Revision Total Ankle Replacement Research Articles

Lessons From Revision Total Ankle Replacement: Tibias Fail Earlier, and Taluses Fail Later (and Fail Again).

The literature on survivorship and outcomes after revision total ankle replacement (TAR) in the modern era is limited. This study aimed to describe the timing to revision and survivorship after revision TAR. We hypothesized that tibial-sided failures would occur earlier after the primary TAR, and secondary revisions after failure of revision TAR would occur more due to talar-sided failures than tibial-sided failures. This is a single-institution retrospective study of TAR patients with minimum 2-year follow-up. Revision TARs (defined as exchange of tibial and/or talar components) for aseptic causes with any implant were included. Etiology of failure necessitating revision and ultimate outcomes after revision (survival of TAR revision, additional revision, conversion to fusion, and below-knee amputation [BKA]) were recorded. There were 46 revision TARs, with mean age of 60.6 (range: 31-77) years and mean 3.5 years' follow-up postrevision. Revisions for tibial failure occurred significantly earlier (n = 22, 1.3 ± 0.5 years after index procedure) than those for talar failure (n = 19, 2.3 ± 1.7 years after index procedure) or combined tibial-talar failure (n = 5, 3.4 ± 3.4 years after index procedure) (P = .015). Revisions for tibial-only failure had better survival (95.5%) than revisions for talar or combined tibial-talar failures: 26% of talar failures and 20% of combined tibial-talar failures underwent ≥1 revisions. Of the 6 additional revisions after failure of the talar component, 1 ultimately underwent BKA, 2 were converted to total talus replacement, 2 were revised to modular augmented talar components, and 1 was treated with explant and cement spacer for PJI after the revision. TAR tibial failures occurred earlier than talar failures or combined tibial-talar failures. Revisions for talar failures and combined tibial-talar failures were more likely to require additional revision or ultimately fail revision treatment. This is important given the consequences of talar implant subsidence, bone necrosis, loss of bone stock, and limited salvage options. Level IV, case series.

OUTCOMES OF REVISION TOTAL ANKLE ARTHROPLASTY: A MINIMUM OF TWO-YEAR FOLLOW-UP

IntroductionTotal ankle replacement as a valid treatment for end stage ankle arthritis, is gaining popularity and every year there is an increasing number of procedures. With revision rates as high as 21% at 5 years and 43% at 10 years there is a need for understanding and reporting the outcome of revision ankle replacement. Our aim was to study the patient reported outcomes following revision TAR with a minimum of 2 year follow up.MethodsAll patients that underwent a revision total ankle replacement between 2012 and 2016 were included in the study. All patients received a post-operative questionnaire comprising of MOX-FQ score, EQ-5D (UK) and Foot and Ankle outcomes scores (FAOS) and patients satisfaction questionnaire with a minimum of 2 years follow up.Results33 patients had a revision total ankle replacement between 2012 and 2016. 2 patients were deceased therefore 31 patients were included in the study. 4 patients declined participation for completing questionnaires. We received 15/27 (55.5%) completed questionnaires. The mean MOX-FQ average domain score for pain was (50.6 ± 26.9), walking/standing (62.4 ± 36.5) and social function was (43.7± 31.0). The mean FAOS scores were (52.5 ± 30.6; pain), (54.5 ± 29.2; symptoms), (62.1 ± 30.5; ADL) and (35.5 ± 28.2; for quality of life). The mean overall health score today for EQ-5D was 73.9/100. 50% of patients were satisfied with the pain relief and return to sports and recreation obtained following the operation, 57% were satisfied with the improved in daily activities. 78.5% were overall satisfied with the results from surgery.ConclusionRevision total ankle replacement gives overall satisfactory results demonstrated from patients reported outcomes at a minimum of 2 years following surgery.

Lessons from Revision Total Ankle Replacement: Tibias Fail Early, and Taluses Fail Late (And Fail Again)

Introduction/Purpose: With the last decade’s surge in total ankle replacement (TAR), there is an anticipated commensurate increase in the number of revisions that orthopaedic foot and ankle surgeons will encounter. The salvage and implant options to deal with a failed primary TAR are expanding. However, the literature on survivorship and outcomes after revision TAR in the modern era is relatively limited. What’s more, little is known about the risk factors for further revision or failure of revision TAR. This study aimed to describe the timing to and survivorship after revision TAR. We hypothesized that tibial-sided failures would occur earlier after the index surgery, and secondary revisions after failure of revision TAR would occur more due to talar-sided failures than tibial-sided failures. Methods: This is a single-institution retrospective cohort study of TAR patients (2012-2022) with minimum 2-year follow-up. Revision TARs (defined as exchange of tibial and/or talar components) with any implant (Cadence, Inbone, Invision, Infinity, Salto, STAR, Vantage, Zimmer; or custom total talus replacement [TTR]) were included. Five surgeons contributed patients. Demographics, primary and revision surgical data, and postoperative complications were recorded. Etiology of failure necessitating revision (tibial failure, talus failure, combined failure) and ultimate outcomes after revision (revision TAR survived, additional revisions, conversion to fusion, below-knee-amputation [BKA]) were recorded. Revisions for periprosthetic joint infection (PJI) and conversions to fusion were excluded. There were 59 ankles that underwent revision for any cause. Excluding 9 2-stage revisions for PJI and 3 conversions to ankle or tibiotalocalcaneal fusion, there were 47 ankles that underwent revision TAR that were included for analysis. Chi-square and ANOVA tests were used to compare risk factors and timing for failure. Results: There were 47 revision TARs, with mean age 60.6 (range: 31-77) years, mean BMI 29.5 kg/m2, 19 (40.4%) females, and mean 3.5 years follow-up. Revisions for tibial failure (n=22) occurred significantly earlier (1.3 ± 0.5 years) than those for talus failure (n=19, 2.3 ± 1.7 years) or combined tibial/talus failure (n=6, 2.9 ± 3.3 years) (P=0.048). Revisions for tibial-only failure had significantly better survivorship (95.5%) than revisions for talus or combined tibia/talus failures: 26% of talus failures and 33% of combined tibia/talus failures underwent at least one more revision (P=0.033). Of the 7 failures after revision talus, 2 ultimately underwent BKA, 2 were converted to TTR, 2 were revised to modular stemmed talus implants, and 1 was treated with explant and cement spacer for PJI. Conclusion: This study demonstrates that TAR tibial failures occur earlier than talus failures or combined tibial/talus failures. When patients with isolated tibial failure undergo revision of both tibial and talar components, they usually do well with good survivorship post-revision. However, revisions for talar failures and combined tibial/talar failures occur later but are more devastating: nearly 1/3 go on to a second revision. This is important given the consequences of talar implant subsidence, bone necrosis, loss of bone stock, and limited salvage options. As TAR utilization expands, it is imperative to develop implants and surgical strategies to maximize success for revision surgery. Flowchart of failures after revision TAR. PJI = periprosthetic joint infection. TTC = tibiotalocalcaneal. BKA = below-knee amputation. Tibial implant geometry included: Low-pro = lowprofile tibial implant. Stem = stemmed tibial implant. Keel = keeled tibial implant. Talus implant geometry included: chamfer/round and flat-cuttalus.

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

BackgroundRevision 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. Methods19 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. ResultsThe 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). ConclusionCustom 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.

The Burden of Revision Total Ankle Replacement Has Markedly Increased from 2010 to 2020

Category: Ankle Arthritis Introduction/Purpose: Total ankle replacement (TAR) surgery has steadily increased in recent decades. The aim of the current study was to investigate the evolving burden of revision surgery and risk factors and timing of revision or implant removal. We hypothesized that there has been an increase in revision TAR and explant surgeries in the past decade and that younger age and higher comorbidity burden are risk factors for revision and explant. Methods: Using the 2010-2020 PearlDiver M151Ortho dataset, this retrospective cohort study identified primary TAR, TAR revision, and TAR explant patients. This is a large national database containing billing claims information on over 151 million patients in the United States across all payer types and sites of care. Patient factors investigated included age, sex, and Elixhauser Comorbidity Index (ECI, a longitudinal measure of patient comorbidity burden generated using ICD-9 and ICD-10 diagnosis codes). Annual incidence for primary and revision TAR, and explant were recorded. Multivariate logistic regression analyses were performed to determine independent risk factors for revision TAR or explant relative to primary TAR. For explants, the eventual intervention by two years was analyzed. Ten-year timing and survival to revision or explant surgery following patient-matched unilateral TAR were characterized. Results: Over the study period, there were 10,531 primary, 1,218 revision, and 1,735 explant TARs (increasing by 310%, 398%, and 9.6%, respectively). Independent predictors of revision TAR included: younger age (odds ratio [OR] 1.29 per decade decrease) and higher ECI (OR 1.23 per 2-point increase) (p < 0.0001 for both). Independent predictors of explant surgery included: younger age (OR 1.80 per decade decrease, p< 0.0001), female sex (OR 1.17, p=0.0011), and higher ECI (OR 1.35 per 2-point increase, p< 0.0001). Explanted patients went on to arthrodesis (37.7%), amputation (26.1%), revision TAR (14.7%), or no identified procedure/other procedures (21.5%) within the subsequent two years. The 10-year implant survival rate following primary TAR was 91.8%. 73% and 83% of revisions and explants occurred in the first three years following index TAR, respectively. Conclusion: The burden of TAR revision has grown substantially over the past decade. Younger age, female sex, and higher patient comorbidity burden were associated with increased risk of revision or explant surgery. If explant is pursued, most went on to arthrodesis or amputation. These results suggest that care should be taken in patient selection for TAR to minimize the occurrence of revision and explant surgery. Treatment algorithms should be modified to optimize outcomes among patients who undergo explant or revision surgery.

Early Survivorship, Clinical and Radiographic Outcomes Following Primary and Revision Total Ankle Arthroplasty using a Modular Augmented Revision (INVISION) Implant

Category: Ankle Arthritis; Ankle Introduction/Purpose: As the number of total ankle replacements (TAR) performed annually increases, there is an increased demand for implants that can be used in revision scenarios when primary TARs fail. As indications for TAR expand, there is increased reliance on modular systems to treat challenging conditions including bone loss, avascular necrosis, and instability. The INVISION Total Ankle Arthroplasty System (Wright Medical Technology/Stryker, Memphis, TN), released in 2018, includes modular augmented tibial trays and talar plates of varied heights to compensate for bone loss. There is limited data on early survivorship and clinical outcomes of the INVISION. This novel study aims to determine the early implant survivorship, complications, patient-reported outcomes (PROMIS), and radiographic outcomes of the INVISION implant used in both the primary and revision arthroplasty setting. Methods: This study is a single-institution retrospective review of adult patients who underwent primary or revision TAR with the INVISION implant with minimum 2-year follow-up. Demographics, reason for use of INVISION, surgical data, complications, pre- operative and 2 year post-operative radiographic data, and pre-operative and 2-year post-operative patient-reported outcome scores were collected. The primary outcome was survivorship (retention of both tibial/talar components at final follow-up). Secondary outcomes were reoperation (return to OR with retention of both tibial and talar components), radiographic complications (peri-implant lucency, cysts, or subsidence), and patient-reported outcomes (PROMIS pre-operative and 2-year post-operative). PROMIS scores were collected across the following domains: physical function, pain interference, pain intensity, global mental health, and depression score. Results: Twenty-six patients (primary=7; revision=19) underwent INVISION TAR (mean age 62 years, weight 81.kg, BMI 29.3 kg/m2, 15/26 male) with mean follow-up 3.5 years. Reason for INVISION primary TAR included tibial (n=1) or talar (n=5) bone loss, and take-down fusion (n=1); INVISION revision TAR was used for tibial (n=6) or talar (n=7) component subsidence, recurrent tibiotalar malalignment (valgus=1, varus=3), and post-infection bone loss (n=2). Two-year implant survivorship was 100%. There were 2 reoperations (7.7%): 1 gutter debridement and 1 irrigation, debridement and polyethylene exchange for infection. Two-year follow-up PROMIS domains improved significantly (p < 0.05) from pre-operative in both the primary (pain interference, pain intensity) and revision cohorts (pain interference, pain intensity, global physical function). Two-year radiographic follow-up yielded 1 tibial peri-implant lucency and 1 tibial cyst. Conclusion: In this single-institution series, there was excellent short-term survivorship of the INVISION TAR implant with no failures in primary or revision cases. There were significant improvements in patient-reported outcomes scores. There were low rates of peri-implant lucencies and cysts. The results of this study support the use of the INVISION implant in both the complex primary and revision TAR setting. INVISION may offer an alternate surgical solution to fusion, custom printed cage implants, and total talus replacement in this complex patient population. Further research and follow-up data are warranted to report the longer-term outcomes and survivorship of this implant.

The Burden of Revision Total Ankle Replacement Has Increased From 2010 to 2020.

Total ankle replacement (TAR) surgery has increased in recent decades. The aim of this study was to investigate the evolving burden of revision surgery and risk factors and timing of revision or explant. Using the 2010 to 2020 PearlDiver M151Ortho data set, this retrospective cohort study identified primary TAR, TAR revision, and TAR explant patients via Current Procedural Terminology (CPT) and International Classification of Disease Procedural (ICD-P) codes. This database contains billing claims information across all payers and sites of care in the United States. Patient factors investigated included age, sex, and Elixhauser Comorbidity Index (ECI). Annual incidence for primary TAR was normalized per 100 000 covered lives in the data set for each year of study and recorded. Annual incidence of revision TAR and explant were normalized per 100 TARs performed for each year of study. Multivariate logistic regression analyses were performed to determine independent risk factors for revision TAR or explant. For explants, the eventual intervention by 2 years was analyzed. Ten-year timing and survival to revision or explant surgery following unilateral TAR were characterized. A total of 10 531 primary, 1218 revision, and 1735 explant TARs were identified. After normalization, TAR utilization increased by 284% from 2010 to 2020, annual TAR revisions rose 28%, and annual TAR explants decreased 65%. Independent predictors of revision TAR were younger age (odds ratio [OR] 1.29 per decade decrease) and higher ECI (OR 1.23 per 2-point increase). Independent predictors of explant included younger age (OR 1.80 per decade decrease), female sex (OR 1.17), and higher ECI (OR 1.35 per 2-point increase). The 10-year implant survival rate was 91.8%, of which 73% of revisions and 83% of explants occurred in the first 3 years following index TAR. TAR utilization has grown substantially over the past decade, with minimal increases in the annual rate of revision surgery with respect to index procedures performed. Level III, retrospective cohort study.

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.

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. 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? 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. 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). 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 IV, therapeutic study.

Tibiopedal Motion Following Tendo-Achilles Lengthening or Gastrocnemius Recession in Total Ankle Replacement: A Comparative Cohort Study.

End-stage ankle arthritis is a debilitating condition often necessitating total ankle replacement (TAR). Tendo-Achilles lengthening (TAL) and gastrocnemius recession (GR) are commonly performed with TAR to improve ankle dorsiflexion (DF). No studies to date have radiographically analyzed tibiopedal motion to guide surgical management. The purpose of this study is to determine the effect of a TAL or GR during TAR on radiographic tibiopedal range of motion (ROM). A retrospective review of a prospectively maintained database was conducted followed by a propensity score-matched analysis of 110 patients who underwent TAL (n = 26), GR (n = 29), or no lengthening procedure (n = 55) with TAR. Minimum of 1-year ROM radiographic follow-up was required. Exclusion criteria included (1) calcaneal osteotomies, (2) simultaneous or previous hindfoot or midfoot arthrodesis, (3) prior ankle arthrodesis, or (4) revision TAR. Demographic data were extracted from the TAR database. Radiographic assessment included tibiopedal dorsiflexion (DF) and plantarflexion (PF). DF improved by 2.8 degrees (P = .0286) and by 6.0 degrees (P < .0001) in the TAL and GR cohorts, respectively, with no difference in the control group (+0.7 degrees, P = .3764). PF was decreased by 4.5 degrees (P = .0152) and by 7.2 degrees (P = .0002) in the TAL and GR cohorts, respectively, with no difference in the control group (-0.2 degrees, P = .8546). Minimal differences were observed for total arc of motion for all 3 groups (control 0.5 degrees, GR -1.2 degrees, TAL -1.7 degrees), all of which were nonsignificant (all P > .05). There was no between-group difference in the change in overall arc of motion between the groups (P = .3599). GR resulted in a greater increase in DF (6.0 vs 2.8 degrees; P = .1074), with a reciprocal greater decrease in PF (7.2 vs 4.5 degrees; P = .2416) compared with the TAL cohort. Both TAL and GR increased postoperative DF; however, this was accompanied by a reciprocal loss in PF. Minimal differences were observed for total arc of motion. Patients should be counseled that concomitant procedures performed to increase DF will do so at the expense of PF. Level III, retrospective review of prospectively collected data.

Short-Term Outcomes of a Two-Component Total Ankle Replacement in Revision Arthroplasty

Category: Ankle Arthritis; Ankle; Hindfoot Introduction/Purpose: Given the growing number of primary total ankle replacements (TAR), an increase in the numbers of failed ankles and consecutive revisions might be expected. Achieving a stable and balanced ankle based on stable components while preserving the remaining bone stock as much as possible, are crucial for success in revision TAR. Most reported techniques rely on bulky implants with extended fixation features. Since 2018, we have used a novel 3-component ankle for revision surgery that is converted in situ to a fixed-bearing 2-component ankle once the components have found their position given by the individual anatomy. The purpose of this study was to determine the short-term results of this novel concept in revision TAR. Methods: This single-center retrospective cohort study included 57 patients (57 ankles, mean age 63+-13 years) treated for failed TAR with the semi-constrained HINTERMANN Series H2© (H2) implant between February 2018 and February 2020. Survival analysis was performed and potential risk factors using Cox regression, were assessed. Clinical and radiological outcomes were assessed preoperatively and at the last follow-up. Clinical outcomes included pain on a visual analog scale (VAS), the American Orthopaedic Foot &amp; Ankle Society (AOFAS) ankle hindfoot score and patient satisfaction. Radiological outcomes were tibial articular surface angle (TAS), tibiotalar surface angle (TTS), talar tilt angle (TT) in the coronal plane and anteroposterior offset (AP-Offset) ratio in the sagittal plane, as well as signs of radiolucency and/or loosening on plane weightbearing radiographs. Results: The median follow-up was 2 (2.0 to 4.0) years. The cumulative incidence for secondary revision after 1 and 2 years was 5.1% (95%CI 0-11) and 7.4% (0-14) respectively. Four patients needed a secondary revision (three for pain/arthrofibrosis and one for aseptic loosening). While the AOFAS hindfoot score increased from median 54 (range 9-94) to 75 (19-98) (p=0.00001), satisfaction increased from moderate to good (p=0.0017). Radiographically, all components were stable without signs of increased shear-forces in terms of loosening or radiolucency. Conclusion: Obtained results with the novel customized semi-constrained total ankle implant design at short-term are encouraging, with a satisfactory survival rate and acceptable revision rate. The fixation concept without extended fixation features was shown to last against increased shear forces.

Reconstruction of Severe Osteolytic Malleoli using Femoral Head Allograft in a Revision Total Ankle Replacement: A Case Report

Category: Ankle Arthritis; Ankle; Hindfoot Introduction/Purpose: Case: A 38-year-old male patient presented with severe pain in the left ankle who underwent a total ankle replacement (TAR) and syndesmotic fusion for end-stage ankle osteoarthritis (OA) 13 years ago. Radiographic evaluation showed implant loosening and extensive osteolytic lesion of both malleoli. Revision was performed using a three-component TAR system and reconstruction of the malleoli with femoral head allograft. Methods: N/A Results: N/A Conclusion: Reconstruction of severe osteolytic lesions of the malleoli with femoral head allograft in the setting of revision TAR allowed to create a stable bone stock, implant anchorage, desirable stability and therefore maintaining joint function.

Risk Factors for Early Mechanical Failure and Revision in Modern Total Ankle Replacements

Category: Ankle Arthritis; Ankle Introduction/Purpose: Total ankle replacements (TAR) have rapidly advanced in terms of volume, technique, design, and indications. However, they are still at risk for failure and need for revision, even early in the postoperative period. Although recently there has been extensive research on TAR, many studies are limited in their power and sample size to assess risk factors for failure/revision. Using a large multi-surgeon retrospective database, we sought to describe the incidence and etiology of mechanical failure across modern implants. We also aimed to identify risk factors for early mechanical failure. We hypothesized that greater body mass index (BMI) and ipsilateral hindfoot fusion would be predictors of mechanical failure, and that implants with greater extent of tibial fixation (stems and keels) would be protective against mechanical failure. Methods: This is a single-center retrospective review of TAR patients in a prospective database. Adults undergoing primary TAR using any implant (Cadence, Inbone, Infinity, Invision, Salto, STAR, Vantage, Zimmer) who were minimum 2 years post-surgery were included. Exclusion criteria included revision TAR or patients undergoing ankle fusion takedown and conversion to TAR. Five surgeons contributed patients. Demographics, etiology of arthritis, operative data, and postoperative complications, reoperations, and revisions were collected. Revisions and reoperations were classified by standard criteria. Cause of revision was recorded. There were 560 TARs eligible for 2-year follow-up (mean 3.9 +- 1.1 years postoperative), with mean follow-up of 2.2 +- 1.4 years (range 1-71 months). The cohort had mean age 63.8 +- 9.1 years, BMI 29.4 +- 5.2 kg/m2, and 57% were male. Kaplan- Meier survival plots were created. Risk factors for revision due to mechanical failure were analyzed using multivariable logistic regression with partial Wald chi square statistics. Results: Most implants were low-profile (n=444, 79.3%), with 28 implants having tibial keels (5%) and 88 with tibial/talar stems (15.7%). There were 25 (4.5%) revisions of tibial and/or talar components at mean 1.6 years after index surgery (Figure). Preoperative coronal deformity did not impact revision rates (p=0.433). Patients who underwent revision for mechanical failure had significantly higher rates of concomitant hindfoot fusion (20% vs. 8.4%, p=0.047) and greater BMI (31.4 kg/m2 vs. 29.3 kg/m2, p=0.04). In multivariable logistic regression, hindfoot fusion was just short of statistical significance (odds ratio [OR] 2.96, p=0.056), and BMI was not significant (OR 1.05, p=0.417). Stemmed or keeled implants did not significantly decrease revision rates compared to low-profile implants, although the revision rate of stemmed implants was substantially low (1/88, 1.1%). Conclusion: Among 560 modern TAR implants, short-term survivorship was 95% at 2-year follow-up, which is consistent with existing studies. Patients who underwent revision for early mechanical failure had significantly higher BMI and rates of hindfoot arthrodesis. However, these variables fell short of statistical significance in multivariable regression, suggesting that there are either additional factors contributing to revision, or a larger cohort is needed. In addition, these results are likely biased by surgeons' tendencies to use stemmed implants in patients with hindfoot fusions. Further research is warranted to determine if stemmed implants provide a protective effect in these high-risk patients.

INBONE Revision Total Ankle Arthroplasty

The INBONE total ankle replacement is both a primary and a revision total ankle replacement. It is a modular tibial ankle with the ability to increase the length of the stem as necessary for stability. It also has available an enlarged baseplate for the tibia and a modular talar extension component for use when the talar bone is insufficient for the standard prosthesis. Its flexibility in use makes it an ideal ankle replacement for revision ankle replacement surgery.

Outcomes of Revision Total Ankle Replacement: A Minimum of 2 Year Follow-up

Category:Ankle, Ankle ArthritisIntroduction/Purpose:Total ankle replacement as a valid treatment for end stage ankle arthritis, is gaining popularity and every year there is an increasing number of procedures. With revision rates as high as 21% at 5 years and 43% at 10 years there is a need for understanding and reporting the outcome of revision ankle replacement. Our aim was to study the patient reported outcomes following revision TAR with a minimum of 2 year follow up.Methods:All patients that underwent a revision total ankle replacement between 2012 and 2016 were included in the study. All patients received a post-operative questionnaire comprising of MOX-FQ score, EQ-5D (UK) and Foot and Ankle outcomes scores (FAOS) and patients satisfaction questionnaire with a minimum of 2 years follow up.Results:32 patients had a revision total ankle replacement between 2012 and 2016. 2 patients were deceased therefore 30 patients were included in the study. 5 patients declined participation for completing questionnaires. We received 21 (66%) completed questionnaires. The mean MOX-FQ average domain score for pain was 58.8, walking/standing 65.8 and social function was 48.2. The mean FAOS scores were 50.7 for pain, 50.6 for symptoms, 54.9 for ADL and 28.2 for quality of life. The mean overall health score today for EQ-5D was 67.8/100. 45% of patients were satisfied with the pain relief and return to sports and recreation obtained following the operation, 48% were satisfied with the improved in daily activities. 52% were overall satisfied with the results from surgery.Conclusion:Revision total ankle replacement gives overall satisfactory results demonstrated from patients reported outcomes at a minimum of 2 years following surgery.

The Effect of Exchanging a Mobile-Bearing into a Fixed-Bearing Total Ankle Replacement System in Patients with Coronal Plane Instability

Category:Ankle, Ankle ArthritisIntroduction/Purpose:The interface between the polyethylene (PE) inlay and the tibial component in mobile-bearing total ankle replacement (TAR) systems may allow the talus to seek its position according to the individual anatomy. However, chronic overload and/or incompetence of soft tissue may allow medial and/ or lateral translation of the talar component over time. This typically results in medial and/ or lateral gutter pain as well as pain along the syndesmosis. The purpose of this study was to assess the effect of tibial component exchange and conversion from a mobile-bearing into a fixed-bearing TAR system in patients with coronal plane instabilities TAR.Methods:A consecutive series of 30 ankles (29 patients; age 65.6 [48.9 – 86.1]; male, 23; female, 7) with coronal plane instabilities underwent revision TAR with exchange of a mobile-bearing (Hintermann Series, H3) into a fixed-bearing (Hintermann Series, H2) TAR system. Patients presented with a medial (n = 12) or lateral (n = 9) translation of the talar component, or a varus (n = 4) or valgus (n = 5) instability with subsequent tilt of the talar component. After removing the tibial component and PE inlay, a tibial osteotomy was performed and 1 to 2 mm of the distal tibia removed. A tibial component of the H2 total ankle system was inserted. While holding the foot in neutral position, the PE inlay was locked to the tibial component in the appropriate position. Functional outcome and pain were recorded to evaluate clinical outcome, and standard radiographs under fluoroscopy were taken for radiographic assessment.Results:All but one of the remaining 28 patient showed significant improvement of pain (P<0.05). Preoperative gutter pain disappeared completely in 20 ankles (71.4%), and partially in 8 ankles (18.6%). The AOFAS Hindfoot Score improved from 54.3 (range, 21 to 90) preoperatively to 74.0 (range, 48 to 92) at latest follow-up (P<0.05). Radiographic assessment showed firm osteointegration in all patients with the talar component centralized in the ankle mortise, and a free medial and lateral gutter without tilt of talar component (Figure 1). One patient with bilateral revision TAR was affected by a bilateral deep infection of both ankles 9 months after surgery subsequent to a severe pneumonia. Both ankles were removed and replaced by a cement spacer.Conclusion:Converting a mobile-bearing into a fixed-bearing TAR system has shown to be effective in the treatment of patients with coronal plane instabilities following TAR. Allowing the PE inlay to adapt its position according to the talar component before definitive fixation to the tibial component of the H2 series, saved having to replace the talar component. Future long-term studies however are needed to identify significant benefits of this novel total ankle concept in primary and revision TAR.

Restoration of Talar Height using a Modular Revision Prosthesis after Failed Total Ankle Arthroplasty

Category:AnkleIntroduction/Purpose:Talar component subsidence is the most common indication for revision total ankle replacement. The management of talar bone loss and alteration in the ankle joint center of rotation is challenging following component subsidence. Unfortunately, ankle arthrodesis as a salvage procedure for failed ankle arthroplasty has been associated with high rates of nonunion and collapse. Equally unfortunate, there is paucity in the literature on revision total ankle arthroplasty. The purpose of this study was to report the early outcomes of revision total ankle replacement using a modular prosthesis and metal/cement augmentation to reconstitute talar height following catastrophic failure of the index total ankle arthroplasty.Methods:Retrospective review was performed on sixteen patients who underwent revision total ankle replacement for failed arthroplasty associated with talar component subsidence and subsequent talar bone loss. All patients underwent revision arthroplasty using a revision modular ankle prosthesis and had a minimum of one-year follow-up. Demographic data, postoperative complications, original prosthesis, and concomitant procedures were recorded. Radiographic measurements were performed at three time-points (preoperative, immediately after surgery, and at most recent follow-up) to evaluate alignment of the prosthesis, talar height, and ankle range of motion. Implant survivorship was determined. Failure was defined as >2 mm of talar subsidence, conversion to ankle arthrodesis or below the knee amputation, and/or revision of the prosthesis. Ankle Osteoarthritis Score (AOS), Foot Function Index (FFI), and visual analog score (VAS) were collected at the most recent postoperative visit.Results:Patient follow-up ranged from 12.1 –20.6 months, with a mean follow-up of 15.0 months. The mean preoperative and immediate postoperative talar height was 28.7 mm and 33.4 mm, respectively. There was a significant improvement in talar height of 4.7 mm after revision total ankle replacement (P<0.001). Talar height was maintained at most recent follow-up. The mean preoperative and postoperative radiographic arc of motion was 19.5° and 24.0°, respectively. Two patients, with a mean BMI of 43.5, developed >2 mm of talar subsidence (one patient required revision surgery). The mean postoperative AOS and FFI was 25.0 and 28.8, respectively. The majority of patients (84%) were satisfied with their outcome, and all patients would choose to undergo the same procedure again (vs. arthrodesis or amputation).Conclusion:Revision ankle replacement using a modular prosthesis with metal/cement augmentation allows restoration of talar height. Though we recognize this data constitutes a very early follow up, this cohort has utilized the revision ankle implant with significant repetitive load after which older generation implants underwent secondary subsidence due to poor talar bone stock. Early outcomes demonstrate a predictable method to salvage catastrophic prosthesis failure associated with severe talar subsidence and deformity. The risk of postoperative complications, although moderate, is an acceptable alternative to lower limb amputation/arthrodesis. Further follow-up is warranted to determine functional outcomes and longevity of revision implant systems.

Algorithm for Management of Periprosthetic Ankle Fractures.

Evidence on the management of and outcomes from periprosthetic fractures about a total ankle replacement (TAR) are limited. The purpose of this study was to develop an algorithm for the management of patients with postoperative periprosthetic fractures about a TAR. This was a retrospective analysis of patients undergoing a TAR from 2007 through 2017 with a subsequent periprosthetic fracture >4 weeks from index surgery. Implant stability was defined radiographically and intraoperatively where appropriate. Univariate and multivariate analyses were used to identify differences in outcomes. Thirty-two patients were identified with a remote TAR periprosthetic fracture with an average follow-up of 26 months (range, 3-104 months). Most fractures were located about the medial malleolus (62.5%); the majority of fractures (75%) were deemed to have stable implants. Fractures of the talus always had unstable implants and always required revision TAR surgery (100%, P = .0002). There was no difference in patient-reported outcomes between stable and unstable fractures at an average of 36 months. In a multivariate analysis, fracture location (talus), less time to fracture, and implant type were found to be predictive of unstable implants ( P < .001). Implant stability was independently associated with the need for revision surgery ( P < .049). Nonoperative treatment was independently associated with treatment failure ( P < .001). The majority of stable fractures about a TAR required operative fixation. Management with immobilization was fraught with a high rate of subsequent surgical intervention. We found that fractures about the talus required revision TAR surgery or arthrodesis. Level III, retrospective cohort study.

Restoration of Talar Height using a Modular Revision Prosthesis after Failed Total Ankle Arthroplasty

Category: Ankle Arthritis Introduction/Purpose: Talar component subsidence is the most common indication for revision total ankle replacement. The management of talar bone loss and alteration in the ankle joint center of rotation is challenging following component subsidence. Unfortunately, ankle arthrodesis as a salvage procedure for failed ankle arthroplasty has been associated with high rates of nonunion and collapse. Equally unfortunate, there is paucity in the literature on revision total ankle arthroplasty. The purpose of this study was to report the early outcomes of revision total ankle replacement using a modular prosthesis and metal/cement augmentation to reconstitute talar height following catastrophic failure of the index total ankle arthroplasty. Methods: A retrospective review was performed on sixteen patients who underwent revision total ankle replacement for failed arthroplasty associated with talar component subsidence and subsequent talar bone loss. Demographic data, postoperative complications, index implant, and concomitant procedures were recorded. Radiographic measurements were performed at three time-points (preoperative, immediately postoperative, and most recent follow-up) to evaluate alignment of the prosthesis, talar height restoration, and range of motion. Results: Patient follow-up ranged from 9.3 –19.1 months, with a mean follow-up period of 12.2 months. The maximum preoperative and postoperative talar coronal misalignment was 16.2° and 3.5°, respectively. The mean preoperative and immediate postoperative talar height was 28.7 mm and 33.3 mm, respectively. There was a significant improvement in talar height of 4.6 mm after revision total ankle replacement (P&lt;0.001). There was no difference in talar height between the immediate postoperative visit and latest follow-up visit (33.2 mm). The mean preoperative and postoperative radiographic arc of motion was 19.5° and 24.0°, respectively. Ten patients (62.5%) did not sustain complications post surgical. Three patients developed a superficial wound complication that healed without additional surgery. One patient required a transmetatarsal amputation. Other complications included neuritis and DVT. Conclusion: Revision ankle replacement using a modular prosthesis with metal/cement augmentation allows restoration of talar height. Though we recognize this data constitutes a very early follow up, this cohort has utilized the revision ankle implant with significant repetitive load after which older generation implants underwent secondary subsidence due to poor talar bone stock. Early outcomes demonstrate a predictable method to salvage catastrophic prosthesis failure associated with severe talar subsidence and deformity. The risk of postoperative complications, although moderate, is an acceptable alternative to lower limb amputation/arthrodesis. Further follow up is warranted to determine functional outcomes and longevity of revision implant systems.

Syndesmotic Instability After Total Ankle Replacement

Category: Ankle Arthritis Introduction/Purpose: Total ankle replacement (TAR) evolved over the last decades and has been shown to be an effective concept in the treatment of ankle osteoarthritis (OA). In three-component designs, the second interface between polyethylene insert (PI) and tibial component allows the PI to find its position according the individual physiological properties. This was believed to decrease shear forces within the ankle joint. However, it is not clarified to which extent such an additional degree of freedom may overload the ligamentous structures of the ankle joint over time. This may in particular be the case for the syndesmotic ligaments. Therefore, the purpose of this study was to analyze all ankles after TAR that showed a symptomatic overload of the syndesmotic ligaments and to determine the potential consequences. Methods: Between 2003 and 2017, 31 ankles (females, 17; males 14; mean age 60 [40-79] years) were treated with a tibio-fibular fusion for a symptomatic instability of the syndesmosis. The indication for TAR was posttraumatic OA in 27 (87%), primary OA in 3 (10%), and hemochromatosis in one ankle (3%). The 31 ankles included 23 primary TAR (74%), 6 revision TAR (19%), and two take-down of a fusion and conversion to TAR (7%). Criteria for fusion were the presence of at least two of the followings: (1) tenderness over the syndesmosis, (2) pain while compressing the fibula against the tibia (squeeze test), (3) pain while rotating the foot externally (external rotation test), (4) widening of the syndesmosis on an anteroposterior view. Alignment of TAR (tibial articular surface [TAS] angle) and hindfoot alignment were measured on standard radiographs. Intraoperatively, the syndesmotic instability was confirmed before fusion. The wear of PI was documented. Results: After a mean of 63 (range, 4 – 152) months after TAR, all patients evidenced pain at the level of the syndesmosis of at least 3 months. 25 ankles (81%; 24 after posttraumatic OA) showed a widening of the syndesmotic space and 22 ankles (71%) of the medial clear space with lateral translation of the talus. The PI was seen to overlap the tibial component in 15 ankles (48%). Nine ankles (29%) evidenced cyst formation, and eight ankles (26%) showed a decrease in height of the PI; whereas, in 3 ankles (10%) a fracture of the PI was found. A valgus misalignment of the heel was found in 25 ankles (81%), a valgus TAS in 16 (52%) and a varus TAS in 11 ankles (36%). Conclusion: A syndesmotic instability after a three-component TAR apparently occurred mostly after posttraumatic OA, in particular if the heel was left in valgus. If the talus starts to move lateralward, the PI seems to be at risk for increased wear and finally mechanical failure (Figure 1). Therefore, a valgus misaligned heel should always be corrected during TAR implantation. If there is any sign of syndesmotic instability, a fusion should be considered. Further studies must proof whether in cases with a syndesmotic instability the use of a two-component design will be superior, as it stabilizes the talus in the coronal plane.

Periprosthetic Ankle Fractures

Category: Ankle Introduction/Purpose: Total ankle replacements (TAR) are an increasingly popular option for the management of tibiotalar arthritis. Periprosthetic fracture is an uncommon but challenging complication of patients undergoing arthroplasty. Evidence on the management of and outcomes from periprosthetic fractures about a TAR are limited. The purpose of this study was to evaluate patients with postoperative periprosthetic fractures about a TAR and determine clinical outcomes of these patients following operative fixation. Additionally, we propose an algorithm for the management of these patients. Methods: We retrospectively analyzed 400 patients who underwent TAR from 2007 through 2017. Charts were reviewed and patients with postoperative fractures were selected for inclusion. Patients with a fracture &gt;4 weeks from index surgery were considered candidates for inclusion. Patients with intraoperative fractures were excluded. Univariate analyses were used to identify differences in outcomes. Results: 32 patients were identified with a postoperative periprosthetic fracture about a TAR. Average age was 65.3 years. Average time to fracture was 39.5 months while average follow up from fracture was 26 months. Fractures were primarily located about the medial malleolus (60.6%). 76.8% of fractures were deemed to be stable (Table 1); 75% of these fractures were managed with ORIF or IMN, while 21% of these fractures were treated with immobilization. 80% of patients with stable fractures treated with immobilization ultimately required surgical intervention. 24.2% of fractures were deemed to be unstable. Fractures about the talus were always unstable and always required revision TAR surgery (100%, p= 0.0002). Conclusion: This retrospective review demonstrates that the majority of periprosthetic fractures about a TAR involve the medial malleolus. Additionally, the majority of stable fractures about a TAR required operative fixation. Despite attempts at nonoperative management, management with immobilization is fraught with a high rate of subsequent surgical intervention. Fractures about the talus should be treated with revision TAR surgery or arthrodesis. Based on these findings, we propose an algorithm for the management of patients with a periprosthetic fracture about a TAR.