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Introduction: Patient-specific instrumentation (PSI) has been developed for total ankle arthroplasty (TAA), with proven benefits. One concern regarding PSI is the need for more soft tissue dissection in order to accurately position the PSI guides, which has the theoretical disadvantage of increased osteolysis. The purpose of our study is to compare the incidence and magnitude of osteolysis for the INFINITY Total Ankle System between PSI and standard referencing (SR) techniques. Methods: Sixty-seven patients who underwent primary TAA using Prophecy (PSI) or SR technique between 2013 and 2015 were reviewed in a retrospective observational study. Osteolysis was assessed on radiographs at 2 years. The incidence was calculated by binomial distribution. The number of zones compromised and the magnitude of osteolysis was calculated using the median as a summary statistic and interquartile range as dispersion statistic. Fisher exact test was used to compare both groups, then a regression model was estimated to calculate the odds ratio for osteolysis. Results: Of the 67 TAAs, 51 were in the PSI group and 16 in the SR group. In the PSI group the incidence, number of compromised zones (CZ), and magnitude was 41% (25%-59%), 1 [1-2], and 2 [2-3], respectively. In the SR group these were 36% (13%-65%), 3 [2-3], and 3 [2-4], respectively. No significant differences were found ( P = .46, P = .12, P = .33). A slightly higher risk of osteolysis was found in the PSI group (odds ratio = 1.33 [0.36-4.83]) ( P = .46). The majority of lesions were in 1 zone with size of 2 to 5 mm (63% for all cohort, 64% PSI, 60% SR). Two cases underwent revision for aseptic loosening, 1 in the SR group and 1 in the PSI group. Conclusion: According to our data, there is no significant difference between PSI and SR in terms of risk, incidence, size and magnitude of osteolysis in the INFINITY Total Ankle System at 2 years. Levels of Evidence: Therapeutic, Level III, Retrospective cohort study.

Background: The literature analyzing total ankle replacement (TAR) results should be critically interpreted because studies made by the design surgeons are potentially subject to bias. European nondesigner surgeon studies reviewing the HINTEGRA TAR system are scarce in the literature. The present study is a European nondesigner surgeon study reviewing a consecutive series of 50 HINTEGRA TAR systems with a minimum follow-up of 2 years, focusing on clinical and radiographic outcomes., Methods: Fifty primary TAR procedures were performed between February 2008 and January 2012 by a single surgeon. Every patient underwent a standardized clinical and radiographic follow-up at 6 weeks, 3 and 6 months, and 1 year postoperatively and annually thereafter. The mean time to final follow-up was 45 months., Results: The mean American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale score significantly increased from 43.5 preoperatively to 83.8 postoperatively. Clinical range of motion of the ankle also improved from 23.3 degrees preoperatively to 28.3 degrees postoperatively. In 70% of the TAR procedures, the talar component was positioned anteriorly with respect to the tibial axis. Radiological evidence of osteolysis was identified in 24 ankles. The failure rate in the present series was 10%, which was defined as having major revision surgery within 4 years., Conclusion: The survival of the first 50 HINTEGRA TAR systems in this series was satisfactory from clinical and radiological points of view. However, the incidence of asymptomatic periprosthetic osteolytic lesions was quite high (24 ankles)., Level of Evidence: Level IV, retrospective case series., (© The Author(s) 2014.)

Background: Periprosthetic osteolysis in total ankle arthroplasty (TAA) is a substantial problem. We report the incidence and characteristics of periprosthetic osteolysis and its association with clinical outcomes after TAA using the HINTEGRA ankle system., Methods: Between May 2004 and April 2010, 126 primary TAA were performed on 115 patients. We excluded 27 ankles with a follow-up of less than 24 months; thus, 99 ankles in 90 patients with a mean follow-up of 40.8 (range, 24-89) months were included in the study. Pain and clinical outcomes were assessed using the visual analog scale and the American Orthopaedic Foot and Ankle Society score. Fluoroscopy was used for optimum visualization of the bone-implant interfaces on radiographs. Computed tomography (CT) was conducted on 25 ankles that exhibited progression of osteolysis., Results: Radiographs revealed that 37 of the 99 ankles showed radiologic evidence of osteolysis; of these, 10 demonstrated continuous progression over the study period. Helical CT scans were more accurate than radiographs for identifying and measuring periprosthetic osteolysis in TAA. None of the demographic parameters were substantially different between the 2 groups of subjects (with or without osteolysis). No major association was found between the presence of osteolysis and clinical and radiologic outcomes., Conclusion: Osteolysis associated with TAA may indeed be common in the postoperative period. Although most of the osteolytic lesions observed here were relatively quiescent, these lesions raise concerns in contemporary TAA because of their incidence rate and the potential for later mechanical failure as compared to arthrodesis. Early diagnosis and careful evaluation of osteolysis may provide a clinical opportunity for limited revision surgery in ankles of impending prosthesis failure., Level of Evidence: Level IV, case series.

Purpose: To report mid-term results of total hip arthroplasty (THA) using the Opti-Fix Plus Hip System (Opti-Fix Hip), and to assess the correlations between peri-implant bone changes and the distal medullary occupancy rate., Methods: 11 men (13 hips) and 53 women (58 hips) aged 24 to 87 (mean, 61) years underwent THA using the Opti-Fix Hip, with a modular stem and a distal sleeve, and were followed up for a mean of 6.5 (range, 4.8-9.6) years. Clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) hip score. Implant stability, bone changes around the implant, and the occupancy rate of the stem in the medullary space were examined radiologically. Bone changes around the implant were assessed based on the radiological evidence of a pedestal, osteolysis, stress shielding, and radiolucent lines., Results: The mean JOA score increased significantly after surgery and was maintained at the latest follow-up. Around the acetabular and femoral components respectively, 38 and 58 hips had radiolucent lines, whereas one and 54 hips developed osteolysis. A pedestal appeared in 21 hips and grade-III or higher stress shielding in 30 hips. Two hips showed loosening of the acetabular components, but none in the femoral components. Osteolysis around the stem was frequently observed in hips with poor distal medullary occupancy., Conclusion: Clinical and radiological outcomes of the Opti-Fix Hip were favourable. The low incidence of osteolysis in the distal stem suggests that the proximal circumferential porous coating was effective. Minor osteolysis around the proximal stem was frequently observed, indicating early excessive wear of the polyethylene liner. Its high distal medullary occupancy rate could inhibit stem micromotion and aseptic loosening.