Total ankle replacement in rheumatoid arthritis

Ten-Year Follow-Up of a Customized Total Talar Prosthesis for Revision Total Ankle Arthroplasty: A Case Report

CASE

A 74-year-old woman with rheumatoid arthritis had undergone total ankle arthroplasty (TAA) for severe ankle joint destruction at our hospital 14 years earlier. Radiographs of the ankle revealed displacement of the tibial component and subsidence of the talar component. Revision TAA was performed using a customized alumina ceramic total talar prosthesis.

CONCLUSION

The 10-year outcome of revision TAA with a total talar prosthesis was satisfactory, with no postoperative complications, such as displacement of the tibial component, dislocation of alumina ceramic artificial talus, or progression of degenerative changes in the talonavicular and subtalar joints.

Ten-year revision rates of contemporary total ankle arthroplasties equal 22%. A meta-analysis

BACKGROUND

The National Institute for Health and Care Excellence criterion for hip replacements is a (projected) revision rate of less than 5% after 10 years. No such criterion is available for ankle prostheses. The objective of the current study is to compare survival rates of contemporary primary ankle prostheses to the hip-benchmark.

METHODS

The PRISMA methodology was used. Eligible for inclusion were clinical studies reporting revision rates of currently available primary total ankle prostheses. Data was extracted using preconstructed forms. The total and prosthesis-specific annual revision rate was calculated.

RESULTS

Fifty-seven articles of eight different ankle prostheses were included (n = 5371), totaling 513 revisions at an average 4.6 years of follow-up. An annual revision rate of 2.2 was found (i.e. an expected revision rate of 22% at 10 years).

CONCLUSIONS

The expected 10-year revision rate of contemporary ankle prostheses is lower than the current benchmark for hip prostheses.

Radiographic Outcomes of Mobile-Bearing Total Ankle Arthroplasty for Patients With Rheumatoid Arthritis

BACKGROUND

Ankle disorders in patients with rheumatoid arthritis (RA) reduce their quality of life and activities of daily living. The aim of this study was to evaluate the midterm clinical and radiographic outcomes of TAA in patients with RA.

METHODS

This retrospective study included patients with a minimum follow-up of 2 years. A total of 37 RA patients (39 ankles) were enrolled in this study from August 2006 to March 2016. All the patients had undergone primary cemented mobile-bearing total ankle arthroplasty (TAA). Nine ankles received arthrodesis of the subtalar joint simultaneously. Patient-reported outcomes were measured preoperatively and at the latest follow-up by Self-Administered Foot-Evaluation Questionnaire (SAFE-Q). Radiographs of the ankle were analyzed preoperatively and at all follow-up visits to measure the periprosthetic radiolucent line, migration of the tibial component, and the subsidence of the talar component. Intraoperative and postoperative complications were recorded. The average duration of follow-up for the entire cohort was 5.0 ± 2.0 years (range 2.1-10.1 years).

RESULTS

All subscales of the SAFE-Q had improved significantly at the latest follow-up. No significant difference was found between the range of motion of the ankle before and after the surgery. Radiolucent lines were observed in 28 (73.7%) ankles. Migration of the tibial component and subsidence of the talar component were found in 8 (21.1%) and 11 (28.9%) ankles, respectively. Intraoperative malleolus fractures occurred in 3 (7.7%) ankles and delayed wound healing in 10 (25.6%) ankles. Four ankles were removed because of deep infection or noninfective loosening, resulting in an implant survival rate of 88.4% (95% CI, 0.76-1.0) at 10 years.

CONCLUSION

The midterm patient-reported outcomes and implant retention rate after cemented mobile-bearing TAA for RA patients were satisfactory. However, a low radiographic implant success rate was observed.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Early Functional, Radiological Outcomes and Satisfaction Rates of Total Ankle Arthroplasty in an Asian Population

BACKGROUND

Few studies have outlined the outcomes and complications in Asians undergoing total ankle arthroplasty. This study reports the functional, radiological outcomes and satisfaction rates in our Asian population.

METHODS

Patients who underwent primary total ankle arthroplasty from 2007 to 2013 were recruited. Outcomes evaluated were the AOFAS Ankle-Hindfoot Score (AHS), Visual Analogue Scale (VAS), and the Short Form 36 (SF-36)questionnaire. Outcome scores were collected prospectively up to 2 years. Patient satisfaction was evaluated on a 6-point scale based on North American Spine Society Low Back Pain Instrument and classified as satisfied or unsatisfied.

RESULTS

Forty-one patients underwent primary total ankle arthroplasty. All patients experienced improvements in AHS, VAS, and Mental Component Summary score of the SF-36 at both 6-month and 2-year postoperative interval. The mean AHS score improved from 35 ± 19 points preoperatively to 64 ± 24 at 6 months (P<.001) and 72 ± 26 at 24 months (P <.001). VAS scores improved from 7 ± 2 preoperatively to 3 ± 3 (P < .001) at 6 and 24 months. The Physical Component Summary (PCS) of the SF-36 has an established minimum clinically important difference (MCID) of 5. The mean improvement in PCS in our cohort met this MCID for the PCS; 63% and 71% of patients were satisfied with the procedure at 6 months and 2 years postoperatively, respectively. Revision rate in this series was 9.7%.

CONCLUSION

Total ankle arthroplasty has good patient satisfaction rates, with favorable early clinical outcome in Asian patients.

LEVELS OF EVIDENCE

Therapeutic, Level II.

Ankle arthroplasty: A review and summary of results from joint registries and recent studies

Total ankle arthroplasty offers a reasonable alternative to ankle arthrodesis in carefully selected patients.

It is debatable whether rheumatoid arthritis patients have better outcomes compared with those who have ankle arthroplasty for either primary osteoarthritis or post-traumatic arthritis.

Aseptic loosening and infection are the most common complications requiring revision.

It is worth noting that some of the best survival rates are seen in the surgeon-designer case series.

The uncemented mobile or fixed bearing prostheses have better outcomes compared with their older counterparts.

There is no convincing evidence to suggest superiority of one design over another among the currently available prostheses.

Ankle arthroplasty surgery has a steep learning curve; the prosthesis choice should be driven by the surgeon’s training and experience.

Cite this article: EFORT Open Rev 2018;3:391-397. DOI: 10.1302/2058-5241.3.170029

Total Ankle Arthroplasty for Rheumatoid Arthritis in Japanese Patients: A Retrospective Study of Intermediate to Long-Term Follow-up

Background:

Outcomes after total ankle arthroplasty (TAA) combined with additive techniques (augmentation of bone strength, control of soft-tissue balance, adjustment of the loading axis) for the treatment of rheumatoid arthritis were evaluated after intermediate to long-term follow-up. The influences of biologic treatment on the outcomes after TAA were also evaluated.

Methods:

We performed a retrospective observational study involving 50 ankles (44 patients) that underwent TAA for the treatment of rheumatoid arthritis. The mean duration of follow-up was 7.1 years. Clinical outcomes were evaluated with use of the Japanese Society for Surgery of the Foot (JSSF) scale score and a postoperative self-administered foot-evaluation questionnaire (SAFE-Q). Radiographic findings were evaluated as well. These parameters also were compared between patients managed with and without biologic treatment.

Results:

This procedure significantly improved the clinical scores of the JSSF rheumatoid arthritis foot and ankle scale (p < 0.0001). Forty-eight of the 50 ankles had no revision TAA surgery. Subsidence of the talar component was seen in 8 ankles (6 in the biologic treatment group and 2 in the non-biologic treatment group); 2 of these ankles (both in the biologic treatment group) underwent revision TAA. The social functioning score of the SAFE-Q scale at the time of the latest follow-up was significantly higher in the biologic treatment group (p = 0.0079). The dosage of prednisolone (p = 0.0003), rate of usage of prednisolone (p = 0.0001), and disease-activity score (p < 0.01) at the time of the latest follow-up were all significantly lower in the biologic treatment group.

Conclusions:

TAA is recommended for the treatment of rheumatoid arthritis if disease control, augmentation of bone strength, control of soft-tissue balance, and adjustment of the loading axis are taken into account. The prevention of talar component subsidence remains a challenge in patients with the combination of subtalar fusion, rheumatoid arthritis, and higher social activity levels.

Level of Evidence:

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

Total ankle replacement

BACKGROUND

About 1% of adults suffer from painful osteoarthritis of the ankle. The current literature contains no information on the percentage of such patients who derive long-term relief of symptoms from conservative treatment. Advanced ankle osteoarthritis can be treated with non-joint-preserving measures, such as total ankle replacement and ankle fusion.

METHODS

This review is based on selected relevant publications, guidelines from Germany and abroad, and the authors' personal experience.

RESULTS

Before surgery is considered, conservative measures such as physiotherapy and orthopedic aids should be used to the fullest possible extent. No randomized trials have yet been published comparing total ankle replacement with ankle fusion. Total ankle replacement with newer types of prosthesis yields good to very good intermediate-term and long-term results, with mean success rates of up to 90% at 10 years (range, 68-100%). Independent risk factors for the failure of ankle replacement are age over 70 years (odds ratio [OR] 3.84), primary osteoarthritis (OR 7.19), post-traumatic osteoarthritis (OR 6.2), and type of prosthesis (e.g., single hydroxyapatite coating: OR 15.04). The average range of motion of the replaced ankle joint is 25° to 30°, with values as high as 60°.

CONCLUSION

Total ankle replacement is a good treatment option for complete, end-stage ankle arthritis. It can restore joint function and make the patient mobile with little or no pain. There are, however, many contraindications to be taken into account. There is a need for further studies of the biomechanics of arthritic and replaced ankle joints and for long-term follow-up studies of total ankle replacement.

Wear characteristics of WSU total ankle replacement devices under shear and torsion loads

BACKGROUND

There are several factors that contribute to the failure of total ankle replacement (TAR). Aseptic loosening is one of the primary mechanisms of failure in TAR. Since a cross-linked ultrahigh molecular weight polyethylene (UHMWPE) is used as liner material, there is a need to quantify and develop methods to estimate the wear rates of the liners. High contact stresses develop during the gait generates wear debris resulting in osteolysis and early loosening of the prostheses.

METHODS

In this paper wear characteristics of Wright State University (WSU) TARs were determined by applying shear and torsion loads. Viscoelastic properties were used to model the liner component. Finite element analysis was conducted to determine the wear rate by deriving Von Mises and contact stresses generated in the liner and wear rate equation was used to predict the wear rate.

RESULTS

Titanium alloy has shown less resistance towards shear forces when compared with other metal alloys. Under torsion, rotation angle plays a significant role in affecting the peak stress values. The maximum average contact stress was 14.46 MPa under torsion load which contributes to a wear rate of 0.67 (mm(3)/year) for one of the mobile bearing models. The maximum average contact stress and wear rate obtained from the analytical study were 10.55 MPa and 0.33 (mm(3)/year), respectively for mobile bearing models. When compared with mobile bearing model, fixed bearing model has shown higher stresses at different degrees of rotation.

CONCLUSION

Both shear and torsion loads cause significantly lower contact stresses and wear when compared to the axial load. Further studies are necessary to accurately determine the wear behavior of fixed bearing TAR models.

A systematic review of intermediate-term outcomes and failure rates for total ankle replacements: an Asian perspective

BACKGROUND

There are few records for total ankle replacement (TAR) in Asia. We aimed to report the cumulative intermediate-term outcomes in terms of clinical scores, survivorship and failure rates for patients managed with TAR in Asia.

METHODS

We conducted a systematic search for relevant articles published in English and other languages between January 1990 and February 2012. The study published before 1990 and used outdated prosthesis designs implanted before the early 1980s was excluded. Eligible studies were evaluated using the Coleman Methodology Score and data collection was independently performed by three reviewers.

RESULTS

Seven studies qualified for analysis, describing 321 implants (112 HINTEGRA(®), 104 TNK, 35 STAR, 13 ND-Bioceram, 57 un-reported implants). Overall studies showed the improvement of clinical scores following TAR. Pooled data for the survivorship analysis ranged from 100% at 3.2 years to 77% at 14.1 years. Pooled mean failure rate was 4.9±3.2% over a mean follow-up of 5.2±1.7 years.

CONCLUSIONS

TAR prostheses currently used in Asia achieved satisfactory intermediate-term outcomes in terms of clinical scores, survivorship and failure rates.

Three-dimensional morphometric study of the trapezium shape of the trochlea tali

The trapezium shape of the talar dome limits the use of 2-dimensional plain radiography for morphometric assessment because only 2 of the 4 required parameters can be measured. We used computed tomography data to measure the 4 morphologic parameters of the trochlea tali: anterior width, posterior width, trochlea tali length, and angle of trapezium shape. A total of 99 subjects underwent computed tomography scanning, and the left and right talus bones were both virtually modeled in 3 dimensions. The 4 morphologic parameters were measured 3 times each to obtain the intraclass correlation, and analysis of variance was used to check for any significant differences between the repeated measurements. The average intraclass correlation coefficient for the measurements for 2 to 3 trials was 0.94 ± 0.04. Statistical analyses were performed on the data from all 198 talus bones using SAS software, comparing male and female and left and right bones. All 4 morphometric values were greater in the male group. No significant differences were found between the left and right talus bones. A strong positive correlation was observed between the trochlea tali length and the anterior width. The angle of trapezium shape showed no correlation with the other 3 parameters. The measurements were compared with the dimensions of the current talar components of 4 total ankle arthroplasty implants. However, most of them did not perfectly match the trapezium shape of the talus from our population. We successfully analyzed the trapezium shape of the trochlea tali using reliable virtual 3-dimensional measurements. Compared with other published reports, our study showed a relatively smaller dimension of the trochlea tali than the European counterparts.

History of total ankle replacement

Attempts at ankle replacement have existed for at least 50 years. Time has essentially eliminated constrained, cemented, first-generation ankle replacements. Although some two-component, more anatomic, designs are still used with varying success, three-component "mobile bearing" ankle prostheses are winning the race of evolution. Not only have implants change over the years, but also the patients and surgeons. Surgeons specialize, improving their surgical outcomes and expanding the indications for total ankle replacement in technically demanding complex ankles. High-demand, younger patients, but also obese ones, are potential candidates for a total ankle replacement. This article provides a review of the history of total ankle replacement.

Mobile- and fixed-bearing total ankle prostheses: is there really a difference?

Approximately 1% of the world's adult population is affected by ankle osteoarthritis (OA). Therapeutic options include conservative and surgical measures. Because of substantial progress in total ankle replacement, ankle fusion is no longer the "gold standard" therapy for end-stage ankle OA. Various ankle prostheses have been designed and are currently available. This article reviews the in vitro studies addressing the biomechanics and kinematics of the replaced ankle. Furthermore, a systematic literature review was conducted to assess possible differences in clinical outcomes, including prosthesis survivorship and postoperative range of motion between mobile- and fixed-bearing total ankle prostheses.

Total ankle arthroplasty versus ankle arthrodesis. Comparison of sports, recreational activities and functional outcome

PURPOSE

Ankle arthrodesis (AAD) and total ankle replacement (TAR) are the major surgical treatment options for severe ankle arthritis. There is an ongoing discussion in the orthopaedic community whether ankle arthrodesis or ankle fusion should be the treatment of choice for end stage osteoarthritis. The purpose of this study was to compare the participation in sports and recreational activities in patients who underwent either AAD or TAR for end-stage osteoarthritis of the ankle.

METHODS

A total of 41 patients (21 ankle arthrodesis /20 TAR) were examined at 34.5 (SD18.0) months after surgery. At follow-up, pre- and postoperative participation in sports and recreational activities has been assessed. Activity levels were determined using the ankle activity score according to Halasi et al. and the University of California at Los Angeles (UCLA) activity scale. Clinical and functional outcome was assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score. The percentage of patients participating in sports and recreational activities, UCLA score and AOFAS score were compared between both treatment groups.

RESULTS

In the AAD group 86% were active in sports preoperatively and in the TAR group this number was 76%. Postoperatively in both groups 76% were active in sports (AAD, p = 0.08). The UCLA score was 7.0 (± 1.9) in the AAD group and 6.8 (± 1.8) in the TAR group (p = 0.78). The AOFAS score reached 75.6 (± 14) in the AAD group and 75.6 (± 16) in the TAR group (p = 0.97). The ankle activity score decrease was statistically significant for both groups (p = 0.047).

CONCLUSIONS

Our study revealed no significant difference between the groups concerning activity levels, participation in sports activities, UCLA and AOFAS score. After AAD the number of patients participating in sports decreased. However, this change was not statistically significant.

Results of total ankle arthroplasty

Most published reports related to total ankle arthroplasty have a fair to poor-quality level of evidence. Comparative studies with a fair to good-quality level of evidence suggest that total ankle arthroplasty provides equal pain relief and possibly improved function compared with ankle arthrodesis. On the basis of the current literature, survivorship of total ankle arthroplasty implants, when measured as the retention of metal components, ranges from 70% to 98% at three to six years and from 80% to 95% at eight to twelve years. Several investigators have argued that, in the evolution of total ankle arthroplasty, some obligatory reoperation without removal of the metal implants is anticipated; examples of reoperation include relief of osseous or soft-tissue impingement, improvement of alignment or stability of the foot and ankle, bone-grafting for cystic lesions, and/or polyethylene exchange. A successful return to low-impact, recreational sporting activities is possible after total ankle arthroplasty.

Measuring foot and ankle injury outcomes: common scales and checklists

Functional health outcome measures are increasingly being used in both clinica trials and practice as measures of patient health. Whilst outcome measures can be generic, there are a number of foot and ankle specific measures available and in use. These are being used as not only region specific but also disease specific measures of patient function. Unfortunately not all of these outcome measures have been completely validated which leads to challenges in applying the results of outcomes research to specific patients. Continued work however is being done in this area and these challenges provide opportunities for further investigation into the role of functional outcome scores specific to the foot and ankle.

Comparison of different outcome instruments following foot and ankle trauma

BACKGROUND

Identifying optimal treatment strategies in patients with traumatic foot and ankle injuries has been hampered by the use of multiple available outcome measures with unproven reliability and validity. This prospective observational study aimed to measure the correlation between six functional outcome measures in patients with traumatic foot and ankle injuries.

MATERIALS AND METHODS

Patients 18 years of age or older with a traumatic foot or ankle injury completed the Short Form-12 (SF-12), Short Musculoskeletal Functional Assessment (SMFA), Foot Function Index (FFI), Foot and Ankle Ability Measure (FAAM), American Academy of Orthopedic Surgeons (AAOS), Foot and Ankle Questionnaire and American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale at a single followup visit. Raw scores for each of the outcome measures were calculated. Fifty-two patients were enrolled in our study. Pearson correlation coefficients provided measures of correlation.

RESULTS

Moderate to strong correlations were found for most pairwise comparisons of raw scores and functional categorical rankings (ρ=|0.5243 to 0.92|, p < 0.002). The strongest correlations were found between the SMFA, FFI, FAAM and AAOS Foot and Ankle Questionnaire.

CONCLUSION

High correlations between scores on six commonly used functional outcome instruments suggest it is likely unnecessary to use more than one instrument when examining functional outcome in patients with traumatic foot and ankle injuries. However, inconsistencies between measures in the same patient population suggest a need for further validation and scrutiny.

Total ankle arthroplasty in the rheumatoid patient

Total ankle replacement in the rheumatoid patient is a feasible and effective treatment for ankle arthritis. The benefits of ankle prosthesis are good pain relief, acceptable function, and patient satisfaction. It is a joint-sparing procedure for restoring functionality. All investigators of total ankle replacement feel that, as clinicians gain experience with the procedure and related products, difficulties and risks associated with the procedure will decline. Following an early history of failure and poor patient satisfaction, more recent results have shown promise.

Total ankle prostheses in rheumatoid arthropathy: Outcome in 52 patients followed for 1-9 years

BACKGROUND AND PURPOSE

The first generations of total ankle replacements (TARs) showed a high rate of early failure. In the last decades, much progress has been made in the development of TARs, with the newer generation showing better results. We evaluated TARs implanted with rheumatoid arthritis (RA) or juvenile inflammatory arthritis (JIA) as indication.

PATIENTS AND METHODS

58 total ankle prostheses (Buechel-Pappas and STAR type) were implanted in patients with RA (n = 53) or JIA (n = 5) in 54 patients (4 bilateral). After a mean followup of 2.7 (1-9) years, all patients were reviewed by two orthopedic surgeons who were not the surgeons who performed the operation. Standard AP and lateral radiographs were taken and a Kofoed ankle score was obtained; this is a clinical score ranging from 0-100 and consists of sub-scores for pain, disability, and range of motion.

RESULTS

2 patients died of unrelated causes. Of the 52 patients who were alive (56 prostheses), 51 implants were still in place and showed no signs of loosening on the most recent radiographs. The mean Kofoed score at follow-up was 73 points (SD 16, range 21-92). 4 patients showed a poor result (score < 50) with persistent pain for which no obvious reason could be found. 5 implants were removed, 4 because of infection and 1 because of aseptic loosening.

INTERPRETATION

Medium-term results of the STAR and BP types of TAR in RA were satisfactory. The main reason for failure of the implant was infection.

History and evolution in total ankle arthroplasty

INTRODUCTION

The current study provides an overview of history and evolution in total ankle arthroplasty.

METHODS

We conducted a comprehensive literature search without limitations to language. Information from any source, providing evidence of the use ankle of prostheses (e.g. biomechanical testing, cadaveric implantations or clinical use) was evaluated. Data regarding biomechanical concepts, design considerations, published results (patient numbers, surgical method, follow-up, complications and survival rates) were collected.

RESULTS

Only level IV studies were found. Mobile-bearing prostheses are mainly used in Europe, and fixed-bearing implants are mainly used in the USA. The current designs' failure rate is 10-12% at approximately 5 years. Survival rates vary among different institutions. Increased surgeons' experience is associated with better outcomes.

DISCUSSION

Biomechanical studies and review of previous implant failures has led to the development of a new generation of implants.

CONCLUSIONS

Results show that ankle arthroplasty is a viable alternative for the management of ankle arthritis in selected patients.

Osteoarthritis of the ankle: the role of arthroplasty

Total ankle arthroplasty was developed to reduce pain and retain motion of the ankle joint in patients with osteoarthritis. The ankle joint has unique, complex anatomic and biomechanical characteristics that must be considered in a successful total ankle arthroplasty prosthesis. Initial designs from the 1960s to the 1970s had many failures. Current designs use two or three components, and recent reports on total ankle arthroplasty show consistent good to excellent intermediate clinical results, with up to 90% decreased pain and high patient satisfaction. The follow-up time of these studies is limited, however, and long-term studies with 10- to 15-year follow-ups are needed. Also, a wide variety of complications has been reported, including osteomyelitis and osteolysis. To limit the number of complications and improve clinical outcome of total ankle arthroplasty, careful patient selection and surgeon experience are important.

Moderne 3-Komponenten-Sprunggelenkprothesen

Luxation and excessive wear of the mobile bearing in modern three-piece total ankle replacement (TAR) is reported. We conducted a systematic review of studies to explore and discuss the rate and causes of these complications.A systematic review of studies since 2000 showed 26 studies with altogether 1,318 followed up TARs which we analyzed. Of these 1,318 TARs, 188 (14.3%) were revised and 56 (4.2%) complications with the mobile bearing were reported. A total of 39 cases (3%), i.e., 20.7% of all revisions, were revised due to failure of the mobile bearing, including 17 cases with subluxation (1.3%), 15 with asymmetric load of the bearing (1.1%), 10 with fracture of the polyethylene (PE) inlay (0.76%), 7 with massive PE wear (0.53%), and 7 with luxation of the meniscal bearing (0.53%).Complications due to the meniscal mobile bearing in TARs such as luxation, subluxation, massive wear, and fracture of the PE inlay are rare complications. The cause of these complications is regularly not found in the design of this three-piece total ankle replacement. Causes of failure of the mobile bearing are mostly found in incorrect indication, incorrect soft tissue balancing, incorrect positioning of components, implantation in ankles with hindfoot malalignment and ankle instability.

Total ankle replacement for rheumatoid ankle arthritis

This article reviews total ankle replacement for rheumatoid ankle arthritis. The benefits of preserving the mobility of the ankle joint for the patient who has rheumatoid arthritis are undisputed. Recent reports have consistently shown that patient satisfaction following ankle replacement is high and prosthetic survival is more than 90% at five years and in many instances more than 80% at 10 years. Ankle replacement is contraindicated when there is severe coronal plane deformity.

Outcome analysis of agility total ankle replacement with prior adjunctive procedures: two to six year followup

BACKGROUND

A retrospective case review of 65 agility total ankle replacements (64 patients) was done between April, 1998, and March, 2002. The purpose of this study was to more closely identify factors that may be predictive of a favorable outcome, including a comparison of outcome measures between patients who had preoperative corrective procedures and those patients who did not.

METHODS

The outcomes of this series of patients were examined with post-operative Short Form (SF)-36 scores as well as chart and radiographic review. Endpoints for this study were amputation, arthrodesis, osteochondral allograft, total ankle revision, or revision of either or both components. The Kaplan-Meier survivorship curve also was estimated including the 95% confidence intervals.

RESULTS

Patients with rheumatoid arthritis (RA) were found to have a statistically significant lower rate of failure. Use of a size 1 prosthesis was associated with subsidence and the highest rate of subsequent failure, but fell short of statistical significance (because of the limited power of the study). Smoking, diabetes, and methotrexate use were not associated with an adverse outcome either clinically or statistically, but the number of patients in each group was small. The age of the patient was not a factor in predicting failure of the prosthesis in the posttraumatic arthritis group; however it trended toward significance in the osteoarthritis group. The mean time to failure in patients with osteoarthritis was shorter than in the patients with post-traumatic arthritis but fell just short of statistical significance.

CONCLUSIONS

From this series we concluded that rheumatoid arthritis and use of a prosthesis larger than size 1 are predictive factors for better outcome.

Medial impingement after ankle replacement

Ankle replacements appear to offer a good alternative to fusion for most arthritic conditions. Use of mobile bearings has significantly improved results of ankle replacement. Ankle replacements still have a significant minor-complication rate which does not seem to affect the long-term outcome. Medial impingement as a complication has been reported with popular designs. We reviewed the senior author's first five years of Buechel-Pappas ankle replacements looking at AOFAS scores, VAS scores, patient satisfaction, learning curve of the surgeon and complications. Eight patients out of a total of 34 reported symptoms of medial impingement at follow-up. Four patients underwent revision surgery for this. Ankle replacements have a significant proportion of minor complications, one of which is medial impingement. Whether this is due to implant design, residual arthritis in medial recess or soft-tissue pathology is uncertain but revision surgery may be required.

Medial impingement after ankle replacement

Ankle replacements appear to offer a good alternative to fusion for most arthritic conditions. Use of mobile bearings has significantly improved results of ankle replacement. Ankle replacements still have a significant minor-complication rate which does not seem to affect the long-term outcome. Medial impingement as a complication has been reported with popular designs. We reviewed the senior author's first five years of Buechel-Pappas ankle replacements looking at AOFAS scores, VAS scores, patient satisfaction, learning curve of the surgeon and complications. Eight patients out of a total of 34 reported symptoms of medial impingement at follow-up. Four patients underwent revision surgery for this. Ankle replacements have a significant proportion of minor complications, one of which is medial impingement. Whether this is due to implant design, residual arthritis in medial recess or soft-tissue pathology is uncertain but revision surgery may be required.

The feasibility of total ankle prosthesis for severe arthropathy in haemophilia and prothrombin deficiency

The standard treatment for end-stage arthropathy of the ankle joint in haemophilia has been fusion of the ankle joint. Total ankle replacement is used in osteoarthritis and especially in rheumatoid arthritis with good medium-term results. In this case series three patients are being described, in which a total of five total ankle replacements have been preformed. After a median follow up of 4.3 years (range 1-8.7) all prostheses were still in place and did not show any signs of loosening. Clinical scores showed a good to excellent result. In this small series total ankle replacement in patients with bleeding disorders show promising results. Further studies are needed to show the value of this relatively new type of surgery in haemophilic patients.