Reliability analysis of WBCT-derived 3D models for comparing preoperative and postoperative alignment in total ankle arthroplasty.

BACKGROUND: Traditional imaging techniques for total ankle arthroplasty (TAA) evaluation are limited by rotational bias and bone superimposition, highlighting the necessity for more precise assessment methods. The advent of weight-bearing computed tomography (WBCT) generated 3D enhance the visualization of foot and ankle alignment, offering unmatched detail. This study aims to assess the accuracy of preoperative and postoperative measurements in TAA across all three planes using WBCT-generated 3D models. We hypothesize that these models can be reliably used to compare preoperative and postoperative alignment. METHODS: For 81 patients undergoing TAA, preoperative and postoperative WBCT models were created. Measurements included five coronal angles: Alpha, Tibiotalar Surface Angle (TSA), Talar Tilt Angle (TT), Salzmann's 20 degrees Angle (SA), and Talocalcaneal Angle (TCA); three sagittal angles: Beta, Gamma, and Tibiotalar Ratio (TTR); and one axial angle: The Posterior Talar Rotational Angle (PTARA). Two raters evaluated these before and after surgery in two separate sessions. The study then compared preoperative to postoperative measurements, calculating inter-rater and intra-rater reliability. RESULTS: Significant changes were observed in three coronal angles (TSA, TT, and SA) and two sagittal angles (Beta and Gamma), with P-values of 0.2, 0.007, 0.019, <0.001, and <0.001, respectively. No significant changes were noted in Alpha, TCA, TTR, and PTARA, with P-values of 0.2, 0.9, 0.2, and 0.6, respectively. Intra-rater and inter-rater reliability scores ranged from 0.885 to 0.97, indicating good to excellent interclass correlation across all planes, both pre-and postoperatively. CONCLUSION: WBCT-generated 3D modeling and image analysis software have enabled a detailed comparison between preoperative alignment and postoperative TAA positioning across coronal, sagittal, and axial planes, revealing significant adjustments in coronal and sagittal alignments. The high reliability and reproducibility of these measurements affirm their value in preoperative planning in improving the accuracy of surgical interventions. LEVEL OF EVIDENCE: Level III of evidence.

Avascular Necrosis of the Talus: Diagnosis, Treatment, and Modern Reconstructive Options.

Talar avascular necrosis (AVN) is a devastating condition that frequently follows type III and IV talar neck fractures. As 60% of the talus is covered by hyaline cartilage, its vascular supply is limited and prone to trauma, which may eventually lead to AVN development. Early detection of AVN (Hawkins sign, MRI) is crucial, as it may prevent the development of the irreversible stages III and IV of AVN. Alertness is advised regarding non-obvious conditions that may cause this complication (sub chondroplasty, systemic lupus erythematosus, diabetes mellitus). Although, in stages I-II, AVN may be treated with non-surgical procedures (ESWT therapy, non-weight bearing) or joint-sparing techniques (core drilling, bone marrow aspirate injections), stages III-IV require more advanced procedures, such as joint-sacrificing procedures (hindfoot arthrodesis/ankle arthrodesis), or replacement surgery, including total talar replacement (TTR) or combined total ankle replacement (TAR). The advancement of 3D-printing technology and increased access to implant manufacturing are contributing to a rise in the production rates of third-generation total talar prostheses. As a result, there is a growing frequency of alloplasty procedures and combined total ankle replacement (TAR) surgeries. By performing TTR as opposed to deses, the operator avoids (i) delayed union, (ii) a shortening of the limb, (iii) a lack of mobility, and (iv) the stiffening of adjacent joints, which are the main disadvantages of joint-sacrificing procedures. Simultaneously, TTR and combined TAR offer (i) a brief period of weight-bearing restriction, (ii) quick pain relief, and (iii) preservation of the length of the limb. Here, we summarize the most up-to-date knowledge regarding AVN diagnosis and treatment, with a special focus on the role of TTR.

Influence of Tibial Component Design Features and Interference Fit on Implant-Bone Micromotion in Total Ankle Replacement: A Finite Element Study.

BACKGROUND: Implant survivorship in uncemented total ankle replacement (TAR) is dependent on achieving initial stability. This is because early micromotion between the implant and bone can disrupt the process of osseointegration, leading to poor long-term outcomes. Tibial implant fixation features are designed to resist micromotion, aided by bony sidewall retention and interference fit. The goal of this study was to investigate design-specific factors influencing implant-bone micromotion in TAR tibial components with interference fit. METHODS: Three implant designs with fixation features representative of current TAR tibial components (ARC, SPIKES, KEEL) were virtually inserted into models of the distal tibias of 2 patients with end-stage ankle arthritis. Tibia models were generated from deidentified patient computed tomography scans, with material properties for modeling bone behavior and compaction during press-fit. Finite element analysis (FEA) was used to simulate 2 fixation configurations: (1) no sidewalls or interference fit, and (2) sidewalls with interference fit. Load profiles representing the stance phase of gait were applied to the models, and implant-bone micromotions were computed from FEA output. RESULTS: Sidewalls and interference fit substantially influenced implant-bone micromotions across all designs studied. When sidewalls and interference fit were modeled, average micromotions were less than 11 µm, consistent across the stance phase of gait. Without sidewalls or interference fit, micromotions were largest near either heel strike or toe-off. In the absence of sidewalls and interference fit, the amount of micromotion generally aligned inversely with the size of implant fixation features; the ARC design had the largest micromotion (~540 µm average), whereas the KEEL design had the smallest micromotion (~15 µm). CONCLUSION: This study presents new insights into the effect of TAR fixation features on implant-bone micromotion. With sidewalls and interference fit, micromotion is predicted to be minimal for implants, whereas with no sidewalls and no interference fit, micromotion depended primarily on the implant design. CLINICAL RELEVANCE: This study presents new insights into the effect of TAR primary fixation features on implant-bone micromotion. Although design features heavily influenced implant stability in the model, their influence was greatly diminished when interference fit was introduced. The results of this study show the relative importance of design features and interference fit in the predicted initial stability of uncemented TAR, potentially a key factor in implant survivorship.

Placing the tibial component of an ankle prosthesis: results of a CT-based simulation in healthy adults.

PURPOSE: To characterize the 3D geometry of the distal tibia resection area from healthy individuals using CT-based digital implantation for proper preoperative sizing of TAA tibia component placement. METHODS: Standardized CT images of healthy ankle joints serving as intra-individual references for treatment of contralateral injuries were identified. The tibial cross section dedicated to virtually host the tibial component was digitally prepared, and the size of the virtual contact surface was calculated. Finally, out of five prototypes the one fitting best in terms of size and alignment was identified. RESULTS: CT scans taken from 319 subjects were used for the virtual implantation procedure. Body height and size of the distal tibia contact area correlated (r = 0.49 and 0.42 in females and males, each p < 0.001). Prosthesis sizes 2 and 3 fit well for the vast majority of patients, while the smallest and largest sizes are rarely required. CONCLUSIONS: Digital implantation of the tibial component should be considered a valuable tool for preoperative planning as well as for the development of new implant types.

Total Ankle Arthroplasty as a Correction Tool for Foot Deformities: Analyzing the Impact on Medial Column Alignment Adaptation Through Weightbearing Computed Tomography.

BACKGROUND: While weightbearing computed tomography (WBCT) has been instrumental in analyzing total ankle arthroplasty (TAA) positioning, there is a notable gap in the literature regarding adaptive changes in the foot's medial column after TAA. This study aims to bridge this gap by comparing preoperative and postoperative alignments of the foot's medial column and analyzing if a correlation exists between TAA coronal alignment correction and medial column alignment adaptation. METHODS: Sixty patients who underwent a lateral approach TAA for end-stage osteoarthritis (OA) between January 2021 and April 2023 were included in this retrospective study. Patients were divided into varus (n = 30) and valgus (n = 30) groups. Preoperative and postoperative WBCT scans were analyzed to measure medial column alignment. Statistical analysis evaluated alignment corrections and correlations. RESULTS: Both groups showed significant plantarflexion of the second tarsometatarsal (TMT) angle, with a median adaptation of -1 degree (IQR -3, 0; P < .01) in the valgus group and -1 degree (IQR -3, 0; P = .03) in the varus group. The varus group exhibited increased plantarflexion of the first TMT angle (median -1 degree, IQR -1, -2; P = .03). Both groups demonstrated increased adduction of the medial column. The talonavicular coverage angle adaptation averaged 7.2 ± 14 degrees (P < .01) in the valgus and 9 ± 12 degrees (P < .01) in the varus group. The talo-first metatarsal axial angle adaptation was 5 ± 13 degrees (P = .03) in the valgus group and 9.5 ± 15 degrees (P = .08) in the varus group. CONCLUSION: WBCT analysis revealed significant medial column adaptation post-TAA in varus and valgus alignments. However, no correlation was found between hindfoot correction and forefoot adaptation, making it challenging to predict the need for additional realignment surgeries. Future studies should explore the relationship between tibiotalar correction and medial column alignment to improve outcomes and the influence of total ankle design on medial column adaptation. LEVEL OF EVIDENCE: Level III, retrospective case control study.

Total ankle/total talus replacement - Retrospective comparison of surgeon decision relative to three-dimensional joint health assessment.

Treatment of end-stage ankle conditions is a complex challenge in foot and ankle surgery. The talus is prone to issues such as osteoarthritis (OA) and avascular necrosis (AVN). Patient-specific total ankle and total talus replacement (TATTR) procedures have emerged as potential solutions, but the decision to include subtalar arthrodesis in these surgeries is multifaceted. In this study, we aimed to understand the relationship between past surgeon decisions for fusion with TATTR and three-dimensional joint health assessments using preoperative CT data. Twenty-seven TATTR with subtalar fusion and 19 TATTR without subtalar fusion were analyzed. Each patient underwent a bilateral computed tomography scan, which was segmented prior to surgery. Distance mapping of various subtalar regions was performed, and average distance was reported. For better analysis, the sinus tarsi was divided into four sectors and the calcaneus posterior facet into nine sectors. Statistical analysis involved calculating the difference in means between the fused and unfused cases. The fusion group exhibited significant joint space narrowing in the posterolateral aspect of the sinus tarsi (p = 0.021). Conversely, on the posterior facet of the subtalar joint, the fusion group showed significant joint space widening in both the anteromedial (p = 0.025) and middle/medial (p = 0.032) sections. Surgeons' decision to perform subtalar arthrodesis in TATTR procedures often aligns with clinical signs of sinus tarsi impingement, as evidenced by significant changes in joint space measurements. While joint health assessments play a pivotal role, other factors, such as surgeon preference and patient-specific considerations, also influence decision-making.

Younger age correlates with increased gutter impingement rates after total ankle arthroplasty.

BACKGROUND: While total ankle arthroplasty (TAA) has evolved over the years with improved designs and enhanced bony fixation methods, it remains a technically demanding procedure with a risk of early postoperative complications. One of the most common complications associated with TAA is medial and lateral gutter ankle impingement, which can lead to issues such as increased pain and decreased range of motion (ROM). However, there is a paucity of information in the literature discussing the impact of certain risk factors on gutter impingement complications. METHODS: A retrospective analysis was conducted on a cohort of patients who underwent a TAA at a single institution from 2003 to 2019 with a minimum of 2-year follow-up. Patient were identified as having gutter impingement based on diagnostic imaging and/or clinical examination. Data collection included demographics, implant type, follow-up time, and co-morbidities. Multivariate odds ratios (OR) of experiencing gutter impingement were calculated for perioperative variables. RESULTS: The study included a total of 908 patients who underwent TAA with a minimum of 2 year follow up and 121 patients (13.3 %) who subsequently experienced gutter impingement. The average follow-up time was 5.84 + /- 3.07 years. There were 178 patients under 55 years old, 495 patients aged 55 to 70, and 235 patients over 70 years old. A higher rate of gutter impingement was observed in patients under 55 years of age compared to those aged 55 to 70 and over 70 (20.8 % vs. 13.5 % vs. 7.2 %; p < 0.01). Multivariable logistic regression revealed that patient age was significantly correlated with gutter impingement following TAA, with an OR of 0.94 (CI: 0.91-0.98; p < 0.01). CONCLUSION: This study demonstrated increased incidence of gutter impingement in younger patients who underwent TAA. Propensity for scar tissue formation may be higher in this population. Scar tissue deposition following TAA can cause narrowing of the medial and lateral clear spaces, potentially leading to gutter impingement. Additionally, younger patients may have increased activity demands, which subsequently may cause higher rates of symptomatic impingement. As increased impingement after TAA may require the need for additional debridement surgeries, it is important to understand the intricate relationship between age and gutter impingement for managing patient expectations following TAA. LEVEL OF EVIDENCE: Level III.

SPECT/CT of Total Ankle Arthroplasty.

Use of SPECT/CT (Single Photon Emission Computed Tomography/Computed Tomography) is increasing providing additional information in patients with inconclusive clinical examination and unremarkable imaging findings presenting with chronic pain after total ankle arthroplasty. To differentiate the cause of pain after total ankle arthroplasty can be challenging. SPECT/CT combines structural and metabolic imaging as a hybrid tool leading to higher specificity and overall diagnostic accuracy presumably in cases of gutter impingement, prosthetic loosening, and osteoarthritis of adjacent joints. Moreover, SPECT/CT can complement diagnostic work up in periprosthetic joint infections. Basal tracer enhancement has to be considered for the interpretation of imaging findings.

Total ankle replacement: Implant Manufacturer's guidelines for post-operative rehabilitation: A review of literature.

Introduction: Total ankle replacements (TARs) is emerging as a successful alternate treatment option to arthrodesis for surgical treatment of end stage ankle arthritis. This has led to manufacturers producing a selection of implants. There is wide variations in post-operative rehab protocols being adopted for treatment following TAR surgery. This depends on choice of implants and manufacturer recommendations too. Following the author's investigation, a lack of standardisation between manufacturer post-operative protocols was identified. The aim of this project was to analyse similarities and differences in guidelines for: choice of immobilisation, weight-bearing (WB) status, of range of movement (ROM) exercises and Physiotherapy. Method: Current commonly used TAR implants in the UK were identified using National Joint Registry's 2020 Annual Report. Additional implants were included after accessing data regarding the TAR market. Individual company websites were researched for information available on public domain for post op management guidelines and the results were summarised. Results: Only 7 implants were reviewed as 6 companies either did not provide post-operative protocols or recommended a surgeon guided rehabilitation process. Different manufacturers allow partial WB by week 2, week 3 and week 7. One protocol suggested full WB from week 4 whereas two others suggested it from week 6. Choices of immobilisation varied as one company suggested casting alone for 6 weeks, two suggest casting followed by a period in a boot, one suggests splinting and a boot and one uses all 3 types of immobilisations. ROM exercises were mentioned by three manufacturers and were encouraged from week 2 and 3. Physiotherapy was mentioned in four protocols, two of which suggest intervention from week 6, one from week 7 and the other mentions the importance of therapy rather than specific timelines. Conclusion: There are differences between post op TAR guidelines from the implant manufacturers regarding the categories analysed. The variation in the data collected makes it challenging to suggest a singular protocol to be followed after TAR surgery.

Traumatic Periprosthetic Fractures Following Total Ankle Replacement A Systematic Review and Proposed Classification.

Total ankle replacements (TAR) are increasingly utilized, but postoperative traumatic periprosthetic fractures remain a rare yet challenging complication. This systematic review aims to address the gap in literature by proposing a comprehensive classification system for these fractures, considering implant stability, fracture location, and surrounding bone quality. A systematic review identified 13 cases from 9 studies meeting inclusion criteria. Fractures were categorized using the proposed Hill-Brown classification: Type A (talus or fibula), Type B (distal tibial component), and Type C (diaphysis/proximal tibial metaphysis). Implant stability was a key factor, with Type B fractures further classified as B1 (stable), B2 (unstable with adequate bone stock), and B3 (unstable with poor bone stock). Most fractures occurred at or near the distal tibial component (Type B), with implant stability largely dependent on fracture location and bone quality. Surgical fixation, particularly minimally invasive plate osteosynthesis (MIPO) with locking plates, was the preferred treatment for stable implants, showing low complication rates. Unstable implants often required revision TAR or conversion to arthrodesis. Surgical intervention is recommended following all traumatic periprosthetic fractures in the setting of a TAR. Bone quality, particularly in patients with rheumatoid arthritis or osteoporosis, significantly impacted treatment decisions. Our findings emphasize the importance of fracture location, implant stability, and bone quality in managing these fractures. Future multicenter studies are necessary to validate this classification system and refine treatment protocols.Level of Evidence: Level III.

Age Influence on Total Ankle Arthroplasty Outcomes: A Systematic Review.

Total ankle arthroplasty has gained popularity as advancing technology has resulted in higher survivorship and lower complication rates. In the past, total ankle replacement candidates have been reserved for patients greater than 50 years old with low physical demands and minimal deformity. However, with newer designs, surgeons have begun to expand their patient inclusion criteria. The purpose of this study was to analyze current literature comparing patient outcomes among total ankle replacement patients over and under age 50. A systematic review of the literature was performed comparing the impact of age to total ankle replacement outcomes. 159 articles were reviewed. Seven studies met our inclusion criteria and therefore were included in the synthesis. No statistically significant difference in outcomes was determined for the younger and older age groups in regard to reoperation, complications, and implant survivorship (p = .412, .955, .155, respectively). However, the statistical model is underpowered given the limited number of studies. While the findings of this study infer that total ankle replacement outcomes are not significantly different among older and younger age groups, further research in this area is needed.

Radiological Landmarks for Joint Line Level in Challenging Total Ankle Arthroplasty.

Background: Although Total Ankle Arthroplasty (TAA) is primarily performed for post-traumatic ankle arthritis with joint disruption, anatomical landmarks for Joint Line (JL) level are typically preserved. However, severe Post-Traumatic Bone Loss (PTBL) or TAA revision may render some landmarks unidentifiable, challenging JL restoration. Methods: Patients undergoing customized TAA for severe PTBL or revision were enrolled. Custom-made implants, based on 3D CT scans, were designed to address bone defects and provide adequate bone support. Evaluated parameters, measured on bilateral ankle weight-bearing radiographs taken preoperatively and 6-8 months postoperatively, included JL Height Ratio (JLHR) and the distances from JL to the Lateral Malleolus apex (LM-JL), the posterior colliculus of the Medial Malleolus (MM-JL), and the Gissane Calcaneal Sulcus (CS-JL). Reproducibility and variability were assessed, and comparisons were made between radiological parameters measured at TAA and those at the contralateral ankle. Results: Thirteen patients were included. Intra- and interobserver reliability demonstrated excellent values. The least variability was observed in the LM-JL distance. Statistically significant correlations were found between CS-JL and MM-JL distances in the operated limb and between the CS-JL of the operated limb and the contralateral ankle. While TAA parameters did not show statistically significant differences compared with the contralateral ankle, a trend toward proximalization of the JL was noted. Conclusions: This study demonstrated good reproducibility of the analyzed parameters for evaluating JL in TAA among patients with severe PTBL or undergoing revision surgery. However, these parameters cannot be deemed fully reliable. Given their potential weaknesses, it is crucial to identify more reproducible values, preferably ratios.

What is the Total Ankle Arthroplasty Experience of Podiatric Foot and Ankle Surgery Fellows? A National Survey.

In 2011, the Council of Podiatric Medical Education, the accrediting body of the American Podiatric Medical Association, approved the conversion of all Podiatric Residencies to 3-year surgical programs. In 2012, there were 12 podiatric fellowships recognized by the American College of Foot and Ankle Surgeons. To date, there are 53 programs listed under the college's website. As podiatric fellowships expand, further research is needed to identify advantages and pitfalls of fellowship training. Our primary aim was to obtain current fellow survey data to enhance our understanding of podiatric reconstructive foot and ankle surgery fellowship training programs. In doing so, we decided to use one of the most salient topics in fellowship training- Total Ankle Replacement. Invitation was administered by email and 73.6% of active reconstructive 2023-24 American College of Foot and Ankle Surgeons postgraduate fellows responded. Fellowship total ankle replacement case volume was significantly greater than residency (p = 0.037). Completion of 0-5 total ankle replacement(s) was 30.8%, and greater than 30 in 17.9% of fellows. Fifty nine percent reported feeling "comfortable" or "very comfortable" with total ankle arthroplasty. Patient specific instrumentation was used in a majority of cases (66.7%). Over three fourths (79.8%) of fellows stated they planned on performing TAR as an attending surgeon after their fellowship. Despite its limitations, we hope our survey data can aid graduating and previous fellows and add to the body of knowledge for future TAR educational programs and industry involvement. As podiatric fellowships continue to transform, so too must our research efforts to track progress.

Outcomes of Total Ankle Replacement.

Total ankle replacement (TAR) is an effective operative treatment of end-stage ankle osteoarthritis (OA) in the appropriate patient, conferring improved kinematic function, decreased stress across adjacent joints, and offering equivalent pain relief in comparison to ankle arthrodesis (AA). It is important to consider patient age, weight, coronal tibiotalar deformity, joint line height, and adjacent joint OA to maximize clinical and patient outcomes. Both mobile-bearing and fixed-bearing implants have demonstrated favorable clinical outcomes, marked improvement in patient-reported outcomes, and good survivorship; however, implant survivorship decreases with longer term follow-up, necessitating constant improvement of primary and revision TAR options.

An evaluation of the total ankle replacement in the modern era: a narrative review.

Background and Objective: Total ankle replacement has become an increasingly popular surgical procedure for treatment of end-stage ankle arthritis. Though ankle arthrodesis has historically been considered the gold standard treatment, advancements in implant design, functional outcomes, and survivorship have made total ankle replacement a compelling alternative. Particularly, in the past 20 years, total ankle replacement has undergone tremendous innovation, and the field of research in this procedure continues to grow. In this review, we aim to summarize the history, evolution, advancements, and future directions of total ankle replacement as described through implant design, indications, surgical procedures, complications, and outcomes. Methods: Literature searches were conducted in PubMed to identify relevant articles published prior to March 2023 using the following keywords: "total ankle replacement", "total ankle arthroplasty", and "total ankle". Key Content and Findings: Total ankle replacement has demonstrated significant improvements in surgical technique, implant design, survivorship, and clinical and functional outcomes in the modern era. The procedure reports high patient satisfaction, low complication rates, and improved functional abilities that challenge the current gold standard treatment for ankle arthritis. Conclusions: Though there are areas of improvement for total ankle replacement, the procedure demonstrates promising outcomes for patients with end-stage ankle arthritis to improve pain and functional abilities. Research studies continue to explore various the facets of total ankle replacement, including outcomes, risk factors, novel techniques and modalities, and complications, to direct future innovation and to optimize patient results.

Five-Year Results of the Salto XT Revision Ankle Arthroplasty.

BACKGROUND: The treatment of failed ankle replacements is debated, and little is published about the medium- and long-term results of revision implants. We wanted to examine prosthesis survival and physical function at least 5 years after insertion of the Salto XT revision prosthesis. METHODS: All consecutive patients operated with a Salto XT revision prosthesis underwent clinical and radiologic examinations preoperatively and after 3, 12, 24, and 60 months. Complications and reoperations are described, and changes in patient-reported outcome measures and clinical scores are reported. RESULTS: Thirty patients were operated with a Salto XT revision prosthesis between March 2014 and March 2017. Three of these were revised (1 to a fusion and 2 to a new prosthesis), and 3 patients were reoperated with screw removal. A concurrent subtalar fusion was performed on 13 patients, and there was 1 case of likely nonunion after these procedures, but no reoperations. The mean AOFAS score increased from 39.2 (95% CI 30.8-47.5) preoperatively to 75.1 (95% CI 67.3-82.9) after 5 years, and the mean improvement was 34.2 points (95% CI 23.8-44.6). Mean EQ-5D increased from 0.36 (95% CI 0.30-0.42) preoperatively to 0.74 (95% CI 0.64-0.85) after 5 years, an improvement of 0.34 (95% CI 0.19-0.49). Radiolucent lines were present in all but 3 patients. Five-year prosthesis survival was 93% (83.6-100). CONCLUSION: This is the first study to present medium-term results of this implant. We found good improvement in outcome scores and good implant survival, but also a high prevalence of radiolucent lines.

Median age of patients undergoing total ankle replacement has not significantly changed between 1999 and 2023: A systematic review of prospective studies.

INTRODUCTION: Total ankle replacement (TAR) is an effective treatment for end-stage osteoarthritis. The aim of this systematic review was to assess the age of patients undergoing TAR in prospective comparative studies. Our hypothesis is that the age reported in most recent papers might be lower than those reported in older papers. METHODS: This systematic review was performed using Pubmed, Scopus, EMBASE and Cochrane databases. Only Level I and II studies dealing with TAR were included. Data regarding demographics, study design, number of cohorts in each study, year of publication and year/years in which surgery was performed were extracted. A two-fold analysis was conducted building groups of patients based on the year of publication and creating 1) two groups (before and after the median year) and 2) three groups (using tertiles) in order to compare age of patients operated in different period of times. A comparison was also performed considering the median year of surgery for patients undergoing TAR. RESULTS: Overall 59 cohorts (42 studies, published between 1999 and 2023; median year of publication: 2017) were included (6397 ankles, 6317 patients, median age 63 years). The difference between the median age for 27 cohorts published until 2016 (weighted median 63 years; IQR, 62.5-64) and the median age for 32 cohorts published after 2017 (weighted median 63.2 years; IQR, 63-67.8) was not statistically significant (p = 0.09). The division in tertiles did not reveal any significant change in the weighted median age at surgery (T1 (1999-2014; 63.2 years; IQR, 62.8-64.1), T2 (2015-2018; 63 years; IQR,63-63.5) and T3 (2019-2023; 63.2 years; IQR, 62.6-67.8)) over time (p = 0.65). The median age of patients operated between 1999 and 2008 vs 2009 and 2023 (data from 48 cohorts) was not different either (p = 0.12). CONCLUSION: According to this review of prospective studies published between 1999 and 2023, the median age for patients undergoing TAR over the last two decades has been 63 years, remaining steady with no significant changes over time. LEVEL OF EVIDENCE: Level II - systematic review including Level I and Level II studies.

The morphometry of distal tibia and posterior malleolus and its clinical implications in total ankle prosthesis.

PURPOSE: The aim of this study is to reveal the morphometry of the distal tibia and posterior malleolus and to generate morphometric reference data for the tibial component of total ankle prosthesis. METHODS: This study was performed on 121 human dry tibiae (47 right, 74 left). The morphometric measurements of distal tibial structures, tibial length and the distance between the medial and posterior malleolus were measured in this study. Measurements on 44 tibiae were repeated three times and averaged for minimizing intra-observer error. RESULTS: The tibial length was found 34.19 ± 2.31 cm. Mean values of width of fibular notch at tibial plafond and 10 mm proximal to the tibial plafond were 25.71 ± 2.44 mm and 17.81 ± 2.46 mm, respectively. Mean depth of fibular notch at tibial plafond and 10 mm proximal to the tibial plafond were 3.60 ± 1.04 mm and 3.37 ± 1.24 mm, respectively. Mean height of fibular notch was found 48.21 ± 10.51 mm. Mean width and height of medial malleolus were 25.08 ± 2.13 mm and 14.73 ± 1.85 mm, respectively. Mean width and length of tibial plafond were 27.71 ± 2.74 mm and 26.96 ± 2.62 mm, respectively. Mean values of width and height of posterior malleolus were measured 21.41 ± 3.26 mm and 6.74 ± 1.56 mm, respectively. Mean distance between medial and posterior malleolus was found 37.17 ± 3.53 mm. Mean width and depth of malleolar groove were 10.26 ± 1.84 mm and 1.73 ± 0.75 mm, respectively. The mean intra-class correlation values were found between the 0.959 and 0.999. CONCLUSIONS: Knowing the distal tibial morphometry is crucial for designing convenient ankle replacement implants for Turkish population. To our knowledge, this study is the first in the literature that identifies posterior malleolar morphometry on dry tibiae. We believe that this study will make a significant contribution to the literature about distal tibial morphometry and especially the posterior malleolus and the data of our study can be used for designing total ankle prosthesis in Turkish population.

Outcome after total ankle replacement or ankle arthrodesis in end-stage ankle osteoarthritis on the basis of german-wide data: a retrospective comparative study over 10 years.

BACKGROUND: In symptomatic end-stage osteoarthritis of the ankle joint, total ankle replacement and ankle arthrodesis are the two primary surgical options for patients for whom conservative treatment fails. Published revision rates are often biased and difficult to compare. In this study, unplanned reoperation rates and revision rates were determined for both surgical interventions based on a large dataset, and risk factors for unplanned reoperations were identified. METHODS: German-wide health data of the largest German health-care insurance carrier between 2001 and 2012 were retrospectively analyzed, and unplanned reoperation rates within 10 years were determined for index surgeries conducted in 2001 and 2002. Unplanned reoperation rates within 5 years for index surgeries conducted in 2001/2002 were compared to index surgeries conducted in 2006/2007. Multivariate logistic regression was used to identify risk factors for unplanned reoperations. RESULTS: After ankle arthrodesis, 19% (95% confidence interval [CI], 16-22%) of 741 patients needed to undergo an unplanned reoperation within ten years. After total ankle replacement, the unplanned reoperation rate was 38% [95% CI, 29-48%] among 172 patients. For initial surgeries conducted at a later date, unplanned reoperation rates within five years were 21% [95% CI, 19-24%] for 1,168 ankle arthrodesis patients and 23% [95% CI, 19-28%] for 561 total ankle replacement patients. Significant risk factors for unplanned reoperations after ankle arthrodesis in the initial cohort were age < 50 years (odds ratio [OR] = 4.65 [95% CI 1.10;19.56]) and osteoporosis (OR = 3.72 [95% CI, 1.06;13.11]); after total ankle replacement, they were osteoporosis (OR = 2.96 [95% CI, 1.65;5.31]), Patient Clinical Complexity Level (PCCL) grade 3 (OR = 2.19 [95% CI, 1.19;4.03]), PCCL grade 4 (OR = 2.51 [95% CI, 1.22;5.17]) and diabetes mellitus (OR = 2.48 [95% CI, 1.33;4.66]). Kaplan-Meier analyses including 1,525 ankle arthrodesis patients and 644 total ankle replacement patients revealed an average unplanned reoperation-free time of approximately 17 years for both procedures. CONCLUSIONS: Similar revision rates and unplanned reoperation rates for both procedures in the later-date cohort can likely be attributed to a learning curve for surgeons as well as advances in implant design. This analysis of billing health insurance data supports an increase in total ankle replacement surgeries.

Analyzing Learning Curve Effects: Total Ankle Replacement Design Switch and Long-Term Survival.

Different aspects of the learning curve in total ankle replacement (TAR) have been studied in the short to mid-term, with 30 cases often considered critical. However, its impact on long-term (10- and 15-year) survival remains unclear. Therefore, we retrospectively analyzed 77 consecutive TARs performed by one orthopedic surgeon. The main outcome was long-term survival between cases 1-30 and 31-77 using the Kaplan-Meier with Competing Risk Analyses. Secondarily, we used Moving Average Method with LOESS regression to confirm the learning curve based on the perioperative complications. Thirdly, associations between perioperative complications and operation time on long-term survival were assessed using Cox proportional hazard models. The 10-year survival of cases 1-30 was 89.9% (95% CI 70.4-96.5), and of 31-77, 92.4% (95% CI 7745- 97.5) (p = .58). The 15-year survival was 81.8% (95% CI 59.5-91.8) and 74.8% (95% CI 52.4-86.6), respectively (p = .97). The long-term survival rate for the TAR that endured perioperative complication was 96.70% (95% CI 90.28-103.12), and for the uncomplicated TAR 87.50% (95% CI 77.12-97.88%) (p = .24). Operating time nor occurrence of perioperative fractures were significantly associated with long-term survival (p = .11 and 0.26, respectively). However, moving average method revealed a significant decreasing trend with a cut-off value of 33 procedures regarding the marginal probability of perioperative osseous complications (p < .01). In conclusion, surgeons should note a learning curve when adapting arthroplasty procedures. After the prosthesis design switch, the learning curve regarding perioperative osseous complications was confirmed at 33 TAR. The switch did not affect long-term survival.