Comparison of practice patterns in total ankle replacement and ankle fusion in the United States

[Arthroscopically assisted arthrodesis of the upper ankle joint]

OBJECTIVE

To obtain a pain-free, fully weight-bearing ankle joint in a functional position through minimally invasive arthrodesis.

INDICATIONS

Symptomatic osteoarthritis of the upper ankle joint, which is no longer treatable conservatively or by joint-preserving surgical procedures.

CONTRAINDICATIONS

Revision arthrodesis, infections in the surgical area, circulatory disorders; extensive malalignment, large bony defects (relative contraindications).

SURGICAL TECHNIQUE

Anteromedial and anterolateral standard portal to the upper ankle joint. Soft tissue debridement and, if necessary, removal of large ventral osteophytes and free joint bodies. Removal of the remaining tibiotalar articular cartilage using curettes, sharp spoons, chisels, or reamers. Opening of the subchondral bone with bone awls or chisels to expose the former joint surfaces. Anatomical adjustment of the joint, transfixation with 2 to 3 Kirschner wires for percutaneous stabilization with cannulated double-threaded screws or cancellous bone screws with short threads under X‑ray control.

POSTOPERATIVE MANAGEMENT

Postoperative immobilization in an orthosis or plaster cast with unloading for 6 weeks; after X‑ray control, gradual increase in weight-bearing over a further 2-6 weeks.

RESULTS

In all, 30 arthroscopically assisted arthrodeses of the ankle joint performed between 2014 and 2017 were retrospectively evaluated. Of these, 22 patients were very satisfied, 5 patients were satisfied, and only 2 patients were not satisfied with the surgical outcome. The evaluation using postoperative scores (American Orthopaedic Foot and Ankle Society Score [AOFAS], Foot and Ankle Outcome Score [FAOS], Visual Analogue Scale Foot and Ankle [VAS-FA]) also yielded good results on average. The complication rates were comparable to those in the literature, with 2 pseudarthroses, 3 superficial wound healing disorders, and 2 irritations caused by the osteosynthesis material.

Distal tibial osteophytes are more accurate than medial malleolar anatomy when using patient specific instrumentation in total ankle replacement

Total ankle replacement (TAR) is a treatment for end stage ankle arthritis. Patient specific instrumentation (PSI) has been used and shown to allow for accurate placement and alignment in TAR in the coronal and sagittal plane. PSI systems are available and use different anatomic landmarks for the cutting guides. This is a retrospective matched case control study comparing accuracy in alignment using 2 different PSI systems. The case series uses a medial malleolar landmark (MM Group), and each case patient was matched based on preoperative coronal plane alignment with 2 ankles in the control series using the distal tibial osteophytes as landmarks (DT Group), as this system has been in use and studied more. A total of 48 ankles were studied, 16 in the MM Group and 32 in the DT Group matched by coronal plane alignment. There was a difference in accuracy of postoperative coronal plane alignment, with the MM Group deviated from expected by 1.6° ± 1.3° compared to the DT Group at 1.1° ± 0.6°, p = 0.04. This corresponded to 68.8 % of MM Group ankles being within 2° of expected compared to 93.4 % of DT Group ankles. There was no statistically significant difference in sagittal plane alignment between the groups, p = 0.57. Procedure time was the only other statistically significant difference with the MM Group taking longer than the DT Group, 97.4 min and 80.6 min, respectively, p = 0.04. While both groups show good accuracy, alignment based on the distal tibial osteophytes is more accurate than using the medial malleolus.

Dynamic subtalar joint space measurement analysis following tibiotalar arthrodesis and total ankle replacement

BACKGROUND

Tibiotalar arthrodesis and total ankle replacement are current standards for treating end-stage ankle osteoarthritis. Our clinical understanding of biomechanical causes and risk factors for subtalar secondary osteoarthritis development following surgical treatment is limited. The objective of this retrospective study was to investigate subchondral bone morphometric differences of individuals treated with a tibiotalar arthrodesis or ankle arthroplasty that may influence subtalar joint measurements during overground walking; results were compared between surgical groups, their unaffected limb, and asymptomatic controls.

METHODS

Previously collected kinematics were used to measure and compare subtalar joint space and congruence throughout the dynamic activity utilizing a correspondence-based joint measurement analysis. A morphometric analysis evaluated subchondral bone differences of the calcaneus subtalar joint between groups.

FINDINGS

The affected subtalar joint of arthrodesis participants showed increased joint space distance in the medial facet during early stance that was related to kinematic differences compared to controls and their contralateral untreated limbs. Our morphometric analyses demonstrated subchondral bone asymmetries in both surgical groups compared to their contralateral untreated limbs.

INTERPRETATION

Previously reported kinematic differences between treated and untreated limbs in arthrodesis participants may translate to the variations in joint space and morphology observed in this study. Our earlier findings within the arthroplasty group indicated no significant kinematic differences between treated and untreated limbs, and the current study showed minimal significant differences in joint space distances. Collectively, this suggests that arthroplasty joint space and subchondral bone shapes are not as strongly influenced by functional asymmetries as those in the arthrodesis group.

Short-term Adverse Events Following Ankle Arthroplasty and Ankle Arthrodesis A Matched Analysis of Recent Nationally Representative Data

BACKGROUND

Surgical management of ankle osteoarthritis (AOA) includes Ankle Arthrodesis (AA) or Total Ankle Arthroplasty (TAA). The purpose of this study was to analyze data from the National Surgical Quality Improvement Project (NSQIP) to elucidate differences in outcomes between TAA and AA.

METHODS

Patients who underwent TAA or AA from January 2010 to December 2020 were included in this analysis. Matched cohorts were created using 1:1 propensity score matching to match patients according to patient demographics. Independent sample t-tests and chi-square tests were used to determine whether there was a difference between groups. A binary logistic regression was performed to determine the odds ratio (OR) and 95% confidence intervals for any adverse event as related to patient demographics and comorbidities.

RESULTS

There were 2,053 TAA and 359 AA in the unmatched cohorts. The matched cohorts included 359 patients in each group. In the matched cohorts, there was an increase in transfusions, urinary tract infection (UTI), and return to the operating room in the arthrodesis group compared with the arthroplasty group (1.95%, 0.28%, P = .038; 1.11%, 0.00%, P = .045, 3.90%, 1.11%, P = .017). The logistic regression revealed that length of hospital stay (OR = 1.157) and insulin-dependent diabetes (OR = 6.043) had an increased risk of any adverse event for TAA or AA.

CONCLUSION

Identification of complication rates and patient risk factors for adverse events after TAA and AA can assist surgeons and patients in their choice of treatment for AOA.

LEVELS OF EVIDENCE

III (retrospective cohort study).

Effect of a compression staple on correction of varus deformity during arthroscopic ankle arthrodesis

BACKGROUND

Arthroscopic ankle arthrodesis (AAA) has become popular because of its higher rate of bone union, lower invasiveness, and shorter hospital stays compared to those of open arthrodesis. However, postoperative malalignment is often observed for severe varus deformity, which can cause nonunion, pain, and adjacent joint arthrosis. A compression staple can provide a persistent, strong compressive force on the bone surface. This study aimed to clarify the difference in alignment correction in AAA by comparing a compression staple and screws fixation with screws-only fixation pre- and postoperatively.

METHODS

Seventy ankles in 67 patients undergoing AAA were retrospectively reviewed. AAA with three screws through the distal tibia was performed in 53 ankles, and 17 ankles underwent AAA with a compression staple and two screws. After the preparation of the joint surface arthroscopically, patients in the S group had three canulated cancellous screws inserted through the medial tibia. Patients in the CS group had a compression staple placed at the lateral aspect of the tibiotalar joint and two screws inserted through the medial side. Clinical scores and pre-and postoperative alignment on plain radiographs were compared between the two procedures.

RESULTS

There were no significant differences in the pre-and postoperative Japanese Society for Surgery of the Foot scale. One ankle in the S group exhibited nonunion. There were no significant differences in talar tilt and tibiotalar angles between the groups. The tibial plafond angle in the CS group was significantly lower than that in the S group (p < 0.05). Postoperatively, talar tilt and tibiotalar angles on the coronal image, and the lateral tibiotalar angle in the CS group were significantly lower than those in the S group (p < 0.05).

CONCLUSION

AAA with a compression staple and two-screw fixations could obtain more optimal alignments than AAA with screw-only fixation, even in cases with severe varus deformity.

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.

Effect of Preoperative Coronal Plane Alignment on Actual Versus Predicted Alignment Using Patient Specific Instrumentation in Total Ankle Replacement

Alignment in total ankle replacement is important for success and implant survival. Recently there has been the introduction and adoption of patient specific instrumentation for implantation in total ankle replacement. Current literature does not evaluate the effect of preoperative deformity on accuracy of patient specific instrumentation. A retrospective radiographic analysis was performed on 97 consecutive patients receiving total ankle replacement with patient specific instrumentation to assess the accuracy and reproducibility of the instrumentation. Subgroup analysis evaluated the effect of preoperative deformity. All surgeries were performed by fellowship trained foot and ankle surgeons without industry ties to the implants used. Preoperative and postoperative films were compared to plans based on computerized tomography scans to assess how closely the plan would be implemented in patients. Overall postoperative coronal plane alignment was within 2° of predicted in 87.6% (85 patients). Similarly, overall postoperative sagittal plane alignment was within 2° of predicted in 88.7% (86 patients). Tibial implant size was accurately predicted in 81.4% (79 patients), and talus implant size was correct in 75.3% (73 patients). Patients with preoperative varus deformity had a higher difference between predicted and actual postoperative alignment compared to valgus deformity (1.1° compared to 0.3°, p = .02). A higher average procedure time was found in varus patients, and more adjunctive procedures were needed in patients with varus or valgus deformity, but these were not significant, p > .5. Surgeons can expect a high degree of accuracy when using patient specific instrumentation overall, but less accurate in varus deformity.

Post-Traumatic Arthritis of the Knee and Ankle

Post-traumatic osteoarthritis (PTOA) occurs following injury to joints. It accounts for approximately 12% of osteoarthritis and has far-reaching effects on individual patients and social/health care systems. Present work focuses on evaluating the role of the post-traumatic inflammatory response in the development and progression of the disease. As there is minimal evidence to suggest the capacity of cartilage to undergo self-healing, most of this work focuses strictly on the avoidance or prevention of PTOA as opposed to treatment solutions following its onset. Ongoing and future investigations may reveal therapeutic targets for possible intervention and ultimately the prophylaxis of PTOA development.

Ankle arthrodesis through minimally-invasive transfibular approach: a new surgical technique

PURPOSE

The purpose of our work was to demonstrate the surgical technique of ankle arthrodesis using the minimally-invasive transfibular (MITF) approach, which minimizes soft tissue damage and is advantageous for high-risk patients.

METHODS

In this prospective study, a total of 12 patients with end-stage varus ankle osteoarthritis, including high-risk individuals, underwent ankle arthrodesis using the MITF approach. The technique involves a unique osteotomy at the joint space level, minimizing soft tissue detachment from the fibula. The primary outcomes assessed included bony union, time to weight-bearing, correction of varus deformity, and functional outcomes measured by the American Orthopedic Foot and Ankle Society (AOFAS) hindfoot scale. However, the study's limitations encompass a small sample size and the absence of a control group.

RESULTS

At 6 months post-operation, all patients achieved bony union, with a mean time to union of 13.7 ± 5.2 weeks. The average time to initiate weight-bearing without additional support was 11.2 ± 3.8 weeks. Preoperative varus deformity (17.08 ± 8.36 degrees) and talar tilt (8.75 ± 4.33 degrees) were successfully corrected, with postoperative alignment within 0-5 degrees of valgus. Functional outcomes showed a significant improvement in AOFAS scores from 37.83 ± 7.79 points preoperatively to 77.42 ± 5.63 points one year after surgery (p = 0.002). Minor complications occurred in two patients, both effectively treated with local therapy and antibiotics.

CONCLUSIONS

The MITF approach for ankle arthrodesis demonstrates promising results in addressing end-stage varus ankle osteoarthritis, even in high-risk patients. However, the study's limitations highlight the need for a prospective comparative clinical trial with a larger sample size to ascertain the technique's effectiveness and safety definitively.

3D kinematics of tibiotalar motion in patients with mobile bearing and fixed bearing total ankle arthroplasty: In vivo videofluoroscopic feasibility study

BACKGROUND

As total ankle arthroplasty (TAA) is an increasingly common surgical intervention for patients with end-stage ankle arthritis, there is a need to better understand the dynamic performance of prosthetic implants during activities of daily living. Our purpose was to quantify and compare relative tibiotalar motion during gait in persons with a fixed-bearing (FB) and mobile-bearing (MB) total ankle arthroplasty. We hypothesized a FB prosthesis would have lower tibiotalar range of motion (ROM).

METHODS

Patients at least 12 months postoperative with either a FB (n=5) or MB (n=3) total ankle arthroplasty were tested. We used high-speed biplanar videoradiography to quantify tibiotalar kinematics during self-selected gait. Angular and linear ROM in three axes were compared between the groups.

RESULTS

ROM for dorsiflexion-plantarflexion, internal-external rotation, and inversion-eversion angles in FB subjects averaged 7.47±4.05°, 7.39±3.63°, and 4.51±2.13°, respectively. ROM in MB subjects averaged 6.74±2.04°, 6.28±4.51°, and 5.68±2.81°, respectively. Linear ROM along anteroposterior, mediolateral, and superior-inferior axes in FB subjects averaged 1.47±2.07 mm, 1.13±1.49 mm, and 0.28±0.30 mm, respectively. Linear ROM in MB subjects averaged 0.68±1.44 mm, 0.60±1.41 mm, and 0.20±0.13 mm, respectively. We found no significant difference between the two groups for any of these ROM parameters (p>0.05).

CONCLUSION

Total ankle arthroplasty using either FB or MB design appears to confer similar ankle motion during the gait cycle in this biplanar fluoroscopic model.

LEVEL OF EVIDENCE

Level IV, case series.

Trends in the use of ankle arthrodesis and total ankle replacements in Australia over the past 20 years

BACKGROUND

End stage ankle osteoarthritis (OA) is debilitating. Surgical management consists of either ankle arthrodesis (AA) or a total ankle replacement (TAR). The purpose of this study is to assess the trends in operative intervention for end stage ankle OA in an Australian population.

METHODS

This is a retrospective epidemiological study of 15,046 surgeries. Data were collected from publicly available national registries including the Australian Medicare Database and Australian Orthopaedic Association National Joint Replacement Registrar from 2001 to 2020.

RESULTS

There was a significant increase in all ankle surgeries performed across the period of interest. AA remained the more commonly performed procedure throughout the course of the study (11,946 cases, 79.4%) and was never surpassed by TAR (3100, 20.6%). The overall proportions demonstrated no significant changes from 2001 to 2020.

CONCLUSION

The incidence of ankle surgeries continues to increase with the ageing and increasingly comorbid population of Australia. Despite demonstrating no significant overall change in the ratio of TAR and AA in our study population and period, there are noticeable trends within the timeframe, with a recent surge favouring TAR in the last 5 years.

Effect of novel polyethylene insert configurations on bone-implant micromotion and contact stresses in total ankle replacement prostheses: a finite element analysis

Purpose

This study investigates the impact of elastic improvements to the artificial ankle joint insert on prosthesis biomechanics to reduce the risk of prosthesis loosening in TAR patients.

Methods

CT data of the right ankle was collected from one elderly female volunteer. An original TAR model (Model A) was developed from CT images and the INBONE II implant system. The development of the new inserts adopts an elastic improvement design approach, where different geometric configurations of flexible layers are inserted into the traditional insert. The structure can be divided into continuous flexible layers and intermittent flexible layers. The flexible layers aim to improve the elasticity of the component by absorbing and dispersing more kinetic energy. The newly designed inserts are used to replace the original insert in Model A, resulting in the development of Models B-D. A finite element model of gait analysis was based by gait parameters. Discrepancies in micromotion and contact behaviour were analysed during the gait cycle, along with interface fretting and articular surface stress at 50% of the gait cycle.

Results

In terms of micromotion, the improved elastic models showed reduced micromotion at the tibial-implant interfaces compared to the original model. The peak average micromotion decreased by 12.1%, 13.1%, and 14.5% in Models B, C, and D, respectively. The micromotion distribution also improved in the improved models, especially in Model D. Regarding contact areas, all models showed increased contact areas of articular surfaces with axial load, with Models B, C, and D increasing by 26.8%, 23.9%, and 24.4%, respectively. Contact stress on articular surfaces increased with axial load, reaching peak stress during the late stance phase. Models with continuous flexible layer designs exhibited lower stress levels. The insert and the talar prosthetic articular surfaces showed more uniform stress distribution in the improved models.

Conclusion

Improving the elasticity of the insert can enhance component flexibility, absorb impact forces, reduce micromotion, and improve contact behavior. The design scheme of continuous flexible layers is more advantageous in transmitting and dispersing stress, providing reference value for insert improvement.

Younger Patients Undergoing Total Ankle Arthroplasty Experience Higher Complication Rates and Worse Functional Outcomes

BACKGROUND

Although many patients with posttraumatic ankle arthritis are of a younger age, studies evaluating the impact of age on outcomes of primary total ankle arthroplasty (TAA) have revealed heterogenous results. The purpose of the present study was to determine the effect of age on complication rates and patient-reported outcomes after TAA.

METHODS

We retrospectively reviewed the records of 1,115 patients who had undergone primary TAA. The patients were divided into 3 age cohorts: <55 years (n = 196), 55 to 70 years (n = 657), and >70 years (n = 262). Demographic characteristics, intraoperative variables, postoperative complications, and patient-reported outcome measures were compared among groups with use of univariable analyses. Competing-risk regression analysis with adjustment for patient and implant characteristics was performed to assess the risk of implant failure by age group. The mean duration of follow-up was 5.6 years.

RESULTS

Compared with the patients who were 55 to 70 years of age and >70 years of age, those who were <55 years of age had the highest rates of any reoperation (19.9%, 11.7%, and 6.5% for the <55, 55 to 70, and >70-year age groups, respectively; p < 0.001), implant failure (5.6%, 2.9%, and 1.1% for the <55, 55 to 70, and >70-year age groups, respectively; p = 0.019), and polyethylene exchange (7.7%, 4.3%, and 2.3% for the <55, 55 to 70, and >70-year age groups, respectively; p = 0.021). Competing-risk regression revealed a decreased risk of implant failure for patients who were >70 of age compared with those who were <55 years of age (hazard ratio [HR], 0.21 [95% confidence interval (CI), 0.05 to 0.80]; p = 0.023) and for patients who were 55 to 70 years of age compared with those who were <55 years of age (HR, 0.35 [95% CI, 0.16 to 0.77]; p = 0.009). For all subscales of the Foot and Ankle Outcome Score (FAOS) measure except activities of daily living, patients who were <55 years of age reported the lowest (worst) mean preoperative and postoperative scores compared with those who were 55 to 70 years of age and >70 years of age (p ≤ 0.001). Patients who were <55 years of age had the highest mean numerical pain score at the time of the latest follow-up (23.6, 14.4, 12.9 for the <55, 55 to 70, and >70-year age groups, respectively; p < 0.001).

CONCLUSIONS

Studies involving large sample sizes with intermediate to long-term follow-up are critical to reveal age-related impacts on outcomes after TAA. In the present study, which we believe to be the largest single-institution series to date evaluating the effect of age on outcomes after TAA, younger patients had higher rates of complications and implant failure and fared worse on patient-reported outcome measures.

LEVEL OF EVIDENCE

Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Simultaneous hybrid closed-wedge supramalleolar osteotomy and ankle arthrodesis for post-traumatic varus ankle arthritis with periarticular deformity: A case report

The treatment of end-stage ankle arthritis associated with extra-articular tibial deformity, especially for ankles deformed by previous traumatic injuries and/or surgical treatment, is extremely challenging but rewarding. Only one previous report describes simultaneous tibial deformity correction and ankle arthrodesis for tibial malalignment and ipsilateral ankle arthritis. Here, we describe a unique case of post-traumatic ankle osteoarthritis concomitant with extra-articular varus deformity in a 77-year-old female. We have combined medial opening-wedge supramalleolar osteotomy (SMO) and lateral closed-wedge SMO in this case, which we termed 'hybrid' closed-wedge SMO, to overcome the limitations of traditional closed-wedge SMO. The patient was successfully treated with simultaneous hybrid closed-wedge SMO and ankle arthrodesis using a single lateral locking plate. To our knowledge, this is the first report describing the successful introduction of a hybrid closed-wedge osteotomy procedure in the distal tibia. Three years after surgery, the patient could walk without assistance and swim normally. The patient experienced no discomfort or pain in the operated ankle and was satisfied with the results. Radiographs confirmed that the pre-existing ankle joint line was parallel to the ground and almost invisible. The hind foot alignment was slightly valgus. No progression of the subtalar joint arthritis was detected. The simultaneous hybrid closed-wedge SMO and ankle arthrodesis was technically difficult but effective. This technique preserves leg length and subtalar joint motion. Additionally, a single lateral incision minimises the risk of impaired blood supply. The one-stage surgical treatment reduces the recovery time, duration of hospitalisation, and surgical costs. Rigid locking fixation with careful postoperative weight-bearing is required for uneventful bone healing.

Total Ankle Replacement Infections: A Systematic Review of the Literature

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

The Ankle Joint: Updates on Ankle Fusion Approaches and Fixation

Ankle fusion is a well-studied, classical procedure for conditions affecting the ankle joint, and has a long history with predictable results. Although there are many different approaches available, a few options are commonly used. The two main focuses of modern literature are on anterior plating versus traditional screw fixation, and on arthroscopic versus open techniques for fusion. This article discusses recent literature and then presents cases and techniques that are commonly used today. This includes arthroscopic ankle arthrodesis, traditional transfibular approach, anterior plating, and the indications and application of external fixation. Standard recovery and complications are discussed.

Midterm Results of AAA Ankle Arthroplasty

BACKGROUND

Outcome reports for Alpha Ankle Arthroplasty (AAA), a third-generation implant relying on a mobile bearing design for total ankle replacement, are sparse. This retrospective study evaluated the midterm survivorship, clinical, and radiologic outcomes after implantation of this implant.

METHODS

For 64 patients who received 65 Triple A ankle implants between 2009 and 2020, implant survival was calculated using the Kaplan-Meier curve. Clinical outcomes were evaluated by measuring the range of motion, stability, Western Ontario and McMaster Universities Osteoarthritis Questionnaire score (WOMAC), and American Orthopaedic Foot & Ankle Society ankle-hindfoot score (AOFAS). The average pain level and satisfaction with the postoperative result were rated on a numeric rating scale (0-10). Additionally, radiologic analysis was performed using anteroposterior and lateral radiographs and tibiotalar alignment was assessed.

RESULTS

The implant-survival rate was 61.5% at a mean follow-up of 8.2 years. Twenty-five patients (38.5%) required revision surgery (average time to revision, 3.1 years, 95% CI 2.1-4.1 years). For patients without revisions, the average range of motion in dorsiflexion and plantarflexion were 3.6 ± 4.2 degrees and 21.9 ± 7.8 degrees, respectively. The mean WOMAC and AOFAS scores were 44.7 ± 47.5 and 75.1 ± 14.0, respectively. The average pain and subjective satisfaction scores were 2.0 ± 1.7 and 8.5 ± 1.9, respectively. Mean alignment values did not differ significantly for patients who required revision surgery.

CONCLUSION

We found a high revision rate with use of the AAA. However, patients who did not require revision surgery had, on average, high satisfaction and good functional outcomes.

LEVEL OF EVIDENCE

Level IV, case series.

Republication of "Total Ankle Replacement Conversion to Tibiotalocalcaneal Arthrodesis With Bulk Femoral Head Allograft and Pseudoelastic Intramedullary Nail Providing Sustained Joint Compression"

Tibiotalocalcaneal (TTC) arthrodesis is commonly performed to salvage a failed total ankle replacement. These salvage procedures are complicated by significant bone loss from the ankle replacement and are associated with low patient satisfaction. Here, we describe 2 cases of patients who presented with a failed total ankle replacement and underwent arthrodesis using a bulk femoral head allograft and a novel pseudoelastic intramedullary nail. The intramedullary nail contains an internal pseudoelastic element that adapts to bone resorption and settling allowing for compression to be maintained at the arthrodesis sites throughout healing. In the first case, a 65-year-old woman with a failed total ankle replacement underwent TTC arthrodesis. The second case involved an obese 53-year-old woman who had previously undergone 2 total ankle replacement procedures that resulted in unsuccessful outcomes. In both cases, union was demonstrated on computed tomographic scan by 6 months. At 2 years postsurgery, both patients were satisfied with the procedure. These cases provide preliminary evidence that tibiotalocalcaneal arthrodesis with a pseudoelastic IM nail and structural allograft is an appropriate treatment for failed total ankle replacements. Level of Evidence: Level IV, therapeutic, case series.

Biomechanics and Tribology of Total Ankle Replacement

This article discusses the biomechanics and tribology of total ankle replacements considering the influence of implant design and generation on functional outcome, before discussing the interplay between biomechanics and tribology in the clinical success of total ankle replacement. It reflects on what we know and highlights areas for further research, as well as identifying factors to consider in clinical practice.

Computed Tomography Derived Patient-specific Instrumentation Total Ankle Arthroplasty Survivorship Outcomes

Computed tomography (CT) derived patient-specific total ankle arthroplasty (TAA) systems have been utilized for improved accuracy and reproducible implant alignment. The purpose of the present study was to report the overall implant survivorship as well as radiographic analysis of patients who underwent primary TAA utilizing CT-derived patient-specific instrumentation. A retrospective review of medical charts and radiographs were performed on patients who had undergone primary TAA at a single institution in the Midwest region from March 2013 to October 2020. Radiographic analysis included preoperative, initial postoperative, and final follow-up coronal and sagittal tibiotalar alignment as well as periprosthetic radiolucency. A total of 96 patients with a mean follow-up of 3 years (range, 0.3-7.3 years) were included. Implant survivorship was found to be 92% at median follow-up of 3 years. A total of 8 cases (8.3%) required revision/reoperation, with 6 (6.3%) of these reoperations directly related for failure of one of the metallic implant components. There was significant improvement in both coronal and sagittal tibiotalar alignment from preoperative to initial postoperative follow-up (p < .001). At latest postoperative follow-up, there were 88% of TAAs that remained in a neutral alignment following surgery. A total of 10 cases were found to have radiolucency at latest follow-up. In conclusion, the use of CT derived patient-specific TAA showed high implant survivorship with significant improvement of sagittal and coronal tibiotalar alignment. With better implant alignment and position, it potentially reduces the risk of early implant failure or implant loosening in long-term follow-up.

Incidence of ankle arthrodesis and total ankle replacement between 1997 and 2018: A nationwide registry study in Finland

BACKGROUND

Surgical treatment options for end-stage ankle osteoarthritis (OA) include ankle arthrodesis (AA) and total ankle replacement (TAR). We investigated the national incidence of AA and TAR and assessed trends in the surgical management of ankle OA in Finland between 1997 and 2018.

METHODS

The Finnish Care Register for Health Care was used to calculate the incidence of AA and TAR based on sex and different age groups.

RESULTS

The mean age (SD) of patients was similar, 57.8 (14.3) years for AA and 58.1 (14.0) for TAR. TAR showed a 3-fold increase from 0.3 per 100 000 person-years in 1997 to 0.9 per 100 000 person-years in 2018. The incidence of AA operations decreased during the study period from 4.4 per 100 000 person-years in 1997 to 3.8 per 100 000 person-years in 2018. TAR utilization increased notably at the expense of AA between 2001 and 2004.

CONCLUSION

TAR and AA are both widely used procedures in the treatment of ankle OA, with AA being the favored option for most patients. The incidence of TAR has remained constant for the past 10 years, indicating appropriate treatment indications and utilization.

Complications Following Total Ankle Arthroplasty Versus Ankle Arthrodesis for Primary Ankle Osteoarthritis

INTRODUCTION

There are minimal data comparing complications between ankle arthrodesis (AA) versus total ankle arthroplasty (TAR) for operative management of primary osteoarthritis (OA). This study aimed to compare outcomes following AA versus TAR for primary ankle OA using a large patient database.

METHODS

Patients who received AA or TAR for primary ankle OA from 2010 to 2019 were queried from PearlDiver. Rates of common joint complications were compared at 90 days, 1 year, and 2 years postoperatively using multivariable logistic regression.

RESULTS

A total of 1136 (67%) patients received AA and 584 (33%) patients underwent TAR. Patients that received AA exhibited significantly higher rates of at least one common joint complication at 90 days (19.3% vs 12.6%; odds ratio [OR] 1.69), 1 year (25.6% vs 15.0%; OR 2.00), and 2 years (26.9% vs 16.2%; OR 1.91) postoperatively. This included higher rates of adjacent fusion or osteotomy procedures, periprosthetic fractures, and hardware removal at each postoperative follow-up (all P < .05). Rates of prosthetic joint infection were comparable at 2 years postoperatively (4.3% vs 4.2%; OR 0.91).

CONCLUSION

The AA cohort exhibited higher rates of postoperative joint complications in the short and medium-term, namely, subsequent fusions or osteotomies, periprosthetic fractures, and hardware removal.

LEVELS OF EVIDENCE

Level III.

Reoperation Rates Following Total Ankle Arthroplasty Versus Ankle Arthrodesis for Posttraumatic Indications

AIMS

This studied aimed to compare rates of reoperation for patients who received primary ankle arthrodesis (AA) versus total ankle replacement (TAR) for posttraumatic indications between 2010 and 2016 Q2 using a nationwide claims database.

METHODS

A retrospective cohort study analyzing patients who received primary AA or TAR for posttraumatic indications was performed using PearlDiver. Reoperations assessed included prosthetic joint infection (PJI), hardware removal, adjacent joint fusion, and local open reduction internal fixation (ORIF). Multivariable logistic regression was used to compare rates of reoperations at 1 and 2 years postdischarge.

RESULTS

A total of 862 (74%) patients received AA and 318 (26%) patients underwent TAR for a posttraumatic indication. At 1 year, 305 (35.4%) AA patients had at least 1 reoperation compared with 55 (17.3%) TAR patients (OR 2.32; 95% CI, 1.68-3.26). At 2 years, 364 (42.2%) AA patients and 66 (20.8%) TAR patients had at least 1 reoperation (OR 2.51; 95% CI, 1.84-3.45). ORIF, hardware removal, and adjacent joint fusions were more likely for AA patients at both time intervals (all Ps < .05).

CONCLUSION

Patients who received primary AA for posttraumatic indications exhibited higher rates of major reoperations in the short to medium term compared with patients who underwent TAR.

LEVELS OF EVIDENCE

Level III: Retrospective cohort study.

Complications following total ankle arthroplasty: A systematic literature review and meta-analysis

BACKGROUND

Total ankle arthroplasty (TAA) is increasingly used as a treatment for end-stage ankle arthropathy. However, TAA may be more sensitive to complications, failure and subsequent re-operations compared to ankle arthrodesis. The aim of this systematic review and meta-analysis is to generate an overview of complications of TAA surgery.

METHODS

PubMed, EMBASE and the Cochrane library were searched between 2000 and 2020 to identify all papers reporting on complications in TAA surgery. Meta-analysis was conducted based on type of complication in TAA surgery. Pooled estimates of complications were calculated using a random effects model. Risk of bias and quality was assessed using the Cochrane risk of bias and ROBINS-I tools. The confidence in estimates was rated and described according to the recommendations of the GRADE working group.

RESULTS

One hundred twenty-seven studies were included in this systematic review. All combined, they reported on 16.964 TAAs with an average follow-up of 47.99 ± 29.18 months. Complications with highest reported pooled incidence were intra-operative fracture 0.06 (95 %CI 0.04-0.08) (GRADE Very low) and impingement 0.06 (95 %CI 0.04-0.08) (GRADE low) respectively.

CONCLUSION

Reported complication incidence of TAA surgery is still high and remains a significant clinical problem that can be severely hampering long-term clinical survival of the prosthesis. The results of this systematic review and meta-analysis can help guide surgeons in informing their patient about complication risks. Implementation of more stringent patient selection criteria might contribute to diminishing TAA complication rates.

Consumer Interest in Total Ankle Replacements Over the Last 10 Years: A Google Trends™ Analysis From 2009 to 2019

With an aging population, the incidence of osteoarthritis (OA) continues to grow. After exhausting conservative therapy for many forms of OA, patients regularly opt for surgical intervention in the form of total joint replacement surgery. One form, total ankle replacement, has continued to gain favorability in the medical community. Improved implant design and surgical technique have enabled success rates of total ankle replacements to approach those of the hip and knee. As a new and improving therapy to address end-stage ankle OA, knowledge of patient-interest has yet to be determined. We used search inquiry data for the keywords "ankle arthritis" "ankle replacement" and "ankle fusion" available from Google Trends™ to identify trends in patient and geographic interest from 2009 to 2019. Search inquiries significantly increased for all keywords over time (p < .001). Trend analysis over this 10-year period revealed a strong correlation for ankle arthritis (0.88) and ankle replacement (0.76). Moreover, the correlation between "ankle arthritis" and "ankle replacement" was strong (0.83) during this period. The geographic distribution of these search terms showed the greatest increase in interest for the keywords "ankle arthritis" "ankle replacement" and "ankle fusion" in Arizona, New York, and Virginia respectively. Results of this study illustrate a similar increasing patient interest in ankle arthritis and ankle replacements. This data can be used effectively identify, educate, and treat populations interested in ankle replacements. To the best of our knowledge, this is the first study to utilize Google Trends™ to analyze patient interest in foot and ankle surgery.

Utilization Trends of Total Ankle Arthroplasty and Ankle Fusion for Tibiotalar Osteoarthritis: A Nationwide Analysis of the United States Population

Introduction: Studies evaluating utilization and trends of total ankle arthroplasty (TAA) and ankle fusion (AF) are sparse. The purpose of this study was to use a nationwide administrative claims database to compare baseline demographics between TAA and ankle arthrodesis and to determine whether patients who had a TAA have increased rates of: (1) utilization, (2) in-hospital length of stay (LOS), and (3) costs of care. Methods: PearlDiver, a nationwide claims database was queried from 2005 to December 2013 for all patients who underwent primary TAA or AF for the treatment of osteoarthritis of the ankle and foot. Baseline demographics of age, sex, geographic distribution, and the prevalence of comorbidities comprising the Elixhauser comorbidity index (ECI) were compared between patients who had TAA and AF. Linear regression was used to compare differences in utilization and in-hospital LOS between the 2 cohorts during the study interval. Annual charges and reimbursement rates for TAA were assessed during the study period. A P value less than .05 was considered to be statistically significant. Results: A total of 21 433 patients undergoing primary TAA (n = 7126) and AF (n = 14 307) were included. Patients undergoing TAA had significantly greater ECI driven by arrythmias, congestive heart failure, diabetes mellitus, electrolyte/fluid disorders, iron deficiency anemia than patients undergoing AF (P < .001). From 2005 to 2013, TAA utilization increased from 21.5% to 49.4% of procedures (P < .0001). There was reduced in-hospital LOS over the time interval for patients with TAA compared with AF (2.15 days vs. 3.11 days, P < .0001). Total ankle arthroplasty reimbursements remained stable while charges per patient increased significantly from $40 203.48 in 2005 to doubling by the end of 2013 to $86 208.59 (P < .0001). Conclusion: This study demonstrated increased use of TAA compared to AF showing decreased in-hospital LOS and increased cost of care with stagnant reimbursement rates.Level of Evidence: Level III.

Preliminary Report of a Hybrid Total Ankle Arthroplasty Combining a Stemmed Intramedullary Tibial Component With Chamfer-Cut Talar Dome

Total ankle arthroplasty (TAA) is a viable treatment for end-stage ankle arthritis. In our experience, a stemmed intramedullary tibial component combined with a chamfer-cut talar component provides the most stable construct for TAA. We present our technique for placement of this hybrid prosthesis utilizing the INBONE tibial component in combination with the INFINITY talar component. This technique differs from the standard protocol by minimizing use of both patient-specific and standard intraoperative guides. The primary aim of this study is to report our preliminary outcomes with our novel technique. Secondarily, we aim to demonstrate that placement of this hybrid prosthesis is radiographically reproducible and accurate. The first 10 patients undergoing this technique with at least 1 year of follow-up were retrospectively reviewed. Average visual analog pain scale decreased from 7.4 preoperatively to 0.5 at 1 year postoperatively. The average time to weightbearing was 6.4 weeks. Complications were minimal, and no implant-related complications were encountered. First weightbearing ankle radiographs postoperatively were evaluated by 3 reviewers to determine accuracy of the tibial intramedullary stem in relation to the anatomical axis of the tibia. We found that the deviation of the tibial implant from the anatomic axis was on average 0.9°± 0.5° in the coronal plane, and 2.2°± 2.7° in the sagittal plane. Inter-rater reliability was 83%. We conclude that this hybrid technique utilizing a stemmed intramedullary tibial component in combination with a chamfer-cut talar component for TAA is reproducible, accurate, and safe.

Does Concurrent Distal Tibiofibular Joint Arthrodesis Affect the Nonunion and Complication Rates of Tibiotalar Arthrodesis?

Tibiotalar arthrodesis successfully treats ankle arthritis but carries risk of nonunion. It is unclear whether concurrent distal tibiofibular arthrodesis affects tibiotalar nonunion rate. The purpose of this study is to compare tibiotalar nonunion and complication rates in patients with versus without a distal tibiofibular arthrodesis. This is a retrospective review of 516 consecutive ankle arthrodesis performed between March 2002 and May 2016. A total of 319 ankles (312 patients) underwent primary, open tibiotalar arthrodesis (227 with distal tibiofibular arthrodesis, 92 without). Primary outcome measure was nonunion rate. Secondary outcome measures were time to tibiotalar union, rate of development of post-operative deep vein thrombosis (DVT)/pulmonary embolism (PE), rate of deep wound complications, and rate of return to operating room (OR). No differences in nonunion rates were observed in both cohorts of patients with versus without distal tibiofibular arthrodesis: 17/227 (7.5%) versus 11/92 (12%) (p = 0.2), respectively, odds ratio was 0.74, 95% CI: 0.29~2.08 (p = 0.55). There was no difference in deep wound complications (5.3% versus 10.9%, p = 0.42), time to union (3.7 months versus 4.1 months, p = 0.72), or rate of development of DVT/PE (5.2% versus 2.2%, p = 0.18) between patients with and without distal tibiofibular arthrodesis, respectively. This is the first study directly comparing nonunion and complication rates in primary, open ankle arthrodesis with and without distal tibiofibular arthrodesis. Inclusion of the distal fibular joint with the tibiotalar fusion was not associated with a change in tibiotalar nonunion rate, time to union, wound complications, or postoperative DVT/PE.

Comparison of patient demographics, utilization trends, and costs of total ankle arthroplasty and ankle fusion in the United States from 2010 to 2019

INTRODUCTION

Contemporary studies evaluating utilization and trends of total ankle arthroplasty (TAA) and ankle fusion (AF) for tibiotalar osteoarthritis are sparse. Therefore, the purpose of this study was to utilize a nationwide administrative claims database from 2010 to 2019 to compare: (1) baseline demographics; (2) utilization, (3) in-hospital length of stay (LOS), and (4) costs of care.

METHODS

Using the PearlDiver database, a retrospective query from January 1st, 2010 to December 31st, 2019 was performed for all patients who underwent TAA and AF for tibiotalar osteoarthritis. Baseline demographics, comorbidities, and geographic utilization were compared using Pearson Chi-square analyses. Linear regression was used to compare differences in procedure utilization and in-hospital LOS during the study interval. Reimbursements between the two cohorts during the study interval were compared. A p value less than 0.05 was statistically significant.

RESULTS

In total, 14,248 patients underwent primary TAA (n = 5544) or AF (n = 8704). Patients undergoing AF were generally younger (< 60) with greater comorbidity burden driven by hypertension, diabetes mellitus, obesity, and tobacco use compared to TAA patients (p < 0.0001). Over the study interval, TAA utilization remained constant (912 vs 909 procedures; p = 0.807), whereas AF utilization decreased by 42.5% (1737 vs 998 procedures; p = 0.0001). Mean in-hospital LOS for patients undergoing TAA decreased (2.5 days vs. 2.0 days, p = 0.0004), while AF LOS increased (2.6 days vs. 3.5 days, p = 0.0003). Reimbursements for both procedures significantly declined over the study interval (TAA: $4559-$2156, AF: $4729-$1721; p < 0.013).

CONCLUSION

TAA utilization remained constant, while AF utilization declined by 42.5% from 2010 to 2019. There was divergence in the LOS for TAA versus AF patients. Both procedures significantly declined by over 50% in reimbursements over the study interval.

Nationwide Analysis of Total Ankle Replacement and Ankle Arthrodesis in Medicare Patients: Trends, Complications, and Cost

BACKGROUND

Surgical management of end-stage ankle arthritis consists of either ankle arthrodesis (AA) or total ankle replacement (TAR). The purpose of this study was to evaluate utilization trends in TAR and AA and compare cost and complications.

METHODS

Medicare patients with the diagnosis of ankle arthritis were reviewed. Patients undergoing surgical intervention were split into AA and TAR groups, which were evaluated for trends as well as postoperative complications, revision rates, and procedure cost.

RESULTS

A total of 673 789 patients were identified with ankle arthritis. A total of 19 120 patients underwent AA and 9059 underwent TAR. While rates of AA remained relatively constant, even decreasing, with 2080 performed in 2005 and 1823 performed in 2014, TAR rates nearly quadrupled. Average cost associated with TAR was $12559.12 compared with $6962.99 for AA (P < .001). Overall complication rates were 24.9% in the AA group with a 16.5% revision rate compared with 15.1% and 11.0%, respectively, in the TAR group (P < .001). Patients younger than 65 years had both higher complication and revision rates.

DISCUSSION

TAR has become an increasingly popular option for the management of end-stage ankle arthritis. In our study, TAR demonstrated both lower revision and complication rates than AA. However, TAR represents a more expensive treatment option.

LEVELS OF EVIDENCE

Level III: Retrospective comparative study.

Survival of primary ankle replacements: data from global joint registries

BACKGROUND

Ankle arthroplasty, commonly known as ankle replacement, is a surgical procedure for treating end-stage ankle osteoarthritis. Whilst evidence shows good clinical results after surgery, little is known of the long-term survival of ankle replacements and the need for ankle revision. Using more recent implant data and long-term data, there is now opportunity to examine at a population-level the survival rate for ankle implants, to examine between-country differences in ankle revision surgery, and to compare temporal trends in revision rates between countries.

METHODS

Four national joint registries from Australia, New Zealand, Norway and Sweden provided the necessary data on revision outcome following primary ankle replacement, for various periods of observation - the earliest starting in 1993 up to the end of 2019. Data were either acquired from published, online annual reports or were provided from direct contact with the joint registries. The key information extracted were Kaplan-Meier estimates to plot survival probability curves following primary ankle replacement.

RESULTS

The survival rates varied between countries. At 2 years, across all registries, survival rates all exceeded 0.9 (range 0.91 to 0.97). The variation widened at 5 years (range 0.80 to 0.91), at 10 years (range 0.66 to 0.84) and further at 15-years follow-up (0.56 to 0.78). At each time point, implant survival was greater in Australia and New Zealand with lower rates in Sweden and Norway.

CONCLUSIONS

We observed variation in primary ankle replacement survival rates across these national registries, although even after 5 years, these population derived data show an 80% revision free survival. These data raise a number of hypotheses concerning the reasons for between-country differences in revision-free survival which will require access to primary data for analysis.

Survivorship of 4,748 Contemporary Total Ankle Replacements from the French Discharge Records Database

BACKGROUND

Studies of survivorship of primary total ankle replacements (TARs) beyond 5 years have shown varying results among early and modern designs. National cohorts give valuable insights about TAR outcomes, revision risk factors, and specific designs. The purpose of this study was to investigate implant survivorship and risk factors for revision of contemporary TARs using our national database.

METHODS

This observational study included patients identified in the national PMSI (Programme médicalisé des systèmes d'information) database as having undergone TAR from 2010 to 2019. Demographics, discharge data, concomitant procedures, and type of implant were extracted. Kaplan-Meier estimations were performed to determine time to revision using metal component revision for implant failure and revision for deep infection as end points. Weighted Cox models were used for risk factor analysis, including risks of early revision (within the first 2 years). The adjusted hazard ratios (HRadj) were reported with 95% confidence intervals.

RESULTS

A cohort of 4,748 patients was extracted. The mean age at surgery was 63 years; 43% of the patients were female. The mean follow-up was 5 years (range, 1 to 10 years). Revisions were noted in 817 cases (17%), including 734 with metal component revision and 83 with revision due to deep infection. The 1-year, 2-year, 5-year, and 10-year survivorship free of metal component revision was 95%, 90%, 84%, and 78%, respectively. Younger age, implants derived from second-generation designs, and an institutional volume of ≤10 TARs per year were found to be independent predictors of revision for any cause. In addition to the above factors (except for implant generation), male sex and concomitant osteotomies and/or fusion were found to be significant predictors for any early revision.

CONCLUSIONS

The 10-year survivorship free of metal component revision after TAR was 78%, which was consistent with other national registries. Revisions were associated with young age, associated arthritis or deformities requiring concomitant fusion or osteotomy, and implants derived from second-generation designs. Institutions where >10 procedures were performed per year were associated with better TAR survivorship.

LEVEL OF EVIDENCE

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

Autologous osteophyte grafting for ankle arthrodesis

Purpose: Various graft sources had been identified to facilitate gap-filling in ankle arthrodesis procedures with related articular defects. This was a preliminary study with the aim of analyzing the efficacy and feasibility of using autologous osteophyte as a grafting source. Methods: Retrospective evaluation of ten patients having ankle arthrodesis procedure using identical anterior approach and plate fixation technique was conducted. Basic anthropometric measurements and underlying disease were recorded. Functional outcome and fusion rate were assessed at a 12-month post-surgery follow-up visit. Results: The underlying diseases include primary osteoarthritis (OA), post-traumatic OA, rheumatoid arthritis, and Charcot arthropathy. The patient’s age mean was 56.6 years (range 36–71 years), and BMI varied from 17.9 kg/m² to 29.3 kg/m². Nearly all patients had improved functional outcomes as described by foot and ankle ability measure (FAAM) score and fusion rate as described by modified radiographic union score for tibia (RUST). One patient had failed surgery due to implant failure with diminished protective foot sensory. Conclusion: Osteophytes from the distal tibia and talar neck were a viable source of bone graft, especially for ankle arthrodesis using anterior approach among various ages and BMI, in which the surgeons would not need additional incision for graft harvesting.

Open Ankle Arthrodesis for Deformity Correction

Open ankle arthrodesis remains a reliable solution for ankle arthritis, especially in the setting of deformity. Careful preoperative evaluation needs to be performed, both clinically and radiographically. The specific deformity present helps determine the approach used and the fixation choices. Deformity is most commonly seen intraarticularly, though deformity can also be present anywhere along the lower extremity, including compensatory deformity in the foot. Multiple different techniques can be used to address both the deformity and achieve a successful ankle arthrodesis. Patient outcomes reported in the literature are generally good, with high union rates and improved functional outcomes.

The 15 year ankle arthroplasty experience in a university hospital

INTRODUCTION

The study aim was to review the experience of ankle replacement surgery in a university teaching hospital.

METHODS

A retrospective review of primary ankle replacements performed between 2005 and 2019 was undertaken. Implant survival and reasons for revision surgery were assessed, along with patient reported outcomes and complications.

RESULTS

There were 157 ankle replacements implanted in 140 patients with a mean follow up 7.5 years (range 1.0-14.5). There were 108 Mobility™, 19 Zenith™ and 30 Infinity™ ankle replacements with an overall revision rate of 9.6% at a mean 4.0 years (range 0.1-11.0). Overall survivorship analysis for 5, 10 and 15 years was respectively 92.4%, 89.3% and 86.6%.

DISCUSSION

The revision rate was comparable to international registers and aseptic loosening was the commonest reason for revision. This study, in a teaching university hospital with an average of 10 primary ankle replacements each year, highlighted ankle arthroplasty provides good functional outcomes and medium term implant survivorship. This supports the use of ankle arthroplasty within foot and ankle specialist centres achieving appropriate outcomes.

The Safety Profile of Same-Day Outpatient Total Ankle Arthroplasty

There has been significant change in the health care policy in the United States in recent years with an increasing focus on health care costs and patient satisfaction. One strategy of cost containment is to transition outpatient surgery away from high cost hospital environments. Total ankle arthroplasty has begun the evolution to outpatient settings; however, there is limited published literature on the results of outpatient total ankle arthroplasty (TAA). The purpose of the present study was to review the safety profile of same day outpatient TAA at an ambulatory surgery center. A review of consecutive patients who underwent same day outpatient TAA for end-stage ankle arthritis with a minimum of 12 months' follow-up was performed. The primary outcomes assessed were the incidence of perioperative adverse medical events, hospital admissions related to the procedure, and postoperative complications (minor and major). Univariate analyses were performed. Fifty-one patients who underwent same-day TAA between June 2016 and July 2018 were included; mean follow-up was 20.7 months (± 7.6). The mean age at time of surgery was 56.5 years (± 7.2), with a mean body mass index of 30.4 (± 5.3). Overall, there were no perioperative adverse medical events or hospital admissions related to the procedure. Five minor complications (9.8%) and 7 major (13.7%) were recorded. Of the major complications, only 1 required TAA revision. Implant survivorship during the most recent follow-up was 98%. The present study suggests that TAA can be performed safely in an outpatient ambulatory setting. Additional comparative studies with larger TAA cohorts and patient reported outcomes are warranted.

Primary total ankle replacement surgery is a cost-effective intervention

AIMS

The primary aim was to assess the cost-effectiveness of primary total ankle replacements (PTAR) in the UK. Secondary aim was to identify predictors associated with increased cost-effectiveness of PTAR.

METHODS

Pre-operative and six-month post-operative data was obtained over a 90-month period across the two centres receiving adult referrals in the UK. The EuroQol general health questionnaire (EQ-5D-3L) measured health-related Quality of Life (HRQoL) and the Manchester-Oxford Foot Questionnaire (MOXFQ) measured joint function. Predictors, tested for significance with QALYs gained, were pre-operative scores and demographic data including age, gender, BMI and socioeconomic status. A cost per QALY of less than £20,000 was defined as cost effective.

RESULTS

The 51-patient cohort [mean age 67.70 (SD 8.91), 58.8% male] had 47.7% classed as obese or higher. Cost per QALY gained was £1669, rising to £4466 when annual (3.5%) reduction in health gains and revision rates and discounting were included. Lower pre-operative EQ-5D-3L index correlated significantly with increased QALYs gained (p < 0.01), all other predictors were not significantly (p > 0.05) associated with QALYs gained.

CONCLUSIONS

PTAR is a cost-effective intervention for treating end-stage ankle arthritis. Pre-operative EQ-5D-3L was associated with QALYs gained. A pre-operative EQ-5D-3L score of 0.57 or more was not cost effective to operate on.

Living With Both a Total Ankle Replacement and an Ankle Fusion: A Qualitative Study From the Patients' Perspective

BACKGROUND

Total ankle replacement (TAR) and ankle fusion are effective treatments for end-stage ankle arthritis. Comparative studies elucidate differences in treatment outcomes; however, the literature lacks evidence demonstrating what outcomes are important to patients. The purpose of this study was to investigate patients' experiences of living with both a TAR and ankle fusion.

METHODS

This research study used qualitative description. Individuals were selected from a cohort of patients with TAR and/or ankle fusion (n = 1254). Eligible patients were English speaking with a TAR and contralateral ankle fusion, and a minimum of 1 year since their most recent ankle reconstruction. Surgeries were performed by a single experienced surgeon, and semistructured interviews were conducted by a single researcher in a private hospital setting or by telephone. Ankle Osteoarthritis Scale (AOS) scores, radiographs, and ancillary surgical procedures were collected to characterize patients. Themes were derived through qualitative data analysis.

RESULTS

Ten adults (8 men, 2 women), ages 59 to 90 years, were included. Average AOS pain and disability scores were similar for both surgeries for most patients. Participants discussed perceptions of each reconstructed ankle. Ankle fusions were considered stable and strong, but also stiff and compromising balance. TARs were considered flexible and more like a "normal ankle," though patients expressed concerns about their TAR "turning" on uneven ground. Individuals applied this knowledge to facilitate movement, particularly during a first step and transitioning between positions. They described the need for careful foot placement and attention to the environment to avoid potential challenges.

CONCLUSION

This study provides insight into the experiences of individuals living with a TAR and ankle fusion. In this unusual but limited group of patients, we found that each ankle reconstruction was generally perceived to have different characteristics, advantages, and disadvantages. Most participants articulated a preference for their TAR. These findings can help clinicians better counsel patients on expectations after TAR and ankle fusion, and improve patient-reported outcome measures by better capturing meaningful outcomes for patients.

LEVEL OF EVIDENCE

Level IV, case series.

Establishing a New Patient-Specific Implantation Technique for Total Ankle Replacement: An In Vitro Study

BACKGROUND

Revision rates after total ankle replacements (TARs) are higher compared with other total joint replacements. The present study aimed to establish a new patient-specific implantation (PSI) technique for TAR.

MATERIAL AND METHODS

A total of 10 complete Caucasian cadaver legs had whole leg computed tomography scans. The individual geometrical ankle joint axis was determined, and based on this axis, the position of the prosthesis was planned. We assessed prosthesis placement, guiding block position, and preoperative and postoperative ankle rotational axes.

RESULTS

The guiding block position interobserver reliability was 0.37 mm 0.45 (mean ± SD) for the tibial guiding block. The value for the first talar guiding block was 1.72 ± 1.3 mm and for the second talar guiding block, 0.61 ± 0.39 mm. The tibial slope as well as the frontal angles of the anatomical tibial axis compared to the tibial and talar articular surfaces showed no statistically relevant differences with numbers available. The deviation of the assessed preoperative joint axis to the postoperative joint axis was 14.6° ± 7.8.

CONCLUSION

The present study describes the results of an establishing process of a new PSI technique for TAR. The reliability of guiding block positioning and, thereby, prosthesis placement is sufficient.

LEVEL OF EVIDENCE

Biomechanical study.

Outcome Reporting in Total Ankle Arthroplasty: A Systematic Review

Total ankle arthroplasty is an increasingly utilized treatment for ankle arthritis due to decreasing failure rates and improved outcomes. However, the literature on this procedure remains heterogeneous with large variability in outcome reporting methods. PRISMA guidelines were used to systematically review outcome reporting measures used in prospective studies and randomized control trials on total ankle arthroplasty published in 15 high-impact journals between Jan 1, 2009-May 1, 2020. A total of 43 studies were included and outcome measures were grouped into seven categories: pain, subjective function, patient satisfaction, complications, objective function, implant survivorship, and imaging. The most common topic of study was implant design followed by differences in outcomes when comparing total ankle arthroplasty and arthrodesis. The most commonly reported outcome measure was post-surgical complications. No study reported on all seven categories, while 22 (51.2%) studies reported on four or more. Subjective measures had significant variability with fifteen different Patient Reported Outcome Measures used across the studies. While the included studies were quite comprehensive, there was little consistency in reporting outcomes after total ankle arthroplasty. With improving outcomes and techniques in total ankle arthroplasty, and thus an expected increase in utilization and number of published studies, efforts should be made to use commonly employed outcome reporting methods to facilitate comparison of results across studies.

Total Ankle Arthroplasty Survivorship: A Meta-analysis

The gold standard for management of end-stage ankle arthritis was previously ankle arthrodesis; however, improvements in total ankle replacements are making this a more viable treatment option. The primary aim of this meta-analysis was to evaluate the survivorship of total ankle replacement implants currently in use. An extensive search strategy initially captured 20,842 citations that were evaluated for relevance. Abstract screening produced 97 articles to be read in entirety, of which 10 articles studying 1963 implants met all prospective inclusion criteria for analysis. Overall survivorship of all implants was 93.0% (95% confidence interval, 85.2-96.9) using a random effect model. There was significant heterogeneity between the studies (Q = 131.504). Meta-regression identified an inverse relationship between survivorship and study follow-up duration (p < .0001). Furthermore, age (p = .36) and implant type (fixed-bearing [95.6%, 95% confidence interval, 85.9-98.7] versus mobile-bearing ]89.4%, 95% confidence interval, 79.6%-94.8%]) did not have a statistically significant impact on survivorship, p = .213. However, patients with higher preoperative functional scores had improved survivorship (p = .001). Complications were inconsistently reported with varied definitions. In order of reported frequency, complications were classified into technical error (28.15%), subsidence (16.89%), implant failure (13.28%), aseptic loosening (6.3%), intraoperative fracture (5.67%), wound problems (4.3%), deep infection (1%), and postoperative fracture (0.0001%). Overall study quality was low, with only 10% being prospective and 90% from nonregistry data. The results from this meta-analysis revealed a promising overall survivorship of current implants in use for total ankle replacement; however higher quality studies with standardized outcomes measures are needed.

Effect of Gender Differences on Patient-Reported Outcomes and Complications in Total Ankle Replacement

BACKGROUND

The purpose of this study was to evaluate gender differences in patient outcomes and complications following total ankle replacement (TAR).

METHODS

Consecutive patients who underwent primary TAR from July 2007 through May 2016 were prospectively followed and retrospectively reviewed. Demographic, operative, patient-reported outcomes (PROs), and complication data were collected and analyzed. PROs included the visual analog scale (VAS), 36-Item Short-Form Health Survey (SF-36), American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot scale, and Short Musculoskeletal Function Assessment (SMFA). A total of 475 patients were evaluated, including 248 males (52.2%) and 227 females (47.8%) with an average of 56.8 months follow-up.

RESULTS

Women were more likely to have inflammatory arthritis (13.7% vs 2.8%; P < .01) and significantly worse preoperative SF-36 total, SF-36 mental health component, AOFAS total, AOFAS pain, SMFA function, and SMFA bother scores (all P < .05). Both genders demonstrated significant improvement in PROs at 1, 2, and 5 years. The magnitude of improvement was similar between genders for all PROs (all P < .05) with the exception of SF-36 physical function, which was greater in men. Females underwent more nonrevision reoperations (32.2% vs 22.6%; P = .0191), but there was no significant difference in failure rates (male 7.3% vs female 3.5%; P = .07). The reoperation and failure rates at 2 years postoperation were 10.1% and 1.6% for men and 18.5% and 0.9% for women, respectively.

CONCLUSION

Women undergoing TAR were more likely to have worse preoperative PROs and higher rates of nonrevision reoperations, which remains true when controlling for their increased incidence of inflammatory arthritis. However, women reported similar improvements in PROs and had similar prosthetic survival rates as men. Increased understanding of these disparities, combined with gender-based interventions, may further advance patient outcomes.

LEVEL OF EVIDENCE

Level III, therapeutic, retrospective comparative series.

Long-term Functional Results of Total Ankle Arthroplasty in Stiff Ankles

BACKGROUND

Total ankle arthroplasty (TAA) is advocated over ankle arthrodesis to preserve ankle motion (ROM). Clinical and gait analysis studies have shown significant improvement after TAA. The role and outcomes of TAA in stiff ankles, which have little motion to be preserved, has been the subject of limited investigation. This investigation evaluated the mid- to long-term functional outcomes of TAA in stiff ankles.

METHODS

A retrospective study of prospectively collected functional gait data in 33 TAA patients at a mean of 7.6 (5-13) years postoperatively used 1-way analysis of variance and multivariate regression analysis to compare among preoperative and postoperative demographic data (age, gender, body mass index, years postsurgery, and diagnosis) and gait parameters according to quartiles of preoperative sagittal ROM.

RESULTS

The stiffest ankles had a mean ROM of 7.8 degrees, compared to 14.3 degrees for the middle 2 quartiles, and 21.0 degrees for the most flexible ankles. Patients in the lowest quartile (Q1) also had statistically significantly lower step length, speed, max plantarflexion, and power preoperatively. Postoperatively, they increased step length, speed, max plantarflexion, and ankle power to levels comparable to patients with more flexible ankles preoperatively (Q2, Q3, and Q4). They had the greatest absolute and relative increases in these parameters of any group, but the final total ROM was still statistically significantly the lowest.

CONCLUSION

Preoperative ROM was predictive of overall postoperative gait function at an average of 7.6 (range 5-13) years. Although greater preoperative sagittal ROM predicted greater postoperative ROM, the stiffest ankles showed the greatest percentage increase in ROM. Patients with the stiffest ankles had the greatest absolute and relative improvements in objective function after TAA, as measured by multiple gait parameters. At intermediate- to long-term follow-up, patients with stiff ankles maintained significant functional improvements after TAA.

LEVEL OF EVIDENCE

Level III, comparative study.

Total Ankle Arthroplasty and Ankle Arthrodesis Use: An American Board of Orthopaedic Surgery Part II Database Study

Total ankle arthroplasty (TAA) use has increased during the past 20 years, whereas ankle arthrodesis (AAD) use has remained constant. The purpose of this study was to examine trends in TAA and AAD use in American Board of Orthopedic Surgery Part II candidates while considering the influence of fellowship training status on treatment of end-stage ankle arthritis. The American Board of Orthopedic Surgery Part II database was queried to identify all candidates who performed ≥1 TAA or AAD from examination years 2009 through 2018. Candidates were categorized by examination year and by self-reported fellowship training status. Descriptive statistical methods were used to report procedure volumes. Trends in use of TAA and AAD were examined by using log-modified regression analyses. From 2009through 2018, there was no significant change in TAA or AAD use among all candidates (p = .92, p = .20). Candidates reporting a foot and ankle fellowship trended toward increased use of TAA relative to AAD compared with non-foot and ankle fellowship candidates, but this failed to reach statistical significance (p = .06). The use of arthroscopic AAD increased over time (p < .01) among all candidates. TAA and AAD use did not change over the study period. Volume of TAA and AAD performed by early-career surgeons remains low. The findings in this study should serve as an important reference for orthopedic trainees, early-career surgeons, and orthopedic educators interested in optimizing training curriculum for surgical management of end-stage ankle arthritis.

A Survey for End-Stage Ankle Arthritis Treatment: Ankle Arthrodesis Versus Ankle Arthroplasty

With promising technological advances, ankle arthroplasty has become an alternative to arthrodesis, traditionally the gold standard, for treating end-stage ankle arthritis. We collected knowledge and perceptions on both procedures to determine the need for a patient decision aid for these patients by administering a cross-sectional survey to 103 orthopaedic surgeons. Respondents were predominantly male and 41 to 50 years old. Half of those who stated that they do not perform arthroplasty said this was because they do not have adequate training. Additionally, certain variables were associated with the surgeon's choice of intervention: patient gender, age, body mass index, postoperative activity level, employment type, perceived risk of infection, neurovascular injury or wound complication, risk of developing or pre-existing adjacent arthritis, deformity, malalignment, bone loss or abnormal bone quality, number of prior ankle operations, cause of arthritis, and desire for motion preservation. The majority agreed that they always incorporate patient preferences into their decisions and that a decision aid would be beneficial. This survey revealed that several patient characteristics are influential in the surgeon's preference for either arthroplasty or arthrodesis for end-stage ankle arthritis. Because the majority of surgeons incorporate patient preferences in their decisions and report that a decision aid would be beneficial for informed decision-making in this clinical scenario, this survey identified an unmet need supporting the development of such a tool for these patients.

A propensity score-matched analysis comparing outpatient and short-stay hospitalization to standard inpatient hospitalization following total ankle arthroplasty

Background

Given the trend toward value-based care, there has been increased interest in minimizing hospital length of stay (LOS) after orthopedic procedures. Outpatient total ankle arthroplasty (TAA) has become more popular in recent years; however, research on surgical outcomes of this procedure has been limited. This study sought to employ large sample, propensity score-matched analyses to assess the safety of outpatient and short-stay discharge pathways following TAA.

Methods

The ACS NSQIP database was used to identify 1141 patients who underwent primary and revision TAA between 2007 and 2017. Propensity score matching was used to match patients based on several factors, including age, sex, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, and several comorbidities. The incidence of various 30-day complications was compared between the short and standard LOS groups to assess for any differences in short-term outcomes.

Results

A total of 892 patients were included in the final propensity score-matched analysis, with 446 patients in each group. The short LOS group had a significantly lower rate of medical complications (0.2% vs. 2.5%, p = 0.006) and non-home discharge (1.3% vs. 12.1%, p < 0.001). There was no significant difference in operative complications (0.4% vs. 1.8%, p = 0.107), unplanned readmission (0.4% vs. 1.1%, p = 0.451), reoperation (0.2% vs. 0.4%, p > 0.999), return to the OR (0.2% vs. 0.9%, p = 0.374), or mortality (0.7% vs. 0.0%, p > 0.249) between the short and standard LOS groups.

Conclusions

Outpatient and short-stay hospitalization had comparable safety to standard inpatient hospitalization after TAA. Outpatient or short-stay TAA should be considered for patients with low risk of short-term complications.

Agonizing and Expensive: A Review of Institutional Costs of Ankle Fusion Nonunions

Nonunion after ankle arthrodesis requiring revision is a challenging operative complication, and bone graft substitutes are costly. This study sought to summarize all institutional expenditures related to the revision of an ankle fusion nonunion, presuming that cost and skin-to-skin time would exceed those of the index surgery. The electronic records from 2 foot and ankle centers were reviewed, leading to a list of patients with 2 or more entries for tibiotalar fusions being generated. A total of 24 cases were found to match the criteria. Demographic factors and skin-to-skin time of the remaining patients were compiled. This cohort included 24 patients (6 female and 18 male) with a mean age of 64 years and body mass index of 30.4 kg/m². Supplemental clinic visits and investigations were included either after computed tomography to assess union or 365 days after index surgery. Total cost of the revision was calculated from billing codes, length of operation, and period of hospitalization. Postrevision outpatient fees were included as well. The revisions were performed open in all cases, and 21 patients received autograft and/or bone substitute. Mean postoperative hospitalization was 3 days. The additional costs (in US dollars) associated with nonunion were $1061 for imaging, $627 for prerevision visits, $3026 for the revision, $3432 for the hospital stay, and $1754 for postrevision follow-up. The total mean amount was $9683, equivalent to 9 nights of acute inpatient stay. Mean index skin-to-skin time was 114 minutes, being 126 minutes for revisions (P=.26). Additional care related to ankle fusion nonunion represents a financial burden equivalent to 9 nights of acute inpatient stay. The use of an orthobiologic would need to be less than $436 to be cost saving. Revision surgery is not significantly longer intraoperatively than index surgery. [Orthopedics. 2020;43(4):e219-e224.].

Compensatory Motion of the Subtalar Joint Following Tibiotalar Arthrodesis: An in Vivo Dual-Fluoroscopy Imaging Study

BACKGROUND

Tibiotalar arthrodesis is a common treatment for end-stage tibiotalar osteoarthritis, and is associated with a long-term risk of concomitant subtalar osteoarthritis. It has been clinically hypothesized that subtalar osteoarthritis following tibiotalar arthrodesis is the product of compensatory subtalar joint hypermobility. However, in vivo measurements of subtalar joint motion following tibiotalar arthrodesis have not been quantified. Using dual-fluoroscopy motion capture, we tested the hypothesis that the subtalar joint of the limb with a tibiotalar arthrodesis would demonstrate differences in kinematics and increased range of motion compared with the subtalar joint of the contralateral, asymptomatic, untreated ankle.

METHODS

Ten asymptomatic patients who had undergone unilateral tibiotalar arthrodesis at a mean (and standard deviation) of 4.0 ± 1.8 years previously were evaluated during overground walking and a double heel-rise task. The evaluation involved markerless tracking with use of dual fluoroscopy integrated with 3-dimensional computed tomography, which allowed for dynamic measurements of subtalar and tibiotalar dorsiflexion-plantar flexion, inversion-eversion, and internal-external rotation. Range of motion, stance time, swing time, step length, and step width were also measured.

RESULTS

During the early stance phase of walking, the subtalar joint of the limb that had been treated with arthrodesis was plantar flexed (-4.7° ± 3.3°), whereas the subtalar joint of the untreated limb was dorsiflexed (4.6° ± 2.2°). Also, during the early stance phase of walking, eversion of the subtalar joint of the surgically treated limb (0.2° ± 2.3°) was less than that of the untreated limb (4.5° ± 3.2°). During double heel-rise, the treated limb exhibited increased peak subtalar plantar flexion (-7.1° ± 4.1°) compared with the untreated limb (0.2° ± 1.8°).

CONCLUSIONS

A significant increase in subtalar joint plantar flexion was found to be a primary compensation during overground walking and a double heel-rise activity following tibiotalar arthrodesis.

CLINICAL RELEVANCE

Significant subtalar joint plantar flexion compensations appear to occur following tibiotalar arthrodesis. We found an increase in subtalar plantar flexion and considered the potential relationship of this finding with the increased rate of subtalar osteoarthritis that occurs following ankle arthrodesis.

Ankle fusion in patients with chronic hepatitis C

BACKGROUND

It appears that both the incidence and survival of patients infected with hepatitis C have recently demonstrated a significant increase. The goal of this investigation was to determine the associated perioperative risks associated with ankle arthrodesis in this growing population.

METHODS

The Healthcare Cost and Utilization Project State Inpatient Databases identified patients with chronic hepatitis C infection who underwent ankle arthrodesis between January 2009 and December 2013. International Classification of Diseases, Ninth Revision, codes were used to define the primary composite outcome of death or postoperative complication. Logistic models with frequency weights were used to compare propensity matched groups.

RESULTS

7339 patients met inclusion criteria. Of these, 157 patients had a history of chronic Hepatitis C infection. After performing a propensity score match, the final analytic cohort was 157 in the Hepatitis C group and 386 in the non-Hepatitis C group. There was no statistically significant differences in complications between patients with chronic Hepatitis C undergoing ankle fusion and those without Hepatitis C at any post-operative time point (inpatient, 30 days, or 90 days).

DISCUSSION

Patients with chronic hepatitis C infection undergoing ankle arthrodesis are not at an elevated risk of inpatient, thirty, and ninety day postoperative complications compared to patients without chronic HCV infections. Patients with chronic hepatitis C did not have an increased risk of surgical site infection or mortality at any time point.

LEVEL OF EVIDENCE

Prognostic Level III.