Single-Surgeon Experience and Complications of a Fixed-Bearing Total Ankle Arthroplasty

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.

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.

Learning curve of total ankle arthroplasty: a systematic review

INTRODUCTION

Together with ankle arthrodesis, total ankle arthroplasty is now accepted as a first-line intervention in the management of end-stage arthritis of the ankle. The evidence regarding how outcomes are affected by surgeon experience is inconsistent; we performed a systematic review to evaluate the effect of a learning curve in total ankle arthroplasty outcomes.

METHODS

An electronic database search was performed in PubMed, Embase, ISI Web of Science and Cochrane trials. Two reviewers independently conducted a two-stage title/abstract and full text screening. English-language original research studies comparing patient-reported outcome measures (PROMs), complication/revision rates, operative time, length of stay or radiation exposure according to surgeon experience were included. Quality assessment was performed using the methodological index for non-randomised studies.

RESULTS

All but one included study report either improved PROMs, reduced complication/revision rate, reduced hospital stay length/operative time or reduced radiation exposure with increasing surgeon experience. However, the majority of these findings lack statistical significance. Two studies assessing the plateau of the learning curve report a wide range of plateau thresholds between 9 and 39 cases.

CONCLUSION

This review finds a largely non-significant trend towards improvements in PROMs, complication, and revision rates with improved surgeon experience. The lack of statistical significance in a number of studies may be partially explained by methodological flaws, with more suitably designed studies reporting significant improvements. Future research into the effect of advancements in implant design and insertion guides is required to further characterise the magnitude of the learning curve and guide both mitigation and learning strategies.

Salto Talaris Fixed-Bearing Total Ankle Arthroplasty: Long-Term Results at a Mean of 10.7 Years

Background

Total ankle arthroplasty (TAA) has become increasingly popular in the treatment for end-stage ankle arthritis in recent decades. However, there is limited evidence regarding the long-term clinical outcomes and complication rates of modern TAA implants.

Methods

This study presents a follow-up on a previous cohort involving 78 patients (81 ankles) who underwent Salto Talaris fixed-bearing TAA to treat end-stage arthritis, with a mean postoperative follow-up of 5.2 years. The aim of this follow-up study was to assess the radiographic (33 patients, 35 ankles) and clinical (48 patients, 50 ankles) results from the original cohort at a mean of 10.7 years (range, 7.8-14 years).

Results

At a mean of 10.7 years, the Kaplan-Meier estimated survivorship was 84.2% (95% CI, 71.9%-98.6%). For the patients reviewed, we did not find any change in patient-reported outcomes between an average 5- and 11-year follow-up. Measured total range of motion and plantarflexion did not change between 1 and 11 years, but dorsiflexion was measured as decreasing by an average of 4 degrees (P < .02).

Conclusion

In this longer-term follow-up of a limited cohort, we found that Salto Talaris fixed-bearing TAA demonstrated good long-term survival with relatively low rates of revision or other complications. Patient-reported outcome and range of motion measures revealed good stability.

Level of Evidence

Level III, therapeutic.

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.

Midterm Clinical Outcomes, Radiographic Outcomes, and Survivorship of the Infinity Total Ankle Arthroplasty

BACKGROUND

The Infinity Total Ankle Arthroplasty (Stryker, Mahwah, NJ) is a low-profile fixed-bearing implant first introduced in 2014. Although the short-term survivorship (2-4 years follow-up) and complication rates of the Infinity TAA have been reported, there are limited midterm outcome reports. The aim of this study was to describe the survivorship and clinical outcomes of a single-center experience with the Infinity implant at minimum 5-year follow-up.

METHODS

Retrospective review of 65 ankles that underwent primary total ankle arthroplasty (TAA) with the Infinity implant was conducted. Mean clinical follow-up was 6.5 years (range, 5.0-8.0). Preoperative and postoperative radiographs were measured to assess tibiotalar alignment, periprosthetic lucencies, and cysts. Preoperative, 2-year, and 5-year postoperative Foot and Ankle Outcome Score (FAOS) subscores were compared to assess midterm clinical outcomes. Survivorship assessment was determined by removal of 1 or both metallic implant components.

RESULTS

Survivorship of the implant was 93.8% at final follow-up. There were 4 revisions: 2 for tibial implant loosening, 1 for talar loosening, and 1 for loosening of both components. Three of the 4 revisions occurred within the first 2 years following implantation, and the last failure occurred at 7 years postoperatively. There were 11 reoperations in 10 (15%) ankles and 3 wound complications. There were 17 ankles (26.2%) with radiographic abnormalities around the implants, including 14 cases with tibial component lucencies and 4 cases of periimplant cysts. FAOS outcome measurement showed general stability between 2 and 5 years and substantial improvement from preoperative status.

CONCLUSION

To date this study is the largest midterm report on the Infinity total ankle prosthesis, with 65 implants at a mean follow-up of 6.5 years. We found good midterm implant survivorship, and patients experienced significant improvements in FAOS outcome scores and radiographic alignment at final follow-up.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

What is the best way for an inexperienced surgeon to learn total ankle arthroplasty?

BACKGROUND

Previous reports on the learning curve of total ankle arthroplasty (TAA) revealed that inexperienced surgeons should be more careful about operative indications and procedures during the learning curve period. Patients who underwent surgery with inexperienced surgeons may be associated with inferior clinical outcomes, such as frequent complications. This study aimed to evaluate the effect of the participation of experienced surgeons as assistants on the results of TAA performed by inexperienced surgeons.

METHODS

Surgeons whose experience in performing TAA included less than 15 ankles were defined as inexperienced surgeons; on the other hand, those whose experience included more than 20 ankles were defined experienced surgeons in this study. Thirteen ankles operated by inexperienced surgeons, with an experienced surgeon who participated as an assistant, were assigned to the inexperienced group. Fifteen ankles operated on by an experienced surgeon were assigned to the experienced group. TNK Ankle (Kyocera, Kyoto, Japan) was used for all experiments. The coronal and sagittal alignments and the size of the tibial component relative to the tibial shaft were measured. Preoperative and postoperative Japanese Society for Surgery of the Foot (JSSF) and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) were used for clinical assessment.

RESULTS

There were two malleolar fractures during the operation in both groups, and there were no cases of revision surgery. There were no significant differences in the coronal and sagittal tibial component alignment and size between the groups. The JSSF and SAFE-Q improved. There were no significant differences between groups, except for the preoperative JSSF score.

CONCLUSIONS

During the learning curve period, careful surgical indications and surgeries are desired. However, we found that when experienced surgeons participated as assistants, favorable results could be expected even when inexperienced surgeons performed the surgery.

LEVEL OF EVIDENCE

Ⅲ.

Short-Term Complications and Outcomes of the Cadence Total Ankle Arthroplasty

BACKGROUND

Total ankle arthroplasty (TAA) is an increasingly popular option for the operative treatment of ankle arthritis. The Cadence TAA entered clinical use in 2016 and was designed to address common failure modes of prior systems. We report early complications and radiographic and clinical outcomes of this total ankle system at a minimum of 2 years of follow-up.

METHODS

We performed a retrospective review of a consecutive cohort of patients undergoing primary Cadence TAA by a single surgeon from 2016 to 2017. Complications and reoperations were documented using the American Orthopaedic Foot & Ankle Society (AOFAS) TAA reoperation coding system. Patients completed the Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) and Sport subscales, SF-12 Mental (MCS) and Physical (PCS) Component Summaries, and visual analog scale (VAS) pain rating (0-100). Radiographic evaluation was performed to assess postoperative range of motion (ROM) of the sole of the foot relative to the long axis of the tibia, alignment, and implant complications.

RESULTS

Fifty-eight patients with a mean age of 63.3 years and mean body mass index of 31.9 kg/m² were included. Twelve of 58 patients (20.7%) underwent an additional procedure(s) within 2 years, including 3 (5.2%) who required removal of one or both components, 2 for infection and 1 for osteolysis. Forty-three patients were followed for a minimum of 2 years with radiographic imaging; 1 patient's (2.3%) radiographs had signs of peri-implant osteolysis, with no cases demonstrating loosening or subsidence. FAAM-ADL, FAAM-Sport, SF-12 PCS, and VAS pain scores all improved at a mean of 27.4 months postoperatively, with mean score changes (± SD) of 16.3 (± 22.0), 25.3 (± 24.5), 6.0 (± 11.1), and -32.3 (± 39.8), respectively. Radiographic analysis revealed that average coronal alignment improved from 6.9 degrees from neutral preoperatively to 2.3 degrees postoperatively. The average ROM of the foot relative to the tibia was 36.5 degrees total arc of motion based on lateral radiographs.

CONCLUSION

Early experience with this 2-component total ankle replacement was associated with a high component retention rate, improved coronal plane alignment, good postoperative ROM, radiographically stable implants, and improved patient function.

LEVEL OF EVIDENCE

Level IV, case series.

Revision Rates After Total Ankle Replacement: A Comparison of Clinical Studies and Arthroplasty Registers

BACKGROUND

The aim of this study was to assess the outcome of total ankle replacement (TAR) regarding revision rates by comparing clinical studies of the last decade to data displayed in arthroplasty registers. The secondary aim was to evaluate whether dependent clinical studies show a superior outcome to independent publications. Additionally, revision rates of mobile bearing implants (MB-TARs) were compared to those of fixed bearing implants (FB-TARs).

METHODS

Clinical studies on TARs between 2010 and 2020 were systematically reviewed, with the endpoint being a revision for any reason. The parameter "revision rate per 100 observed component years (CYs)" was calculated for each publication. The pooled revision rate for clinical studies was compared to the data reported in arthroplasty registers. In a second step, revision rates were subdivided and analyzed for independent and dependent publications and for FB-TARs and MB-TARs.

RESULTS

A total of 43 publications met the inclusion criteria comprising 5806 TARs. A revision rate of 1.8 per 100 observed CYs was calculated, corresponding to a 7-year revision rate of 12.6%. The 3 arthroplasty registers included showed revision rates ranging from 8.2% to 12.3% after 7 years. No significant difference between dependent and independent publications nor between FB-TARs and MB-TARs was detected.

CONCLUSION

Revision rates of clinical studies and arthroplasty registers are comparable. Surgeons can compare their own revision rates with those from this study. Dependent studies do not seem to be biased, and no superiority for one bearing type can be described.

LEVEL OF EVIDENCE

Level III, systematic review of level III studies.

Three-Year Rates of Reoperation and Revision Following Mobile Versus Fixed-Bearing Total Ankle Arthroplasty: A Cohort of 302 Patients with 2 Implants of Similar Design

BACKGROUND

Currently, the implants utilized in total ankle arthroplasty (TAA) are divided between mobile-bearing 3-component and fixed-bearing 2-component designs. The literature evaluating the influence of this mobility difference on implant survival is sparse. The purpose of the present study was therefore to compare the short-term survival of 2 implants of similar design from the same manufacturer, surgically implanted by the same surgeons, in fixed-bearing or mobile-bearing versions.

METHODS

All patients were enrolled who underwent TAA with either the mobile-bearing Salto (Tornier and Integra) or the fixed-bearing Salto Talaris (Integra) in 3 centers by 2 surgeons between January 2004 and March 2018. All patients who underwent TAA from January 2004 to April 2013 received the Salto implant, and all patients who underwent TAA after November 2012 received the Salto Talaris implant. The primary outcome was time, within 3 years, to first all-cause reoperation, revision of any metal component, and revision of any component, including the polyethylene insert. Secondary outcomes included the frequency, cause, and type of reoperation.

RESULTS

A total of 302 consecutive patients were included, of whom 171 received the mobile-bearing and 131 received the fixed-bearing implant. The adjusted hazard ratio for all-cause reoperation was 1.42 (95% confidence interval [CI], 0.67 to 3.00; p = 0.36); for component revision, 3.31 (95% CI, 0.93 to 11.79; p = 0.06); and for metal component revision, 2.78 (95% CI, 0.58 to 13.33; p = 0.20). A total of 31 reoperations were performed in the mobile-bearing group compared with 14 in the fixed-bearing group (p = 0.07). More extensive reoperation procedures were performed in the mobile-bearing group.

CONCLUSIONS

With the largest comparison of 2 implants of similar design from the same manufacturer, the present study supports the use of a fixed-bearing design in terms of short-term failure. We found a 3-times higher rate of revision among mobile-bearing implants compared with fixed-bearing implants at 3 years after TAA. Reoperations, including first and subsequent procedures, tended to be less common and the causes and types of reoperations less extensive among fixed-bearing implants.

LEVEL OF EVIDENCE

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

Early Outcomes and Complications Following Initiation of a Total Ankle Arthroplasty Program

Background:

Surgeons who lack experience with total ankle arthroplasty (TAA) may remain hesitant to introduce this procedure owing to previously published results of high complication rates during initial cases. The purpose of the present study was to report the development of a TAA program through intermediate outcomes and complications for an initial consecutive series of TAA patients of a single community-based foot and ankle fellowship–trained orthopedic surgeon with little TAA experience using a co-surgeon with similar training and TAA exposure.

Methods:

The initial 20 patients following third-generation TAA with a single surgeon were reviewed. Clinical outcomes were measured and radiographs were evaluated to determine postoperative implant and ankle position. Complications were also measured including intraoperative, early (<3 months), and intermediate postoperative complications.

Results:

With a minimum follow-up of 2 years and average follow-up of 51 months (range 24-70 months), the mean American Orthopaedic Ankle & Foot Society Ankle-Hindfoot score was 87.7 (59-100) and VAS was 1.0 (0-5.5). All patients were improved following TAA. Radiographic evaluation demonstrated no evidence of component malalignment or ankle joint incongruity. There were no intraoperative complications nor any wound complications. Three patients returned to the operating room for placement of medial malleolar screw placement, and 1 had asymptomatic tibial component subsidence.

Conclusions:

Orthopedic surgeons with a proper background and updated training may be able to perform TAA with good outcomes. A TAA program was developed to define minimum training criteria to perform this procedure in our community. Our complication rate is consistent with those reported in the literature for experienced TAA centers, which contrasts previous literature suggesting increased complication rates and worse outcomes when surgeons perform initial TAAs. Utilization of an orthopedic co-surgeon was felt to be instrumental in the success of the program.

Level of Evidence:

Level IV, retrospective case series.

Radiographic and Clinical Outcomes of the Salto Talaris Total Ankle Arthroplasty

BACKGROUND

The Salto Talaris is a fixed-bearing implant first approved in the US in 2006. While early surgical outcomes have been promising, mid- to long-term survivorship data are limited. The aim of this study was to present the survivorship and causes of failure of the Salto Talaris implant, with functional and radiographic outcomes.

METHODS

Eighty-seven prospectively followed patients who underwent total ankle arthroplasty with the Salto Talaris between 2007 and 2015 at our institution were retrospectively identified. Of these, 82 patients (85 ankles) had a minimum follow-up of 5 (mean, 7.1; range, 5-12) years. The mean age was 63.5 (range, 42-82) years and the mean body mass index was 28.1 (range, 17.9-41.2) kg/m². Survivorship was determined by incidence of revision, defined as removal/exchange of a metal component. Preoperative, immediate, and minimum 5-year postoperative AP and lateral weightbearing radiographs were reviewed; tibiotalar alignment (TTA) and the medial distal tibial angle (MDTA) were measured to assess coronal talar and tibial alignment, respectively. The sagittal tibial angle (STA) was measured; the talar inclination angle (TIA) was measured to evaluate for radiographic subsidence of the implant, defined as a change in TIA of 5 degrees or more from the immediately to the latest postoperative lateral radiograph. The locations of periprosthetic cysts were documented. Preoperative and minimum 5-year postoperative Foot and Ankle Outcome Score (FAOS) subscales were compared.

RESULTS

Survivorship was 97.6% with 2 revisions. One patient underwent tibial and talar component revision for varus malalignment of the ankle; another underwent talar component revision for aseptic loosening and subsidence. The rate of other reoperations was 21.2% (n = 18), with the main reoperation being exostectomy with debridement for ankle impingement (n = 12). At final follow-up, the average TTA improved 4.4 (± 3.8) degrees, the average MDTA improved 3.4 (± 2.6) degrees, and the average STA improved 5.3 (± 4.5) degrees. Periprosthetic cysts were observed in 18 patients, and there was no radiographic subsidence. All FAOS subscales demonstrated significant improvement at final follow-up.

CONCLUSIONS

We found the Salto Talaris implant to be durable, consistent with previous studies of shorter follow-up lengths. We observed significant improvement in radiographic alignment as well as patient-reported clinical outcomes at a minimum 5-year follow-up.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Total Ankle Arthroplasty Is Safer Than Total Hip and Knee Arthroplasty in the Early Postoperative Period

BACKGROUND

Total hip and knee arthroplasty (THA and TKA) are performed more commonly than total ankle arthroplasty (TAA), so patients and the orthopaedic community are more familiar with the likelihood of complications after THA and TKA than after TAA. The present study places early complication rates after TAA in the context of those after THA and TKA.

METHODS

Patients who underwent TAA, THA, or TKA during 2006 to 2016 as part of the National Surgical Quality Improvement Program were identified. Multivariate regression was used to compare procedures with adjustment for baseline and anesthesia characteristics.

RESULTS

One hundred thirty-eight thousand three hundred twenty-five patients underwent THA, 223,587 TKA, and 839 TAA. The total complication rate was lower for TAA (2.98%) compared with THA (4.92%, P = 0.011) and TKA (4.56%, P = 0.049). Similarly, the rate of blood transfusion was lower for TAA (0.48%) compared with THA (9.66%) and TKA (6.44%, P < 0.001 for each). The rate of additional surgery was lower for TAA compared with THA (0.48% versus 1.79%, P = 0.007). Finally, the rate of readmission was lower for TAA (1.45%) compared with THA (3.66%, P = 0.002) and TKA (3.40%, P = 0.005).

DISCUSSION

Patients can be counseled that relative to THA and TKA, TAA is safer in the perioperative period, with lower rates of adverse events, blood transfusion, additional surgery, and hospital readmission.

Positive and negative factors for the treatment outcomes following total ankle arthroplasty? A systematic review

BACKGROUND

Patient selection, surgeon's experience and implant design play an integral role and affect the treatment outcomes of total ankle arthroplasty (TAA). The aims of this study were to investigate the positive and negative attributes that correlate with different clinical and radiographic outcomes.

METHODS

Eight-nine studies matched the inclusion criteria: (1) studies of primary TAA with uncemented prosthesis; (2) mean follow-up of no less than 2-year; (3) reports of clinical and radiographic outcomes, and exclusion criteria: (1) non-English study; (2) more than one type of prosthesis without separated data; (3) kin studies with shorter follow-up or smaller cohort. Age, etiology, preoperative deformity, surgeon's experience, follow-up duration and prosthetic type were studied with respect to different outcomes by mixed-effects logistic regression analysis.

RESULTS

Patients factor: older patients reported less pain or stiffness and demonstrated less radiographic loosening which did not require additional surgical intervention. More traumatic arthritis experienced adjacent joints degeneration after TAA. Surgeon factor: less experienced surgeons had more intraoperative complications. Lack of experience for complications management without implant retrieval during early period might result in more revisions or fusion was done. Prosthetic factor: updated instrumentation decreased malalignment. If the polyethylene (PE) insert was significantly narrower than the metal components more implant instability and subsequent severe particulate wear was seen. Designs with flat-on-flat articulation and ridge at the center of the talar component associated with more PE fracture. Minimal bone resection reduced postoperative fractures. A flat cut of the tibial component and a flat undersurface with press-fit by two screws or pegs of the talar component demonstrated less postoperative fractures, whereas a syndesmosis fusion and a small triangular shape with one central fin of the talar component experienced more loosening which did not require additional surgery. Anatomic conical shape of the talar component seemed to reduce adjacent joint degeneration. Finally, fewer failures were found in patients who received HINTEGRA and Salto Talaris.

CONCLUSIONS

Based on our investigation, some positive and negative factors for different clinical and radiographic outcomes were found, which should be taken into consideration in clinical practice and ankle implant design.

[Development and clinical application of ankle prosthesis]

OBJECTIVE

To review the development and clinical application of ankle prosthesis.

METHODS

The recent literature on ankle prosthesis design and clinical application was reviewed and analyzed.

RESULTS

Compared with the hip and knee prostheses, the ankle prosthesis develops slowly and has been developed to the third generation. The ankle joint has a special structure of multi-axis movement. The design of the first and second generations of prostheses is not conformed to the biomechanics of the ankle. The third generation of prosthesis is more conform to the characteristics of ankle biomechanics, with high postoperative survival rate and satisfactory clinical outcome.

CONCLUSION

At present, the survival rate of ankle prosthesis is low, and there is still much room for improvement in biomechanics, materials, and other aspects.

Recent National Trends and Outcomes in Total Ankle Arthroplasty in the United States

Total ankle arthroplasty (TAA) is an evolving option for treating ankle arthritis. We assessed the national trends in usage and perioperative outcomes of TAA in the United States. International Classification of Diseases, 9th revision (ICD-9), codes were used to search the National Hospital Discharge Survey database for TAA from 1997 to 2010. Patient demographics, comorbidities, hospitalization length, discharge disposition, blood transfusion, lower extremity deep vein thrombosis, pulmonary embolism, and mortality data were gathered. Trends were evaluated using linear regression with Pearson's correlation coefficient, and statistical comparisons were performed using Student's t test and z-test for proportions with significance at p = .05. We identified 120 patients with TAA. TAA demonstrated a positive correlation with time (r = 0.57), significantly increasing from 2.4 cases per 100,000 admissions from 1997 to 2003 to 3.5 cases per 100,000 from 2004 to 2010 (p = .04). The mean age was 57.8 (range 19 to 83) years. The mean number of comorbidities was 4.5 (range 1 to ≥7). Although patient age remained stable (p = .21), the mean number of comorbidities significantly increased from 4.0 from 1997 to 2003 to 4.8 from 2004 to 2010 (p = .02); 8 patients (6.7%) had diabetes, 71 (59.2%) had primary osteoarthritis, and 35 (29.2%) had posttraumatic arthropathy. The mean length of stay significantly decreased from 3.1 to 2.3 days (p = .03). Three patients (2.5%) required a blood transfusion. No deep vein thrombosis or PE was diagnosed. No patients died during the operative admission; 95 patients (87%) were discharged home and 14 (13%) required a skilled rehabilitation facility. Discharge patterns showed no significant change with time (p = .59). Usage of TAA in the United States has increased nearly 50% over the past 14 years. TAA was associated with shorter hospitalization, infrequent rehabilitation facility requirements, and few perioperative complications.

Management of Posttraumatic Ankle Arthritis: Literature Review

PURPOSE OF REVIEW

Trauma is the principle cause of osteoarthritis in the ankle, which is associated with significant morbidity. This review highlights the current literature for the purpose of bringing the reader up-to-date on the management of posttraumatic ankle arthritis, describing treatment efficacy, indications, contraindications, and complications.

RECENT FINDINGS

Recent studies on osteoarthritis have demonstrated variability among anatomic locations regarding the mechanisms and rates of development for posttraumatic osteoarthritis, which are attributed to newly discovered biological differences intrinsic to each joint. Regarding surgical management of posttraumatic ankle arthritis, osteochondral allograft transplantation of the talus, and supramalleolar osteotomies have demonstrated promising results. Additionally, the outpatient setting was found to be appropriate for managing pain following total ankle arthroplasty, associated with low complication rates and no readmission. Management for posttraumatic ankle arthritis is generally progressive. Initial treatment entails nonpharmacologic options with surgery reserved for posttraumatic ankle arthritis refractory to conservative treatment. Patient demographics and lifestyles should be carefully considered when formulating a management strategy, as outcomes are dependent upon the satisfaction of each set of respective criteria. Ultimately, the management of posttraumatic ankle arthritis should be individualized to satisfy the needs and desires, which are specific to each patient.

[Progress of total ankle arthroplasty for end-stage ankle osteoarthritis]

Objective

To review the progress of total ankle arthroplasty (TAA) in treatment of end-stage ankle osteoarthritis (AOA).

Methods

The domestic and foreign literatures about TAA in recent years were reviewed. The current status and progress of TAA were summarized from the results of traditional and computer-assisted TAA clinical outcomes.

Results

End-stage AOA often leads to severe pain and dysfunction, and arthrodesis is still the main selective treatment option. In recent years, with the advancement of surgical techniques and prosthesis design, TAA which can remain joint mobility has increased gradually, and the surgical results also have significant progress. Accurate prosthesis implant and mechanical alignment restoration are critical factors for TAA, and surgery-related malalignment is correlative to the prosthesis failure. Computer assisted patient-specific guide can simplify the TAA procedures and obtain the accuracy of tibia and talus osteotomy.

Conclusion

The clinical efficiency of preoperative CT based patient-specific guide technology for TAA needs further clinical follow-up. Meanwhile, it is necessary to further develop intraoperative navigation and robotic surgery system suitable for TAA.