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Introduction/Purpose: Total ankle replacements (TAR) have rapidly advanced in terms of volume, technique, design, and indications. However, they are still at risk for failure and need for revision, even early in the postoperative period. Although recently there has been extensive research on TAR, many studies are limited in their power and sample size to assess risk factors for failure/revision. Using a large multi-surgeon retrospective database, we sought to describe the incidence and etiology of mechanical failure across modern implants. We also aimed to identify risk factors for early mechanical failure. We hypothesized that greater body mass index (BMI) and ipsilateral hindfoot fusion would be predictors of mechanical failure, and that implants with greater extent of tibial fixation (stems and keels) would be protective against mechanical failure. Methods: This is a single-center retrospective review of TAR patients in a prospective database. Adults undergoing primary TAR using any implant (Cadence, Inbone, Infinity, Invision, Salto, STAR, Vantage, Zimmer) who were minimum 2 years post-surgery were included. Exclusion criteria included revision TAR or patients undergoing ankle fusion takedown and conversion to TAR. Five surgeons contributed patients. Demographics, etiology of arthritis, operative data, and postoperative complications, reoperations, and revisions were collected. Revisions and reoperations were classified by standard criteria. Cause of revision was recorded. There were 560 TARs eligible for 2-year follow-up (mean 3.9 +- 1.1 years postoperative), with mean follow-up of 2.2 +- 1.4 years (range 1-71 months). The cohort had mean age 63.8 +- 9.1 years, BMI 29.4 +- 5.2 kg/m2, and 57% were male. Kaplan- Meier survival plots were created. Risk factors for revision due to mechanical failure were analyzed using multivariable logistic regression with partial Wald chi square statistics. Results: Most implants were low-profile (n=444, 79.3%), with 28 implants having tibial keels (5%) and 88 with tibial/talar stems (15.7%). There were 25 (4.5%) revisions of tibial and/or talar components at mean 1.6 years after index surgery (Figure). Preoperative coronal deformity did not impact revision rates (p=0.433). Patients who underwent revision for mechanical failure had significantly higher rates of concomitant hindfoot fusion (20% vs. 8.4%, p=0.047) and greater BMI (31.4 kg/m2 vs. 29.3 kg/m2, p=0.04). In multivariable logistic regression, hindfoot fusion was just short of statistical significance (odds ratio [OR] 2.96, p=0.056), and BMI was not significant (OR 1.05, p=0.417). Stemmed or keeled implants did not significantly decrease revision rates compared to low-profile implants, although the revision rate of stemmed implants was substantially low (1/88, 1.1%). Conclusion: Among 560 modern TAR implants, short-term survivorship was 95% at 2-year follow-up, which is consistent with existing studies. Patients who underwent revision for early mechanical failure had significantly higher BMI and rates of hindfoot arthrodesis. However, these variables fell short of statistical significance in multivariable regression, suggesting that there are either additional factors contributing to revision, or a larger cohort is needed. In addition, these results are likely biased by surgeons' tendencies to use stemmed implants in patients with hindfoot fusions. Further research is warranted to determine if stemmed implants provide a protective effect in these high-risk patients. [ABSTRACT FROM AUTHOR]

Introduction/Purpose: Hallux valgus (HV) is recognized as a triplanar deformity comprising axial abduction, sagittal hypermobility, and coronal pronation of the first metatarsal. A first tarsometatarsal (TMT) arthrodesis may be used to address all three planes of deformity. The Lapiplasty system (Treace Medical Concepts, Inc., Ponte Vedra, FL) was developed to reproducibly address triplanar deformity. However, the Lapiplasty system is costlier than other fixation constructs. Because healthcare is increasingly value-focused, we sought to determine if the more expensive Lapiplasty system improved radiographic outcomes or decreased complication rates over standard cross-screw fixation. We hypothesized that HV patients undergoing first TMT arthrodesis with the Lapiplasty system would have equivalent radiographic correction and similar complication rates when compared to patients treated with cross-screw fixation. Methods: In this multi-center, IRB-approved retrospective study, consecutive series of patients who underwent 1st TMT arthrodesis for HV, either with cross-screw fixation at Institution A, or Lapiplasty at Institution B, were identified by registry search. Inclusion criteria included age over 18 and preoperative and minimum 6-month postoperative weight-bearing AP and lateral radiographs. Exclusion criteria included primary conditions other than hallux valgus and previous first ray surgeries or ipsilateral arthrodeses. Hallux valgus angle (HVA), intermetatarsal angle (IMA), and tibial sesamoid position (TSP) were measured preoperatively and at final follow-up, and clinic notes were reviewed to identify complications and reoperations. To compare cohorts, Mann-Whitney U tests and Fisher's Exact tests were applied for continuous and discrete variables, respectively. To examine preoperative-postoperative changes, Wilcoxon signed rank tests were used. Multivariable regressions tested the effect of fixation constructs on postoperative radiographic parameters, adjusted for preoperative radiographic measurements, age, sex, and BMI. Results: 65 patients were included in each group, with 121 (93.8%) female patients, mean (SD) age 54.7 (14.8), BMI 25.8 (5.2), and radiographic follow-up time 8.9 (6.7) months. The Lapiplasty cohort had greater BMI (26.8 vs. 24.7, P = .048), and there were no significant differences between groups in age, sex distribution, and radiographic follow-up time. Radiographic measurement data is displayed in Table 1. After adjusting for age, sex, BMI, preoperative HVA, and preoperative IMA, fixation with Lapiplasty was significantly associated with lower postoperative IMA (b=-2.03, 95% CI = [-2.78, -1.37], P < .001) and lower postoperative HVA (b= -7.48; 95% CI = [-9.69, -5.26]; P < .001), but not postoperative sesamoid position. There were no significant differences between cohorts in the incidence of complications or reoperations. Conclusion: We found that use of the Lapiplasty system was associated with better radiographic hallux valgus correction, as evidenced by lower postoperative HVAs and IMAs, compared to standard technique with crossing screws. The clinical significance of these findings is unclear, as complication and reoperation rates were similar between groups. Future research assessing longer-term outcomes, patient-reported outcome data, and cost-benefit analysis will be necessary to further compare techniques and fixation systems. [ABSTRACT FROM AUTHOR]