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Komplikationen nach Sprunggelenkendoprothetik
Abstract
After the first attempts of total ankle arthroplasty about 1970 and the initially extremely high failure rate of up to 72% revisions or fusions, fusion was for many years the first choice in symptomatic end stage arthritis of the ankle joint. End of the eighties of the last century new designed implants were developed with a more anatomic design and the clinical short to midterm results became better [5,17,37]. Meanwhile total ankle arthroplasty is in a broad clinical use and has lost its experimental character. But the question, which choice is the better option (fusion or implant) is still in debate. An overview of the literature and the results of 456 personally performed procedures with detailed results of the first 125 AAA™ prosthesis are the basis for the discussion of the most important complications and pitfalls of this procedure. Personal recommendations for avoiding complications are added.
... Abb. 2). Orthner [9] fand in der Literatur eine Häufigkeit von 6-28,7%. Die Fraktur ereignet sich bei der Präparation der distalen Tibia, wenn der Sägeschnitt zur Resektion der distalen Tibiagelenkfläche zu weit medial angelegt wird und/oder weil oszillierende Sägen mit zu langen Sägeblättern (und entsprechendem Ausschlag zur Seite) verwendet werden. ...
... Ziel jeder Endoprothetik sind der Erhalt oder die Verbesserung der Gelenkbeweg-lichkeit. Zahlreiche Metaanalysen (Zitat bei [9]) ergaben, dass der Bewegungsgewinn nach OSG-Prothesenimplantation bei posttraumatischer Arthrose gering ist, durchschnittlich kann nur eine Verbesserung von insgesamt 5° in Plantarflexion und Dorsalextension erwartet werden. Das bedeutet für das Aufklärungsgespräch vor dem Eingriff, dass sich der Patient bei ausgeprägter Gelenksteife bewusst sein muss, dass eine Zunahme der Beweglichkeit nicht eintreten wird und die Operation vorrangig nur der Schmerzreduktion dienen kann (was mit der Arthrodese besser und nachhaltiger gelingt). ...
... Ob die von Orthner [9] ...
Athrosis of the ankle joint can lead to permanent stress pain, limitations in movement and gait disorders. The ultimate therapeutic options are arthrodesis or prosthesis implantation. For the latter option the following questions are of interest to patients: how often are ankle prostheses implanted? What are the alternatives? What risks are involved in the operation and what must be paid attention to? What is possible with prostheses and what is not? How many times must the operation be repeated? How long are prostheses fully operational and what happens if they loosen? How much reduction in the ability to work is to be expected? The best prerequisites for an ankle prosthesis after post-traumatic arthrosis are present in older (>55 years), female and less physically active patients. If a prosthesis is a viable option, later revision interventions and a long-lasting rehabilitation must be expected as well as the potential necessity of a secondary prosthesis.
Total ankle replacement (TAR) has become an increasingly performed surgical procedure in recent years and provides an alternative to the long-standing gold-standard of arthrodesis for treatment of ankle arthritis. Complications of TAR are still known. The major complications associated with failure of TAR are loosening of the components and insufficient wound repair. Due to the finding of periprosthetic cysts (PPC) in the Follow up we evaluated 141 primary cementless S.T.A.R.-TARs postoperatively, which were performed between October 2001 and November 2009. We analyzed all patients with a radiological Follow up of at least 24 months (n = 100). The mean Follow up period was 50 months. A total of 43 of 100 patients (43%) showed radiological signs of cystic formation. PPC were located 26 times in the Talus, 17 times in the Tibia and twice in the Fibula. 6 patients (6%) underwent surgical revision because of enlargement of the cyst and/or pain. This group of 43 patients had a mean range of motion of 32,5°. The mean AOFAS hindfoot score was 85,3 points. The group of patients without PPC had a mean range of motion of 28,5° and a mean AOFAS hindfoot score of 74 points. Thus patients with PPC had a statistical significant higher mean range of motion and a statistical significant higher mean AOFAS-score. There was no component loosening, polyethylene wear debris was not detectable macroscopically and in histopathological examination. The results and the clinical-prognostic value of PPC are discussed in the context with the current literature.
Wound breakdown of the operative incision is commonly encountered as a complication following ankle replacement surgery. Healing problems can progress to full thickness necrosis of the skin and deeper tissues jeopardizing the ultimate retention of the implants leading to compromised patient outcomes.
The medical records of 57 consecutive primary total ankle arthroplasties (TAA) were retrospectively reviewed after observing a higher than expected rate of wound-healing problems consistently involving the central third of the operative incision.
The rate of wound breakdown was 28% in this series. Analysis of various possible risk factors showed a statistically significant increase in rate of wound breakdown associated with smoking greater than 12 pack years, peripheral vascular disease, and cardiovascular disease.
Preoperative identification of patient risk factors associated with breakdown of the operative incision after TAA should improve outcome of the procedure. Screening of those patients with risk factors for wound breakdown is recommended prior to total ankle arthroplasty.
AES mobile-bearing total ankle replacement is evolved from the Buechel Pappas model. We report medium-term results of a prospective study with AES.
All patients who underwent AES TAR for ankle arthritis, by a single surgeon, from 2003 to 2006 were included, excluding neurologic disease, talar osteonecrosis and malalignment more than 20 degrees. All were reviewed at 6 months, 1 year, and at yearly intervals thereafter. X-rays were analyzed by three observers, using a 10-zone protocol. Fifty consecutive AES implants in 47 patients (mean age, 56 years; range, 21 to 79 year) were included, with at least 2 years' followup (mean 40 months). Preoperative diagnosis was mainly post-traumatic (50%) and osteoarthritis secondary to instability (36%). Associated procedures were performed in 38%.
Eighty-two percent had good functional results. The mean AOFAS score rose from 36.9 +/- 1.7 preoperatively to 85.4 +/- 12, dorsiflexion from 3 degrees to 7.3 degrees, and plantarflexion from 30.8 degrees to 37.8 degrees. Two ankles underwent secondary arthrodesis for talar subsidence and mechanical dislocation. Ninety-eight percent of implants were well positioned at 90 degrees +/-4. Mean prosthesis ROM on X-ray was 22.1 degrees. There were tibia/implant interface cysts (greater than 5 mm) in 62% of cases, and talar/implant interface cysts in 43%.
Although functional outcomes were comparable to the other mobile TAR in the literature, bone lysis with the AES prosthesis was more frequent with risk of subsidence. We therefore stopped implantation of this prosthesis and recommend preventive grafting for severe lysis.
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.
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.
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.
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.
Unlabelled:
Total ankle arthroplasty provides an alternative to arthrodesis for management of ankle arthritis. What is the outcome of total ankle arthroplasty implants currently in use? We conducted a systematic literature search of studies reporting on the outcome of total ankle arthroplasty. We included peer-reviewed studies reporting on at least 20 total ankle arthroplasties with currently used implants, with a minimum followup of 2 years. The Coleman Methodology Score was used to evaluate the quality of the studies. Thirteen Level IV studies of overall good quality reporting on 1105 total ankle arthroplasties (234 Agility, 344 STAR, 153 Buechel-Pappas, 152 HINTEGRA, 98 Salto, 70 TNK, 54 Mobility) were included. Residual pain was common (range, 27%-60%), superficial wound complications occurred in 0% to 14.7%, deep infections occurred in 0% to 4.6% of ankles, and ankle function improved after total ankle arthroplasty. The overall failure rate was approximately 10% at 5 years with a wide range (range, 0%-32%) between different centers. Superiority of an implant design over another cannot be supported by the available data.
Level of evidence:
Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Unlabelled:
Ankle arthroplasty is increasingly used to treat advanced ankle arthritis. Earlier prostheses have given way to second-generation implants, on which we are accumulating medium-term data. The Scandinavian Total Ankle Replacement (STAR) is a three-component uncemented implant in wide use in Europe and the only mobile-bearing prosthesis with conditional approval in the United States. We retrospectively reviewed 45 patients (52 ankles) who had primary total ankle replacements using STAR prostheses, in order to assess survivorship and add to the pool of clinical data provided by independent practitioners required to establish this treatment as a viable alternative to arthrodesis. The minimum followup was 60 months (range, 60-110 months). Clinical outcome was determined using the AOFAS score. We determined the rate of radiographic loosening and recorded complications and the need for further surgery. Survival was 90% (95% CI 76.8 to 95.5) at 5 years and 84% (95% CI 68.9 to 92.2) at 8 years. Six of 52 ankles (11%) had component revision and two were converted to fusion. The mean postoperative AOFAS score was 78. The complication rate was 21%. Subsequent surgery, excluding component revision, was performed in nine of 52 (17%) ankles.
Level of evidence:
Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
Background:
Mobile-bearing ankle replacements have become popular outside of the United States over the past two decades. The goal of the present study was to perform a prospective evaluation of the safety and efficacy of a mobile-bearing prosthesis to treat end stage ankle arthritis. We report the results of three separate cohorts of patients: a group of Scandanavian Total Ankle Replacement (STAR) patients and a control group of ankle fusion patients (the Pivotal Study Groups) and another group of STAR total ankle patients (Continued Access Group) whose surgery was performed following the completion of enrollment in the Pivotal Study.
Materials and methods:
The Pivotal Study design was a non-inferiority study using ankle fusion as the control. A non-randomized multi-centered design with concurrent fusion controls was used. We report the initial perioperative findings up to 24 months following surgery. For an individual patient to be considered an overall success, all of the following criteria needed to be met: a) a 40-point improvement in total Buechel-Pappas ankle score, b) no device failures, revisions, or removals, c) radiographic success, and d) no major complications. In the Pivotal Study (9/00 to 12/01), 158 ankle replacement and 66 arthrodesis procedures were performed; in the Continued Access Study (4/02 to 10/06), 448 ankle replacements were performed, of which 416 were at minimum 24 months post-surgery at time of the database closure.
Results:
Major complications and need for secondary surgical intervention were more common in the Pivotal Study arthroplasty group than the Pivotal Study ankle fusion group. In the Continued Access Group, secondary procedures performed on these arthroplasty patients decreased by half when compared with the Pivotal Arthroplasty Group. When the Pivotal Groups were compared, treatment efficacy was higher for the ankle replacement group due to improvement in functional scores. Pain relief was equivalent between fusion and replacement patients. The hypothesis of non-inferiority of ankle replacement was met for overall patient success.
Conclusion:
By 24 months, ankles treated with STAR ankle replacement (in both the Pivotal and Continued Access Groups) had better function and equivalent pain relief as ankles treated with fusion.
Between 2002 and 2008, 130 consecutive ankles were replaced with an hydroxyapatite (HA) and titanium-HA-coated Ankle Evolutive System total ankle prosthesis. Plain radiographs were analysed by two independent observers. Osteolytic lesions were classified by their size and location, with cavities > 10 mm in diameter considered to be ‘marked’. CT scanning was undertaken in all patients with marked osteolysis seen on the plain radiographs.
Osteolytic lesions were seen on the plain films in 48 (37%) and marked lesions in 27 (21%) ankles. The risk for osteolysis was found to be 3.1 (95% confidence interval 1.6 to 5.9) times higher with implants with Ti-HA porous coating.
Care should be taken with ankle arthroplasty until more is known about the reasons for these severe osteolyses.
Heterotopic ossification (HO) is a potentially severe, if infrequent, complication in hip surgery, and uncertainty exists regarding whether to use NSAIDs or radiation in its prevention. Thus, we systematically reviewed the literature in MedLine, EMBASE, CINAHL, and the Cochrane Controlled Trial Register and, after ruling out publication bias and data heterogeneity, performed a meta-analysis of randomized, controlled trials to assess effectiveness and complications of NSAIDs and radiation in the prevention of HO. We identified nine studies reporting on effectiveness and complications including a total of 1295 patients. The pooled risk ratio for the effectiveness in HO prevention was 0.96 (95% confidence interval, 0.88-1.06) and was independent of the type of surgery (THA or open reduction and internal fixation). There was no association with gender, age, length of followup, or year of publication. The risk ratio for associated complications was 0.79 (95% confidence interval, 0.45-1.41), and, again, was independent of the aforementioned factors. We found no evidence for a statistically significant or clinically important difference between NSAIDs or radiation in preventing HO.
There is a lack of detailed information about habitual physical activity levels and the sports participation of patients after total ankle arthroplasty.
The proportion of sports active patients increases after total ankle arthroplasty, and the majority of patients will meet current recommendations for health-enhancing physical activity.
Case series; Level of evidence, 4.
The authors assessed the pre- and postoperative participation in sports and recreational activities of 101 patients at a mean of 3.7 years after total ankle arthroplasty. Activity levels were determined with use of the University of California at Los Angeles (UCLA) activity scale. The International Physical Activity Questionnaire (IPAQ) was used to quantify habitual physical activity levels and to calculate the proportion of patients meeting current guidelines for health-enhancing physical activity. The American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score was used as the clinical outcome measure. Radiographs were studied for tibial and talar radiolucencies, and any association between radiolucencies, activity levels, and sports participation was determined.
Preoperatively, 62.4% of the patients were active in sports; 66.3% were active after surgery (P=.56). The patients were active in 3.0 +/- 1.8 different sports and recreational activities preoperatively and in 3.0 +/- 1.6 activities after surgery (P =1.0). The sports frequency remained unchanged, with 2.0 +/- 1.6 sessions per week before total ankle arthroplasty and 2.3 +/- 1.7 sessions per week postoperatively (P=.19). Overall, the patients were active in sports and recreation for 3.9 +/- 3.8 hours per week pre-operatively, and for 4.7 +/- 3.9 hours per week after surgery (P=.14). The most common disciplines after total ankle arthroplasty were swimming, cycling, and fitness/weight training. Sixty-five percent of the patients stated that surgery had improved their sports ability. The UCLA activity levels increased significantly from 4.3 +/- 2.2 to 6.2 +/- 1.6 (P<.001); AOFAS scores also improved significantly from 45.5 +/- 16.6 to 84.3 +/- 13.3 (P<.001). Patients suffering from posttraumatic ankle osteoarthritis were less satisfied with surgery than those with primary or inflammatory ankle osteoarthritis. Seventy-nine percent of the patients met the current guidelines for health-enhancing physical activity according to the IPAQ. Neither sports participation nor activity levels were associated with the presence of periprosthetic radiolucencies.
Two-thirds of the patients were active in sports after total ankle arthroplasty, and the majority of the patients met current health-enhancing physical activity recommendations. The clinical outcome as determined by AOFAS scores and the patient satisfaction were favorable. The present study found no association between sports participation, increased physical activity levels, and the appearance of periprosthetic radiolucencies 3.7 years after total ankle arthroplasty. However, these results have to be confirmed after longer follow-up, in particular of those patients regularly participating in sports with higher impact.
The first ankle prostheses appeared in 1973 as an alternative to ankle arthrodesis, which was until then the only valid solution for a painful degenerative, rheumatoid or posttraumatic ankle. Several designs followed, all with disappointing results. Low-constraint prostheses are now being used, with literature studies of 5 years follow-up. In this study, the authors have evaluated the results of 26 uncemented, hydroxyapatite-coated STAR prostheses, all implanted between January 1996 and December 1999, with an average follow-up of 15.8 months (range: 1.5 to 48 months). For evaluation, all patients filled out a questionnaire at three different moments in time, and all of them were clinically reviewed by one single observer. The Kofoed ankle score was used for clinical evaluation. All ankle prostheses were also radiographically reviewed, using a radiographic scoring system developed by the authors. Evaluation with the Kofoed ankle score showed 74% favourable results. When patients were asked to rate their satisfaction on a scale between 0 and 100, an average improvement of 50/100 was reached. Pain was the most important indication to surgery and is the only parameter that can be predictably influenced. The effects on motion and walking distance are less predictable. No major complications occurred and there were no revision operations. Should prosthetic failure occur, an arthrodesis can still be performed, as bone resection in the primary procedure has been minimal.
A porous-coated, cementless, congruent-contact, three-piece, meniscal-bearing total ankle replacement was developed and used clinically over a 2- to 10-year period for patients with disabling ankle arthritis. Polished titanium-nitride ceramic-coated Ti6Al4V tibial and talar components with a deep-sulcus trochlear groove and two lateral fixation fins for the talar onlay component were used. The ultra-high-molecular-weight polyethylene (UHMWPe) meniscal bearing congruently conformed to the flat upper tibial component surface and the deep sulcus and cylindrical geometry of the lower talar component surface. Fifty deep-sulcus (Buechel-Pappas) total ankle replacements were implanted in 49 patients. Diagnoses were 8 osteoarthritis (16%), 7 rheumatoid arthritis (14%), 2 avascular necrosis (4%), and 33 post-traumatic arthritis (66%). Ages ranged from 26 to 71 years (mean 49 years). Clinical results using a strict ankle scoring system demonstrated good/excellent results in 88% of cases. Postoperative ankle motion ranged from 12 degrees to 46 degrees total arc (mean 28 degrees), which was similar to the preoperative motion. Revision for malalignment was necessary in two cases (4%). Mechanical complications included one case of meniscal bearing wear (2%) in a patient with post-traumatic arthritis with component malalignment and one case of talar component subsidence (2%) in a patient with avascular necrosis of the talus. No tibial component loosening was seen. Cumulative survivorship using an end point of revision of any component for any reason was 93.5% at 10 years (confidence interval 61-100%).
Total ankle replacement is a possible treatment for ankle arthritis; however, participation in sports after this procedure has not yet been analyzed.
There is a significant increase of sports activity after total ankle replacement in patients with arthritis. There is a significant correlation between sports activity and American Orthopaedic Foot and Ankle Society hindfoot score in patients after total ankle replacement.
Case series; Level of evidence, 4.
A clinical evaluation was performed preoperatively and at follow-up after total ankle replacement in 147 patients (152 ankles) with ankle arthritis (mean age, 59.6 years; range, 28-86 years). Ankle arthritis origin, patient satisfaction, range of motion, American Orthopaedic Foot and Ankle Society hindfoot score, radiologic assessment, and rate, level, and type of sports activity were documented at both evaluations. The mean follow-up was 2.8 years (range, 2-4 years).
Preoperative diagnosis was posttraumatic osteoarthritis in 115 cases (76%). At total ankle replacement follow-up, excellent and good outcomes were reported in 126 cases (83%); 105 cases (69%) were pain free. The mean range of motion pre-operatively was 21 degrees (range, 0 degrees -45 degrees ); after total ankle replacement, it was 35 degrees (range, 10 degrees -55 degrees ; P < .05). The preoperative American Orthopaedic Foot and Ankle Society score was 36 points; after total ankle replacement, it was 84 points (P < .001). Before surgery, 36% of the patients were active in sports; after surgery, this percentage rose to 56% (P < .001). After total ankle replacement, sports-active patients showed a significantly higher hindfoot score than did patients not active in sports: 88 versus 79 points (P < .001). The 3 most frequent sports activities were hiking, biking, and swimming.
There was a significant increase of sports activity by treating ankle arthritis patients with total ankle replacement. Sports-active total ankle replacement patients showed better functional results than did inactive ones.
There have been few reports of large series of ankle replacements. The aim of this study was to document and evaluate the early results of a nationwide series of total ankle replacements (TARs) performed using second- and third-generation implants.
Records of total ankle replacements performed between February 2000 and November 2005 were retrieved from the New Zealand National Joint Registry and retrospectively reviewed at a mean of 28 months after the primary procedure. At 6 months post surgery, patient scores were generated from questionnaires. Comparisons between patient scores and categorical variables were made using ANOVA. Regression analyses using Cox proportional-hazards modeling were performed to determine predictors of failure. A Kaplan-Meier survivorship curve was used to describe the rate of prosthetic survival.
202 total ankle replacements were performed in 183 patients. 14 prostheses (7%) failed. The overall cumulative 5-year failure-free rate was 86%. An unfavorable patient score at 6 months after the initial procedure turned out to be a good predictor of subsequent failure. The cumulative 5-year failure-free rate was 65% at 5 years for patients with an unfavorable score, and 95% for those who had a favorable patient score. Each 1-point increase in the patient score (i.e. poorer outcome) corresponded to a 5% relative increase in the risk of failure (p < 0.05). In addition, longer operative time for the primary procedure was found in the group of TARs that subsequently failed (p < 0.05).
The National Joint Registry appears to be a useful tool for monitoring the trends in TAR surgery.
There have been few reports on the long-term outcome of ankle replacements. The Norwegian Arthroplasty Register has been registering ankle replacements since 1994, but no analysis of these data has been published to date. Here we report data on the use of total ankle replacements and the revision rate in the Norwegian population over a 12-year period.
We used the Norwegian Arthroplasty Register to find ankle arthroplasties performed between 1994 and 2005. Patient demographics, diagnoses, brands of prosthesis, revisions, and time trends were investigated.
There were 257 primary ankle replacements, 32 of which were cemented TPR prostheses and 212 of which were cementless STAR prostheses. The overall 5- year and 10-year survival was 89% and 76%, respectively. Prosthesis survival was the same for the cementless STAR prosthesis and the cemented TPR prosthesis. There was no significant influence of age, sex, type of prosthesis, diagnosis, or year of operation on the risk of revision. The incidence of ankle replacements due to osteoarthritis, but not due to inflammatory arthritis, increased over the years.
The revision rate was acceptable compared to other studies of ankle arthroplasties, but high compared to total knee and hip arthroplasties. The overall incidence of ankle replacements increased during the study period.
Preoperative deformity in the frontal plane in the arthritic ankle is a risk factor for failure after total ankle arthroplasty. Medial malleolar lengthening osteotomy was developed to correct varus malalignment.
From 1998 to 2005 total ankle arthroplasty combined with medial malleolar lengthening osteotomy was done in 15 ankles (13 patients) with a mean preoperative varus deformity of 14.9 (SD, 7.8) degrees. Diagnosis was arthritis with instability in 11 ankles (9 patients) and inflammatory joint disease in 4 ankles. Two mobile-bearing designs were used. Osteosynthesis of the osteotomy was done in 2 ankles; for the remaining 13 osteotomies, no fixation was used.
Followup was 5 (range 2 to 8) years. Neutral alignment was obtained in all ankles. In 3 patients residual hindfoot varus remained, for which a second-stage hindfoot correction was done. Two rheumatoid ankles developed a symptom-free nonunion of the medial malleolus, all other malleolar osteotomies united. One tibial component, implanted with too much anterior slope, developed early aseptic loosening and was revised. Debridement for talar-malleolar arthritis was done in two ankles. Of the 14 ankles in followup, 12 were rated as excellent or good, one as fair. One ankle with subsidence of the talar component was rated as unsatisfactory. AOFAS score increased from 30.8 preoperative to 81.0 at followup (p < 0.01).
Medial malleolar lengthening osteotomy is an easy technique for the realignment of the varus ankle at the time of total ankle arthroplasty, and served as an alternative to medial ligament release or lateral ligament reconstruction.
All formulations of commercially available highly crosslinked ultra-high molecular weight polyethylene (UHMWPE) have demonstrated dramatic reduction in wear compared to conventional UHMWPE. A majority of these demonstrations have been under "smooth," i.e., non-abrasive conditions. The question, therefore, remains: are contemporary highly crosslinked UHMWPE (XPE) materials suitable for both hips and knees under abrasive conditions in vivo? These studies examined both XPE (10Mrad, GUR1050) and non-irradiated UHMWPE (GUR1050) for hips and knees under smooth and abrasive conditions. Studies were conducted on a 12-station hip and 6-station knee simulator. The femoral components were left polished or tumbled with plastic cones and alumina powder to create uniform scratching with surface roughness similar to clinical retrievals. In smooth conditions, XPE wore significantly less than non-irradiated UHMWPE (CPE) for both hips and knees. In abrasive conditions, wear of XPE increased by at least 15 times in hip applications and at least 70 times in knee applications. Furthermore, XPE knees wore more than CPE knees in the abrasive condition. This study showed that both forms of UHMWPE were subject to accelerated wear under abrasive conditions; however, the sensitivity of XPE to abrasive wear was greater for knees than for hips. These findings need to be taken into consideration when developing materials for improved wear resistance in knees.
Between 1993 and 2000 we implanted 200 cementless, mobile-bearing STAR total ankle replacements. None was lost to follow-up for reasons other than the death of a patient. The mean follow-up was for 46 months (24 to 101).
A complication requiring further surgery developed in eight ankles and 14 were revised or fused. The cumulative survival rate at five years was 92.7% (95% CI 86.6 to 98.8) with time to decision to revision or fusion as an endpoint.
The most frequent complications were delayed wound healing and fracture of a malleolus. These became less common with experience of the operation. The radiological appearance of the interface of the tibial implant was significantly related to its operative fit and to the type of bioactive coating.
In a prospective series of 100 total ankle arthroplasties 8 patients had a lateral instability > 20° (20°- 35°). In 1 case the reconstruction was done by shortening of the capsule and refixation to the anterolateral corner, in 7 cases (4 ♂, 3♀) the reconstruction was done by a transfer of the peroneus brevis tendon from posterior into in a fibular groove, which is created at the anterior edge of the fibula. Fixation was performed with two suture anchors. The reconstruction is done extraarticular. The clinical and radiological follow up examination was done 3 – 24 month after the index surgery. In all patients there was a complete restoration of the lateral stability, and the average ROM of the ankle joint was 48° (38 – 64). There were no intra- or postoperative complications
Heterotopic ossification following lower-limb joint arthroplasty is a challenging clinical problem. No comprehensive study has been conducted on heterotopic ossification after total ankle arthroplasty, to our knowledge. The purpose of this study was to evaluate the prevalence and location of heterotopic ossification after primary total ankle arthroplasty, predisposing factors, and effects on clinical outcomes, and to develop a method of classification.
Eighty ankles in eighty patients with a primary total ankle arthroplasty were followed for a mean (and standard deviation) of 31.9 ± 11.3 months (range, twenty-four to sixty-five months). The prevalence and location of heterotopic ossification, predisposing factors, and outcomes were analyzed, and a method of classification was developed.
Twenty (25%) of the eighty ankles demonstrated postoperative heterotopic ossification, with the majority of the cases in the posterior aspect of the ankle. The heterotopic ossification was Class I in four cases (20%); Class II, in five (25%); Class III, in four (20%); and Class IV, in seven (35%). Symptomatic heterotopic ossification was reported in eight patients (10%), and two required surgical resection because of intractable pain. Ankles that developed heterotopic ossification had significantly longer operative times, less postoperative motion, and lower American Orthopaedic Foot & Ankle Society ankle-hindfoot scores at the six, twelve, and twenty-four-month follow-up examinations (p < 0.05 for all).
This study demonstrates that the prevalence of heterotopic ossification following primary total ankle arthroplasty is considerable, and that heterotopic ossification is associated with reduced ankle motion and a poor clinical outcome at a mean of two years postoperatively. Care is needed to attempt to reduce the occurrence of heterotopic ossification.
In a systematic review, reports from national registers and clinical studies were identified and analysed with respect to revision rates after joint replacement, which were calculated as revisions per 100 observed component years.
After primary hip replacement, a mean of 1.29 revisions per 100 observed component years was seen. The results after primary total knee replacement are 1.26 revisions per 100 observed component years, and 1.53 after medial unicompartmental replacement. After total ankle replacement a mean of 3.29 revisions per 100 observed component years was seen.
The outcomes of total hip and knee replacement are almost identical. Revision rates of about 6% after five years and 12% after ten years are to be expected.
Some previous studies have shown a high percentage of early-onset and rapidly progressing osteolysis associated with total ankle arthroplasty (TAA) by the Ankle Evolutive System (AES). The purpose of our study was to analyze medium-term results at our institution.
Altogether 38 TAAs using AES prostheses were carried out between 2003 and 2007. Diagnoses were rheumatoid arthritis (71%), post-traumatic and idiopathic osteoarthritis (29%). The mean age was 54 years, followup 28 months. Tibial and talar components had hydroxyapatite coating on metal (Co-Cr) components (HA-coated). Since 2005 the design was changed and components were porous coated with titanium and hydroxyapatite (dual-coated).
Two-year survival was 79% (95% CI: 56 to 98). At followup 34 (89%) primary tibial and talar components were preserved. In 19 (50%) TAAs osteolysis (more than or equal to 2 mm) occurred in the periprosthetic bone area and in nine (24%) comprised large "cyst-like osteolysis''. In HA-coated prostheses radiolucent lines (less than or equal to 2 mm) or osteolysis (more than or equal to 2 mm) were detected in 11 (100%) cases and in dual-coated prostheses in 19 (74%) (p = 0.08). On the other hand there was more large "cyst-like osteolysis'' around the dual-coated prosthesis and lesions were larger (p = 0.017). In rheumatoid arthritis osteolysis was detected in 14 (52%) and large "cyst-like osteolysis'' in seven (26%) prostheses and in the group of traumatic and idiopathic osteoarthritis in six (55%) and two (18%), respectively.
This study showed a high frequency of osteolysis in medium-term followup after the AES ankle replacement. The outcome was not sufficiently beneficial and we have discontinued use of this prosthesis.
The anterior incision used for the insertion of total ankle arthroplasty systems is at high risk for wound complications, and little has been documented regarding who is at risk for the development of these complications.
We conducted a retrospective chart review of 106 total ankle arthroplasties. Independent risk variables, including age, sex, body-mass index, diabetes, smoking, medications, preoperative diagnosis, implant size, tourniquet time, closure method, and anticoagulation status, were recorded. Postoperative office notes were reviewed for wound-related complications. Outcomes were divided into three categories: no complications (uncomplicated wound-healing), minor complications (wounds requiring only local care/oral antibiotics), and major complications (requiring a return to the operating room for treatment). Simultaneously, categorical variables were compared with use of chi-square analysis. Multivariate logistic regression and odds ratio assessment were performed as well.
When patients who had no complications were compared with those who had minor complications, a history of diabetes was the only variable that was identified as resulting in a significant risk increase (p = 0.04). When patients who had no wound complications or minor wound complications were compared with those who had major wound complications, female sex, a history of corticosteroid use, and underlying inflammatory arthritis were all associated with increased risk. Multivariate logistic regression demonstrated underlying inflammatory arthritis (p = 0.004) to be the only significant risk factor for major wound complications, with an odds ratio demonstrating a 14.03 times increased risk of requiring reoperation.
We recommend that caution be used when selecting and educating patients with inflammatory arthritic conditions who are potential candidates for total ankle arthroplasty.
Objectives:
After more than 10 years' experience in France, the French Foot Surgery Association (Association française de chirurgie du pied [AFCP]) presents an update on mobile-bearing ankle prostheses, based on a multicenter study. META-ANALYSIS - BIOMECHANICS - ASSESSMENT AND INDICATIONS: A preliminary comparative meta-analysis of the literature studies on ankle and prosthesis biomechanics, reviews validated indications and contra-indications, and details clinical and radiological outcomes assessment protocols.
Professional survey:
Sixty-three surgeons (95% AFCP members) answered a professional online survey, by email or regular post: 70% performed total ankle replacement (TAR), 39% of them at least two per year and 16% more than 10 per year, resulting in 317 TARs per year or 50% of the French activity and 312 arthrodeses per year or 17% of the French activity - which gave the survey considerable power. In 2004-2005, 46% of the TARs implanted were AES, 38% Salto and 9% Hintegra.
Gait analysis following tar:
This study included two series of patients (15 in Brussels and six in Paris) with laboratory gait analysis preoperatively and at 6 months' and 1 year's FU. Following TAR, speed, cadence and strides increased and mean total work approximated normal values. These two independent studies quantified the advantages of TAR over arthrodesis.
Multicenter study:
This retrospective study had a minimum follow-up of 1 year. Results were not distinguished between the four types of prosthesis (approved by the French Healthcare Agency [HAS]) involved. Inclusion criteria for operators were: AFCP membership, and experience of more than 20 prostheses of a given type. Twelve out of 15 centers responded and undertook to include continuous series. Data were centralized on a dedicated anonymous online site. Five hundred and ninety-two TARs (388 Salto, 173 AES, 22 Hintegra, nine Star) in 555 patients (mean age, 56.4 years; range 17-84 yrs) were included. Indications were post-traumatic arthritis (48%), arthritis associated with laxity (15%), inflammatory arthropathy (20%), primitive arthritis (9%), prosthetic revision (2%), and miscellaneous (5%). Sixty-one percent of operations included associated procedures: 208 Achilles lengthenings, 45 subtalar arthrodeses, nine calcaneal osteotomies and 45 lateral ligament reconstructions. Complications comprised 53 malleolar fractures, and 39 cutaneous and seven infections (9%). At a mean 37 months' FU, 87.5% of patients were satisfied or very satisfied; mean functional score was 82.1/100; radiographic mobility, 23.2 degrees ; and total SF 36 score (on the Short Form Health Survey), 66. X-ray found stable anchorage in 98% of cases, cysts in 15%, and calcification in 4%.
Revision for failure:
Overall cumulated survivorship was 88% at 71 months: 22 patients underwent arthrodesis (61% satisfied), and 10 implant replacement (50% satisfied).
Conclusion:
This multioperator, multi-implant series of 592 patients confirmed literature data. Prospective follow-up of the cohorts managed in these expert centers is essential, in order to make available long-term data.
The method of choice for the treatment of severe ankle arthritis is either arthrodesis or joint arthroplasty. Each has its advantages and disadvantages. Arthrodesis is the definitive therapy for severe ankle destruction and instability. Joint arthroplasty has an advantage in maintaining ankle mobility. However, its range of indications and its reliability and durability are more limited. The aim of this study is to present our experience with the AES prosthesis and draw attention to some drawbacks of this surgical treatment.
From September 2003 till June 2008, 51 AES ankle replacements were carried out in 51 patients (33 women and 18 men). Their average age at the time of surgery was 53.8 years. The youngest patient was 23 and the oldest was 88 years old. The indication for surgery was rheumatoid arthritis in 10, primary arthritis in six and post-traumatic ankle arthritis in 35 patients.
The patients were evaluated in 2008. The follow-up ranged from 4 months to 5 years. The patients were examined for ankle joint mobility and pain. Radiographs were assessed for potential signs of component loosening.
The results presented here are short-term ones. The pre-operative AOFAS score of 33.7 increased to 82.3 points post-operatively. The range of motion was on average 20 degrees of plantar flexion and 5 to 10 degrees of dorsiflexion. Thirty- five patients (68.7 %) were free from pain, 11 (21.5 %) experienced slight pain while walking, and five (9.8 %) patients reported more intensive pain in the joint treated. Intra-operative complications included a fracture of the medial malleolus in two (3.9 %) patients subsequently treated with screw osteosynthesis. Post-operatively, seven (13.7 %) patients experienced slow healing of the operative wound. One patient had dislocation of the polyethylene liner at 3 months after surgery. Revision surgery was carried out in seven (13.7 %) patients. Two patients suffering from increasing pain around medial malleolus underwent revision and removal of ossifications. One patient developed necrosis of the talus at 1 year after surgery. She underwent extraction of the prosthesis and ankle arthrodesis with a retrograde locking nail inserted through the heel. A large bony effect arising due to extraction of the necrotic talus was repaired using bone graft. Three (5.8 %) patients developed post-operative instability of the ankle that required revision surgery. The radiographs of another three (5.8 %) patients showed bone cysts and signs of tibial component loosening. Of these, one patient underwent surgical revision with replacement of the polyethylene liner. Cavities were freed from granuloma induced by polyethylene wear debris, and filled with bone graft from the iliac crest.
Total ankle replacement is a complicated surgical procedure that may results in various technical difficulties and complications. These are inversely proportional to the surgeon's experience, as also shown by literature data.
The longevity of a total ankle replacement depends, much more than in other joint replacements, on an accurate implantation technique and correct indication.
We report a retrospective study of 62 total ankle arthroplasties performed between 1972 and 1981. Forty-one of these have been reviewed clinically after an average follow-up of five and a half years; only 13 can be described as satisfactory. The complications encountered in all 62 arthroplasties are detailed, the most significant being superficial wound healing problems, talar collapse, and loosening of the components; 13 prosthetic joints have already been removed and arthrodesis attempted. The management of the complications is discussed. In view of the high complication rate and the generally poor long-term clinical results, we recommend arthrodesis as the treatment of choice for the painful stiff arthritic ankle, regardless of the underlying pathological process.
A method to classify the degree of ectopic bone formation about the hip following total hip arthroplasty revealed that 21% of 100 consecutive patients treated by total hip arthroplasty had ectopic bone formation about the hip of various degrees when reviewed 6 mth following operation. Ectopic bone formation, however, did not seem to affect the functional result as judged by the Harris hip evaluation unless apparent bone ankylosis resulted.
A prosthesis for the ankle joint that I designed in 1973 was implanted in fifty patients who otherwise would have required fusion of the ankle to relieve severe pain. The design of the device allows about as much motion as in the normal ankle. During implantation of the prosthesis the dome of the talus is not resected and only one centimeter of the distal end of the tibia is removed. If the prosthetic replacement is unsuccessful, fusion of the ankle can more easily be achieved secondarily if it should become necessary. Review of the cases of these fifty patients showed that the best results were obtained in the patients with degenerative arthritis whose ankles were stable and not unduly deformed. A few patients with rheumatoid arthritis (four of ten) who were not on long-term steroid therapy also did well. Contraindications revealed by my experience include avascular necrosis of the talus, pseudarthrosis at the site of a previously attempted ankle fusion, and conditions causing talar tilt of 20 degrees or more.
We evaluated the intermediate-term results of a novel total ankle arthroplasty that includes insertion of the components without cement and arthrodesis of the tibiofibular syndesmosis as part of the operative procedure. One hundred consecutive Agility ankle replacements were performed in ninety-five patients between 1984 and 1993. At the time of follow-up, eighty-three patients (eighty-six ankles) were alive and twelve patients (fourteen ankles) had died. Five (6 per cent) of the eighty-six ankles in the living patients had been revised. Including the components that had been revised for loosening, twenty-one (twelve tibial and nine talar) components had migrated. Delayed union of the syndesmosis (twenty-eight ankles) and non-union of the syndesmosis (nine ankles) were associated with the development of lysis around the tibial component. Non-union of the syndesmosis was also associated with migration of the tibial component and circumferential radiolucency around that component. In addition to the patients who died, one patient had a resection of the implant with subsequent arthrodesis. The remaining eighty-two patients (eighty-five ankles) were the basis for the clinical evaluation in the study. The average age at the time of the procedure was sixty-three years (range, twenty-seven to eighty-one years). At the time of the most recent follow-up (range, 2.8 to 12.3 years; average, 4.8 years), forty-seven (55 per cent) of the remaining eighty-five ankles were not painful and twenty-four (28 per cent) were only mildly painful. The range of motion of the fifty-six ankles that were examined at the time of follow-up averaged 36 degrees (range, 10 to 64 degrees), and the results for seventy-nine (93 per cent) of the eighty-five ankles were satisfactory to the patients.
Between 1993 and 2000 we implanted 200 cementless, mobile-bearing STAR total ankle replacements. None was lost to follow-up for reasons other than the death of a patient. The mean follow-up was for 46 months (24 to 101). A complication requiring further surgery developed in eight ankles and 14 were revised or fused. The cumulative survival rate at five years was 92.7% (95% CI 86.6 to 98.8) with time to decision to revision or fusion as an endpoint. The most frequent complications were delayed wound healing and fracture of a malleolus. These became less common with experience of the operation. The radiological appearance of the interface of the tibial implant was significantly related to its operative fit and to the type of bioactive coating.
The feasibility of replacing the ankle joint has been a matter of speculation for a long time. In recent years, the designs of ankle prostheses have been improved, and three designs, all used without bone cement, currently dominate the market. However, documentation of the clinical results of the use of these prostheses is sparse. We reviewed the intermediate-term results of fifty-one consecutive Scandinavian Total Ankle Replacements (STAR).
Between 1993 and 1999, fifty-one consecutive ankles were replaced with an uncemented, hydroxyapatite-coated STAR total ankle prosthesis. Clinical examination for the present study was performed by one surgeon who had not taken part in the operations. Standardized radiographs were used. Complications and failures were recorded, and patient satisfaction and functional outcome scores were determined for all patients with an unrevised implant.
Twelve ankles had to be revised. Seven were revised because of loosening of at least one of the components; two, because of fracture of the meniscus; and three, for other reasons. A component was exchanged in seven of the twelve revisions, whereas the ankle was successfully fused in the other five. An additional eight ankles had radiographic signs of loosening. The thirty-nine unrevised ankles (thirty-seven patients) were examined after thirty-six to ninety-seven months (median, fifty-two months). The patient was satisfied with the result after thirty-one of the ankle replacements, somewhat satisfied after two, and not satisfied after six. The median Kofoed score increased from 39 points before the surgery to 70 points at the time of the follow-up examination. A median follow-up score of 74 points was recorded when the system described by Mazur et al. and the AOFAS (American Orthopaedic Foot and Ankle Society) system were used. The median range of motion was approximately the same preoperatively and postoperatively. The estimated five-year survival rate, with revision for any reason as the end point, was 0.70. When radiographic loosening of either component was used as the end point, the estimated five-year radiographic survival rate was significantly better for the last thirty-one ankles treated in the series (p = 0.032).
Total ankle replacement may be a realistic alternative to arthrodesis, provided that the components are correctly positioned and are of the correct size. However, the risks of loosening and failure are still higher than are such risks after total hip or total knee replacement.
Second-generation total ankle arthroplasty has been reported to have good intermediate-term results. The purpose of the present study was to report on the cause and frequency of reoperation and failure after total ankle arthroplasty and to determine demographic and clinical predictors of reoperation and failure.
Three hundred and six consecutive primary total ankle arthroplasties were performed with use of the DePuy Agility Total Ankle System between 1995 and 2001. At a mean of thirty-three months after the arthroplasty, we retrospectively reviewed the records with regard to patient age, gender, the indications for the index procedure, adjuvant procedures, the timing and frequency of reoperation, and the indications for and the type of reoperations performed. Kaplan-Meier analysis was performed to determine the rate of prosthetic survival, and Cox regression analysis was performed to determine predictors of reoperation and failure.
Eighty-five patients (28%) underwent 127 reoperations (involving 168 procedures) after primary total ankle arthroplasty. The most common procedures at the time of reoperation were débridement of heterotopic bone (fifty-eight), correction of axial malalignment (forty), and component replacement (thirty-one). Eight patients underwent below-the-knee amputation. Age was found to be the only significant predictor of reoperation and failure after total ankle arthroplasty. The five-year survival rate with reoperation as the end point was 54%. The five-year survival rate with failure as the end point was 80% for all patients and 89% for patients who were more than fifty-four years of age. The prosthesis could not be salvaged in nine ankles (2.9%); the inability to salvage the prosthesis was most often due to loosening or infection.
We noted a relatively high rate of reoperation after total ankle arthroplasty with this second-generation device. Younger age was found to have a negative effect on the rates of reoperation and failure. Most prostheses could be salvaged; however, the functional outcome of this procedure is uncertain.
We previously reported the intermediate-term results with the early version of the Agility total ankle replacement, a unique design that takes advantage of arthrodesis of the tibiofibular syndesmosis for tibial component support. The purpose of this study was to report longer-term results of this procedure in the treatment of disabling ankle arthritis.
We conducted an independent review of all Agility total ankle replacements performed by a single surgeon between 1984 and 1994. Follow-up evaluation consisted of completion of a validated ankle osteoarthritis scale and a short questionnaire and a review of the radiographs. All radiographs were evaluated for evidence of the development of progressive hindfoot arthritis, nonunion of the tibiofibular syndesmosis, progressive radiolucent lines, osteolysis, and component subsidence.
One hundred and thirty-two arthroplasties were performed in 126 patients. After a mean follow-up period of nine years, thirty-three patients (thirty-six implants) had died, fourteen patients (11%) had a revision of the implant or an ankle arthrodesis, and one had the leg amputated because of an unrelated cause. Of the remaining seventy-eight patients (eighty-one ankles), sixty-seven (sixty-nine ankles) were followed clinically. More than 90% of them reported that they had decreased pain and were satisfied with the outcome of the surgery. We found modest differences in a comparison of the pain and disability scores with those of age-matched controls. Of the 117 ankles that had been followed radiographically for a minimum of two years, twenty-two (19%) had progressive subtalar arthritis, seventeen (15%) had progressive talonavicular arthritis, and nine (8%) had a syndesmosis nonunion. Eighty-nine (76%) of the 117 ankles had some evidence of peri-implant radiolucency.
Arthrodesis of the tibiofibular syndesmosis impacts the radiographic and clinical outcomes with the Agility total ankle replacement. The relatively low rates of radiographic hindfoot arthritis and revision procedures at an average of nine years after the arthroplasty are encouraging. Agility total ankle replacement is a viable and durable option for the treatment of ankle arthritis in selected patients.
Ankle arthroplasties using metal and polyethylene prostheses were done on 28 patients (30 ankles) with painful osteoarthritis or rheumatoid arthritis between 1975 and 1980. Significant loosening and subsidence of the metal prostheses occurred in most patients, and ceramic prostheses were introduced in 1980. Ceramic prostheses with or without cement were used to replace 60 ankles in 56 patients with painful arthritis between 1980 and 1991. Revision surgery was required for five patients (five ankles) during the followup period (mean, 12 years 6 months). Loosening and subsidence of the prostheses were seen in 50% of patients within 5 years after the index procedure. As a result, a new design of bead-formed alumina coated with hydroxyapatite was used. A tibial prosthesis fixed to the posterior cortex of the tibia with a screw was used from 1991. These new ceramic prostheses were used to replace 70 ankles in 62 patients between 1991 and 2000. Thirty-six patients (36 ankles) with a mean age of 71 years (range, 50-87 years) had osteoarthritis, and 26 patients (31 ankles) with a mean age of 60 years (range, 41-76 years) had rheumatoid arthritis. During followup, with an average of 5 years 2 months, three patients (three ankles) required revision surgery (one for infection, two for talar necrosis). Overall results for patients with osteoarthritis were excellent in 21 ankles, good in 10 ankles, fair in two, ankles and poor in zero ankles. Results in patients with rheumatoid arthritis were excellent in five ankles, good in 16 ankles, fair in three ankles, and poor in two. In the intermediate study, 29 patients (31 ankles; 91.2%) with osteoarthritis and 19 patients (21 ankles; 76.9%) with rheumatoid arthritis were satisfied with the short-time results of arthroplasty.
There has been a resurgence in the treatment of end-stage tibiotalar arthritis with prosthetic replacement. This procedure has highlighted numerous complications including malleolar fracture. We wanted to determine the clinical relevance of malleolar fracture with the two most commonly used implants in the United States. We retrospectively compared the first 20 STAR with the first 25 Agility total ankle arthroplasties done by two surgeons. We examined the fracture rate, the timing, location, and treatment of the fracture, and the outcome in each group. In the Agility group, five fractures occurred, all intraoperatively. Four involved the medial malleolus and one involved the lateral malleolus. All fractures were fixed as implant stability was compromised. In the STAR group, there were four fractures. Two lateral malleoli fractured intraoperatively and were fixed. Two medial malleoli fractures occurred postoperatively and were treated nonoperatively. There was one medial malleolar nonunion in each group. The incidence of malleolar fracture was 20% in each group, comparable to results reported in relevant literature. We highlight some of the causes of malleolar fracture and describe our technique of prophylactic malleolar pinning to prevent this complication. Malleolar fracture is clinically relevant with the Agility and STAR implants and should be anticipated and prevented.
The treatment of coronal plane deformity during total ankle arthroplasty is understood poorly. This study tests the hypotheses that preoperative coronal plane malalignment and incongruence of the ankle can be corrected and maintained for 2 years with total ankle replacement, and that factors can be identified that place ankles at risk of having progressive edge-loading develop. Of 86 consecutive patients who had total ankle replacement, 35 had preoperative coronal plane alignment > or =10 degrees. Lateral ligament reconstruction was done in seven patients and superficial deltoid release was done in four patients at the time of ankle replacement. Ankles with talar and tibial deformities improved talar and tibial alignment toward a neutral weightbearing axis postoperatively. Ankles with only a talar deformity improved the talar alignment toward a neutral weightbearing axis postoperatively. No changes in alignment were shown during the subsequent 2 years. Postoperative ankle articulations were congruent. Patients with preoperative incongruent joints are 10 times more likely to have progressive edge-loading develop than patients with congruent joints. Surgeons must be attentive to coronal plane alignment during and after ankle replacement. Longer followup is needed to assess the longevity of the correction and the impact of minor malalignment on implant wear.
Fifty-eight patients with either rheumatoid arthritis or osteoarthritis were treated with meniscal-bearing ankle prostheses. The concept was to mobilize, align, and stabilize the ankle before resurfacing it. Cement was used for prostheses fixation in 33 patients (1986-1989) and 25 patients had fixation without cement (1990-1995). All patients in one prospective series were followed up yearly with radiographs and with a clinical scoring system giving a maximum of 100 points. This allowed for a patient-controlled prospective study. No patients were lost to followup. The only detectable difference in the treatment was the fixation mode. For the purpose of comparing patients with cemented and uncemented prostheses, the patients who had surgery between 1986 and 1989 were not followed up after 1997, and patients who had surgery between 1990 and 1995 were not followed up after 2002. The mean followup was 9.4 years. Failure was defined as prosthesis revision or change to arthrodesis for any reason. In the cemented group, nine of 33 patients had revision surgery or fusion. In the uncemented group, one of 25 patients had revision surgery. Survivorship analysis for 12 years based on life tables showed a 70% survival rate (confidence limit, 60.3-78.5) for the cemented group and 95.4% survival rate (confidence limit, 91.0-99.9) for the uncemented group. The average clinical scores at the latest followup were 74.2 +/- 19.3 for the cemented group and 91.9 +/- 7.4 points for the uncemented group. Therefore, unconstrained meniscal-bearing ankle prostheses should be uncemented.
The HINTEGRA ankle was developed as an attempt to specifically address the needs of minimal bone resection, extended bone support, proper ligament balancing, and minimal contact stresses within and around the prosthesis. The purpose of this study was to determine the short-term results in a consecutive series of 116 patients (122 ankles). Preoperative diagnoses were posttraumatic osteoarthrosis in 91 ankles (75%), primary osteoarthrosis in 16 ankles (13%), and systemic arthritis in 15 ankles (12%). Eight ankles had to be revised. Four were revised because of loosening of at least one component; one because of dislocation of the meniscus; and three for other reasons. All revisions were successful. After an average of 18.9 months (range, 1-3 years), 84% of patients were satisfied, and the clinical result was rated as good or excellent in 82% of the cases. The American Orthopaedic Foot and Ankle Society hindfoot score improved from 40 points preoperatively to 85 points at followup. Eighty-three ankles (68%) were completely pain-free. The average range of motion clinically was 39 degrees (range, 15 degrees-55 degrees) and under fluoroscopy (true ankle motion) it was 37 degrees (range, 7 degrees-62 degrees). Radiographically, the tibial component was stable in all ankles, and no tilting of the component occurred since surgery. However, migration of the talar component was observed in two ankles. The concept of minimal bone resection and wide bony support was shown to be successful on the tibial and talar sides. Obtained function, pain relief, and patient satisfaction were promising and, compared with other devices, the results mostly were superior. This may support the idea that anatomic-shaped surfaces, as is the case in the HINTEGRA ankle, may be successful in total ankle replacement.
The purpose of the current prospective study was to determine the midterm results of 68 total ankle replacements with the Scandinavian Total Ankle Replacement (S.T.A.R.) prosthesis. The 65 patients (34 women and 31 men; mean age at surgery, 56.1 years [range, 22-85 years]) were assessed clinically and radiologically after 3.7 years (range, 2.4-6.2 years). Thirty-five patients (54%) were totally pain-free. The overall clinical score was graded as excellent or good in 67 ankles. The American Orthopaedic Foot and Ankle Society hindfoot score improved from 24.7 points (range, 3-44 points) preoperatively to 84.3 points (range, 44-100 points) at followup. Three patients (three ankles, 4.4%) had a ballooning bone lysis on the tibial side. Despite prophylaxis, periarticular hypertrophic bone formation was seen in 43 ankles (63%; 42 patients), associated with a decrease of dorsiflexion and plantar flexion. Nine ankles (13%; nine patients) had revision surgery because of problems with the components and 14 ankles (21%; 14 patients) had secondary or additional operations. All revision or secondary surgeries were successful, and no ankle had to be converted to an ankle arthrodesis. The early experience with the S.T.A.R. ankle implant is encouraging, although we have encountered more complications and potential problems than previously reported.
There is no standardized method reported in the literature to measure ROM of the ankle after a total ankle arthroplasty, which limits the possibility to compare results from the various ankle designs. It seems that most of the measurements are a combination of ankle and midfoot motion, not the tibiotalar joint. A protocol was developed to accurately measure the true tibiotalar and midfoot motion before and after an ankle replacement. Lateral radiographs were taken of the ankle with the patient in a weightbearing position, and measurements were done along fixed landmarks. In this study, the tibiotalar, midfoot, and combined ROM were measured preoperative and 1 year postoperative in a standardized, reproducible fashion. The preoperative tibiotalar ROM was 18.5 degrees and combined ankle and midfoot motion 25.1 degrees. The true tibiotalar motion after an Agility total ankle arthroplasty was 23.4 degrees, and the combined ankle and midfoot motion was 31.3 degrees. The average improvement in ROM in the tibiotalar joint was approximately 5 degrees, and combined ROM was 6.1 degrees. Preoperative ROM proved to be the main factor determining the eventual postoperative ROM. It is possible to accurately measure the true ankle and the midfoot motion and those measurements should be used when reporting on the results of ankle replacements. Total ankle arthroplasty resulted in a statistically significant, but clinically less than expected, increase in ROM.
Two consecutive series of patients who had cementless, porous-coated, congruent-contact, mobile-bearing total ankle replacements were evaluated during a 20-year interval using the New Jersey Orthopaedic Hospital ankle scoring scale to determine clinical outcome and overall implant survivorship with revision as an end point. The initial series of 38 patients (40 ankle replacements) using a shallow-sulcus design had diagnoses of: osteoarthritis, seven (17.5%); rheumatoid arthritis, nine (22.5%); posttraumatic arthritis, 21 (52.5%); and failed fusion, three (7.5%). Clinical results after 2-20 years, (mean, 12 years) were 28 (70%) good to excellent, two (5%) fair, and 10 (25%) poor. Postoperative ankle motion ranged from 10 degrees-47 degrees total arc (mean, 25 degrees total arc). The 20-year overall survivorship for the shallow-sulcus design was 74.2%. A second series of 74 patients (75 ankle replacements) using a deep-sulcus design had diagnoses of: osteoarthritis, eight (11%); rheumatoid arthritis, nine (12%); osteonecrosis, three (4%); and posttraumatic arthritis, 55 (73%). Clinical results after 2-12 years, (mean 5 years) were 66 (88%) good to excellent, four (5%) fair, and five (7%) poor. Postoperative ankle motion ranged from 10 degrees-50 degrees total arc (mean, 29 degrees total arc). The 12-year overall survivorship for the deep-sulcus design was 92%.
The Salto Total Ankle Prosthesis is noncemented with mobile bearings and is characterized by an anatomic design and a dual Ti-HA coating. Between 1997 and 2000, 98 consecutive Salto prostheses were implanted. At last followup, two patients were deceased, one patient was lost to followup, and two prostheses were removed in two patients. Ninety-three implants in 91 patients were available with a mean followup of 35 months (range, 24-68 months). Survivorship at 68 months, with the end point implant removal, then was 98% (favorable scenario) to 94.9% (unfavorable scenario). The American Orthopaedic Foot and Ankle Society score was 32.3 points preoperatively and 83.1 points at followup. Seventy-two patients are pain-free, 54 patients walk unlimited distances, and 25 patients have limitation but walk more than 1 km. Sixty-seven patients have no limp but seven need walking aids. Fifty-eight patients can walk on tiptoes, 49 patients can walk on uneven ground, 14 patients can run, 76 patients ascend stairs normally, and 63 patients descend stairs normally. Range of motion as measured on stress radiographs improved from 15.2 degrees preoperatively to 28.3 degrees at followup. Preliminary results of the Salto prosthesis are encouraging and validate the concept of anatomic replacement.
Although ankle arthrodesis remains a standard operative procedure for disabling ankle arthritis, it has potential long-term problems. Total ankle arthroplasty offers preserved joint motion and may be a more favorable option in select patients. The purpose of this study was to report the intermediate-term clinical and radiographic results of total ankle arthroplasty using the Agility prosthesis.
We retrospectively reviewed the results of total ankle arthroplasty in 41 consecutive patients (43 ankles). Evaluation included preoperative and postoperative questionnaires, physical examination, and radiographs.
At the time of followup, 38 patients (40 ankles) were available for review. The most common preoperative diagnoses included posttraumatic arthritis (24 of 40 ankles, 60%) and rheumatoid arthritis (eight of 40 ankles, 20%). Average age at surgery was 63 (range 32 to 85) years. Average followup was 44.5 (range 26 to 64) months. Preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scores averaged 33.6 and 83.3, respectively, demonstrating significance (p < 0.001). Postoperative Medical Outcomes Study Short Form-36 (SF-36) Physical Component Summary (PCS) and Mental Component Summary (MCS) scores averaged 49.5 and 56.1, respectively. Although 34 of 40 ankles demonstrated radiographic lucency or lysis, the degree of involvement varied. Migration or subsidence of components was noted in 18 ankles. Overall, 37 of 38 patients were satisfied with the outcome of their surgery and would have the same procedure under similar circumstances.
Agility total ankle arthroplasty results in a favorable clinical outcome and patient satisfaction in most patients at intermediate-term followup. However, total ankle arthroplasty is associated with potential complications and the need for subsequent operative intervention. Radiographic followup commonly reveals periprosthetic lucency, lysis, and component migration or subsidence, but this does not appear to adversely affect the intermediate-term clinical outcome. The long-term consequences of such radiographic findings are of concern, and surgeons and patients choosing this procedure need to be cautious.
Interest in mobile-bearing total ankle arthroplasty has increased in recent years. However, to our knowledge, no study has focused exclusively on patients with the diagnosis of inflammatory joint disease or has provided a detailed analysis of the risk factors for failure.
A prospective observational study of the results of cementless mobile-bearing total ankle arthroplasty in patients with inflammatory joint disease (mainly rheumatoid arthritis) was conducted at two centers. Ninety-three total ankle arthroplasties were performed. The LCS (low contact stress) prosthesis was used initially, in nineteen ankles, between 1988 and 1992, and a modification of the LCS prosthesis, the Buechel-Pappas design, was used in seventy-four ankles between 1993 and 1999. Clinical and radiographic follow-up was performed at yearly intervals. Three clinical scoring systems were used, and any complication was recorded throughout follow-up. Actuarial survival (with revision as the end point), multivariate analysis, and a competing risk approach were used to describe the long-term outcome.
The clinical result at one year after surgery showed a significant improvement in the scores on all three scoring systems (p < 0.05). Ankle dorsiflexion (mean, 7 degrees ) also improved significantly (p < 0.05) compared with the preoperative state. The most frequent complication was a malleolar fracture, which occurred in twenty ankles. Only when it occurred in combination with a deformity in the frontal plane did this complication have an adverse effect on the end result. At a mean follow-up of eight years, seventeen patients (twenty-one ankles) had died and fifteen ankles had been revised because of aseptic loosening (six ankles), primary or secondary axial deformity with edge-loading (six ankles), deep infection (two ankles), and a severe wound-healing problem (one ankle), leaving fifty-seven ankles (61%) that were evaluated. The mean overall survival rate at eight years was 84%. An increased failure rate was encountered in ankles with a preoperative deformity in the frontal plane of >10 degrees (p = 0.03) and in ankles in which an undersized tibial component had been implanted (p = 0.02).
Mobile-bearing total ankle arthroplasty is a valid treatment option for the rheumatoid ankle if proper indications are used. Aseptic loosening and persistent deformity are the most important modes of failure.
Few studies have reported the intermediate to long-term results of minimally constrained total ankle replacements. The purpose of this study was to investigate the efficacy and safety of a minimally constrained total ankle prosthesis in a select low-demand patient population.
We reviewed a consecutive series of patients with rheumatoid arthritis who underwent a Buechel-Pappas total ankle replacement (BP TAR) between 1990 to 1997. Thirty-one ankle arthroplasties were performed in 23 patients with rheumatoid arthritis. One patient was lost to followup (deceased) and two ankles that failed resulted in fusion (overall survivorship - 93%). This left 28 ankles (21 patients) that were re-evaluated clinically and radiographically with an average followup of 8.3 (range 5.0 to 12.2) years. Preoperative and postoperative ranges of motion were measured and AOFAS hindfoot scores were calculated. Recent weightbearing radiographs were reviewed for evidence of component subsidence, radiolucent lines, and osteolysis.
In 25 of 28 ankles (89%), patients were completely satisfied with the result of their ankle replacement and rated their pain as only mild to none; three (11%) patients were dissatisfied. Radiographic analysis revealed stable, well-positioned implants with evidence of biologic ingrowth in 23 ankles (82%), while five implants were interpreted as being at risk for impending failure because of marked tibial or talar component subsidence (18%). Component subsidence did not correlate with the presence or absence of radiolucent lines. Only one ankle demonstrated clear evidence of osteolysis. Ten intraoperative medial malleolar fractures occurred (32% of ankles) during implantation of the prosthesis, though in only one did this adversely affect patient outcome. Nine postoperative complications (29%) occurred; four wound dehiscences, four stress fractures, and one medial malleolar nonunion.
Improvements in prosthetic design such as cementless fixation and decreased constraint appear to make total ankle arthroplasty a more predictable procedure over this period of followup. Despite a variety of complications, we are encouraged by the intermediate-term results in a select low-demand arthritic population.
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.
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.
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.
From this series we concluded that rheumatoid arthritis and use of a prosthesis larger than size 1 are predictive factors for better outcome.
Osteolysis after total ankle arthroplasty (TAA) has become a major concern regarding long-term implant survival. The primary goal of this study was to determine whether CT was more sensitive than plain films in detecting the presence and extent of periprosthetic lucency. A secondary goal was to determine whether lack of syndesmotic fusion was associated with more extensive lucency.
Seventeen patients (19 ankles) who had TAA between 2001 and 2003 were consecutively recruited and evaluated as part of a prospective study. Plain radiographs and helical CT with metal-artifact minimization were obtained. Evidence of lucent lesions and syndesmotic fusion was compared using the different imaging techniques.
Of the 19 ankles imaged, a total of 29 lesions were detected by CT, whereas plain radiographs detected 18 lesions. CT detected 21 lesions less than 200 mm(2), of which plain radiographs detected only 11. The mean size of the lesions detected on CT was over three times larger than the size on plain radiographs. With the small sample size used, there were no statistically significant differences between ankles with and without fusion of the syndesmosis and the extent (p = 0.84) and location (p = 0.377) of lucency.
CT is a more accurate method for early detection and quantification of periprosthetic lucency than plain radiographs. Accurate evaluation of lucent lesions may identify patients at high risk for lack of syndesmotic fusion with subsequent loosening and implant failure.
Forty-seven consecutive patients treated for ankle arthritis with a Scandinavian total ankle replacement (STAR) by one surgeon were investigated retrospectively.
A modification of the Foot Function Index (FFI), which scores pain and task difficulties, was followed prospectively. Patients were assessed clinically and radiologically. Failure was defined as revision of the prosthesis or arthrodesis for any reason.
In 47 patients (16 male, 31 female) 49 total ankle replacements were carried out between May 1999 and June 2004. Indication for surgery was end stage arthritis for rheumatoid arthritis in 29 cases, post-traumatic arthritis in 12, osteoarthritis in five and arthritis secondary to degenerative flatfoot in three. Mean followup time was 28 (12 to 67) months. The modified FFI (range, 0 to 100, a high score meaning more pain and disability) improved significantly from 59 before to 35 after surgery. The mean postoperative Kofoed ankle score was 68. Sixteen procedures were complicated by fractures or temporary neurological damage. At the time of followup, 45 prostheses survived, while four replacements had failed. Radiological examination at followup showed radiolucent lines, osteolysis, and malposition of the components in 31 cases.
Our results are comparable with those reported in the literature. The clinical outcome improved significantly. Due to aseptic and septic loosening, 8.2% of the prosthesis failed.