Background:
Outcomes of total ankle replacement for the treatment of end-stage ankle arthritis continue to improve. Debate continues whether a mobile-bearing total ankle replacement (MB-TAR) or a ...fixed-bearing total ankle replacement (FB-TAR) is superior, with successful outcomes reported long term for MB-TAR and at intermediate- to long-term follow-up for newer generation FB-TAR. Although comparisons between the 2 total ankle designs have been reported, to our knowledge, no investigation has compared the 2 designs with a high level of evidence. This prospective, randomized controlled trial conducted at a single institution compares patient satisfaction, functional outcomes, and radiographic results of the mobile-bearing STAR and the fixed-bearing Salto-Talaris in the treatment of end-stage ankle arthritis.
Methods:
Between November 2011 and November 2014, adult patients with end-stage ankle osteoarthritis failing nonoperative treatment were introduced to the study. With informed consent, 100 patients (31 male and 69 female, average age 65 years, range 35-85 years) were enrolled; a demographic comparison between the 2 cohorts was similar. Exclusion criteria included inflammatory arthropathy, neuropathy, weight exceeding 250 pounds, radiographic coronal plane deformity greater than 15 degrees, or extensive talar dome wear pattern (“flat-top talus”). Prospective patient-reported outcomes, physical examination, and standardized weightbearing ankle radiographs were obtained preoperatively, at 6 and 12 months postoperatively, and then at yearly intervals. Data collection included visual analog pain score, Short Form 36, Foot and Ankle Disability Index, Short Musculoskeletal Functional Assessment, and American Orthopaedic Foot & Ankle Society ankle-hindfoot score. Surgeries were performed by a nondesign team of orthopedic foot and ankle specialists with total ankle replacement expertise. Statistical analysis was performed by a qualified statistician. At average follow-up of 4.5 years (range, 2-6 years) complete clinical data and radiographs were available for 84 patients; 7 had incomplete data, 1 had died, 4 were withdrawn after enrolling but prior to surgery, and 4 were lost to follow-up.
Results:
In all outcome measures, the entire cohort demonstrated statistically significant improvements from preoperative evaluation to most recent follow-up with no statistically significant difference between the 2 groups. Radiographically, tibial lucency/cyst formation was 26.8% and 20.9% for MB-TAR and FB-TAR, respectively. Tibial settling/subsidence occurred in 7.3% of MB-TAR. Talar lucency/cyst formation occurred in 24.3% and 2.0% of MB-TAR and FB-TAR, respectively. Talar subsidence was observed in 21.9% and 2.0% of MB-TAR and FH-TAR, respectively. Reoperations were performed in 8 MB-TARs and 3 FH-TARs, with the majority of procedures being to relieve impingement or treat cysts and not to revise or remove metal implants.
Conclusion:
With a high level of evidence, our study found that patient-reported and clinical outcomes were favorable for both designs and that there was no significant difference in clinical improvement between the 2 implants. The incidence of lucency/cyst formation was similar for MB-TAR and FH-TAR for the tibial component, but the MB-TAR had greater talar lucency/cyst formation and tibial and talar subsidence. As has been suggested in previous studies, clinical outcomes do not necessarily correlate with radiographic findings. Reoperations were more common for MB-TAR and, in most cases, were to relieve impingement or treat cysts rather than revise or remove metal implants.
Level of Evidence:
Level I, prospective randomized study.
Background:
As the popularity of total ankle arthroplasty (TAA) increases and indications expand, surgeons require a better understanding of which patient factors are associated with implant failure. ...In this study, we aimed to use a large total ankle database to identify independent risk factors for implant failure at mid- to long-term follow-up.
Methods:
A prospectively collected database was used to identify all patients who underwent primary TAA with a minimum 5 years’ follow-up. The primary outcome was revision, defined as removal of one or both metal components; failures due to infection were excluded. Patient and clinical factors analyzed included age, sex, body mass index (BMI), smoking status, presence of diabetes, indication for TAA, implant, tourniquet time, and presence of ipsilateral hindfoot fusion. Preoperative coronal deformity and sagittal talar translation were assessed, as were postoperative coronal and sagittal tibial component alignment. Univariable and multivariable analyses were performed to identify predictors of implant failure. After excluding 5 ankles that failed because of deep infection, 533 ankles with a mean 7 (range, 5-11) years of follow-up met the inclusion criteria. Four implants were used: INBONE I, INBONE II, STAR, and Salto-Talaris.
Results:
Thirty-four ankles (6.4%) were revised or removed a mean 4 (range, 1-9) years postoperatively. The only independent predictors of failure were the INBONE I prosthesis and ipsilateral hindfoot fusion (P = .006 and P = .023, respectively).
Conclusions:
This is among the largest studies to analyze the relationship between TAA failure rates and multiple different patient, operative, and radiographic factors. Of note, age, BMI, and amount of deformity were not associated with higher failure rates. Only patients with ipsilateral hindfoot fusion or who received the INBONE I prosthesis were at significantly higher risk of implant failure.
Level of Evidence:
Level III, retrospective cohort study.
Background:
Wound complications following total ankle replacement (TAR) potentially lead to devastating consequences. The aim of this study was to compare the operative and demographic differences in ...patients with and without major wound problems which required operative management. We hypothesized that increased tourniquet and operative time would negatively influence wound healing.
Methods:
We identified a consecutive series of 762 primary TARs performed between December 1999 and April 2014 whose data were prospectively collected. We then identified the subset of patients who required a secondary surgery to treat major wound complications (ie, operative debridement, split-thickness skin grafting, and soft tissue reconstruction). All patients requiring a second surgery had operative wound debridement. We then compared the demographics, operative characteristics, and functional scores to see if any differences existed between patients with and without major wound complications. Clinical outcomes including secondary procedures and implant failure rates were recorded.
Results:
Twenty-six patients (3.4%) had a total of 49 operative procedures to treat major wound issues. Eighteen patients had flaps and 14 had split-thickness skin grafts. The median time to operatively treating the wound was 1.9 (range: 0.5-12.5) months after the index TAR. The median follow-up time from the wound procedure was 12.7 (range: 1.2-170.8) months. Compared to the control group, patients with major wounds had a significantly longer mean surgery (214.8 vs 189.3 minutes, P = .041) time and trended toward a longer median tourniquet time (151 vs 141 minutes, P = .060). Patients without wound complications were more likely to have posttraumatic arthritis, whereas those with wound complications were more likely to have primary osteoarthritis (P = .006). The control group trended toward having a higher mean BMI (29.5 vs 27.2, P = .056). There were 6 failures in the major wound complication cohort (23.1%), including 2 below the knee amputations.
Conclusion:
Ankle wounds that required operative management had high failure rates and some resulted in devastating outcomes. We did not find any increase in major wound complications in those with various risk factors as identified by other studies. Given our data, we recommend limiting operative time. While correcting hindfoot and midfoot alignment is important for improving patient functionality and survivorship of the implant, thought should be given to staging the TAR if multiple pathologies are to be addressed at the time of surgery to limit operative time.
Level of Evidence:
Level III, retrospective comparative series.
Background:
Studies examining the clinical outcomes of revision total ankle arthroplasty (TAA) are sparse. Revision TAA surgery has become more common with availability of revision implants and ...refinement of bone-conserving primary implants. In this study, patient-reported results and clinical outcomes were analyzed for a cohort of patients who underwent both primary and revision TAA at a single high-volume institution.
Methods:
We retrospectively reviewed prospectively collected data on 29 patients with failed primary total ankle arthroplasty. Cases of isolated polyethylene exchange, infection, or extra-articular realignment procedures were excluded. Patient-reported outcome (PRO) measures and clinical results were reviewed in this longitudinal study.
Results:
Fifteen patients (51.7%) underwent revision of just the talar and polyethylene components while 13 patients (44.8%) underwent revision of all components. The most common cause was talar subsidence (51.7%). The average time to revision was 3.9 years with a follow-up of 3.2 years after revision, and 3 (10.3%) revision arthroplasties required further surgery; 2 required conversion to arthrodesis and 1 required second revision TAA. Improvements in PROs were better after primary than revision TAA.
Conclusions:
Clinical and patient-reported results of revision ankle arthroplasty after metal component failure improved significantly but never reached the improvements seen after primary ankle arthroplasty. In our series, 10.3% of revision TAAs required a second revision TAA or arthrodesis surgery.
Levels of Evidence:
Therapeutic Level III, comparative series.
The design of total ankle arthroplasty systems is evolving as a result of findings from longer-term studies. Our understanding of modes of failure has increased, and surgical techniques have become ...more refined. Currently, five total ankle arthroplasty systems are used in the United States. The landscape has changed considerably in the decade since the latest article reviewing total ankle design was published. Some implants with acceptable intermediate results had much poorer outcomes at 7- to 10-year follow-up. As more research showing mid- to long-term outcomes is published, the design rationale and current outcomes data for each of these implants must be considered.
Background:
Tobacco use is a known risk factor for increased perioperative complications and having worse functional outcomes in many orthopedic procedures. To date, no study has elucidated the ...effect of cigarette smoking on complications or functional outcome scores after total ankle replacement (TAR).
Methods:
We retrospectively reviewed the records of 642 patients who had TAR between June 2007 and February 2014 with a known smoking status. These patients were separated into 3 groups based on their smoking status: 34 current smokers, 249 former smokers, and 359 nonsmokers. Outcome scores and perioperative complications, which included infection, wound complications, revision surgeries, and nonrevision surgeries were compared between the groups.
Results:
When comparing perioperative complications in the active smokers to the nonsmokers, we found a statistically significant increased risk of wound breakdown (hazard ratio HR 3.08, P = .047). Although the active smokers had an increased rate of infection (HR 2.61, P = .392), revision surgery (HR 1.75, P = .470), and nonrevision surgery (HR 1.69, P = .172), these findings were not statistically significant. With regard to outcome scores, all groups demonstrated improvement at 1- and 2-year follow-up compared with their preoperative outcome scores. However, the active smokers had less improvement in their outcome scores than the nonsmokers at 1- and 2-year follow-up. Furthermore, there was no significant difference in the outcome scores when comparing the nonsmokers to the former smokers.
Conclusion:
Active cigarette smokers undergoing TAR had a significantly higher risk of wound complications and worse outcome scores compared with nonsmokers and former smokers. Furthermore, tobacco cessation appeared to reverse the effects of smoking, which allowed TAR to be an effective and safe procedure for providing pain relief and improving function in former smokers as they had perioperative complication rates and outcomes similar to nonsmokers.
Level of Evidence:
Level III, retrospective comparative series.
Background Conversion of ankle arthrodesis to total ankle arthroplasty remains controversial. Although satisfactory outcomes have been published, not all foot and ankle surgeons performing total ...ankle arthroplasty have embraced this modality. Methods Twenty-three total ankle arthroplasties were performed in patients who had undergone a prior or an attempted ankle arthrodesis. The mean age at surgery was fifty-nine years (range, forty-one to eighty years), and the mean duration of follow-up was 33.1 months (minimum, twelve months). Indications for the procedure were symptomatic adjacent hindfoot arthritis (twelve patients) or symptomatic tibiotalar or subtalar nonunion (eleven) after tibiotalocalcaneal arthrodesis. We performed concomitant surgical procedures in eighteen ankles (78%), with the most common procedure being prophylactic malleolar fixation (70%). We prospectively evaluated clinical outcomes using the Short Form-36 (SF-36), Short Musculoskeletal Function Assessment (SMFA), and visual analog scale (VAS) for pain and assessed initial weight-bearing radiographs and those made at the most recent follow-up evaluation. Results The mean VAS pain score (and standard deviation) improved from 65.7 ± 21.8 preoperatively to 18.3 ± 17.6 at the most recent follow-up evaluation (p < 0.001), with five patients being pain-free (VAS score = 0). The mean SMFA bother and function indexes improved from 55 ± 22.9 and 46.7 ± 12.6 preoperatively to 30.6 ± 22.7 and 25.4 ± 17.4 at the most recent follow-up visit (p = 0.001 and p < 0.001, respectively). The mean SF-36 total score improved from 37.7 ± 19.3 to 56.4 ± 23.1 (p = 0.002). The implant survival rate was 87%. Four (20%) of the tibial components and fourteen (70%) of the talar components that were not revised exhibited initial settling and then were seen to be stabilized radiographically without further change in implant position. Three total ankle replacements (13%) showed progressive talar subsidence, prompting revision. Ten patients (43%) had minor complications not requiring repeat surgery. Conclusions Short-term follow-up after conversion of ankle arthrodesis to total ankle arthroplasty demonstrated pain relief and improved function in a majority of patients. Patients who undergo this surgery frequently require concomitant procedures; we recommend prophylactic malleolar fixation when performing conversion total ankle arthroplasty. The rate of complications, particularly talar component settling and migration, is cause for concern. We do not recommend the procedure for ankle arthrodeses that included distal fibulectomy. Level of Evidence Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Although many patients with posttraumatic ankle arthritis are of a younger age, studies evaluating the impact of age on outcomes of primary total ankle arthroplasty (TAA) have revealed heterogenous ...results. The purpose of the present study was to determine the effect of age on complication rates and patient-reported outcomes after TAA.
We retrospectively reviewed the records of 1,115 patients who had undergone primary TAA. The patients were divided into 3 age cohorts: <55 years (n = 196), 55 to 70 years (n = 657), and >70 years (n = 262). Demographic characteristics, intraoperative variables, postoperative complications, and patient-reported outcome measures were compared among groups with use of univariable analyses. Competing-risk regression analysis with adjustment for patient and implant characteristics was performed to assess the risk of implant failure by age group. The mean duration of follow-up was 5.6 years.
Compared with the patients who were 55 to 70 years of age and >70 years of age, those who were <55 years of age had the highest rates of any reoperation (19.9%, 11.7%, and 6.5% for the <55, 55 to 70, and >70-year age groups, respectively; p < 0.001), implant failure (5.6%, 2.9%, and 1.1% for the <55, 55 to 70, and >70-year age groups, respectively; p = 0.019), and polyethylene exchange (7.7%, 4.3%, and 2.3% for the <55, 55 to 70, and >70-year age groups, respectively; p = 0.021). Competing-risk regression revealed a decreased risk of implant failure for patients who were >70 of age compared with those who were <55 years of age (hazard ratio HR, 0.21 95% confidence interval (CI), 0.05 to 0.80; p = 0.023) and for patients who were 55 to 70 years of age compared with those who were <55 years of age (HR, 0.35 95% CI, 0.16 to 0.77; p = 0.009). For all subscales of the Foot and Ankle Outcome Score (FAOS) measure except activities of daily living, patients who were <55 years of age reported the lowest (worst) mean preoperative and postoperative scores compared with those who were 55 to 70 years of age and >70 years of age (p ≤ 0.001). Patients who were <55 years of age had the highest mean numerical pain score at the time of the latest follow-up (23.6, 14.4, 12.9 for the <55, 55 to 70, and >70-year age groups, respectively; p < 0.001).
Studies involving large sample sizes with intermediate to long-term follow-up are critical to reveal age-related impacts on outcomes after TAA. In the present study, which we believe to be the largest single-institution series to date evaluating the effect of age on outcomes after TAA, younger patients had higher rates of complications and implant failure and fared worse on patient-reported outcome measures.
Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
Background:
A number of new 2-component total ankle arthroplasty systems that emphasize minimal bone resection have been introduced for which few clinical outcomes reports are available. Our aim was ...to identify the rate of early revision among patients receiving the 2-component INFINITY prosthesis.
Methods:
Patients from 2 prospectively collected databases at the authors’ institution were screened for inclusion in the present study. All patients who underwent a primary total ankle arthroplasty (TAA) with the INFINITY prosthesis and who were at least 1 year postoperative were included. A total of 159 ankles with a mean 20 months of follow up (range, 12-37) met these criteria. All surgeries were performed by 1 of 2 orthopedic foot and ankle surgeons with extensive experience in TAA. The primary outcome was the need for revision surgery, defined as removal of 1 or both metal components. Peri-implant lucency at most recent follow-up was a secondary outcome. Weightbearing radiographs at most recent follow-up were graded for lucency independently by 2 reviewers.
Results:
Sixteen ankles (10%) underwent revision at a mean 13 months postoperatively. The most common reasons for revision were symptomatic tibial component loosening and deep infection (6 patients each, 3.8%). Of the 108 ankles with retained components and at least 1 year of radiographic follow-up, 8 (7.4%) had global lucency around the tibial component suggestive of loosening at most recent follow-up.
Conclusions:
Our initial review of patients undergoing TAA with this new 2-component prosthesis demonstrates an elevated early revision rate due to tibial component loosening compared to other implant systems.
Level of Evidence:
Level IV, case series.
BACKGROUND:Total ankle arthroplasty has shown durable improvements in patient-reported outcomes. However, the impact of common comorbidities and patient factors has not been fully characterized. The ...purpose of this study was to identify patient comorbidities and characteristics that impact outcomes after total ankle arthroplasty.
METHODS:Patients who underwent a total ankle arthroplasty between January 2007 and December 2016 were enrolled into a prospective study at a single academic center. Patients completed outcome measures before the surgical procedure and at the time of follow-upa visual analog scale (VAS) for pain, the 36-item Short Form Survey (SF-36), and the Short Musculoskeletal Function Assessment (SMFA). Patient and operative factors, along with prevalent preoperative comorbidities, were analyzed for association with preoperative to postoperative changes in 1 to 2-year and minimum 5-year outcomes. Comorbidities that met a significance threshold of p < 0.05 in adjusted analyses were incorporated into multivariable outcome models.
RESULTS:A total of 668 patients with a mean 1 to 2-year follow-up (and standard deviation) of 1.6 ± 0.5 years (range, 10 months to 2 years and 2 months) were included. Patients’ pain and function significantly improved across all outcomes (p < 0.05). However, depression, staged bilateral ankle arthroplasty, increased length of stay, a prior surgical procedure, increased American Society of Anesthesiologists (ASA) score, and particular implant types were associated with significantly smaller improvements in at least 1 patient-reported outcome after total ankle arthroplasty in the 1 to 2-year follow-up, although the effects were relatively small. At a minimum 5-year follow-up, smoking, depression, implant type, and staged bilateral ankle arthroplasty were associated with worse outcomes, and a prior surgical procedure, a simultaneous bilateral surgical procedure, and obesity were associated with improved outcomes.
CONCLUSIONS:Patients who underwent total ankle arthroplasty had significant improvement in patient-reported outcomes, although several factors were associated with a small, but significant, negative impact on improvement, including depression, increased ASA score, current smoking, increased length of stay, a prior surgical procedure, and staged bilateral total ankle arthroplasty. Current smoking, obesity, and depression are potentially modifiable risk factors that could be improved prior to total ankle arthroplasty. Patients with these characteristics should be counseled on their risk of limited improvement in ankle pain and disability after total ankle arthroplasty.
LEVEL OF EVIDENCE:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
PDF
