In a cruciate retaining total knee arthroplasty (CR-TKA) for patients with flexion contracture, to ensure that an extension gap is of sufficient size to install an implant, the amount of distal femur bone resection needed is frequently larger in a patient with knee flexion contracture than in one without contracture. In this study, we compared the distal femur bone resection amount, the component-secured extension gap margin value, and the range of motion at 6 months after surgery between patients with knee flexion contracture and those without knee flexion contracture. We examined 51 joints including 27 joints in patients with preoperative extension limitation of less than 5 degrees (the F0 group) and 24 joints in patients with limitation of 15 degrees or larger (up to 33 degrees; the FC group) who underwent CR-TKA with LCS RP (DePuy Synthes) between May 2013 and April 2014. In case with an extension gap 3 mm or smaller than the flexion gap after initial bone resection, we released posterior capsule adequately, trying to minimize the distal femur additional bone resection amount as possible. With installation of a femoral trial, the component gaps were measured using spacer blocks. The measured parameters included the intraoperative bone resection length, gap difference (FG − EG, i.e., difference between the flexion gap [FG] and extension gap [EG]), and range of motion 6 months after surgery.Objective
Method
While the short-stem design is not a new concept, interest has risen with increasing utilization of less invasive techniques. Especially, short stems are easier to insert through the direct anterior approach. In the radiographic evaluation of patients who underwent primary uncemented total hip arthroplasty (THA) using a TaperLoc Microplasty femoral component (Biomet, Warsaw, IN, USA), cortical hypertrophy was occasionally detected on three-month postoperative radiographs. The purpose of this study was to evaluate the radiographic changes associated with cortical hypertrophy of the femur three months postoperatively. Between May 2010 and September 2014, 645 hips in 519 patients who received the TaperLoc Microplasty stem were evaluated. Six hips in four patients were lost to follow-up. Finally, 639 hips in 515 patients were included in this study; 248 hips underwent bilateral simultaneous THA and 391 hips underwent unilateral THA. There were 103 males and 412 females (average age, 63 ± 10.1 years; average height, 156 ± 8.13 cm; and average weight, 58 ± 12.2 kg). The postoperative radiographs immediately taken after the operation and three months postoperatively were compared. We evaluated cortical hypertrophy around the stem. Cortical hypertrophy >2 mm on anterior-posterior X-ray was defined as “excessive periosteal reaction” (Figure 1).Objective
Methods
In Total Knee Arthroplasty (TKA), it is important to adjust the difference of the flexion-extension gap (gap difference) to get the good range of motion and the sufficient stability. However the effect of the gap adjustment on the post-operative knee flexion angle(KFA) is unknown. We investigated the relationship between the gap difference and the postoperative KFA improvement rate. 179 knees that underwent LCS RP TKA were investigated more than 6 months after surgery(Feb/2013∼Sep/2014). The patients were 49 men and 130 women, of average age 70.6 years (50∼88) and BMI 26.3 (17.0∼55.2). Among them, 175 knees were knee osteoarthritis and 2 joints were rheumatoid arthritis, 2 joints were avascular necrosis. The extension gap was typically prepared with a measured resection, and a small temporary flexion bone gap was prepared with a 4mm resection of the femoral posterior condyle using the pre-cut method(fig 1). Then we measured the gaps under the installation of the Pre-cut Trial(PT; Kaneyama 2011)by the off-set spacer with 1mm increments in patella reduction position(fig 2,3). The final amount of bone resection was determined by comparison of the measured gaps and gaps required for implantation. We calculated the differences between the final extension gap and the final flexion gap and their relationship with knee flexion angles at 6 months postoperatively were analyzed.Objective
Methods
Incorrect restoration of the joint line during total knee arthroplasty (TKA) can result in joint instability, anterior knee pain, limited range of motion, and joint stiffness. Although restoration of the correct joint line (i.e., creating an optimal gap in extension and flexion) should be considered in all TKA procedures, no surgical techniques have been established for restoring it. We performed the femoral posterior condylar precut technique A total of 91 knees in 73 patients who underwent primary TKA between June and December 2013 were reviewed retrospectively. The posterior cruciate ligament was preserved in all patients. First, in the femoral posterior condylar precut technique, the extension gap was created by the measured resection technique. Then we created a temporary gap in flexion 4 mm smaller than that created by the measured resection technique and remove posterior osteophytes and soft tissue for good ligament balance. Once the component gap was determined, final femoral posterior condyle cutting was performed to create an optimal gap and rotation. We evaluated the joint line from the differences in thickness between the surgically removed femoral bone and femoral components, and revised the thickness of the bone saw accordingly. The value was positive when the joint line had been raised and negative when it had been lowered.Introduction
Methods
Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) is subjective assessment of coxarthropathy and reflects the satisfaction level of the patient. Recently, the use of JHEQ as a postoperative assessment of total hip arthroplasty (THA) has become widespread. The aim of this study was to investigate the clinical outcomes of bilateral simultaneous THA through the direct anterior approach (DAA) using JHEQ. This study included 34 patients (41 hips) who were treated with first THA at our hospital from January to March 2013 and were available for evaluation of clinical outcomes 1 year after surgery. Of these, 7 (2 males and 5 females; mean age, 54.7 years) underwent bilateral simultaneous THA (group B), and 27 (2 males and 25 females; mean age, 64.2 years) underwent unilateral THA (group U). Thirty patients were preoperatively diagnosed with hip osteoarthritis, and 4 were diagnosed with avascular necrosis of the femoral head. All patients were treated through DAA in a supine position under general anaesthesia. Items for evaluation included clinical outcomes, Japanese Orthopaedic Association Hip score (JOA score) and JHEQ.Purpose
Methods
Bulk bone grafting of the cup is commonly used in total hip arthroplasty (THA) for developmental dysplasia. However, it carries a risk of the graft collapse in the mid-term or long-term results. The purpose of this study is to describe our new bulk bone grafting technique and review the radiographic and clinical results. We retrospectively reviewed 85 hips in 74 patients who had undergone bulk bone grafting in total hip arthroplasty for developmental dysplasia between 2008 and 2013. We excluded patients who had any previous surgeries or performed THA with the femoral shortening osteotomy. According to the Crowe classification, 4 hips were classified as Type 1, 28 as Type 2, 35 as Type 3, and 18 as Type 4. Follow-up was at a mean of 4.0 years (1 to 6.1). The surgery was performed using the direct anterior approach on a standard surgical table. The acetabulum was reamed for as close to the original acetabulum as possible. The pressfit cementless cup was impacted into the original acetabulum. After the pressfit fixation of the cup was achieved, two or three screws were used to reinforce the fixation. The superior defect of the acetabulum was packed with sufficient amount of morselized bone graft. Then, the bulk bone was placed on the morselized bone graft and fixed with one screw. Post-operatively, there were no restrictions to movement or position. On the first day after surgery, the patient was allowed to walk with full weight-bearing. We measured the height of the hip center from the interteardrop line and the pelvic height on anteroposterior roentgenograms of the pelvis and calculated the ratio of the hip center to the pelvic height. We defined the anatomical hip center as the height of the center less than 15% of the pelvic height.Introduction
Patients and Methods
In Total Knee Arthroplasty (TKA), closed drains have been conventionally used to prevent hematoma. Recently reported “no-drain” methods have been demonstrated to be safe and effective, especially for decreasing hemorrhage. However, there has been no report of a major study on a no-drain method in simultaneous bilateral TKA, only a few small studies. Therefore, this study evaluated the efficacy of no-drain placement in simultaneous bilateral TKA. Our study included 75 patients (150joints) with preoperative hemoglobin(Hb) level of at least 11.0 g/dl who underwent simultaneous bilateral TKA performed by the same surgeon in our department between January 2012 and December 2013. There were 12men and 63women, of average age 70.7 ± 7.9years (mean ± SD) and BMI 25.6± 3.8 (mean ± SD). Among them 72 patients had knee osteoarthritis and 3 patients had rheumatoid arthritis. The patella was not replaced in any of the cases. TKAs were performed separately on each knee. A tourniquet was applied between the initial skin incision and the postoperative dressing, and 1000 mg of tranexamic acid was injected into each joint after wound closure.(Introduction)
(Methods)
Total knee arthroplasty (TKA) should aim to adjust the component gap (CG) difference between extension and flexion. However, this difference cannot be measured without placement of a femoral component. The bone gap reportedly decreases in extension after component setting. In contrast, it may be possible to use the mean value of the CG difference in several patients to adjust femoral resection amount beforehand. The purpose of this study is to evaluate the technique of adjusting CG difference using the mean values with measured resection technique (MRT) in TKA. The subjects were 222 knees (40 male knees, 182 female knees; mean age 70.4 years). To adjust the CG difference after estimation, the femoral posterior condylar pre-cut technique was used. Extension gap was created by usual bone resection; 4 mm of the femoral posterior condyle was pre-cut, and after all osteophytes and soft tissues had been treated, a pre-cut trial component (thickness of 8 mm for distal femur and 4 mm for posterior condyle without the anterior portion) was mounted, achieving the same condition as the setting of a femoral component in MRT (Fig. 1). When the posterior cruciate ligament (PCL) could be easily preserved by intraoperative gap assessments, the PCL was preserved (190 knees, 86%).Introduction:
Materials and methods:
In posterior cruciate ligament (PCL)-preserving total knee arthroplasty (TKA), it is important to determine whether the PCL is properly functioning after surgery. As the PCL is partly damaged during the operation, we cannot rule out the possibility that excessive tension further damages the remaining PCL resulting in dysfunction or that initial functioning of the PCL is lost due to excessively low tension. However, it is normally difficult to examine whether the PCL has remained intact and is still functional after TKA. The objective of this study was to visualize knee joint flexion after TKA by MRI and evaluate the PCL based on these images. PCL-preserving TKA was performed in 41 knees using the Fine Total Knee System® (Nakashima Medical, Okayama, Japan) where a titanium component can be selected for both the femur and the tibia. We visualized knee flexion positions by MRI at 6 months after surgery and evaluated visualization or non-visualization of the PCL, the relationship between knee flexion angle and PCL elevation angle against the plane of the tibial joint vertical to the tibial axis, and the forms of PCL based on the MRI data.Introduction
Method
