Outcomes of Total Ankle Replacement with Preoperative Varus Deformity.

Historically, coronal plane deformities of greater than 10° to 15° have been deemed contraindications for total ankle replacement (TAR). However, recent studies show satisfactory results in TAR with severe preoperative varus deformity. When correctly applying ancillary procedures, preoperative varus deformity can be structurally corrected, resulting in similar clinical scores to those obtained with "regular TAR." However, complications and revisions appear to increase with increasing deformity. Unfortunately, results of TAR in varus ankles consist of heterogeneous data (eg, with regards to prosthetic brands, bearing-types, duration of follow-up, and ancillary procedures) precluding strict conclusions. This could be solved by an international consensus group.

Long-term Follow-up of 254 Ceramic Coated Implant (CCI) Evolution Total Ankle Replacements.

BACKGROUND: The ceramic coated implant (CCI) Evolution was a third-generation implant design used in approximately 2000 total ankle replacements (TARs) between 2003 and 2016. Because this implant was abandoned, long-term follow-up studies are lacking. METHODS: All patients undergoing TAR using a CCI prosthesis between 2004 and 2012 were included for analysis. Preoperatively the tibiotalar alignment was measured, and postoperatively the patients were followed up clinically, with radiographs and by questionnaire. The primary outcome was implant survival at 10 years of follow-up. Implant survival was also compared for (1) inflammatory joint disease vs noninflammatory joint disease and (2) preoperative tibiotalar neutral vs varus or valgus alignment. The secondary outcomes were complications, reoperations, and function (assessed by patient-reported outcome measures). RESULTS: Two hundred fifty-four TARs were performed in 237 patients. Two hundred twelve additional procedures were performed to achieve stable ankles. At 10-year follow-up, the survival was 67.5%, with an average time to revision of 4.5 years. The 10-year survival of the inflammatory joint disease group was 76.8% and of the noninflammatory joint group 63.1% (P = .44). In 248 TARs, the preoperative tibiotalar alignment was measured; (62% neutral, 25% varus, and 13% valgus), these showed 10-year survival rates of 74.7%, 48.2%, and 68.9% respectively (P = .07). The complication rate was 54%; 37% of patients underwent reoperation. At a mean of 8.5 years, postoperative satisfaction scored an average of 7.0 (SD 2.26) on a 0- to 10-point numeric rating scale. The mean Foot and Ankle Ability Measure sports subscore was 24.7, the mean Foot and Ankle Outcome Score (FAOS) sports subscore was 42.8, and the mean 36-Item Short Form Health Survey score was 40.0. Regarding daily activities, the mean FAOS was 81.0. CONCLUSION: This is currently the sole study reporting the long-term results of the CCI prosthesis. The survival and functional outcomes were inferior to other third-generation mobile-bearing ankle implants.

Medial malleolar osteotomy for the correction of tibiotalar varus deformity during total ankle arthroplasty: Results in 95 ankles.

BACKGROUND: The importance of deformity correction before or during total ankle replacement (TAR) has been recognized for a long time. Our results of TAR, combined with medial malleolar lengthening osteotomy, for the reconstruction of osteoarthritic ankles with varus deformity are hereby reported. METHODS: All ankles in which a medial malleolar osteotomy was performed during implantation of an ankle prosthesis during the period 1998-2018 were filtered out of our database. Preoperative coronal talar alignment was evaluated by measuring the angle between the tibial shaft and talar dome on the weightbearing mortise ankle radiograph. Patient-reported outcomes were measured with the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Ability Measure (FAAM). A Kaplan-Meier survival curve was constructed and the number of revisions per 100 observed component years was calculated for interprosthetic comparison. RESULTS: A total of 95 TARs were included, consisting of the Alpha Ankle Arthroplasty (n = 22); Buechel-Pappas (n = 14) and the Ceramic Coated Implant Evolution (n = 59) prostheses. The preoperative average talar angle in these ankles was 12.4 degrees varus. In 33% (31/95) corrective procedures, in addition to the medial malleolar osteotomy, were performed. A reoperation rate of 44% (42/95) was found, including 28 revisions (revision rate 29% (4% septic; 25% aseptic) at an average follow-up of 5.9 years, resulting in a survival of 0.69 for the total cohort at 10 years of follow-up. At an average follow-up of 6.6 years the average FAOS scores were: FAOSsymptoms 66, FAOSpain 73, FAOSfunction 78, FAOSsport 45 and FAOSquality of life 56 respectively. The FAAMadl score averaged 64. CONCLUSION: This is the largest cohort of TAR combined with medial malleolar osteotomy to date. A 29% revision rate at 5.9 years of average follow-up compares unfavorably with regular cohort studies and with most other results in varus-deformed ankles. Scores on the FAOS and FAAM are comparable to those obtained in regular cohorts with similar length of follow-up. TAR in varus-deformed ankles necessitating medial malleolar osteotomy has an even higher failure rate than regular TAR. Obtaining a stable prosthesis with a neutrally-aligned hindfoot at the end of the procedure is of paramount importance. LEVEL OF EVIDENCE: IV.

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

BACKGROUND: The National Institute for Health and Care Excellence criterion for hip replacements is a (projected) revision rate of less than 5% after 10 years. No such criterion is available for ankle prostheses. The objective of the current study is to compare survival rates of contemporary primary ankle prostheses to the hip-benchmark. METHODS: The PRISMA methodology was used. Eligible for inclusion were clinical studies reporting revision rates of currently available primary total ankle prostheses. Data was extracted using preconstructed forms. The total and prosthesis-specific annual revision rate was calculated. RESULTS: Fifty-seven articles of eight different ankle prostheses were included (n = 5371), totaling 513 revisions at an average 4.6 years of follow-up. An annual revision rate of 2.2 was found (i.e. an expected revision rate of 22% at 10 years). CONCLUSIONS: The expected 10-year revision rate of contemporary ankle prostheses is lower than the current benchmark for hip prostheses.

Patient selection for total ankle arthroplasty.

Total ankle arthroplasty is a treatment option for end-stage osteoarthritis of the ankle, as is ankle arthrodesis. Many variables, including patient characteristics, are thought to influence clinical outcome and survival. As with any surgery, but especially with total ankle replacement (TAR), patient selection is considered critical for good (long-term) outcome. In this review, we summarize the available scientific evidence regarding patient characteristics and its influence on the results of TAR.

Hind- and Midfoot Motion After Ankle Arthrodesis.

BACKGROUND: After ankle arthrodesis (AA), compensatory increased range of motion in adjacent joints might lead to increased osteoarthritis. Evaluation of patient-reported outcomes after AA with validated questionnaires is rare. Likewise, reliable radiographic analysis of the position of the AA, expected to influence the range of motion of the hind- and midfoot, is lacking. Therefore, the current study was performed. METHODS: Seventeen patients with unilateral AA were included. Sagittal hind- and midfoot range of motion was measured radiographically. The position of the AA in the sagittal and coronal planes and osteoarthritis of adjacent joints were also evaluated radiographically. Measurements were compared to the contralateral side. Patient-reported outcomes via validated questionnaires were compared to a control group (n = 18). RESULTS: Average follow-up was 3.5 years. Mean combined hind- and midfoot sagittal range of motion after AA equaled that of the contralateral side (20.8 vs. 21.0 degrees; P = .93). The tibiotalar angle after AA equaled that of the contralateral side (107 vs. 107 degrees; P = .86). The talus was translated posteriorly after AA (T-T ratio 0.45 vs. 0.34; P < .001). Low intraclass correlation coefficients (ICC) precluded reliable evaluation of the coronal position of the hindfoot (ICC, 0.07 and -0.34) and osteoarthritis in adjacent joints (ICC range, 0-0.54). SF-36 physical health scores after AA are lower as compared with those of controls (50 vs. 56; P = .01). Scores on the Foot and Ankle Outcome Score and Ankle Osteoarthritis Scale were also significantly lower. Patient satisfaction with AA was high (average visual analog scale score, 83). CONCLUSION: No increased sagittal range of motion in the hind- and midfoot after AA was found at 3.5 years of follow-up as compared with the contralateral side. Tibiotalar angles were equal. The talus was translated posteriorly. The hindfoot alignment view was not suitable to analyze the position of the hindfoot. Low ICC of the Kellgren and Lawrence scale precluded evaluation of osteoarthritis of adjacent joints. Patients scored lower than controls on self-reported outcome questionnaires but were satisfied with the result of AA.

Medial malleolar osteotomy for the correction of varus deformity during total ankle arthroplasty: results in 15 ankles.

BACKGROUND: 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. MATERIALS AND METHODS: 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. RESULTS: 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). CONCLUSION: 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.