Proper acetabular cup placement is very important factor for successful clinical results in total hip arthroplasty (THA). Malposition of acetabular cup has been linked to increased rates of dislocation, impingement, pelvic osteolysis, cup migration, leg length discrepancy and polyethylene wear. Recently, some authors reported usefulness of navigation systems to set the acetabular cups with correct position. The purpose of this study is to evaluate the accuracy of acetabular cup placement in THA using computed tomography (CT)-based navigation system. Subjects were 235 hip joints we performed primary THA using CT based navigation system (Stryker® Navigation System, Stryker Corporation, Kalamazoo, MI, USA) from 2008 to 2014 and could assess the implant position by postoperative CT images. Their average age was 65.1 years (range 35–88). In all cases, non-cemented acetabular cups were implanted. TriAD cups (Stryker®) were used in 31 hips, and Tritanium cups (Stryker®) were used in 15 hips, and Trident cups (Stryker®) were used in 189 hips. Registration in this navigation system used surface matching system. We designed cup implantation using preoperative CT images and 3-dimensional (3-D) templates. The planned position of acetabular cup was in principle 40 degrees of inclination and 20 degrees of anteversion. However, we adjusted the better position of the cups according to pelvic tilt and femoral neck anteversion. When we placed acetabular cups, the position, inclination and anteversion, were measured by navigation system. After surgery, the positions of the cups were measured using postoperative CT images, navigation software and 3-D templates. Postoperative position using CT images were adjusted according to preoperative pelvic plane. The discrepancies between intraoperative navigation data and postoperative CT images data were analyzed as accuracy of navigation system in cup placement.Introduction
Material and Methods
Acetabular reconstruction of a total hip arthroplasty (THA) for a case with severe bone loss is most challenging for surgeon. Relatively high rate of failure after the reconstruction surgery have been reported. We have used Kerboull-type acetabular reinforcement devices with morsellised or bulk bone allografts for these cases. The purpose of this study was to examine the midterm results of revision THA using Kerboull-type acetabular reinforcement devices. We retrospectively reviewed 20 hips of revision THA (20 patients) between February 2002 and August 2010. The mean age of the patients at the time of surgery was 67.4 years (range 45–78). All of the cases were female. The mean duration of follow-up was 6.5 years (range 2.1–10.4). The reasons of revision surgeries were aseptic loosening in 10 hips, migration of bipolar hemiarthroplasty in 8 hips, and rheumatoid arthritis in 2 hips. We classified acetabular bone defects according to the American Academy of Orthopaedic Surgeons (AAOS) classification; we found two cases of Type II and eighteen cases of Type III. In terms of bone graft, we performed both bulk and morsellised bone grafts in 6 hips and morsellised bone grafts only in 14 hips. We assessed cup alignment using postoperative computed tomography (CT) and The post-operative and final follow-up radiographs were compared to assess migration of the implant. We measured the following three parameters: the angle of inclination of the acetabular device (Fig. 1); the horizontal migration (Fig. 2a); and vertical migration (Fig. 2b). Substantial migration was defined as a change in the angle of inclination of more than 3 degrees or migration of more than 3 mm. The pre- and postoperative hip functions were evaluated using the Japanese Orthopaedic Association (JOA) hip score.Introduction
Patients and methods
Ankle arthrodesis is a common treatment for destroyed ankle arthrosis with sacrificing the range of motion. On the other hand, total ankle arthroplasty (TAA) is an operation that should develop as a method keeping or improving range of motion (ROM); however, loosening and sinking of the implant have been reported in especially constrained designs of the implant. The concept of FINE TAA is the mobile bearing system (Nakashima Medical Co., Ltd, Okayama Japan) that can reduce stress concentration to implants. The purpose of this study is to evaluate the short-term results of FINE TAA. We performed FINE TAA for osteoarthritis (OA) (2 ankles of 2 patients) and rheumatoid arthritis (RA) (4 ankles of 3 patients). All patients were female. The mean age of the patients was 71.4 years old at the operation. The mean follow-up period was 32.6 (range, 18–55) months. All patients were assessed for Japan Orthopedic Association (JOA) score and ROM in plantar flexion and dorsiflexion at the point of pre-operation and final follow-up. We evaluated radiolucent line, subsidence, and alignment of implants at the latest follow-up.Introduction
Objectives and Methods
While research has been carried out widely for sagital pelvic tilt, research reports for coronal pelvic obliquity are few. The aim of this study is to evaluate changes of the pelvic obliquity before and after total hip arthroplasty. This retrospective study includes 146 cases of hips that were received total hip arthroplasty. There were 20 cases of revision, and 2 cases of re-revision. 17 cases were received bilateral total hip arthroplasty. The standing plain X-ray was used for evaluation of the pelvic obliquity in both before and 1-year after surgery. The correlation of pelvic obliquity was assessed between before and after surgery. 146 cases were classified into 3 groups (A, B, and C) according to the severity of the pelvic obliquity (0º−3º, 3º−6º, and >6º). Among the groups, statistical analysis was evaluated in the leg length discrepancy and the range of motion of the hip (flexion, extension, abduction, adduction, internal and external rotation) before and after surgery with 95% confidence intervals.Introduction
Material and Methods
Continuous epidural anesthesia or femoral nerve block has decreased postoperative pain after total knee arthroplasty to some extent. Although the established efficacy of these pain relief method, some adverse events such as hematoma or muscle weakness are still problematic. Intraoperative local infiltration of analgesia (LIA) has accepted as a promising pain control method after total knee arthroplasty. The safety and efficacy of LIA has been reported, although there are still limited evidence about the effect of LIA on quadriceps function and recovery of range of motion in early post-operative phase. The purpose of this study is to compare the quadriceps function and range of motion after TKA between the LIA with continuous epidural anesthesia and continuous epidural anesthesia alone. Thirty patients with knee osteoarthritis who underwent primary TKA were included in this study. Patients who took anticoagulants were treated continuous epidural anesthesia alone (n=11) and the other patients were treated with LIA with continuous epidural anesthesia (n=19). A single surgeon at our department performed all surgeries. Surgical procedure and rehabilitation process was identical between two groups. Before the implantation, analgesic drugs consisting of 20 ml of 0.75 % ropivacaine and 6.6 mg of dexamethasone were injected into the peri-articular tissues. In each group, fentanyl continuous epidural patient-controlled analgesia (PCA) was also used during 48-h post-operative period. Knee flexion and extension angle were evaluated before surgery, post-op day 3, 7, 10 and 14. The quadriceps function was evaluated by quadriceps peak torque at 30° and 60° flexion using VIODEX. The peak torque was recorded preoperatively, day 14 and 3 month after surgery. The difference between two groups was analyzed by Mann Whitney U-test using Prism 6, a statistical software.Background
Methods
