The rate of elderly people over 65 year-old increased from 18.5 % in 2004 to 26.0% in 2015 in Japan. Northern part of Japan is a head of the super-aging society, and the rate already reached 30.9% in 2015. Along with aging society, rapid increase of total hip arthroplasties (THA) has been predicted. The aim of this study is to estimate the trend of total hip arthroplasties in our super-aging area in Northern Japan. Trend on number and rate of THA in one of the local area of leading super-aging society were surveyed in the last decade using the database of diagnostic procedure and surgical records from 2004 to 2015. The cause of revision THA was analyzed in 2004–2009 versus in 2010–2015. Spearman's rank-correlation coefficient and student's t-tests were performed using the PASW 18 software (SPSS Institute Inc). Values of p < 0.05 were considered statistically significant.Background
Methods
Large head metal on metal total hip arthroplasty MOM THA have been consistently shown substantial improvement in wear performance compared with metal on polyethylene articulations. Large diameter femoral heads theoretically can reduce dislocation risk by increasing range of motion before impingement, increasing prosthetic jump distance. However, early failure associated with adverse local tissue reactions (ALTRs) to metal debris is an emerging problem after MOM THA. The purpose of this study was to evaluate mid-term results of MOM THA. Twenty-five patients, 28 hips were included in this study. The average age of the patients at the time of surgery was 66.9 years. Three patients were men and 22 were women. MOM THAs were performed using 28 PINNACLE Cup system (DepPuy) (C-STEM: 23, S-ROM: 5) with posterior approach and head size of 36mm. Twenty-five primary THAs due to osteoarthritis in 22 cases and rheumatoid arthritis (RA) in one, and two revisions due to recurrent dislocation THA patients, were performed. The average follow up was 56.7 months. Evaluation items are JOA score, cup anteversion /lateral opening angle, and complications. Indication of the system were applied for patients with high risk of dislocation such as recurrent dislocation in primary and/or THAs, posterior pelvic tilt, elderly, RA and mental disorders.Background
Materials and Methods
A navigation system is useful tool to evaluate the intraoperative knee kinematics. Rheumatoid arthritis (RA) patients often need to have TKA operation, however, there are few TKA kinematics studies comparing RA and Osteoarthritis (OA) patients. The purpose of this study was to evaluate intraoperative TKA kinematics, and to describe the difference of kinematics between RA and OA patients.Background
Objective
Patients undergoing total hip arthroplasty (THA) stand in the danger, a particularly high risk for venous thromboembolism (VTE). Fondaparinux and edoxaban, which inhibit FXa, indirectly and directly, respectively, have been used for prevention of VTE after THA in Japan. The aim of this study was to compare the efficacy of fondaparinux and edoxaban for VTE after elective THA in Japanese patients. We randomly assigned 320 patients underdoing elective cemented THA to receive postoperative 2.5 mg fondaparinux once daily for first postoperative 3 days and 1.5 mg once daily for the subsequent 7 days (FPX group) [1], postoperative 15 mg edoxaban once daily for postoperative 10 days (EDO15mg group), 30 mg edoxaban once daily for postoperative 10 days (EDO30mg group), and 30 mg edoxaban once daily for first postoperative 3 days and 15 mg once daily for the subsequent 7 days (EDOmix group). Deep venous thrombosis (DVT) was diagnosed by ultrasonography at postoperative day 3 and 14. Computed tomography to detect pulmonary thromboembolism was performed to all patients who had proximal DVTs. The χ2 test with Bonferroni correction was used to compare variables of the incidence of DVT between each group. The intention-to-treat analysis was performed for statistical analysis in each group. The EDO30 mg group and EDOmix group were regarded as one group in the assessment at the postoperative day 3, and named as the EDO30mg+mix group.Introduction
Materials and methods
Acetabular reconstruction of extensive bone defect is troublesome in revision total hip arthroplasty (rTHA). Kerboull or Kerboull type reinforcement acetabular device with allobone grafting has been applied since 1996. Clinical results of the procedure were evaluated. One hundred and ninety-two consecutive revision total hip arthroplasties were performed with allograft bone supported by the Kerboull or Kerboull type reinforcement acetabular device from 1996 to 2009. There were 23 men and 169 women. Kerboull plates were applied to 18 patients, and Kerboull type plates to 174. The mean follow up of the whole series was 8 years (4–18years). The superior bone defect was reconstructed principally by a large bulky allo block with plate system. Medial bone defect was reconstructed by adequate bone chips and/or sliced bone plates. After temporally fixation of bulky bone block with two 2.0mm K-wires, it was remodeled by reaming to fit the gap between host bone and plate, followed by fixation to the iliac bone by screws. Finally, residual space of the defect between host bone and the fixed plated was filled up with morselized cancellous bones, bone chips, and/or wedged bony fragments with impaction. This method was sufficiently applicable to AAOS Typeâ�, II, and III bone defects. In case of AAOS Typeâ�£, the procedure was also available after repairing discontinuation between distal and proximal bones by reconstrusion plate or allografting with tibial bone plates or sliced femoral head.Patients
Surgical Technique
Macrophages phagocytes implant wear debris and produce various cytokines to evoke inflammation and periprosthetic osteolysis of aseptic loosening. It had been reported that expression of Toll-like receptor (TLR) 2 and other TLRs increased in periprosthetic tissues of aseptic loosening. Pathogen-associated molecular patterns (PAMPs) and damaged-associated molecular patterns (DAMPs) have been known as ligands of TLRs and considered to be involved in the osteolytic reactions TLR1, TLR2, TLR6, NLRP3, TNF-α and IL-1β of macrophages in aseptic loose periprosthetic tissues were immnohistorically evaluated and compared to osteoarthritic synovium. RAW264.7 cells, macrophagic cell line, were stimulated by titanium particles (Ti) and lipoteichoic acid (LTA)-coated Ti. The celluar reaction associated with TLR2 and NLRP3 and the correlation of them were analyzed at mRNA expression levels with small-interfering RNA of Introduction
Materials and methods
Biologic agents (BIO) drastically changed the rheumatoid arthritis (RA) therapy from starting to use biologics at 2003 in Japan. The rate of orthopaedic surgery, especially total joint arthroplasty (TJA) may reflect trends in disease severity, management and health outcomes. We surveyed the number and rate of orthopaedic surgeries and TJA in RA treatment with BIO in the last decade, so called BIO-era.Objectives
Methods
Although the treatment for infected total hip arthroplasty (THA) has been still controversial, some reports suggested two-stage revision THA seems to be more preferable rather than one-stage revision. The purpose of this study is to estimate the outcome of treatment for infected THA in our institutions. The medical records of patients who have been underwent surgical treatment for infected THA between 2006 and 2012 in two hospitals and followed more than one year after surgery were reviewed. 34 patients and 35 hips were included. Age at surgery, gender, a period until surgical treatment after diagnosis of infection, method of treatment (debridement, one-stage or two-stage revision THA) and the outcome are estimated for each hips. Remission was defined by the absence of local and systemic sign of implant related infection and the normalization of WBC and C-reactive protein value without antibiotics.Background and Purpose
Patients and methods
Accurate soft tissue balancing has been recognized as important as alignment of bony cut in total knee arthroplasty (TKA). In addition, using a tensor for TKA that is designed to facilitate soft tissue balance measurements throughout the range of motion with a reduced patello-femoral (PF) joint and femoral component in place, PF joint condition (everted or reduced) has been proved to have a significant effect for intra-operative soft tissue balance. On the other hand, effect of patellar height on intra-operative soft tissue balance has not been well addressed. Therefore, in the present study, we investigated the effect of patellar height by comparing intra-operative soft tissue balance of patella higher subjects (Insall-Salvati index>1) and patella lower subjects (Insall-Salvati indexâ‰/1). The subjects were 30 consecutive patients (2 men, 28 women), who underwent primary PS TKA (NexGen LPS-flex PS: Zimmer, Warsaw, IN, USA) between May 2003 and December 2006. All cases were osteoarthritis with varus deformity. Preoperative Insall-Salvati index (ISI) was measured and patients were divided into two groups; the patella higher group (ISIï1/4ž1: 18 knees average ISI was 1.12) and the patella lower group (ISIâ‰/1; 12 knees average ISI was 0.94). Component gap and ligament balance (varus angle) were measured using offset-type tensor with 40lb distraction force after osteotomy with the PF joint reduced and femoral trial in place at 0, 10, 45, 90, 135 degrees of knee flexion. Data of two groups were compared using unpaired t test.Introduction
Materials and methods
Total knee arthroplasty (TKA) with a computer-assisted navigation system has been developed to improve the accuracy of the alignment of osteotomies and implantations. One of the most important goals of TKA is to improve the flexion angle. Although accurate soft tissue balancing has been recognized as an essential surgical intervention influencing flexion angle, the direct relationship between post-operative flexion angle and intra-operative soft tissue balance during TKA, has little been clarified. In the present study, therefore, we focused on the relationship between them in cruciate-retaining (CR) TKA with a navigation system. The subjects were 30 consecutive patients (2 men, 28 women), who underwent primary CR TKA (B. Braun Aesculap, e-motion) between May 2006 and December 2009. TKAs were performed using a image-free navigation system (OrthoPilot; B. Braun Aesculap, Tuttlingen, Germany). All cases were osteoarthritis with varus deformity. Average patient age at the time of surgery was 74.0 years (range, 62-86 years). After all bony resections and soft tissue releases were completed appropriately using a navigation system with tibia-first gap technique, a tensor was fixed to the proximal tibia and the femoral trial was fitted. Using the tensor that is designed to facilitate soft tissue balance measurements throughout the range of motion with a reduced patello-femoral (PF) joint and femoral component in place, the joint component gap and ligament balance (varus angle) were measured after the PF joint reduced and femoral component in place (Fig.1). Assessments of joint component gap and ligament balance were carried out at 0°, 30°, 60°, 90°, 120° flexion angle, which were monitored by the navigation system. Joint component gap change values during 30°- 0°, 60°- 0°, 90°- 0°, 120°- 0° flexion angle were calculated. The correlation between post operative flexion angles and pre-operative flexion angle, intra-operative joint component gaps, joint component gap change values and ligament balances were assessed using linear regression analysis.Introduction
Materials and methods
