Early outcomes and radiographic alignment of the Infinity total ankle replacement with a minimum of two year follow-up data

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

INTRODUCTION

Total ankle replacement (TAR) is an effective treatment for end-stage osteoarthritis. The aim of this systematic review was to assess the age of patients undergoing TAR in prospective comparative studies. Our hypothesis is that the age reported in most recent papers might be lower than those reported in older papers.

METHODS

This systematic review was performed using Pubmed, Scopus, EMBASE and Cochrane databases. Only Level I and II studies dealing with TAR were included. Data regarding demographics, study design, number of cohorts in each study, year of publication and year/years in which surgery was performed were extracted. A two-fold analysis was conducted building groups of patients based on the year of publication and creating 1) two groups (before and after the median year) and 2) three groups (using tertiles) in order to compare age of patients operated in different period of times. A comparison was also performed considering the median year of surgery for patients undergoing TAR.

RESULTS

Overall 59 cohorts (42 studies, published between 1999 and 2023; median year of publication: 2017) were included (6397 ankles, 6317 patients, median age 63 years). The difference between the median age for 27 cohorts published until 2016 (weighted median 63 years; IQR, 62.5-64) and the median age for 32 cohorts published after 2017 (weighted median 63.2 years; IQR, 63-67.8) was not statistically significant (p = 0.09). The division in tertiles did not reveal any significant change in the weighted median age at surgery (T1 (1999-2014; 63.2 years; IQR, 62.8-64.1), T2 (2015-2018; 63 years; IQR,63-63.5) and T3 (2019-2023; 63.2 years; IQR, 62.6-67.8)) over time (p = 0.65). The median age of patients operated between 1999 and 2008 vs 2009 and 2023 (data from 48 cohorts) was not different either (p = 0.12).

CONCLUSION

According to this review of prospective studies published between 1999 and 2023, the median age for patients undergoing TAR over the last two decades has been 63 years, remaining steady with no significant changes over time.

LEVEL OF EVIDENCE

Level II - systematic review including Level I and Level II studies.

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

Introduction

Total ankle replacements (TARs) is emerging as a successful alternate treatment option to arthrodesis for surgical treatment of end stage ankle arthritis. This has led to manufacturers producing a selection of implants. There is wide variations in post-operative rehab protocols being adopted for treatment following TAR surgery. This depends on choice of implants and manufacturer recommendations too. Following the author's investigation, a lack of standardisation between manufacturer post-operative protocols was identified. The aim of this project was to analyse similarities and differences in guidelines for: choice of immobilisation, weight-bearing (WB) status, of range of movement (ROM) exercises and Physiotherapy.

Method

Current commonly used TAR implants in the UK were identified using National Joint Registry's 2020 Annual Report. Additional implants were included after accessing data regarding the TAR market. Individual company websites were researched for information available on public domain for post op management guidelines and the results were summarised.

Results

Only 7 implants were reviewed as 6 companies either did not provide post-operative protocols or recommended a surgeon guided rehabilitation process. Different manufacturers allow partial WB by week 2, week 3 and week 7. One protocol suggested full WB from week 4 whereas two others suggested it from week 6. Choices of immobilisation varied as one company suggested casting alone for 6 weeks, two suggest casting followed by a period in a boot, one suggests splinting and a boot and one uses all 3 types of immobilisations. ROM exercises were mentioned by three manufacturers and were encouraged from week 2 and 3. Physiotherapy was mentioned in four protocols, two of which suggest intervention from week 6, one from week 7 and the other mentions the importance of therapy rather than specific timelines.

Conclusion

There are differences between post op TAR guidelines from the implant manufacturers regarding the categories analysed. The variation in the data collected makes it challenging to suggest a singular protocol to be followed after TAR surgery.

Early experience with a 3-D printed porous surface, fixed-bearing, total ankle arthroplasty: A minimum of 2-year follow-up

BACKGROUND

This is a pilot study reviewing patients undergoing ankle replacement with the 3-D printed INFINITY™ with ADAPTIS™ total ankle arthroplasty (TAA) system.

METHODS

A retrospective review was conducted of patients with a minimum two-year follow-up who underwent TAA with the INFINITY™ with ADAPTIS™ implant system. Outcome measures include implant survivorship, complications with subsequent reoperations, patient reported outcomes, and radiologic subsidence or radiolucency.

RESULTS

Thirty patients were included with median follow-up of 26 months (range, 24-36). Implant survival rate was 90% (27/30). Two patients experienced linear radiolucency > 2 mm: one required a revision TAA secondary to tibial subsidence; the other patient was asymptomatic and nonprogressive on serial radiographs. No cystic radiolucencies > 5 mm were identified. VAS, PROMIS PF, and FADI scores improved significantly.

CONCLUSION

TAA performed with the 3-D printed INFINITY™ with ADAPTIS™ implant technology led to ninety percent short term implant survivorship and improvement in patient reported outcomes with comparable results to other 4th generation arthroplasty systems as a treatment modality for end-stage ankle arthritis.

LEVEL OF EVIDENCE

Level III, Retrospective cohort study, Prognostic.

Contemporary modern total ankle arthroplasty (TAA): A systematic review and meta-analysis of indications, survivorship and complication rates

BACKGROUND

This study evaluates the clinical outcomes of contemporary total ankle arthroplasty (TAAs) to primarily establish the current benefits and risks to facilitate informed decision making to secondarily establish if improvements are seen between subsequent generations of implants, bearing philosophy, and associated surgical technique.

METHODS

A systematic review and meta-analysis of published data from January 2000 to January 2020 was conducted following PRISMA guidelines.

INCLUSION CRITERIA

English language papers, adult population, ≥20 ankles with a minimum follow up ≥24 months, pre- and post-operative functional scores available. Ankle implants were characterised by generations, which were determined from the original studies and confirmed based on literature set definitions.

RESULTS

A total of 4642 TAAs in 4487 patients from 51 studies were included. The mean age was 61.9-years and follow up 57.8-months. Overall, 10-year survivorship rates were 77.63 %, with mobile bearing designs showing a small but significant advantage. Improved survivorship favoured the most modern implants at both two (p < 0.05), and 10-years (p < 0.01). The relative risk of a complication occurring improved with the evolution of implants e.g., nerve injury, and post-operative complications such as fracture, wound complications (e.g., dehiscence or heamatoma) and radiological abnormalities (e.g., radiolucencies, heterotopic bone formation and aseptic loosening). However, surgical site infection, and intra-operative fracture rates remain implant independent.

CONCLUSIONS

Modern TAA offers improved survivorship, even with a trend to lower mean implantation age, similar complexity and ever changing indications. It would appear that implant evolution has reduced risks, especially those associated with revision, without affecting functional outcomes.

Comparing Rates of Radiographic Baseplate Loosening Between Cement and Cementless INFINITY Total Ankle Prostheses

INTRODUCTION

Total ankle replacement is indicated for end-stage ankle osteoarthritis. Periprosthetic radiolucency, from separation between the bone and implant, is suggested to be indicative of potential prosthesis failure risk. Anchoring implants with cement may mitigate this. This study aimed to compare rates of periprosthetic radiolucency between patients with cement-affixed and cementless implants.

METHODS

A retrospective analysis was performed on 28 patients who underwent total ankle replacement with the INFINITY Total Ankle System (Wright Medical, Memphis, Tennessee) implant between January 2016 and May 2022. Anteroposterior, mortise, and lateral ankle X-rays were reviewed by 2 independent reviewers for tibiotalar angle, talar tilt, and periprosthetic radiolucency. The Wilcoxon rank-sum test and chi-square test were performed.

RESULTS

The incidence of periprosthetic radiolucency at the most recent follow-up did not significantly differ between cement and cementless groups (57.1% in both groups, P = 1.0). Follow-up tibiotalar and talar tilt angles were not significantly different (P > .51 for all comparisons).

CONCLUSIONS

Patients with cemented implants had a similar incidence of periprosthetic radiolucency compared with patients with cementless prostheses. Understanding of long-term clinical outcomes will help inform optimal operative approaches for ankle prostheses.

LEVELS OF EVIDENCE

Therapeutic, Level III, Retrospective cohort study.

Two-Year Survivorship and Patient-Reported Outcomes of a Prospectively Enrolled Cohort of INFINITY Total Ankle Arthroplasties

BACKGROUND

The INFINITY total ankle implant is a widely and successfully used option for total ankle arthroplasty. The purpose of this study is to assess the 2-year survivorship, complication rates, patient-reported outcomes, and radiologic findings of prospectively enrolled patients undergoing a fixed-bearing total ankle arthroplasty (TAA). This study sought to determine if factors such as traditional vs patient-specific instrumentation, preoperative degree of arthritis, deformity, or etiology of arthritis impact surgical or clinical outcomes.

METHODS

A total of 143 prospectively enrolled patients (148 ankles) underwent TAA with a fixed-bearing total ankle implant between 2017 and 2019 at 9 different institutions by 9 different surgeons. A total of 116 completed 2-year follow-up. Patients were stratified by instrumentation used, degree of preoperative deformity, the Canadian Orthopaedic Foot and Ankle Society (COFAS) grading system, and etiology of arthritis. Outcomes used included implant survivorship and adverse events within 2 years of surgery. Additionally, patient-reported outcomes and radiographs were collected at 6-month, 1-year, and 2-year postoperatively. PROMs used included Ankle Osteoarthritis Score (AOS), Patient-Reported Outcomes Measurement Information System (PROMIS) global health score, the Foot and Ankle Outcome Score (FAOS), and patient satisfaction (rated from excellent to poor).

RESULTS

Implant survivorship at 2 years was 97.79%. There were 17 reoperations (11.5%), with 4 of the implants requiring revision (2.7%). Significant improvements in all PROMs were observed among all subgroups at all postoperative time points without significant variation between subgroups. Patients classified as COFAS type 2 arthritis preoperatively demonstrated significantly more improvement in FAOS Total Symptom Score at the 1- and 2-year measurements than COFAS type 3 patients at both time points.

CONCLUSION

Total ankle arthroplasty with a fixed-bearing implant system is a safe and reliable treatment option for patients with end-stage arthritis regardless of degree of deformity or COFAS grading.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

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.

Two to Five-Year Outcomes of Total Ankle Arthroplasty with the Infinity Fixed-Bearing Implant: A Concise Follow-up of a Previous Report

LEVEL OF EVIDENCE

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

Bilateral lower extremity gait and function after unilateral total ankle arthroplasty: a case report

BACKGROUND

End-stage ankle osteoarthritis is one of the leading causes of chronic disability in North America. The main purpose of this case report was to describe the functional recovery of a person following total ankle arthroplasty (TAA) surgery using the INFINITY™ system for end stage osteoarthritis of the left ankle.

CASE DESCRIPTION

We report a case of a 55-year-old male who had attempted conservative management for end stage ankle osteoarthritis in his left ankle but ultimately elected to undergo TAA using The INFINITY™ Total Ankle System. He not only had significant left ankle pain limiting his daily function, but also had developed severe right knee pain. We performed gait analysis both before and 6 months after his TAA surgery to examine the sagittal and frontal-plane motions of bilateral ankle, knee, and hip joints during gait.

OUTCOMES

At 6 months post-surgery, the patient demonstrated a 44-point improvement in his Foot and Ankle Outcome questionnaire scores as well as an increase in both left knee and left ankle motion in the sagittal and frontal planes. Kinematic deviations in the left ankle, hip, and knee joints during gait also reduced post-surgery. Despite improvement in his left ankle and overall function, the participant's right knee pain and altered kinematics of the right limb during gait worsened after surgery.

DISCUSSION

Interventions, either before or after ankle surgery, should consider bilateral lower extremities simultaneously in order to optimize patient care and minimize future secondary complications for individuals with unilateral ankle osteoarthritis.

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.

Outcomes in Ankle Replacement Study (OARS)

Aims

The aim of this study was to capture 12-month outcomes from a representative multicentre cohort of patients undergoing total ankle arthroplasty (TAA), describe the pattern of patient-reported outcome measures (PROMs) at 12 months, and identify predictors of these outcome measures.

Methods

Patients listed for a primary TAA at 19 NHS hospitals between February 2016 and October 2017 were eligible. PROMs data were collected preoperatively and at six and 12 months including: Manchester-Oxford Foot and Ankle Questionnaire (MOXFQ (foot and ankle)) and the EuroQol five-dimension five-level questionnaire (EQ-5D-5L). Radiological pre- and postoperative data included Kellgren-Lawrence score and implant position measurement. This was supplemented by data from the National Joint Registry through record linkage to determine: American Society of Anesthesiologists (ASA) grade at index procedure; indication for surgery, index ankle previous fracture; tibial hind foot alignment; additional surgery at the time of TAA; and implant type. Multivariate regression models assessed outcomes, and the relationship between MOXFQ and EQ-5D-5L outcomes, with patient characteristics.

Results

Data from 238 patients were analyzed. There were significant improvements in MOXFQ and EQ-5D-5L among people who underwent TAA at six- and 12-month assessments compared with preoperative scores (p < 0.001). Most improvement occurred between preoperative and six months, with little further improvement at 12 months. A greater improvement in MOXFQ outcome postoperatively was associated with older age and more advanced radiological signs of ankle osteoarthritis at baseline.

Conclusion

TAA significantly benefits patients with end-stage ankle disease. The lack of substantial further overall change between six and 12 months suggests that capturing PROMs at six months is sufficient to assess the success of the procedure. Older patients and those with advanced radiological disease had the greater gains. These outcome predictors can be used to counsel younger patients and those with earlier ankle disease on the expectations of TAA.

Early Radiographic and Clinical Outcomes of a Novel, Fixed-Bearing Fourth-Generation Total Ankle Replacement System

BACKGROUND

The Cadence Total Ankle System is a 2-component, fixed-bearing fourth-generation total ankle arthroplasty (TAA) system that was introduced for clinical use in 2016. The purpose of this study was to report non-inventor, non-industry funded survivorship, radiographic and clinical outcomes, and early complications following use of this implant at a minimum of 2 years.

METHODS

This single-center retrospective study included patients who underwent TAA by 2 surgeons with this novel fixed-bearing system between January 2017 and September 2018. Forty-eight patients were evaluated at an average of 33.6 months. Radiographic outcomes included preoperative and postoperative tibiotalar angle on anteroposterior radiographs of the ankle, sagittal tibial angle (STA) on lateral radiographs of the ankle, and periprosthetic lucency formation and location. Revision and reoperation data were collected, and patient-reported outcomes were assessed using Patient Reported Outcomes Measurement Information System (PROMIS). Subgroup analysis assessed associations between preoperative deformity, postoperative implant alignment, PROMIS scores, and periprosthetic lucency formation.

RESULTS

Survivorship of implant was 93.7%, with 3 revisions, 1 due to infection and 2 due to loosening of the implant (1 tibial and 1 talar component). Three patients had reoperations (6.3%): 2 for superficial infection and 1 for gutter debridement due to medial gutter impingement. Fifteen patients (35.8%) developed periprosthetic lucencies, all on the tibial side. PROMIS scores improved after surgery in all domains except Depression. Patients with significant postoperative periprosthetic lucency had worse postoperative PROMIS Physical function scores than patients without lucency (P < .05).

CONCLUSION

This study demonstrated excellent minimum 2-year clinical and radiographic outcomes and low revision and reoperation rates of this new fourth-generation TAA system. Future studies with longer follow-up, especially on patients with periprosthetic lucency, are necessary to investigate the long-term complications and understand the long-term functional and radiographic outcomes of this implant.

Patient-specific instrumentation in total ankle arthroplasty

The recent increase in the adoption of total ankle arthroplasty (TAA) reflects the improvements in implant designs and surgical techniques, including the use of preoperative navigation system and patient-specific instrumentation (PSI), such as custom-made cutting guides. Cutting guides are customized with respect to each patient's anatomy based on preoperative ankle computed tomography scans, and they drive the saw intra-operatively to improve the accuracy of bone resection and implant positioning. Despite some promising results, the main queries in the literature are whether PSI improves the reliability of achieving neutral ankle alignment and more accurate implant sizing, whether it is actually superior over standard techniques, and whether it is cost effective. Moreover, the advantages of PSI in clinical outcomes are still theoretical because the current literature does not allow to confirm its superiority. The purpose of this review article is therefore to assess the current literature on PSI in TAA with regard to current implants with PSI, templating and preoperative planning strategies, alignment and sizing, clinical outcomes, cost analysis, and comparison with standard techniques.

Outcomes and Complications of the INFINITY Total Ankle: A Systematic Review

IV.

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.

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.

Two-Year Outcomes After Total Ankle Replacement With a Novel Fixed-Bearing Implant

BACKGROUND

The Integra Cadence total ankle replacement (TAR) is a fourth-generation anatomic, fixed-bearing implant requiring minimal tibial and talar resection, which has been in clinical use since June 2016. The primary purpose of this study is to assess its short-term clinical and radiographic outcomes after TAR using this prosthesis.

METHODS

This is a prospective case series of consecutive patients that underwent TAR using this novel fourth-generation prosthesis between June 2016 and November 2017. The primary outcome of interest was the Ankle Osteoarthritis Scale (AOS). Secondary outcomes included Short Form Health Survey-36 (SF-36) scores, radiographic alignment, complications, reoperations, and revisions.

RESULTS

In total, 69 patients were included in our study. Fifty-one patients (73.9%) required a total of 91 ancillary procedures. Postoperatively, AOS pain scores decreased significantly by an average of 17.8±30.1 points from 45.9±18.2 to 28.4±27.3 (P < .001). AOS disability scores also decreased significantly following surgery by an average of 22.0±30.5 points from 53.9±18.5 to 32.5±27.9 (P < .001). The SF-36 physical component summary score improved 10.4±9.8 points from 33.1±9.1 to 42.6±9.1 (P < .001). Radiographic analysis demonstrated significant improvement to neutral coronal plane alignment, which was achieved in 97% of patients (P < .01) with no cyst formation at 2 years. There was 1 reported complication, 9 reoperations, and no metal or polyethylene component revisions. Overall, the 2-year implant survivorship was 100% in our cohort. Eighteen patients (26.1%) demonstrated fibrous ingrowth of the tibial component. However, outcome scores for these patients did not demonstrate any negative effects.

CONCLUSION

In our hands, this TAR system demonstrated excellent early clinical and radiographic outcomes. Patients reported improved physical health status, pain, and disability in the postoperative period. Total ankle instrumentation allowed for accurate and reproducible implantation with correction of coronal and sagittal plane deformities. Early results for the clinical use of this TAR system are promising, but further long-term prospective outcome studies are necessary.

LEVEL OF EVIDENCE

Level IV, case series.

Early experience and patient-reported outcomes of 503 INFINITY total ankle arthroplasties

AIMS

This is a multicentre, non-inventor, prospective observational study of 503 INFINITY fixed bearing total ankle arthroplasties (TAAs). We report our early experience, complications, and radiological and functional outcomes.

METHODS

Patients were recruited from 11 specialist centres between June 2016 and November 2019. Demographic, radiological, and functional outcome data (Ankle Osteoarthritis Scale, Manchester Oxford Questionnaire, and EuroQol five-dimension five-level score) were collected preoperatively, at six months, one year, and two years. The Canadian Orthopaedic Foot and Ankle Society (COFAS) grading system was used to stratify deformity. Early and late complications and reoperations were recorded as adverse events. Radiographs were assessed for lucencies, cysts, and/or subsidence.

RESULTS

In all, 500 patients reached six-month follow-up, 420 reached one-year follow-up, and 188 reached two-year follow-up. The mean age was 67.8 years (23.9 to 88.5). A total of 38 patients (7.5%) presented with inflammatory arthritis. A total of 101 (20.0%) of implantations used patient-specific instrumentation; 167 patients (33.1%) underwent an additional procedure at the time of surgery. A total of seven patients died of unrelated causes, two withdrew, and one was lost to follow-up. The mean follow-up was 16.2 months (6 to 36). There was a significant improvement from baseline across all functional outcome scores at six months, one, and two years. There was no significant difference in outcomes with the use of patient-specific instrumentation, type of arthritis, or COFAS type. Five (1.0%) implants were revised. The overall complication rate was 8.8%. The non-revision reoperation rate was 1.4%. The 30-day readmission rate was 1.2% and the one-year mortality 0.74%.

CONCLUSION

The early experience and complications reported in this study support the current use of the INFINITY TAA as a safe and effective implant in the treatment of end-stage ankle arthritis. Cite this article: Bone Joint J 2021;103-B(7):1270-1276.

Total ankle arthroplasty

AIMS

We report the medium-term outcomes of a consecutive series of 118 Zenith total ankle arthroplasties (TAAs) from a single, non-designer centre.

METHODS

Between December 2010 and May 2016, 118 consecutive Zenith prostheses were implanted in 114 patients. Demographic, clinical, and patient-reported outcome measures (PROMs) data were collected. The endpoint of the study was failure of the implant requiring revision of one or all of the components. Kaplan-Meier survival curves were generated with 95% confidence intervals (CIs) and the rate of failure calculated for each year.

RESULTS

Eight patients (ten ankles) died during follow-up, but none required revision. Of the surviving 106 patients (108 ankles: rheumatoid arthritis (RA), n = 15; osteoarthritis (OA), n = 93), 38 were women and 68 were men, with a mean age of 68.2 years (48 to 86) at the time of surgery. Mean follow-up was 5.1 years (2.1 to 9.0). A total of ten implants failed (8.5%), thus requiring revision. The implant survival at seven years, using revision as an endpoint, was 88.2% (95% CI 100% to 72.9%). There was a mean improvement in Manchester-Oxford Foot and Ankle Questionnaire (MOXFQ) from 85.0 to 32.8 and visual analogue scale (VAS) scores from 7.0 to 3.2, and overall satisfaction was 89%. The three commonest complications were malleolar fracture (14.4%, n = 17), wound healing (13.6%, n = 16), and superficial infection (12.7%, n = 15). The commonest reason for revision was aseptic loosening. No patients in our study were revised for deep infection.

CONCLUSION

Our results show that Zenith survival rates are comparable with those in the literature for other implants and in the National Joint Registry (NJR). Overall patient satisfaction was high as were functional outcomes. However, the data highlight potential complications associated with this surgery. The authors believe that these figures support ankle arthroplasty as an option in the treatment of ankle arthritis. Cite this article: Bone Joint J 2021;103-B(4):696-703.

Infinity ankle arthroplasty with traditional instrumentation and PSI prophecy system: preliminary results

Ankle arthrodesis has been considered the surgical Gold Standard for advanced ankle arthritis; prosthetic replacement of the tibio-talar joint played a secondary role.The introduction of last generation ankle prostheses lead to better outcome and a lower rate of complication. PSI represents the most recent innovations introduced on the market of ankle arthroplasty:PSI is proposed as a surgical technique capable of making ankle arthroplasty more accurate and more reproducible compared to standard referencing guides Aim of the study is to report early clinical and radiographic outcomes obtained from a single surgeon experience by implanting the same ankle prosthesis using a standard (STD) or a PSI instrumentation Unlike no difference in the average increment of normalized sub score related to function in each group (PSI vs STD), the analysis of normalized pain sub score pointed out a greater average improvement in the PSI group(+75%)compared to the STD group(+62%);this result has been adovacated to the absence of post operative gutter impingement syndrome in the PSI group compared to the STD referencing group. The analysis of radiographic angles revealed a more accurate and reproducible positioning of the components in the PSI group; ankle arthroplasty performed with PSI reported a reduction of both surgical times and the need of intraop.fluoroscopy. PSI ankle arthroplasty achived more accurate and reproducible clinical and radiographic results compared to STD instrumentation;long-term follow-up are needed to demonstrate whether a better positioning of the implant is associated with an increased survival of the prosthesis and therefore justifies the additional costs of PSI.

Outcomes Following Total Ankle Arthroplasty: A Review of the Registry Data and Current Literature

End-stage ankle arthritis has a significant effect on function and quality of life. Total ankle arthroplasty continues to emerge as a safe and effective treatment of ankle arthritis. Ankle arthroplasty preserves motion at the ankle joint, while still achieving the primary goal of pain relief. With encouraging outcomes and improved implant longevity, there has been significant improvement on the results of first-generation implants. Further high-quality studies are required to clarify outcomes post ankle arthroplasty. This article reviews the latest data from national registries and the wider literature to evaluate the current status with outcomes of modern total ankle replacements.