While changes in lower limb alignment and pelvic inclination after total hip arthroplasty (THA) using certain surgical approaches have been studied, the effect of preserving the joint capsule is still unclear. We retrospectively investigated changes in lower limb alignment, length and pelvic inclination before and after surgery, and the risk of postoperative dislocation in patients who underwent capsule preserving THA using the anterolateral-supine (ALS) approach. Between July 2016 and March 2018, 112 hips (non-capsule preservation group: 42 hips, and capsule preservation group: 70 hips) from patients with hip osteoarthritis who underwent THA were included in this study. Patients who underwent spinal fusion and total knee arthroplasty on the same side as that of the THA were excluded. Using computed tomography, we measured lower limb elongation, external rotation of the knee, and femoral neck/stem anteversion before operation and three to five days after operation. We examined the pelvic inclination using vertical/transverse ratio of the pelvic cavity measured by X-ray of the anteroposterior pelvic region in the standing position before and six to 12 months after operation. All operations were performed using the ALS approach and taper wedge stem.Purpose
Methods
Aims
Patients and Methods
Patellofemoral compilcations are among the most frequently observed adverse events after total knee arthroplasty. The posterior location with Femoral component of conventional TKA in AP alignment cause paradoxical movement, but, guide motion TKA (Journey.2.BCS) with anterior post-cam remain a correct AP alignment. The purpose of this study was to investigate patellofemoral (PF) contact stress between Bi-Cruciate Substituting TKA (Journey.2.BCS) and CR TKA (Journey.CR). We evaluated 22 knees with medial compartment osteoarthritis who underwent. Simultaneous bilateral TKA. The prospective randomized study was to measure intraoperative PF contact stress by a patellofemoral sensor (Kyowa Co., Ltd., Tokyo, Japan) comparing the identical Bi-Cruciate Substituting or CR Journey.2 total knee prostheses implanted bilaterally in the same patient.INTRODUCTION
METHODS
Normal kinematics have not been achieved in TKA design. Recently, knee simulation studies have suggested that a medial pivot TKA can achieve the anatomic pathway that reduce mid-flextion rollback and increase lateral rotation. However, the influence of postoperative flextion angle associated with medial tightness for guide motion TKA remains poorly understood. The purpose of this study was to investigate the effect of postoperative flextion angle and clinical outcomes associated with tightness for medial component gap (MCP). We evaluated 79 patients who underwent 84 medial pivot The Journey.2. Bi-Cruciate Substituting (BCS) TKA using the measured resection tequnique, from June 2014 to March 2016. We measured the gaps after implantation from extension to full flextion with reduced patella by constant distraction force (120N). A new tensor has the same articular shapes as that the tibial liner, including anterior and posterior structure.INTRODUCTION
METHODS
Polymethylmethacrylate (PMMA) has been used for total knee arthroplasty (TKA) as a method of fixation; however, its durability has been questionable for the long-term use because of the loosening after the cement deterioration, its vulnerability toward infectious resistance, and a smaller amount of healthy bone left for the knee revision surgery. Especially, a decrease of bone density on the proximal tibia has been believed to be triggered as a result of stress shielding. When compared with a cemented TKA, a cementless TKA reduces the amount of bone loss after surgery. In 1999, the Trabecular Metal (TM), with its main composition being the porous tantalum metal, became available as a choice of the porous cementless knee joint prosthesis. The characteristics of porous tantalum metal are its great affinity to the bone as well as its similarity to cancellous bone. The porous tantalum metal starts to bond with osteoblasts, and fills up 80% of porous structure in one year; therefore, it has been characterized by its higher initial fixation strength. However, it is questionable if strong fixation strength due to bone ingrowth between the tibial tray mainly made up with the porous tantalum metal and a cancellous bone will continually be kept. Bobyn, JD, Dunbar et al. have acknowledged the existence of bone ingrowth based on the radiographic evaluation; however, their data had not been quantified in their report. In this study, the bone ingrowth density have periodically quantified using 3D bone morphometric software (TRI/3D-BON64.RATOC) after taking CT of the knee joint prosthesis. From October 2011, we have reviewed 45 medial osteoarthritis knees that underwent MIS-TKA using Trabecular Metal Modular Tibia CR-type (Zimmer, Inc, Warsaw, Indiana). Ages range from 61–89 years (mean, 74.5 years), and 5 males (7 knees), and 32 females (38 knees) participated in this study. After taking CT picture with the Phantom under lower extremities, the bone ingrowth density are quantified utilizing 3D bone morphometric software (TRI/3D-BON63.RATOX). Measured areas are divided into 6 zones that are right under the pegs of TM femoral component, and the bone ingrowth density (BMC/TC) between TM and cancellous bone were periodically measured on 3, 6, 9, 12,15,18,21,24.27 months after the surgery. Also, intra-zone comparison were implemented by each period among Medial (Zone 1), Lateral (Zone 2), Medial Anterior (Zone 3), Medial Posterior (Zone 4), Lateral Anterior (Zone 5), and Lateral Posterior (Zone 6). Mann-Whitney U test and Student's t-test were used for statistical analysis. All cases of tibial component alignment was within 3 degree varus-valgus to neutral alignment.Background
Material and Methods
A 51 years old female who experienced difficulty in gait ambulation due to secondary osteoarthritis of knee showed knee instability caused by paralysis associated with poliomyelitis and scoliosis. At the first medical examination, right knee range of motion was 0° to 90°, and spino malleolar distance (SMD) showed 72cm for the right leg, 78cm for the left leg, and the bilateral comparison of SMD indicated the leg length discrepancy of 6cm. The patient has a history of surgeries with an anterior – posterior instrument for the treatment of scoliosis, and with Langenskiöld method for the paralyzed right knee at the age of seventeen. The patient also experienced varus degeneration at the age of twenty seven, which was surgically treated with high tibial osteotomy. In this case, a reoperation of her right knee was performed due to the reoccurrence of the knee pain. Preoperative planning was performed using Patient-matched instrument (Signature; Biomet) which was created based on computed tomography data. Each part of osteotomy followed the resection guide by Signature, and a total knee arthroplasty was carried out using the Rotating Hinge Knee System (Zimmer, warsaw. Inc). Two week after the operation, the patient showed the ability to walk without any assistance, and has been in a good condition.
We used interconnected porous calcium hydroxyapatite ceramic to bridge a rabbit ulnar defect. Two weeks after inducing the defect we percutaneously injected rabbit bone marrow-derived mesenchymal stromal cells labelled with ferumoxide. The contribution of an external magnetic targeting system to attract these cells into the ceramic and their effect on subsequent bone formation were evaluated. This technique significantly facilitated the infiltration of ferumoxide-labelled cells into ceramic and significantly contributed to the enhancement of bone formation even in the chronic phase. As such, it is potentially of clinical use to treat fractures, bone defects, delayed union and nonunion.
