed at a mean follow-up of 3.4±1.9years (range 1.0-6.5).

RESULTS

One patient with painful arthrofibrosis underwent two open arthrolysis procedures at 1.2 and 5.6 years post index surgery, respectively. No revision of tibial or talar prosthesis components was necessary in this study. All patients reported significant pain relief and significant improvement in functional status.

CONCLUSION

In the present study, the conversion of a painful ankle arthrodesis following tibiotalocalcaneal arthrodesis to a total ankle replacement was a reliable surgical treatment.

Revision Surgery for Metal Component Failure in Total Ankle Arthroplasty

Background:

Metal component failure in total ankle arthroplasty (TAA) is difficult to treat. Traditionally, conversion to an arthrodesis has been advocated. Revision TAA surgery has become more common with availability of revision implants and refinement of bone-conserving primary implants. The goal of this study was to analyze the clinical results and patient-reported outcomes for patients undergoing revision total ankle arthroplasty.

Methods:

We retrospectively reviewed prospectively collected data on 52 patients with a mean age of 63.5 ± 9.6 years who had developed loosening or collapse of major metal components following primary TAA. These patients were compared to a case-matched control group of 52 primary TAAs performed at the host institution with a minimum of 2 years’ follow-up. Cases of isolated polyethylene exchange, infection, or extra-articular realignment procedures were excluded. The American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score, Short Form 36 (SF-36), Short Musculoskeletal Function Assessment (SMFA), and pain scores were prospectively collected. Clinical data was collected through review of the electronic medical record to identify reasons for clinical failure, where clinical failure was defined as second revision or conversion to arthrodesis or amputation.

Results:

The identified causes of failure of primary TAA were aseptic loosening of both components (42%), talar component subsidence/loosening (36%), coronal talar subluxation (12%), tibial loosening (8%), and talar malrotation (2%). Thirty-one patients (59.5%) underwent revision of all components, 20 (38.5%) just the talar and polyethylene components, and one (2%) the tibial and polyethylene components. The average time to revision was 5.5 years ± 5.4 with a follow-up of 3.1 years ± 1.5 after revision. Eleven (21.2%) revision arthroplasties required further surgery: 6 required conversion to arthrodesis and 5 required second revision TAA. Pain scores, SF-36 scores, SMFA scores, and AOFAS Hindfoot scores all improved after revision surgery but never reached the same degree of improvement seen after primary TAA.

Conclusions:

Clinical and patient-reported outcomes of revision ankle arthroplasty after metal component failure significantly improved after surgery, although the recovery time was longer. In this series, 21.2% of revision TAAs required a second revision TAA or arthrodesis surgery. Various prostheses performed similarly when used for revision surgery. Revision TAA can offer significant improvements postoperatively.

Level of Evidence:

Level III, therapeutic.

Patient-Reported Outcomes Before and After Primary and Revision Total Ankle Arthroplasty

BACKGROUND:

Studies examining the clinical outcomes of revision total ankle arthroplasty (TAA) are sparse. Revision TAA surgery has become more common with availability of revision implants and refinement of bone-conserving primary implants. In this study, patient-reported results and clinical outcomes were analyzed for a cohort of patients who underwent both primary and revision TAA at a single high-volume institution.

METHODS:

We retrospectively reviewed prospectively collected data on 29 patients with failed primary total ankle arthroplasty. Cases of isolated polyethylene exchange, infection, or extra-articular realignment procedures were excluded. Patient-reported outcome (PRO) measures and clinical results were reviewed in this longitudinal study.

RESULTS:

Fifteen patients (51.7%) underwent revision of just the talar and polyethylene components while 13 patients (44.8%) underwent revision of all components. The most common cause was talar subsidence (51.7%). The average time to revision was 3.9 years with a follow-up of 3.2 years after revision, and 3 (10.3%) revision arthroplasties required further surgery; 2 required conversion to arthrodesis and 1 required second revision TAA. Improvements in PROs were better after primary than revision TAA.

CONCLUSIONS:

Clinical and patient-reported results of revision ankle arthroplasty after metal component failure improved significantly but never reached the improvements seen after primary ankle arthroplasty. In our series, 10.3% of revision TAAs required a second revision TAA or arthrodesis surgery.

LEVELS OF EVIDENCE:

Therapeutic Level III, comparative series.

Sagittal Ankle and Midfoot Range of Motion Before and After Revision Total Ankle Replacement: A Retrospective Comparative Analysis

The most common reason for a revision total ankle replacement procedure is a painful, stiff ankle even after the initial surgery. Limited and conflicting data are available regarding the change in sagittal foot and ankle range of motion after revision total ankle replacement surgery. We sought to determine whether revision total ankle replacements would reduce compensatory midfoot range of motion. In determining this, a novel radiographic measurement system with stable osseous landmarks is used. A retrospective medical record review of patients who had undergone revision total ankle replacement from January 2009 to June 2016 was performed. Thirty-three patients (33 ankles) underwent revision total ankle replacement surgery and met the inclusion criteria with a mean follow-up period of 28.39 ± 14.68 (range 2 to 59) months. Investigation of preoperative and postoperative weightbearing lateral radiographic images was performed to determine the global foot and ankle, isolated ankle, and isolated midfoot sagittal ranges of motion. Statistical analysis revealed a significant increase in ankle range of motion (p = .046) and a significant decrease in midfoot range of motion (p < .001) from preoperatively to postoperatively. The change in global foot and ankle range of motion was not significant (p = .53). For this patient population, the increased ankle range of motion effectively resulted in less compensatory midfoot range of motion.

Trends in total ankle arthroplasty and revisions in the Medicare database

Background

High failure rates and unacceptable patient outcomes have kept total ankle arthroplasty (TAA) from becoming a favorable treatment option. Modern prosthetic designs and techniques have improved outcomes and decreased revision rates. Current literature has not adequately investigated the recent trends in TAA utilization and revision rate. The purpose of this study was to determine the trends in TAA utilization and the rate of revision TAA by analyzing a comprehensive Medicare database for procedures performed between 2005 and 2012.

Methods

A retrospective review of a comprehensive Medicare database within the PearlDiver Supercomputer application (Warsaw, IN) of the index procedures TAA and revision TAA was conducted. Patients who underwent TAA and revision TAA were identified by Current Procedural Terminology (CPT)-27702, 27703, and International Classification of Disease ninth revision (ICD) codes 81.56, 81.59 respectively. The primary outcomes of this study were annual revision incidence and TAA annual utilization. Demographic data such as age, gender, and geographical location of patients were also examined.

Results

Within our study period of 2005-2012 there was a reported total of 7,181 TAAs and 1,431 revision TAAs which is a revision incidence of 19.928% amongst the Medicare population. The compound annual growth rate (CAGR) was 16.37% for TAA, 7.74% for revision TAA, and a mean 7.41% annual revision incidence. Amongst females there were 3,568 TAA and 731 revision TAA compared with 3,336 TAA and 613 revision TAA amongst males. The greatest amount of TAA and revision TAA were found in the 65-69 age group followed by the 70-74 age group. Regionally, the highest number of TAA and revision TAA were found in the South and the lowest in the Northeast.

Conclusions

Our analysis of the Medicare database shows that there is a high rate of annual growth in TAA utilization (16.37%) and revision TAA (7.74%) indicating that there is an increased demand for TAA in the Unites States. However, failed TAA can have serious consequence and revision TAA remains to have suboptimal results. This study highlights the recent trends in ankle arthroplasty and serves to increase awareness of this increasingly popular procedure.

Can a Three-Component Prosthesis be Used for Conversion of Painful Ankle Arthrodesis to Total Ankle Replacement?

BACKGROUND

In patients with painful ankle arthrodesis, the surgical treatment is challenging, and may include takedown of ankle arthrodesis and conversion to a total ankle replacement (TAR). This procedure is technically demanding given the altered anatomy after arthrodesis. Few studies have evaluated TAR in the setting of prior arthrodesis.

QUESTIONS/PURPOSES

(1) What intraoperative and perioperative complications were observed in patients who underwent conversion of an ankle arthrodesis to a TAR? (2) Was durable fixation achieved at short term, and what was the alignment of the components? (3) What subsequent surgical procedures were performed, including revisions? (4) What improvements were observed in pain, tibiotalar range of motion (ROM), and quality of life?

METHODS

Between January 2007 and December 2014, 18 patients with a painful ankle arthrodesis underwent conversion to TAR at our tertiary referral center. During this period, the indications for conversion of ankle arthrodesis to TAR were tibiotalar nonunion or malunion after attempted arthrodesis in patients who declined revision ankle arthrodesis. The goal of revision surgery was to help patients regain hindfoot mobility and to decrease pain. During the study period, all patients who met indications were treated with a conversion procedure. Of the 18 patients included, 14 were men and four were women. The mean age of the patients was 51 ± 7 years. The mean followup was 54 ± 27 months, with no loss to follow up observed. The initial ankle arthrodesis was performed 6 ± 3.5 years before conversion to TAR. In all patients, the conversion to TAR was performed using a nonconstrained cementless three-component prosthesis. Intraoperative and postoperative complications, revision procedures, and prosthesis component loosening were evaluated. Weightbearing radiographs were used to determine the angular alignment of the tibial and talar components using α/β/γ angles and to analyze the bone-implant interface. Osseointegration was defined as visible trabecular structures at the bone-implant interface without radiolucent lines. The criteria for radiographic loosening was defined as subsidence or migration of prosthesis components and/or a cystic lesion with a diameter at least 2 mm. Clinical assessment included pain evaluation, measurement of ankle ROM, and quality of life.

RESULTS

Two of the 18 patients sustained an intraoperative medial malleolar fracture. In three patients, delayed wound healing was observed. At latest followup, four patients had incomplete osseointegration (posterior quarter of the bone-prosthesis interface on the tibial side). None of the 18 patients had prosthesis loosening. In all patients, both components were neutrally aligned. Two patients had painful arthrofibrosis with reduced ROM, which we treated with an open arthrolysis and exchange of mobile-bearing inlay; one other patient is considering a revision for substantial tibial component medial tilt with collapse of the medial arch. At the latest followup, the mean dorsiflexion and plantar flexion were 8.5° ± 3° and 15° ± 5°, respectively. The mean visual analog scale (VAS) score decreased from 9 ± 0.8 to 1.7 ± 1.6 (p < 0.001). The Short Form Health Survey questionnaire (SF-36) physical and mental outcome scores improved from 34 ± 5 to 74 ± 11 (p < 0.001) and from 49 ± 4 to 75.5 ± 7 (p < 0.001).

CONCLUSIONS

Conversion of an ankle arthrodesis to a TAR is a technically challenging procedure. In this small series, it was associated with frequent complications including arthrofibrosis, and functional outcomes including postoperative ROM were lower than reported for primary TAR. However, pain and function did improve. Further studies are necessary to address long-term clinical and radiographic outcomes in this patient cohort.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Current Update in Total Ankle Arthroplasty: Salvage of the Failed Total Ankle Arthroplasty with Anterior Translation of the Talus

Ankle replacement results may be compromised by malposition of the components. An anterior displacement can be measured on a lateral standing radiograph. The ankle may appear anteriorly translated because the ankle is overstuffed, the heel cord is tight, or the posterior capsule is tight. In ankle instability with degenerative arthritis, the talus may be anteriorly translated, internally rotated, and in varus. In an ankle replacement, this deformity may persist and will require correction. On occasion, the talus is inserted too anterior; revision to a flat cut talar component and posterior translation of the talar component will result in correction.

Revision of Stemmed Agility Implants

Total ankle arthroplasty has advanced rapidly in the last 20 years. Early agility implants enjoyed improved survivability compared with more archaic total ankle implants. When talar subsidence occurs, the revision options include a stemmed component to improve stability by spanning the subtalar joint. Removal and revision of these stemmed components can be difficult because of ingrowth and bone loss.

Dealing with the Stiff Ankle: Preoperative and Late Occurrence

In patients with a stiff ankle replacement, appropriate resection of scarred capsular structures, hypertrophic bone debridement, and careful release of tendons should be performed to achieve good outcomes. Appropriately sized and correctly implanted components are required to restore ankle function to as normal as possible. Although not proven, the better a total ankle replacement is balanced, the less likely scar and heterotopic bone formation will occur. In patients with a stiff and painful ankle replacement, a preoperative diagnostic workup is mandatory to understand the underlying pathologic process and plan appropriate treatment. All underlying causes should be addressed.

How To Diagnose and Treat Infection in Total Ankle Arthroplasty

Periprosthetic infection after total ankle arthroplasty (TAA) is a serious complication, often requiring revision surgery, including revision arthroplasty, conversion to ankle arthrodesis, or even amputation. Risk factors for periprosthetic ankle infection include prior surgery at the site of infection, low functional preoperative score, diabetes, and wound healing problems. The clinical presentation of patients with periprosthetic ankle joint infection can be variable and dependent on infection manifestation: acute versus chronic. The initial evaluation in patients with suspected periprosthetic joint infections should include blood tests: C-reactive protein and erythrocyte sedimentation rate. Joint aspiration and synovial fluid analysis can help confirm suspected periprosthetic ankle infection.

Identifying the learning curve for total ankle replacement using a mobile bearing prosthesis

BACKGROUND

Total ankle arthroplasty remains a technically demanding surgery highly influenced by the operator experience. However, no consensus exists regarding the ideal number of cases that need to be performed before a surgeon is considered proficient. The aim of this study was to identify the learning curve of a specific replacement system with regards to intraoperative and postoperative outcomes.

METHODS

The first 31 patients undergoing total ankle arthroplasty were examined. No additional procedures were performed at the time of the TAA. Intraoperative characteristics, postoperative complications, as well as clinical and radiologic outcomes were assessed with 24-month follow-up. Learning curves, examining the relationship between surgeon experience and patient outcomes, were determined using the Moving Average Method.

RESULTS

The operatory time, and the risk of intraoperative fractures decreased with increasing surgeon experience with the learning curve stabilizing after the 14th and 24th patient, respectively. Furthermore, there appeared to be a learning curve associated with most of the important clinical and radiological outcomes. The number of patients required to stabilize the learning curve for the VAS, ROM, and AOFAS was 11, 14 and 28, respectively. Radiographically, there appeared to be a learning curve of 22 patients required to stabilize the tibio-talar ratio. There was no learning curve associated with the SF-12 PCS and MCS as well as the α-, β-, and γ-angle.

CONCLUSION

This study demonstrates that a surgical learning curve does indeed exist when performing TAA. Most of the operative variables as well as clinical and radiological outcomes stabilize after a surgeon has performed 28 cases.

[Aseptic loosening of total ankle replacement : One-stage revision ankle arthroplasty]

OBJECTIVE

To revise one or both loosened prosthesis components, to achieve postoperative pain relief, and preserve ankle range of motion.

INDICATIONS

Aseptic loosening of the tibial and/or talar ankle prosthesis components without substantial bone defect of the tibial or talar bone stock.

CONTRAINDICATIONS

General surgical or anesthesiological risks, infections, critical soft tissue conditions, nonmanageable hindfoot instability, neurovascular impairment of the lower extremity, neuroarthropathy (e. g. Charcot arthropathy), substantial nonreconstructable osseous defects with or without cysts on the tibial and/or talar side, non-compliance, patients with primary total ankle replacement (TAR) using intramedullary fixation (stem fixation), patients with severely reduced bone quality, insulin-dependent diabetes mellitus, smoking, unrealistic patient expectations, patients with high activity in sports.

SURGICAL TECHNIQUE

Exposure of the ankle joint using the previous incision (anterior or lateral transfibular approach). Mobilization and removal of loosened prosthesis component. Careful debridement of bone stock at bone-prosthesis interface. Determination of prosthesis component size. Implantation of definitive prosthesis components. Wound closure in layers.

POSTOPERATIVE MANAGEMENT

A soft wound dressing is used. Thromboprophylaxis is recommended. Patient mobilization starts at postoperative day 1 with 15 kg partial weight bearing using a stabilizing walking boot or cast for 6 weeks. Following clinical and radiographic follow-up at 6 weeks, full weight bearing is initiated gradually.

RESULTS

Between January 2007 and December 2012 a one-stage revision TAR was performed in 14 patients with a mean age of 52.7 ± 12.0 years (29.8-70.5 years). The indication for revision surgery was aseptic loosening of one or both prosthesis components. The mean time between the initial TAR and revision surgery was 5.9 ± 2.9 years (2.0-11.5 years). In 2 patients a tibiotalocalcaneal arthrodesis was performed due to painful aseptic loosening of revision TAR. In all patients a significant pain relief was observed.

[Aseptic loosening of total ankle replacement and conversion to ankle arthrodesis]

OBJECTIVE

To remove loosened prosthesis components, to perform augmentation, to address osseous defects, to perform neutrally aligned ankle arthrodesis, and to achieve postoperative pain relief.

INDICATIONS

Symptomatic, aseptic loosening of total ankle replacement (TAR) with/without substantial bone defect of the tibial and/or talar bone stock.

CONTRAINDICATIONS

General surgical or anesthesiological risks, periprosthetic infection, local or systemic infection, nonmanageable soft tissue problems.

SURGICAL TECHNIQUE

Removal of both prosthesis components using the previous incision (mostly using anterior ankle approach). Careful debridement of bone stock at the tibial and talar side. Osseous augmentation of defects using autologous or homologous cancellous bone, if needed, using structural allografts.

POSTOPERATIVE MANAGEMENT

A soft wound dressing is used. Thromboprophylaxis is recommended. Patient mobilization starts on postoperative day 1 with 15 kg partial weight bearing using a stabilizing walking boot or cast for 6-8 weeks. Following clinical and radiographic follow-up at 6 weeks, full weight bearing is initiated gradually after progressive osseous healing has been confirmed.

RESULTS

Between January 2007 and December 2012, ankle arthrodesis was performed in 9 patients with failed TAR (6 men and 3 women, mean age 56.4 ± 7.0 years, range 47.8-66.0 years). The mean time between the initial TAR and revision surgery was 4.5 ± 2.4 years (range 1.2-7.9 years). In one patient irrigation and debridement was performed due to superficial wound infection. Another patient had a delayed osseous healing 11 months after the revision surgery.