scholarly journals TL 18183 - Total ankle arthroplasty

2019 ◽  
Vol 13 (Supl 1) ◽  
pp. 105S
Author(s):  
André Vitor Kerber Cavalcanti Lemos ◽  
Caio Augusto De Souza Nery ◽  
Daniel Soares Baumfeld
Keyword(s):  
Sagittal Plane ◽  
Clinical Status ◽  
Total Ankle Arthroplasty ◽  
Significance Level ◽  
Implementation Phase ◽  
Ankle Arthroplasty ◽  
Bone Properties ◽  
Parametric Data ◽  
Wright Medical Technology

Introduction: Total ankle arthroplasty (TAA) is an alternative for the treatment of end-stage ankle arthrosis that is still in the implementation phase in Brazil. The objective of this study is to present the clinical and radiographic outcomes of the INBONE II prosthesis assessed by the Ankle and Foot Groups of the Department of Orthopedics and Traumatology of the Paulista School of Medicine at Federal University of São Paulo and Federal University of Minas Gerais. Methods: From November 2016 to December 2018, 13 TAAs were performed in 13 patients (4 females: 31%; 9 males: 69%) with ages ranging from 41 to 84 years (mean: 58 years) using INBONE II implants (Wright Medical Technology, USA). Parametric data on arthrosis etiology, clinical status (visual analog scale (VAS) and American Orthopedic Foot and Ankle Society (AOFAS) scores), implant positioning and bone cut adequacy (lateral tibial slope (LTS), alpha, beta and theta angles and distances "a" and "b") were collected, in addition to short-term qualitative bone properties (periprosthetic bone cysts and tibial and talar component sinking and wear). We also collected immediate and early postoperative data on associated surgeries, complications and reinterventions. All data were subjected to statistical analysis at the 5% significance level. Results: The VAS (pre 8; post 2) and AOFAS (pre 37; post 80) scores significantly improved at the end of a mean follow-up period of 10 months (min 1 month: max 2 years, 2 months). The immediate and early postoperative tibial and talar component alignment was within 2 degrees of deviation from the ideal in the sagittal plane in 84% patients and in the coronal plane in 92% patients, with an LTS below 5 mm in 100% of patients and good correction of radiographic parameters, even in cases of arthroplasty revision. Conclusion: Total ankle replacement is a good alternative for the treatment of advanced arthrosis of the ankle, and the INBONE II prosthesis is seems to be a good option for cases of arthroplasty failure due to loosening or malalignment. Longer follow-up is needed to evaluate intermediate and long-term outcomes.

scholarly journals The Infinity Total Ankle System

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0038
Author(s):  
Murray Penner ◽  
W. Hodges Davis ◽  
Thomas Bemenderfer ◽  
Feras Waly ◽  
Robert Anderson
Keyword(s):  
Mobile Bearing ◽  
Clinical Results ◽  
Outcome Data ◽  
Total Ankle Arthroplasty ◽  
Ankle Arthroplasty ◽  
Radiographic Outcomes ◽  
Wright Medical Technology ◽  
The Usa ◽  
Component Revision

Category: Ankle Arthritis Introduction/Purpose: Background: Increasing interest in 2-component total ankle arthroplasty (TAA) designs and the increased use of TAA overall has led to the development of a new generation of 2-component TAA implants. The first of these to become available was the Infinity Total Ankle System (Wright Medical Technology, Memphis, TN), introduced in 2014. Despite it currently being the most commonly used TAA implant in the UK and among the most commonly used in the USA, published clinical results are lacking. Purpose: This study presents the first report of the clinical and radiographic outcomes of the Infinity Total Ankle System with minimum 2 year follow-up Methods: The first 67 consecutive patients who underwent primary Infinity total ankle arthroplasty (TAA) at 2 North American sites between 2013 and 2015 were reviewed in a prospective observational study. Demographic, radiographic, and functional outcome data was collected preoperatively, at 6-12 months postoperatively, and annually thereafter. Results: The overall implant survival rate was 97% (65 of 67 implants) at mean follow up of 3 years (range 27-47 months). Two cases underwent talar component revision for aseptic loosening. Six of the 67 cases (9%) required a non-revision reoperation. Mean FFI and AOS scores at latest follow up improved from preoperative by 21.6 (p<0.0001) and 34.0 (p<0.0001), respectively. No radiographic loosening of any talar or tibial components was identified in the 65 non-revised cases. Conclusion: Early clinical and radiographic outcomes with the Infinity TAA are promising and compare favorably to those reported for both fixed- and mobile-bearing third generation TAA designs, even when used in cases with deformity and increased case complexity.

scholarly journals Salvage Arthrodesis with Femoral Head Allograft for Failed Total Ankle Arthroplasty

2020 ◽  
Vol 5 (4) ◽  
pp. 2473011420S0032
Author(s):  
Hong S. Lee ◽  
Kiwon Young ◽  
Tae-Hoon Park ◽  
Hong Seop Lee
Keyword(s):  
Femoral Head ◽  
Subjective Assessment ◽  
Total Ankle Arthroplasty ◽  
Bone Block ◽  
Ankle Arthroplasty ◽  
Pain Scores ◽  
Walking Aids ◽  
The Mean ◽  
Final Followup

Category: Ankle Introduction/Purpose: Failed total ankle arthroplasty (TAA) often results in significant bone loss and requires salvage arthrodesis. The aim of this study was to investigate the outcomes of Salvage arthrodesis with allo-bone block for failed TAA. Methods: This study included 8 patients who underwent salvage arthrodesis with femoral head allograft for failed TAA from August 2012 to March 2018 because of loosing of TAA implant. The mean age of the patients was 71 years (range, 54-81 years), and the mean follow-up period was 32 months (range, 12 to 84 months). Allograft problem and alignment of joint were evaluated radiographically. American Orthopaedic Foot & Ankle Society (AOFAS) scores, Foot and Ankle Outcome Score (FAOS), and visual analogue scale (VAS) pain scores were recorded preoperatively and at the time of final followup. Functional questionnaires were used to assess the duration for which the patient could walk continuously, use of walking aids, consumption of pain medication, and the patient’s subjective assessment of the percentage of overall improvement compared with before the salvage arthrodesis. Results: The allograft was retained without collapse for a mean of 24 months (range, 12 to 36 months) in four patients. Collapse of the allograft was observed in four patients at a mean of 11 months (range, 9 to 16 months), 1 of 4 patients were conserved to retrograde intramedullary nail at postoperative 12 months because of with implant failure and nonunion. The mean AOFAS and VAS pain scores improved from 12 (range, 8 to 40) preoperatively to 63 (range, 38 to 75) postoperatively (p = 0.001) and from 7 (range, 6 to 10 to 3 (range, 2 to 8) (p = 0.001), respectively. At the final follow-up evaluation, 6 of 8 patients were able to walk continuously at least 30 minutes with walking aid. Conclusion: The successful rate of salvage arthrodesis with femoral head allograft was 75% (Six of total 8 patients). The incidence rate of allograft collapse was 50% (Four of total 8 patients).

scholarly journals Effect of Travel Time and Distance on Outcomes in Total Ankle Arthroplasty

2020 ◽  
Vol 5 (4) ◽  
pp. 2473011420S0015
Author(s):  
Kristin C. Caolo ◽  
Scott J. Ellis ◽  
Jonathan T. Deland ◽  
Constantine A. Demetracopoulos
Keyword(s):  
Travel Time ◽  
Complication Rate ◽  
High Volume ◽  
Total Ankle Arthroplasty ◽  
Complication Rates ◽  
Linear Regression Models ◽  
Ankle Arthroplasty ◽  
Significant Difference ◽  
Drive Time

Category: Ankle; Ankle Arthritis Introduction/Purpose: Surgeons who perform a higher volume of total ankle arthroplasty (TAA) are known to have decreased complication rates; evidence shows that low volume centers performing TAA have decreased survivorship when compared with high volume centers. Understanding differences in outcomes for patients traveling different distances for their TAA is important for future patients deciding where to travel for their surgery. No study has previously examined differences in outcomes of patients traveling different distances to a high volume center for their TAA. This study compares preoperative and postoperative PROMIS scores for patients undergoing total ankle arthroplasty who traveled less than and more than 50 miles for their TAA. We hypothesized that there would be no difference in outcome scores based on distance traveled or estimated drive time. Methods: This study is a single center retrospective review of 162 patients undergoing primary total ankle arthroplasty between January 2016 and December 2018. We collected the primary address as listed in the patient’s medical record and used the directions feature on Google Maps to estimate driving mileage and estimated driving time from the patient’s address to the hospital. To analyze the distance patients traveled, patients were divided into two groups: <50 miles traveled (n=91) and >50 miles traveled (n=71). To analyze the estimated drive time, patients were divided into two groups: <90 minutes (n=77), >90 minutes (n=85). We collected preoperative and most recent postoperative PROMIS scores for all patients. Differences in most recent post-operative PROMIS scores between distance groups and travel time groups were assessed using multivariable linear regression models, adjusting for the pre-operative score and follow-up time. Results: We found no significant difference in post-operative PROMIS scores between the two groups when analyzed for distance traveled or for estimated travel time after adjustment for pre-operative PROMIS score and follow-up time (Table 1). The average follow-up for all 162 patients was 1.49 years. Power analysis showed that with a sample size of 110 (55 in each group), we had 81% power to detect an effect size of 4. Patients saw an increase in their Physical Function scores and a decrease in their Pain Interference and Pain Intensity scores with postoperative scores better than population means (Table 1). Overall complication rate for the <50 miles group was 17.6%, 7.7% required surgery. The >50 miles group had an overall complication rate of 24.0%, 9.9% required surgery. Conclusion: Patients traveling further distances to a high volume orthopedic specialty hospital for their total ankle arthroplasty do not have different clinical outcomes than patients traveling shorter distances. This is particularly important for patients deciding where to have their total ankle arthroplasty surgery. Patients who travel further have the opportunity to be treated at a local academic center; however our results show that outcomes do not change when traveling further for total ankle arthroplasty. [Table: see text]

scholarly journals Axial Rotational Alignment of Mobile-Bearing Total Ankle Arthroplasty

2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0021
Author(s):  
Beat Hintermann ◽  
Lukas Zwicky ◽  
Christine Schweizer ◽  
Alexej Barg ◽  
Roxa Ruiz
Keyword(s):  
Tibial Component ◽  
Mobile Bearing ◽  
Total Ankle Arthroplasty ◽  
Axial Position ◽  
Anterior Surface ◽  
Ankle Arthroplasty ◽  
Medial Border ◽  
Wide Range ◽  
Angle Of Rotation

Category: Ankle Arthritis Introduction/Purpose: In total ankle arthroplasty (TAA), component malpositioning is a major cause of implant failure, possibly due to the altered force patterns caused by the malpositioning which are then transmitted to the bone-implant interface or neighboring joints during physiological loading. Mobile-bearing TAA with their second interface, may allow the talus to adapt its position based upon the individual anatomy. However, no data exist on the change in component positioning after implantation. It is unclear whether it is the result of initial positioning during implantation or secondary adjustments such as possible soft tissue adaptions. We aimed to determine the relative axial rotation between the talar and tibial components at the end of surgery and after a minimum of 3 years follow-up. Methods: The relative rotation between the tibial and talar components was measured in two groups. First, intraoperatively before wound closure, in a consecutive series of 58 patients (60 ankles; age 61.8 [31 to 86] years; females 25, males, 35) who underwent TAA between February and November 2018. A K-wire inserted along the medial border of the tibial component and a rectangular marker positioned at the anterior surface of PE insert were used to determine the angle of rotation. Second, in 48 patients (48 ankles; age 60.2 [31 - 82] years; females, 24; males, 24) out of 1411 patients who underwent TAA between January 2003 and December 2015, and in whom a weight-bearing CT scan was taken for evaluation at 6.3 (range, 3.0 -16.3) years. The medial border of the tibial component and a perpendicular line to the anterior surface of the PE insert were used to determine the angle of rotation. Results: The angle of rotation, thus the relative position of the talar component compared to the tibial component, did not differ between the two groups (p = 0.2). While the talus was internally rotated by 1.7 (range, -14.0 - 14.0) degrees at the end of surgery, it was internally rotated by 1.5 (range, -13.0 – 19.5) degrees after a minimum follow-up of 3 years (Figure 1). Conclusion: Although there was no significant difference in average axial position measured intraoperatively compared to a 3- years follow-up, there was a wide range of rotational measurements. The possibility of the talar component to find its position as given by individual anatomy may be crucial in TAA to avoid non-physiological joint loads and shear forces which may otherwise result in increased PE wear. Due to the wide range of measurements, our data suggests that axial talar rotation cannot be predicted preoperatively or intraoperatively by surgical techniques that reference the transtibial axis, tibial tuberosity and transmalleolar axis as guidance for tibial component positioning.

scholarly journals Role of Total Ankle Arthroplasty in Stiff Ankles – Long Term Follow-Up

2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0001
Author(s):  
James W. Brodsky ◽  
Justin M. Kane ◽  
Andrew W. Pao ◽  
David D. Vier ◽  
Scott Coleman ◽  
...  
Keyword(s):  
Range Of Motion ◽  
Step Length ◽  
Total Ankle Arthroplasty ◽  
Ankle Arthritis ◽  
Ankle Arthroplasty ◽  
Post Surgery ◽  
Long Term Follow Up ◽  
Gait Function

Category: Ankle, Ankle Arthritis Introduction/Purpose: Operative treatment of end-stage ankle arthritis involves either ankle arthrodesis (AA) or total ankle arthroplasty (TAA). The theoretical benefit of TAA is the ability to preserve range of motion (ROM) at the tibiotalar joint. Previous studies have questioned whether it is justified to perform TAA over AA in stiff, arthritic ankles. However, a recent study showed that patients who underwent TAA with stiff ankles preoperatively experienced significant clinical improvement in range of motion and gait function compared to more flexible groups at 1-year follow-up. We retrospectively assessed these same gait and functional parameters to see if these improvements held up in long-term follow-up. Methods: A retrospective study of long-term, prospectively collected functional gait data in 33 TAA patients at a mean of 7.6 years postoperatively (range 4.8-13.3) used a multivariate regression model to determine the effect of ankle stiffness on the long- term, objective outcomes of TAA. Data was analyzed by quartiles (Q1, Q2+Q3, Q4) of preoperative sagittal ROM using one-way analysis of variance (ANOVA) to compare both preop and postop gait parameters. The two middle quartiles were combined to conform to distribution of the data. The multivariate analysis determined the independent effect of age, gender, BMI, years post- surgery, and preop ROM on every preop and postop parameter of gait. Results: Statistically significant differences were found in all three gait parameter categories, including temporal-spatial (step length and walking speed), kinematic (total sagittal ROM and maximum plantarflexion), and kinetic (peak ankle power). The stiffest ankles preoperatively (Q1) had the greatest absolute increase in total sagittal ROM postoperatively, +5.3o, compared to -1.3o (p<0.0174) in Q4 (most flexible). However, Q1 had the lowest absolute total postoperative sagittal ROM of 13.1 o, compared to 19.7 o (p<0.0108) in Q4. Q1 also had the lowest preoperative step length, walking speed, maximal plantarflexion, and peak ankle power when compared to the other subgroups. There was no difference in any of these same parameters postoperatively. BMI and years post-surgery had no effect on outcomes, while age and gender had a minimal effect. Conclusion: Preoperative range of motion was once again predictive of overall postoperative gait function in long-term follow-up at an average of 7.2 years. A greater degree of preoperative sagittal range of motion was predictive of greater postoperative sagittal range of motion in long-term follow-up. Patients with the stiffest ankles preoperatively once again had a statistically and clinically greater improvement in function as measured by multiple parameters of gait. This shows that the clinically meaningful improvement in gait function after total ankle arthroplasty holds up in long-term follow-up, even in the setting of limited preoperative sagittal range of motion.

scholarly journals Conversion of Ankle Fusions to Ankle Replacements

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0051
Author(s):  
Stephen White ◽  
Bruce Cohen ◽  
Carroll Jones ◽  
Michael Le ◽  
W. Hodges Davis
Keyword(s):  
Ankle Arthrodesis ◽  
Total Ankle Arthroplasty ◽  
Ankle Arthritis ◽  
Ankle Arthroplasty ◽  
Patient Reported ◽  
Fusion Site ◽  
Foot Function ◽  
Patient Related Outcome ◽  
Improved Function

Category: Ankle Arthritis Introduction/Purpose: Ankle arthrodesis remains a prominent treatment choice for ankle arthritis in a majority of patients. Long term studies have shown a compensatory development of ipsilateral adjacent joint arthritis after ankle arthrodesis, and some patients who receive an ankle arthrodesis develop pain in surrounding joints, or even at the fusion site. As total ankle arthroplasty (TAA) design, instrumentation, and techniques have improved, the use of total ankle arthroplasty has become more widespread. Very few studies have been published on conversion of ankle arthrodesis to ankle arthroplasty, but they have shown improved function and patient-related outcome scores. The purpose of this study was to assess the radiographic, clinical, and patient-reported outcomes of patients undergoing ankle arthroplasty after conversion from a CT-confirmed ankle arthrodesis. Methods: This was a retrospective cohort study of patients with previous CT-confirmed ankle arthrodesis who underwent conversion to total ankle arthroplasty. Minimum follow up was 1 year. Nonunions of ankle arthrodesis were excluded. AOFAS ankle-hindfoot score, foot function index (FFI), pain, revision surgeries, complications, and patient demographics were assessed. Radiographs prior to TAA, and at latest follow-up were also reviewed. Results: 10 patients were included in the study with an average age of 54.5 years. No implants had to be revised. 1/10 (10%) patients had to undergo secondary surgery for heterotopic ossification removal. The same patient had to undergo another subsequent surgery for posterior ankle decompression. 2/10 (20%) patients had a mild talar subsidence of the TAA at latest follow-up, with no patients having tibial subsidence. Talar osteolysis was noticed in 2 patients (20%) at latest follow-up, with no patients having tibial osteolysis. Only one patient (10%) was noted to have a mild valgus alignment of TAA with no varus malalignments. All radiographic changes noted were clinically asymptomatic. The average AOFAS total score was 58 (range 23,89). The mean FFI total score was 41.9 (range 0,90). Conclusion: Conversion of ankle fusion to TAA is a challenging operation but can be a viable option for patients with ongoing pain after an ankle arthrodesis. We noted low revision rates and few complications at 1 year.

Radiographic and Clinical Outcomes of the Salto Talaris Total Ankle Arthroplasty

2020 ◽  
Vol 41 (12) ◽  
pp. 1519-1528
Author(s):  
Jonathan Day ◽  
Jaeyoung Kim ◽  
Martin J. O’Malley ◽  
Constantine A. Demetracopoulos ◽  
Jonathan Garfinkel ◽  
...  
Keyword(s):  
Clinical Outcomes ◽  
Case Series ◽  
Total Ankle Arthroplasty ◽  
Retrospective Case ◽  
Level Of Evidence ◽  
Ankle Arthroplasty ◽  
Patient Reported ◽  
The Mean ◽  
Component Revision

Background: The Salto Talaris is a fixed-bearing implant first approved in the US in 2006. While early surgical outcomes have been promising, mid- to long-term survivorship data are limited. The aim of this study was to present the survivorship and causes of failure of the Salto Talaris implant, with functional and radiographic outcomes. Methods: Eighty-seven prospectively followed patients who underwent total ankle arthroplasty with the Salto Talaris between 2007 and 2015 at our institution were retrospectively identified. Of these, 82 patients (85 ankles) had a minimum follow-up of 5 (mean, 7.1; range, 5-12) years. The mean age was 63.5 (range, 42-82) years and the mean body mass index was 28.1 (range, 17.9-41.2) kg/m2. Survivorship was determined by incidence of revision, defined as removal/exchange of a metal component. Preoperative, immediate, and minimum 5-year postoperative AP and lateral weightbearing radiographs were reviewed; tibiotalar alignment (TTA) and the medial distal tibial angle (MDTA) were measured to assess coronal talar and tibial alignment, respectively. The sagittal tibial angle (STA) was measured; the talar inclination angle (TIA) was measured to evaluate for radiographic subsidence of the implant, defined as a change in TIA of 5 degrees or more from the immediately to the latest postoperative lateral radiograph. The locations of periprosthetic cysts were documented. Preoperative and minimum 5-year postoperative Foot and Ankle Outcome Score (FAOS) subscales were compared. Results: Survivorship was 97.6% with 2 revisions. One patient underwent tibial and talar component revision for varus malalignment of the ankle; another underwent talar component revision for aseptic loosening and subsidence. The rate of other reoperations was 21.2% ( n = 18), with the main reoperation being exostectomy with debridement for ankle impingement ( n = 12). At final follow-up, the average TTA improved 4.4 (± 3.8) degrees, the average MDTA improved 3.4 (± 2.6) degrees, and the average STA improved 5.3 (± 4.5) degrees. Periprosthetic cysts were observed in 18 patients, and there was no radiographic subsidence. All FAOS subscales demonstrated significant improvement at final follow-up. Conclusions: We found the Salto Talaris implant to be durable, consistent with previous studies of shorter follow-up lengths. We observed significant improvement in radiographic alignment as well as patient-reported clinical outcomes at a minimum 5-year follow-up. Level of Evidence: Level IV, retrospective case series.

Comparison of Intermediate-term Outcomes of Total Ankle Arthroplasty in Primary and Ligamentous Post-traumatic Osteoarthritis

2019 ◽  
Vol 40 (11) ◽  
pp. 1273-1281 ◽  
Author(s):  
Gun-Woo Lee ◽  
Asep Santoso ◽  
Keun-Bae Lee
Keyword(s):  
Short Form ◽  
Total Ankle Arthroplasty ◽  
Level Of Evidence ◽  
Ankle Arthroplasty ◽  
Radiographic Outcomes ◽  
Primary Osteoarthritis ◽  
Post Traumatic ◽  
American Orthopaedic ◽  
End Stage

Background: Ankle ligamentous injuries without fracture can result in end-stage ligamentous post-traumatic osteoarthritis, which may cause ligamentous imbalance after total ankle arthroplasty (TAA). However, outcomes of TAA in these patients are not well known. The purpose of this study was to evaluate intermediate-term clinical and radiographic outcomes of TAA in patients with ligamentous post-traumatic osteoarthritis and compare them with results of TAA for patients with primary osteoarthritis. Methods: We enrolled 114 patients (119 ankles) with consecutive primary TAA using HINTEGRA prosthesis at a mean follow-up duration of 6.0 years (range, 3-13). We divided all patients into 2 groups according to the etiology of osteoarthritis: (1) primary osteoarthritis group (69 ankles) and (2) ligamentous post-traumatic osteoarthritis group (50 ankles). Results: There was no significant intergroup difference in mean Ankle Osteoarthritis Scale (AOS), American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, Short Form-36 Physical Component Summary, visual analog scale pain score, ankle range of motion, or complications at the final follow-up. However, the final tibiotalar angle was less corrected to 4.2 degrees in the ligamentous post-traumatic osteoarthritis group compared to 2.7 degrees in the primary osteoarthritis group ( P = .001). More concomitant procedures were required at the index surgery for the ligamentous post-traumatic osteoarthritis group ( P = .001). The estimated 5-year survivorship was 93.4% (primary osteoarthritis group: 91.3%; ligamentous post-traumatic osteoarthritis group: 95.8%). Conclusions: Clinical outcomes, complication rate, and 5-year survivorship of TAA in ankles with primary and ligamentous post-traumatic osteoarthritis were comparable with intermediate-term follow-up. Our results suggest that TAA would be a reliable treatment in ankles with ligamentous post-traumatic osteoarthritis when neutrally aligned stable ankles are achieved postoperatively. Level of Evidence: Level III, retrospective cohort study.

scholarly journals A Comparison of Cyst Formation and Management in Mobile-Bearing and Fixed-Bearing Total Ankle Arthroplasty

2019 ◽  
Vol 4 (2) ◽  
pp. 2473011419S0000
Author(s):  
James Lachman ◽  
Michel Taylor ◽  
Elizabeth Cody ◽  
Daniel Scott ◽  
James A. Nunley ◽  
...  
Keyword(s):  
Bone Grafting ◽  
Patient Reported Outcomes ◽  
Mobile Bearing ◽  
Cyst Formation ◽  
Total Ankle Arthroplasty ◽  
Fixed Bearing ◽  
Ankle Arthroplasty ◽  
Ankle Replacement ◽  
Patient Reported

Category: Ankle Arthritis Introduction/Purpose: The Scandinavian Total Ankle Replacement(STAR) system and Salto Talaris(ST) total ankle system are two of the more commonly studied total ankle implants. As the STAR is one of the oldest total ankle arthroplasty (TAA) implants still in use today, most studies focus on longevity and survivorship. Reported rates of cyst formation for these two prosthesis in most series vary from 11-22% but no large study has focused on surgical management of these cysts or included patient reported outcomes after surgery. In this series, we aimed to investigate rates of cyst formation between mobile(MB) and fixed-bearing(FB) TAA and examine clinical and patient reported outcomes of bone grafting or cementing of large cysts surrounding the STAR and ST implants. Methods: A prospectively collected database at a high volume total ankle replacement center was retrospectively reviewed to identify patients who underwent TAA with either the STAR or the ST total ankle system between 2007 and 2015. Cysts were identified and measured on standard weight bearing radiographs and confirmed on computed tomography(CT) when available. Visual analog scale (VAS) score, Short Form-36 (SF-36) physical and mental component scores, Short Musculoskeletal Function Assessment(SMFA), and AOFAS hindfoot scores were collected from all patients preoperatively and then at 6 months, 1 year and annually postoperatively. Patients with a minimum 2 years follow-up who underwent revision TAA secondary to catastrophic bone cysts or who were managed with either curettage and bone grafting or curettage and cementing of bone cysts surrounding the TAA prosthesis were included in the patient reported outcomes (PRO) analysis Results: Excluding 53 patients for inadequate follow-up, 232 patients (29% female, 71% male; follow-up 6.7 years) who underwent STAR-TAA and 147 patients (26.6% female, 73.5% male; follow-up 7 years) who underwent ST-TAA were identified. Cysts <20 mm diameter occurred more often in the MB TAAs, and more often in the tibia than talus (table). Cysts >10 mm were identified in 95/232 (41%) STAR and 24/147 (16%) ST ankles. In the STAR group, 24 patients underwent cyst bone grafting (13), cementing (6) or both (8) at a mean 4.8 years. In the ST group, 14 patients underwent cyst bone grafting (6), cementing (4), or both (4) at a mean of 2.7 years. PRO data improved significantly for both the STAR and ST group in all questionnaires (p<0.05 for all). Conclusion: Mobile-bearing total ankle arthroplasty in this cohort had a higher rate of cyst formation greater than 10 mm (95/232 patients, 41%) when compared to a fixed-bearing TAA (24/147, 16.3%). Only 24/95 (25%) of STAR patients and 14/24 (58%) of ST patients required surgical intervention for cyst management. Patient reported outcomes after cyst surgery improved significantly when compared to pre-cyst management surgery and did not differ between MB and FB cohorts (p=0.424). Successful surgical management of large cyst surrounding either mobile-bearing or fixed-bearing total ankle systems can be expected based on the results of this study. [Table: see text]

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