Malalignment is often postulated as the main reason for the high failure rate of total ankle replacements (TARs). Only a few studies have been performed to correlate radiographic TAR malalignment to the clinical outcome, but no consistent trends between TAR alignment parameters and the clinical outcome were found. No standard TAR alignment measurement method is present, so reliable comparison between studies is difficult. Standardizing TAR alignment measurements and increasing measurable parameters on radiographs in the clinic might lead to a better insight into the correlation between malalignment and the clinical outcome. This study aims to develop and validate a tool to semi-automatic measure TAR alignment, and to improve alignment measurement on radiographs in the clinic. A tool to semi-automatically measure TAR alignment on anteroposterior and lateral radiographs was developed and used by two observers to measure TAR alignment parameters of ten patients. The Intraclass Coefficient (ICC) was calculated and accuracy was compared to the manual measurement method commonly used in the clinic. The tool showed an accuracy of 76% compared to 71% for the method used during follow-up in the clinic. ICC values were 0.94 (p<0.01) and higher for both inter-and intra-observer reliability. The tool presents an accurate, consistent, and reliable method to measure TAR alignment parameters. Three-dimensional alignment parameters are obtained from two-dimensional radiographs, and as the tool can be applied to any TAR design, it offers a valuable addition in the clinic and for research purposes

Introduction:. Ankle arthritis is a leading cause of pain and disability. The effect of this condition on physical and mental health is similar to end stage hip arthritis. There is paucity of literature on PROMS following total ankle replacements (TAR) in comparison to total hip replacement (THR) or knee replacement (TKR). We aimed to study 5 year outcomes of TAR in comparison with TKR and THR. Methods:. PROMS data from patients who underwent a primary THR, TKR or TAR from March 2003 to 2013 were collected from our hospital patient registry. They were divided into 3 groups based on the type of primary joint replacement. Patient demographics and patient reported outcomes (WOMAC, SF-36 scores and patient satisfaction scores at follow up) were compared at pre-op and 5 year follow up. Results:. There was data available on 1920 THR, 2582 TKR and 248 TAR patients. Pre-operatively, TAR patients reported higher function scores when compared to THR and TKR (40.2 vs. 34.2 and 35.8; p<0.05). For SF-36 scores, there was no difference between groups for general health, role emotional components (P>0.05); TAR patients reported similar scores to TKRs for physical domains; to THRs for the mental domains (P>0.05). At 5 years post-op, TARs reported lower scores than THRs and TKRs for function and stiffness. For SF-36 scores, TARs reported similar outcomes to THR and TKR for mental health components (p>0.05), similar scores to TKR for 3/4 physical domains (p<0.05), but lower satisfaction rates for ADL and recreation when compared to THR (P<0.05). Conclusion:. TAR patients had similar outcomes to THR or TKR patients for disease specific and mental health domains, and lower patient satisfaction rates in terms of pain relief, ADL and recreation. Further research is warranted including clinical outcomes along with PROMS with a long term follow up

Purpose. Total Ankle Replacement (TAR) is increasingly being offered to patients as an alternative to arthrodesis for the operative management of debilitating end-stage ankle arthritis. The Mobility Total Ankle System is a third-generation design consisting of a three component, cementless, unconstrained, mobile-bearing prosthesis. This study reports the early results of a multi-centre prospective study of the Mobility prosthesis. This is the first such report by independent researchers. Method. The senior authors implanted 86 consecutive Mobility prostheses. The underlying diagnosis was primary OA in 24 ankles, secondary OA in 47 ankles and inflammatory arthritis in 15 ankles. There were 41 males (Mean age 67 / Range 51–87) and 44 females (Mean age 60 / Range 29–72). The mean BMI was 28 (Range 22–36) for males, and 28 (Range 20–39) for females. Previous ankle operations were performed in 24 patients, 22 of which were for fracture fixation. Ankles were classified according to the COFAS end-stage ankle arthritis classification system. Coronal plane deformity was quantified pre-operatively. Clinical outcome was assessed using the AOFAS hindfoot score. Radiological assessment was performed from weight-bearing radiographs, documenting post-operative alignment, osseous integration, edge-loading and heterotopic bone formation. The mean follow-up time was 40 months (Range 30–60). Survival analysis was calculated according to the Kaplan-Meier method. Failure was defined as exchange of any component of the TAR, arthrodesis or amputation. Results. Type 1 ankle arthritis was demonstrated in 54 ankles (63%). No patient had pre-operative coronal plane angulation > 20. In 30 ankles (35%), the pre-operative coronal alignment was neutral, and in 32 ankles (37%), the deformity was < 10. The mean AOFAS hindfoot score improved from 37.4 (Range 12–59) pre-operatively to 77.9 (Range 51–100) post-operatively. 78 (90%) of prosthetic components were implanted within 5 of the optimal position. Bone-implant interface abnormalities were identified in 16 ankles (18%). In total, 5 TARs required revision, 4 for aseptic loosening and one for component malpositioning. There was one conversion to arthrodesis, and one BKA for CRPS. 30 simultaneous procedures were performed in 28 patients. The most common was gastrocnemius recession. There were 8 re-operations, most commonly for impingement due to peri-articular ossifications. Delayed wound healing occurred in 3 patients, and there was one case of deep infection. There were 5 patients that sustained fractures of the medial malleolus: 2 were intra-operative, and underwent internal fixation. There are 6 patients being investigated for ongoing pain. The 2-year survival was 96.4% (95% CI 89.4–99.1) and 3-year survival was 91.7% (95% CI 83.3–96.3). Conclusion. Although early results of the Mobility TAR are encouraging for independent researchers, they do not match those reported by designer surgeons. Most patients achieve good pain relief and improved function post-operatively

An increasingly used treatment for end-stage ankle osteoarthritis is total ankle replacement (TAR). However, implant loosening and subsidence are commonly reported complications, leading to relatively high TAR failure rates. Malalignment of the TAR has often been postulated as the main reason for the high incidence of these complications. It remains unclear to what extent malalignment of the TAR affects the stresses at the bone-implant interface. Therefore, this study aims to elucidate the effect of TAR malalignment on the contact stresses on the bone-implant interface, thereby gaining more understanding of the potential role of malalignment in TAR failure. FE models of the neutrally aligned as well as malaligned CCI Evolution TAR implant (Van Straten Medical) were developed. Separate models were developed for the tibial and talar segment, with the TAR components in neutral alignment and 5° and 10° varus, valgus, anterior and posterior malalignment, resulting in a total of 9 differently aligned TAR models. Loading conditions of the terminal stance phase of the gait cycle, when the force on the ankle joint is highest (5.2x body weight), were applied. Peak and mean contact pressure and shear stress at the bone-implant interface were analyzed. Also, stress distributions on the bone-implant interface were visualized. In the neutrally aligned tibial and talar TAR models, peak contact pressures of respectively 98.4 MPa and 68.2 MPa, and shear stresses of respectively 49.3 MPa and 39.0 MPa were found. TAR malalignment increases peak contact pressure and shear stress on the bone-implant interface. A maximum peak contact pressure of 177 MPa was found for the 10° valgus malaligned tibial component and the highest shear stress found was 98.5 MPa for the 10° posterior malaligned talar model. Upon TAR malalignment contact stresses increase substantially, suggesting that proper orientation of the TAR is needed to minimize peak stresses on the bone-implant interface. This is in line with previous studies, which state that malalignment considerably increases bone strains, micromotion, and internal TAR contact pressures, which might increase the risk of TAR failure. Further research is needed to investigate the relationship between increased contact stresses at the bone-implant interface and TAR failure

Ankle fusion (AF), a durable intervention for ankle arthritis, has been the management of choice but restricts mobility. Recently, total ankle replacement (TAR) has been offered to patients looking to maintain mobility. The aim was to compare the biomechanics of AF and TAR while walking on inverted and everted slopes which create a greater demand for complex foot mobility than level walking. A ten-camera motion detection setup captured trials as patients walked in both directions over a 5⁰ lateral slope with embedded force plates. Moments (Nm/Kg) across the knee and ankle were exported from Visual 3D in the sagittal and frontal plane, and data were reported as means with 95% confidence intervals. 15 patients were recruited (6 TAR, 9 AF). The median age, follow-up and BMI was 67 years, 4 years and 35.8 kg/m² in AF, and 73 years, 7 years and 28.1 kg/m² in TAR, respectively. During inverted slope walking (4 TAR, 7 AF), abduction moments across (i) the knee: TAR 0.38 (0.37–0.39) vs AF 0.37 (0.27–0.52) and (ii) the ankle: TAR 0.20 (0.13–0.27) vs AF 0.25 (0.18–0.32), and extension moments across (i) the knee: TAR 0.68 (0.38–0.97) vs AF 0.85 (0.69–1.01) and (ii) the ankle: TAR 1.46 (1.30–1.62) vs AF 1.30 (1.08–1.52). During everted walking (5 TAR, 7 AF), abduction moments across (i) the knee: TAR 0.41 (0.30–0.52) vs AF 0.46 (0.27–0.66) and (ii) the ankle: TAR 0.24 (0.11–0.38) vs AF 0.26 (0.18–0.33), and extension moments across (i) the knee: TAR 0.76 (0.54–0.99) vs AF 0.93 (0.72–1.14) and (ii) the ankle: TAR 1.39 (1.19–1.59) vs AF 1.26 (1.04–1.48). There were no differences in abduction moments during inverted or everted slope walking. However, patients with AF had increased extension moments across the knee, particularly on inverted slopes, suggesting that AF creates a greater demand for knee compensation than TAR

One assumed function of Total Ankle Replacement (TAR) is that by maintaining ankle joint motion we can protect the other hind foot joints from further degredation. 1. However, there is no work to our knowledge that compares hindfoot outcomes between TAR and arthrodesis. Sokolowski et al. found that 68% of TAR patients had no radiological progression of subtalar arthritis after TAR, and 4% went on to fusion. 2. However, no evaluation of the other hindfoot joints was made and no comparison made to other treatment. We performed a retrospective review of all patients at our centre who had had a TAR or ankle arthrodesis since 2002. Case notes and imaging were reviewed and all instances of hindfoot treatment (injections or surgical procedures) noted. Patients were excluded who had no documentation, were followed up at other hospitals, had prior hindfoot fusion, or were having staged surgeries at the time of index treatment. Chi squared analysis was used to compare the cohorts. 214 arthrodesis cases and 302 TAR were eligible. The average age was 57. Average time to follow up was 13 years (4–21). At the time of abstract submission 107 sets of notes had been reviewed fully. Full analysis will be performed by conference. 14% of TAR patients went on to have further procedures to the hindfoot joints while 35% of arthrodesis patients had further procedures (p=0.014). There was also a significant difference in the number of patients progressing to fusion of a further hindfoot joint between groups (TAR- 4%, arthrodesis- 20%, p=0.01). These data suggest that TAR are protective of symptomatic change of hindfoot joints. Patients with TAR had fewer hindfoot fusions than those with arthrodesis and also fewer procedures of any form, including injections

Introduction. Total ankle replacement (TAR) is performed for post-traumatic arthritis, inflammatory arthropathy, osteoarthritis and other indications. The Scottish Arthroplasty Project (SAP) began collection of data on TAR in 1997. In this study, using data from the SAP, we look at trends in the use and outcomes of TAR in Scotland. Methods. We identified 499 patients from the SAP who underwent TAR between 1997 and 2015 with imaging available on the National Picture Archiving and Communication System (PACS). We identified, and looked at trends in, implant type over the following time periods: 1998–2005; 2006–2010 and 2011–2015. Age, gender, indication and outcomes for each time period were examined and also trends with implant type over time. Results. There were 499 primary TAR procedures with an overall incidence of 0.5/10. 5. population per year. Eight different implants were identified with significant changes in the numbers of each type used over time. The peak incidence of TAR was in the 6th decade. The mean age of patients undergoing TAR from 59 years in 1997–2005, to 65 years in 2011–15 (p< 0.0001). The percentage of patients with inflammatory arthropathy was 52% in 1997–2005, compared with 10% in 2011–2015. Subsequent arthrodesis and infection rates appeared to be higher during the first time period. The female to male ratio also changed over time. The incidence of TAR increased overall during the study period (r= 0.9, p=< 0.0001). This may be due to a broadening range of indications and patient selection criteria, in turn due to increased surgeon experience and the evolution of implant design. Conclusion. This study examines a large number of TARs from an established arthroplasty registry. The rate of TAR has increased significantly in Scotland from 1997 to 2015. Indication and patient age has changed over time and this could potentially impact outcomes after ankle replacement

Aims. Retrospective review of a consecutive series of 1,168 total ankle replacements (TAR) performed at Wrightington, to analyse modes of failure and clinical outcomes following TAR failure. Methods. All patients undergoing TAR between November 1993 – June 2019 were collated (4–25 year follow-up; mean 13.7 years). 6 implants were used (300 STAR, 100 Buechal Pappas, 509 Mobility, 118 Zenith, 41 Salto and 100 Infinity). 5 surgeons, all trained in TAR, performed the surgery. Modes of failure were collated and clinical and radiological outcomes recorded for the revisional surgery following failure of the TAR. Results. 156 (13.4%) TARs failed (47STAR 15.6%, 16BP 16%, 77Mobility 15.1%, 6Salto 14.6%, 10Zenith 8.5% and 0Infinity 0%). Mean time to failure 5.8 years (0.1- 21.4 years). The 4 most common modes of failure were 44.9% aseptic loosening, 11.5% gutter pain, 10.9% infection and 10.3% recurrent edge loading. 50 underwent conversion to tibiotalocalcaneal (TTC) fusion with nail with 9 (18%) failing to fuse. 31 underwent revision TAR with 2 (6.5%) subsequently failed. 22 underwent ankle fusion with 10 (45%) failing to fuse. 21 underwent polyethylene exchange of which 8 (38%) had further poly failure. 20 (12.8%) were managed conservatively, 2 (1.3%) required below knee amputation and 6 were listed but lost to follow-up. 81 of the 1168 (7%) consecutive cohort were lost to follow-up. Conclusions. 13.4% of the TAR cohort have failed at average follow-up 13.7 years. There was no difference in failure modes across the implant designs. Whilst the fixed bearing has the shortest follow-up, it may be performing better as there have been no failures so far. Prior to October 2016, most revisions were to fusion (TTC 18% failure rate, ankle 45% failure rate), whereas post 2016, 57% patients elected for revision TAR (6.5% failure)

Introduction. Primary ankle arthroplasty (TAR) is increasingly used to treat end-stage ankle arthritis. Reported revision rates of TAR vary from 8.5% to 11.1% at 9 years. Revision surgery remains technically challenging with options ranging from simple joint debridement to tibio-talar-calcaneal fusion. The efficacy of these procedures remains unclear and there is no consensus on optimal revision options. Methods. A retrospective cohort study was performed of all patients undergoing surgery for a failed primary TAR at the Nuffield Orthopaedic Centre (2004–2021). TAR failure was determined by clinical assessment, serial radiographs and CT scans. Primary outcome measures included type and time of index surgery post TAR. Secondary outcomes included frequency of re-operations, post-operative complications, patient reported outcomes and union rate (for revision arthrodesis procedures). Results. 70 failed TARs in 69 patients (35M:34F, mean 65.7 years, s.d.=11.6) underwent re-operation a mean of 6.24 years (range 1–30) post primary. In total, 107 operations were performed including revision fusion (n=50), revision arthroplasty (n=14), bearing exchange (n=9) and joint clearance (n=9). The overall revision fusion union rate was 73.5% over a mean of 12.5 months (s.d.=7.6). 16/23 (69.6%) Tibio-Talo-Calcaneal and 9/12 (75%) ankle fusions (previous subtalar/triple fusion) using a hindfoot nail united over a mean 11.4 months (s.d.=6.0) and 15 months (s.d.=9.48) respectively. Only 64% of ankle fusions using screws alone united (mean=10.6 months, s.d.=8.14). The average post-operative MOXFQ score was 28.3 (s.d.=19.3). 73% said the operation improved their function and would recommend it to a friend/family member. Conclusion. Despite low post-operative MOXFQ scores, over 70% of patients were satisfied with re-operation for a failed TAR. Over 26% of all TAR revision fusions fail to unite with the highest non-union rates observed post ankle arthrodesis with screws alone (36.4%)

Preoperative talar valgus deformity increases the technical difficulty of total ankle replacement (TAR) and is associated with an increased failure rate. Deformity of ≥15° has been reported to be a contraindication to arthroplasty. The goal of the present study was to determine whether the operative procedures and clinical outcomes of TAR for treatment of end-stage ankle arthritis were comparable for patients with preoperative talar valgus deformity of ≥15° as compared to those with <15°. We will describe the evolving surgical technique being utilized to tackle these challenging cases. Fifty ankles with preoperative coronal-plane tibiotalar valgus deformity of ≥15° “valgus” group) and 50 ankles with valgus deformity of <15° (“control” group) underwent TAR. The cohorts were similar with respect to demographics and components used. All TARs were performed by a single surgeon. The mean duration of clinical follow-up was 5.5 years (minimum two years). Preoperative and postoperative radiographic measurements of coronal-plane deformity, Ankle Osteoarthritis Scale (AOS) scores and Short Form (SF)-36 scores were prospectively recorded. All ancillary (intraoperative) and secondary procedures, complications and measurements were collected. The AOS pain and disability subscale scores decreased significantly in both groups. The improvement in AOS and SF-36 scores did not differ significantly between the groups at the time of the final follow-up. The valgus group underwent more ancillary procedures during the index surgery (80% vs 26%). Tibio-talar deformity improved significantly toward a normal weight-bearing axis in the valgus group. Secondary postoperative procedures were more common in the valgus group (36%) than the controls (20%). Overall, re-operation was not associated with poorer patient outcome scores. Metal component revision surgery occurred in seven patients (three valgus and four controls). These revisions included two deep infections (2%), one in each group, which were converted to hindfoot fusions. Therefore, 94% of the valgus group retained their original components at final follow-up. Thus far, this is the largest reported study that specifically evaluates TAR with significant preoperative valgus alignment, in addition to having the longest follow-up. Satisfactory midterm results were achieved in patients with valgus mal-alignment of ≥15°. The valgus cohort required more procedures during and after their TAR, as well as receiving more novel techniques to balance their TAR. Whilst longer term studies are needed, valgus coronal-plane alignment of ≥15° should not be considered an absolute contraindication to TAR if the associated deformities are addressed

Varus ankle osteoarthritis (OA) is typically associated with peritalar instability, which may result in altered subtalar joint position. This study aimed to determine the extent to which total ankle replacement (TAR) in varus ankle OA can restore the subtalar position alignment using 3-dimensional semi-automated measurements on WBCT. Fourteen patients (15 ankles, mean age 61) who underwent TAR for varus ankle OA were retrospectively analyzed using semi- automated measurements of the hindfoot based on pre-and postoperative weightbearing WBCT (WBCT) imaging. Eight 3-dimensional angular measurements were obtained to quantify the ankle and subtalar joint alignment. Twenty healthy individuals were served as a control groups and were used for reliability assessments. All ankle and hindfoot angles improved between preoperative and a minimum of 1 year (mean 2.1 years) postoperative and were statistically significant in 6 out of 8 angles (P<0.05). Values The post-op angles were in a similar range to as those of healthy controls were achieved in all measurements and did not demonstrated statistical difference (P>0.05). Our findings indicate that talus repositioning after TAR within the ankle mortise improves restores the subtalar position joint alignment within normal values. These data inform foot and ankle surgeons on the amount of correction at the level of the subtalar joint that can be expected after TAR. This may contribute to improved biomechanics of the hindfoot complex. However, future studies are required to implement these findings in surgical algorithms for TAR in prescence of hindfoot deformity

Background. Total ankle replacements (TARs) are becoming increasingly more common in the treatment of end stage ankle arthritis. As a consequence, more patients are presenting with the complex situation of the failing TAR. The aim of this study was to present our case series of isolated ankle fusions post failed TAR using a spinal cage construct and anterior plating technique. Methods. A retrospective review of prospectively collected data was performed for 6 patients that had isolated ankle fusions performed for failed TAR. These were performed by a single surgeon (IW) between March 2012 and October 2014. The procedure was performed using a Spinal Cage construct and grafting in the joint defect and anterior plating. Our primary outcome measure was clinical and radiographic union at 1 year. Union was defined as clinical union and no evidence of radiographic hardware loosening or persistent joint lucent line at 1 year. Results. The mean follow-up was 37.3 months (SD 13.2). Union was achieved in 5 of the 6 patients (83%). One patient had a non-union that required revision fusion incorporating the talonavicular joint that successfully went on to unite across both joints. Another patient had radiographic features of non-union but was clinically united and asymptomatic and one required revision surgery for a bulky symptomatic lateral malleolus with fused ankle joint. Conclusion. The failing TAR presents a complex clinical situation. After removal of the implant there is often a large defect which if compressed leads to a leg length discrepancy and if filled with augment can increase the risk of non-union. Multiple methods have been described for revision, with many advocating fusion of both the ankle joint and subtalar joint. We present our case series using a spinal cage and anterior plating that allows preservation of the subtalar joint and a high rate of union

Introduction. We report the functional outcome and survivorship of the Hintegra Total Ankle Replacement (TAR), in consecutive cases by multiple surgeons in a single UK institution. Between 2010–2014 the Hintegra TAR held 7.1% UK market share and surgeons should be aware of failure mechanisms. Methods. We conducted a retrospective review of prospectively collected data for 70 consecutive Hintegra TAR cases in a single institution between 2010–2014. Data collected included patient demographics, complications, reoperations, patient reported outcome measures (PROMS: AOS, MOX-FQ, pain VAS) and patient satisfaction. Results. The 70 patients (54 male/ 16 female) had an average age of 69 (range 48–84 years). Mean follow up was 76 months (range 60–04), 10 patients died during the follow up. Implant survivorship was 81.4% at most recent follow up. The commonest radiographic finding was periprosthetic cysts (n=28, 40%), size range (7–40mm), location of cysts: isolated talus (n=14), isolated tibia (n=6), mixed (n=8). 10 failed TARs were revised to Inbone TAR at a mean of 48 months (range 9–69). 3 Failed TARs were revised to arthrodesis (2 tibiotalar fusions, 1 hindfoot nail). 11 patients required reoperation with implant retention: 8 periprosthetic cyst debridement and grafting at a mean of 61 months (range 27–91), 1 lateral gutter debridement and 1 periprosthetic fracture ORIF. PROMS data was available for all patients. Overall patients showed marked improvement in functional outcome scores between pre-operative and final follow up questionnaires. Mean pre-op AOS: 62, MOX-FQ: 68 and pain VAS: 67.5 with mean final follow up scores of: AOS: 35, MOX-FQ: 36 and pain VAS: 30. Conclusion. Our experience demonstrates improved PROMS following ankle arthroplasty for patients with a mean follow up of 6.4 years. Implant survivorship is similar to other TAR studies. We have identified a high incidence of periprosthetic cysts and would recommend ongoing surveillance of these patients

Total ankle replacement (TAR) is performed for inflammatory arthropathy, osteoarthritis and other indications. The Scottish Arthroplasty Project (SAP) began collection of data on TAR in 1998. In this study, we look at trends in the use and outcomes of TAR in Scotland. We identified patients from the SAP who underwent TAR between 1998 and 2015 with imaging available on the National Picture Archiving and Communication System (PACS). We identified, and examined trends in implant type over the following time periods: 1998–2005; 2006–2010 and 2011–2015. Age, gender, indication, outcomes and trends in implants used for each time period were examined. There were 499 primary TAR procedures with an overall incidence of 0.5/105 population per year. Eight implants were identified with significant changes in the numbers of each type used over time. The peak incidence of TAR was in the 6th decade and mean age of patients increased from 59 years in 1998–2005, to 65 years in 2011–15 (p<0.0001). The percentage of patients with inflammatory arthropathy was 49% in 1998–2005, compared with 10% in 2011–2015. Arthrodesis and infection rates appeared to be higher during the first time period. The male to female ratio changed over time. The incidence of TAR increased overall during the study period (r= 0.9, p=<0.0001). This study examines a large number of TARs from an established arthroplasty registry. The rate of TAR has increased significantly in Scotland from 1998 to 2015. Indications and patient age have changed over time and could impact outcomes after ankle replacement

Introduction. Comparative studies examining Fixed-Bearing (FB) and Mobile-Bearing (MB) Total Ankle Replacement (TAR) designs have demonstrated similar results and successful long-term outcomes for both. To date there has been no study directly comparing FB and MB designs of the same prosthesis. We present the first prospective randomised trial comparing patient satisfaction, functional outcomes and radiographic results of the Salto Talaris Fixed-Bearing and the Salto Mobile-Bearing Total Ankle Replacement in the treatment of end-stage ankle arthritis. Methods. A total of 108 adult patients with end-stage ankle arthritis were enrolled in the study between November 2014 and October 2021 with similar demographic comparison. Prospective patient-reported outcomes and standardised weightbearing ankle radiographs were performed preoperatively, at 6 weeks, 6 months and 12 months post-operatively, followed by yearly intervals. All surgeries were performed by a single non-design orthopaedic foot and ankle specialist with experience in over 200 Salto and Salto Talaris TAR prior to the study. Radiographs were examined independently by two clinicians. Complete patient data and radiographs were available for 103 patients with an average follow up of 2 years. Results. Both groups demonstrated statistically significant improvement from preoperative evaluation to most recent follow up with no statistically significant difference between the two groups in all outcome measures. Radiographic incidence of subchondral cyst formation was 8.9% and 38.2% for FB and MB, respectively. Talar subsidence occurred in 2.2% and 5.5% of FB and MB, respectively. Discussion. Our study demonstrates a higher than previously reported rate of cyst formation in the MB TAR and comparatively higher talar subsidence in the MB TAR vs FB however this did not correlate with clinical outcome measures which were favourable for both groups. Conclusion. Fixed-Bearing and Mobile-Bearing Total Ankle Replacement demonstrate comparable favourable

Background. The importance of total ankle replacement (TAR) implant orientation in the axial plane is poorly understood with major variation in surgical technique of implants on the market. Our aims were to better understand the axial rotational profile of patients undergoing TAR. Methods. In 157 standardised CT Scans of end-stage ankle arthritis patients planning to undergo primary TAR surgery, we measured the relationship between the knee posterior condylar axis, the tibial tuberosity, the transmalleolar axis(TMA) and the tibiotalar angle. The foot position was measured in relation to the TMA with the foot plantigrade. The variation between medial gutter line and the line bisecting both gutters was assessed. Results. The mean external tibial torsion was 34.5±10.3°(11.8–62°). When plantigrade the mean foot position relative to the TMA was 21±10.6°(0.7–38.4°) internally rotated. As external tibial torsion increased, the foot position became more internally rotated relative to the TMA(pearson correlation 0.6;p< 0.0001). As the tibiotalar angle became more valgus, the foot became more externally rotated relative to the TMA(pearson correlation −0.4;p< 0.01). The mean difference between the medial gutter line and a line bisecting both gutters was 4.9±2.8°(1.7°-9.4°). More than 51% of patients had a difference greater than 5°. The mean angle between the medial gutter line and a line perpendicular to the TMA was 7.5°±2.6°(2.8°-13.7°). Conclusion. There is a large variation in rotational profile of patients undergoing TAR, particularly between the medial gutter line and the transmalleolar axis. Surgeon designers and implant manufacturers need to develop consistent methods to guide surgeons towards judging appropriate axial rotation of their implanton an individual basis. We recommend careful clinical assessment and CT scanspre-operatively to enable the correct rotation to be determined

Abstract. Introduction. Ankle arthritis is estimated to affect approximately 72 million people worldwide. Treatment options include fusion and total ankle replacement (TAR). Clinical performance of TAR is not as successful as other joint replacement and failure is poorly understood. Finite element analysis offers a method to assess the strain in bone implanted with a TAR. Higher strain has been associated with microfracture and alters the bone-implant interface. The aim of this study was to explore the influence of implant fixation on strain within the tibia when implanted with a TAR through subject-specific models. Methods. Five cadaveric ankles were scanned using a Scanco Xtreme CT. The Tibia and Talus were segmented from each scan and virtually implanted with a Zenith TAR (Corin, UK) according to published surgical technique. Patient specific models were created and run at five different positions of the gait cycle corresponding to peak load and flexion values identified from literature. Bone material properties were derived from CT greyscale values and all parts were meshed with linear tetrahedral elements. The implant-bone interface was adjusted to fully-fixed or frictionless contact, representing different levels of fixation post-surgery. Strain distributions around the tibial bone fixation were measured. Results. Initial results showed clear differences in strain distributions both between different ankle specimens and fixation levels, with highest strain occurring within the bone at the tip of the tibial stem. Frictionless contact gave higher strain outputs than fully-fixed for all specimens with a range 0.12–0.3% and 0.07%–0.13% respectively. Conclusions. In all specimens, strain was higher in the frictionless contact, which may be considered representative of no bony ingrowth, highlighting fixation may be a critical factor in TAR failure. Differences observed between specimens highlights that TAR may not be a suitable intervention for all patients, due to variation in bone quality and anatomy. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Recent advances in arthroplasty for the hip and the knee have motivated modern foot and ankle research to perfect the implant and technique for the optimal total ankle replacement. Unlike in the hip where different approaches can be done with similar implants, the approach of a total ankle is intimately associated to the prosthetic design. The anterior and lateral approaches have pros and cons regarding their respective soft tissue complications, osteotomy necessity, orientation of the bone cut and gutter visualization. While both have been studied independently, very few reports have compared both in the same setting. This study retrospectively looked at the difference in reoperations rate after each ankle arthroplasty within two years estimating that both had similar rate of return to the operating room. A retrospective study was conducted from a single center between 2014 and 2017 including a total of 115 total ankles performed by one of four fellowship-trained foot and ankle surgeon. Re-operations were reported in the charts as an operative report. The index approach used was determined by the surgeon's practice preference. Patients were included when they had a primary TAR in the timeframe noted and had a complete dataset up to at least the two-year data. This cohort comprised 67 anterior and 48 lateral with balanced demographic for age (95%CI 63–67 yo) and gender (47% F). The lateral group had more complex cases with higher COFAS type arthritis. Comparing the two groups, a total of 40 reoperations (7 anterior, 33 lateral) occurred in 27 patients (5A, 22L). One patient had up to four related reoperations. The only revision was in the anterior group. The only soft tissue reconstruction was an STSG in the lateral group. Nine reoperations were irrigation debridement related to an infective process (3 A, 6L). The majority (19/33) of reoperations in the lateral group were gutter debridement (8) or lateral hardware removal (11). Operative time was not statistically different. The odds ratio of having a reoperation with a laterally based TAR was 6.19 compared to the anterior group. This retrospective study outlines the intermediate results at two years of lateral and anterior total ankle replacements. This is a first study of this kind in the literature. This study did show that there were more reoperations after a laterally-based TAR than an anterior TAR, recognizing the significant case complexity imbalance between groups. This speaks to the relative increase resource utilization of laterally based TAR patients. Both implant designs carry different reoperation rates favoring the anterior group however larger prospective datasets will be needed with patient-reported outcome

Aim. Surgical options for management of a failed ankle arthroplasty are currently limited; typically conversion to fusion is recommended with only a few patients being considered for revision replacement surgery. This paper presents our experience of revision ankle replacements in a cohort of patients with failed primary replacements. Method. A total of 18 revision TAR in 17 patients were performed in patients with aseptic loosening. The technique was performed by a single surgeon (CSK) over a 4 year period between July 2014 and August 2018 using the Inbone total ankle replacement system. Patient demographics and clinical outcomes were collected retrospectively using - MOXFQ, EQ5D, VAS pain score and patient satisfaction questionnaires. Results. 12 right and 6 left ankle replacements were revised in 17 patients (11 male/ 6 female). The mean age at revision was 69.1 years (range 56–81 years) with a mean BMI of 31. The mean surgical time was 171 minutes with 22% of cases requiring bone grafting. 6 patients had early wound complications, all superficial and settled with dressings. There were no deep infections, 2 patients had further surgery for exploration for possible nerve injuries. At a mean follow up of 20.6 months, 4 patients had mild/moderate ongoing pain with the majority of patients being satisfied with the outcome of their surgery. Conclusion. This study represents one of the largest group of patients reported to have undergone revision total ankle arthroplasty. Our experience shows that this results in acceptable level of complications and provides satisfactory function in most patients. We feel revision TAR is a viable option in patients with failed primary arthroplasty who wish to continue to maintain mobility at the ankle joint

Introduction. Day Case Surgery (defined as same day discharge) is a priority within the National Health Service and has been shown to provide beneficial outcomes for patients and hospitals. We report our experience developing a Day Case Programme for Total Ankle Replacement (TAR). Methods. Prior to the introduction of a Day Case Programme, average length of stay following TAR in our unit was 3.5 days. Stakeholders were consulted about ways in which same day discharge could be facilitated. Patients' post-operative pain charts were reviewed prior to the introduction of this programme. Inclusion criteria included non-complex surgery (anticipated tourniquet < 2hrs), friend or relative support and pre-operative walking-aid assessment. An enhanced recovery protocol included long-acting popliteal block and dexamethasone. Patients were discharged with opiate analgesia and written pain instructions. Patients were asked to complete a pain and satisfaction questionnaire. Patient Reported Outcome Measures (PROMs) were recorded. Results. From September 2017 to April 2019 21 of 70 patients underwent TAR as a Day Case. Mean age was 67 years (43-85 years). Complications included two delayed wound healings and one representation on day three with urinary retention. No patients reported post-operative nausea or vomiting, 60% did not use Oramorph at home. Average Visual Analogue Score for pain was 23/100 on day one and 21/100 day three post-operatively. There was no significant difference in pre-operative or overall change in MOXFQ, VAS or EQ5D PROMS. Conclusions. Early results suggest that Day Case Total Ankle Replacements are safe. Appropriate patient selection is necessary. Day Case Surgery relies on support and communication between multiple teams to organise and run effectively