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years) complete clinical data and radiographs were available for 84 patients; 7 had incomplete data, 1 had died, 4 were withdrawn after enrolling but prior to surgery, and 4 were lost to follow-up.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 Previous studies have suggested that injury to the anterior talofibular ligament (ATFL) may be linked to altered kinematics
and the development of osteoarthritis of the ankle joint. ...However, the effects of ATFL injury on the in vivo kinematics of
the ankle joint are unclear.
Hypothesis Based on the orientation of the ATFL fibers, ATFL deficiency leads to increased anterior translation and increased internal
rotation of the talus relative to the tibia.
Study Design Descriptive laboratory study.
Methods The ankles of 9 patients with unilateral ATFL injuries were compared as they stepped onto a level surface. Kinematic measurements
were made as a function of increasing load. With use of magnetic resonance imaging and orthogonal fluoroscopy, the in vivo
kinematics of the tibiotalar joint were measured in the ATFL-deficient and intact ankles of the same individuals.
Results A statistically significant increase in internal rotation, anterior translation, and superior translation of the talus was
measured in ATFL-deficient ankles, as compared with the intact contralateral controls. For example, at 100% body weight, ATFL-deficient
ankles demonstrated an increase of 0.9 ± 0.5 mm in anterior translation ( P = .008), an increase of 5.7° ± 3.6° in internal rotation ( P = .008), and a slight increase of 0.2 ± 0.2 mm in the superior translation ( P = .02) relative to the intact contralateral ankles.
Conclusion Deficiency of the ATFL increases anterior translation, internal rotation, and superior translation of the talus.
Clinical Relevance Altered kinematics may contribute to the degenerative changes observed with chronic lateral ankle instability. These findings
might help to explain the degenerative changes frequently observed on the medial talus in patients with chronic ATFL insufficiency
and so provide a baseline for improving ankle ligament reconstructions aimed at restoring normal joint motion.
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.
The risk-benefit profiles of simultaneous total ankle arthroplasty (TAA) compared with sequential TAA continue to be debated. There are limited case series reporting outcomes after bilateral TAA, ...with no previous comparison of simultaneous TAA with sequential TAA. Patients with bilateral pathology represent a unique population with an overall more debilitating condition. Thus, we aimed to compare bilateral simultaneous and sequential TAAs, including perioperative complications and patient-reported outcome measures.
We performed a comparative cohort study of patients who underwent primary bilateral TAA, performed in a simultaneous or sequential fashion, from 2007 to 2019 at a single academic center. Data on patient demographic characteristics, comorbidities, perioperative complications, reoperations, and implant failures were collected. Patient-reported outcome measures included preoperative and postoperative visual analog scale (VAS) scores for pain, Short Form-36 Health Survey (SF-36) scores, and Short Musculoskeletal Function Assessment (SMFA) scores.
A total of 50 patients (100 ankles) were included, with 25 patients (50 ankles) each in the bilateral simultaneous and sequential cohorts. The mean follow-up was 52.2 ± 27.3 months (range, 24 to 109 months). The mean time between sequential TAAs was 17.5 ± 20.1 months (range, 3 to 74 months). The mean patient age was 64.3 ± 10.6 years (range, 21 to 76 years), and 32 (64.0%) were men. The majority of patients (28 patients 56.0%) had primary osteoarthritis. Both cohorts had equivalent preoperative patient-reported outcome measures and experienced improvements in all measures, which were maintained at the final follow-up with no significant between-group differences (all p > 0.05). There were no differences between the simultaneous TAA group and the sequential TAA group in perioperative complication rates (22.0% compared with 24.0%; p = 0.7788), reoperations (12.0% compared with 10.0%; p = 0.7354), 5-year reoperation-free survival (88.0% compared with 90.0%; p = 0.4612), or failure-free survival (100%). One patient in the simultaneous TAA cohort required metal component revision at 8 years postoperatively.
The patient-reported outcome measures, complications, and prosthesis survival of patients who underwent bilateral simultaneous TAA were comparable with those of patients who underwent bilateral sequential TAA. We advocate that simultaneous bilateral TAA is a safe and effective method for the treatment of bilateral end-stage ankle osteoarthritis.
Therapeutic 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.
PDF
