Analysis of proteins released from osteoarthritic cartilage by compressive loading.

In osteoarthritis (OA), synovial pathology may be induced by proteins released from degenerated cartilage. This study was conducted to identify the proteins released from OA cartilage. OA cartilage was obtained from OA knees at macroscopically preserved areas (PRES) and degenerated areas (DEG), while control cartilage (CONT) was collected from non-arthritic knees.

Lumbar Fusion including Sacroiliac Joint Fixation Increases the Stress and Angular Motion at the Hip Joint: A Finite Element Study.

Introduction: Adult spinal fusion surgery improves lumbar alignment and patient satisfaction. Adult spinal deformity surgery improves saggital balance not only lumbar lesion, but also at hip joint coverage. It was expected that hip joint coverage rate was improved and joint stress decreased.

Evaluation of bone strength using finite-element analysis in patients with ossification of the posterior longitudinal ligament.

Background Context: Patients with ossification of the posterior longitudinal ligament (OPLL) are often reported to have increased bone mineral density (BMD). The bone strength of the proximal femur measured by quantitative computed tomography-based finite element analysis (QCT/FEA) is reportedly comparable between healthy subjects with and without OPLL. However, the bone strength in symptomatic OPLL patients remains unknown.

Fracture of ossified Achilles tendons: A review of cases.

Fracture of an ossification of the Achilles tendon (OAT) is a rare entity, and its etiology, pathology, and treatment remain unclear. We reviewed and scrutinized 18 cases (16 articles) of the fracture of an OAT. The most common etiologies of the ossifications include previous surgery and trauma.

The attenuation of insulin-like growth factor signaling may be responsible for relative reduction in matrix synthesis in degenerated areas of osteoarthritic cartilage.

Background: In osteoarthritis (OA), cartilage matrix is lost gradually despite enhanced matrix synthesis by chondrocytes. This paradox may be explained, at least partly, by reduced chondrocyte anabolism in degenerated area of OA cartilage. However, to date, it is not known why chondrocyte anabolism is suppressed in those areas.

Evaluations of daily teriparatide using finite-element analysis over 12 months in rheumatoid arthritis patients.

Introduction: The objective of this study was to quantitatively evaluate the effects of daily teriparatide on rheumatoid arthritis patients using predicted bone strength (PBS) assessed by quantitative computed tomography-based finite-element analysis (QCT/FEA) and using bone mineral density (BMD) assessed by dual-energy X-ray absorptiometry (DXA), and to prospectively investigate clinical determinants associated with PBS and BMD increases.

Materials And Methods: Participants comprised 39 patients (mean age, 69 years; disease activity score assessing 28 joints with CRP, 3.0; previous vertebral fractures, 82%) enrolled in this study.

Prediction of the pathological fracture risk during stance and fall-loading configurations for metastases in the proximal femur, using a computed tomography-based finite element method.

Background: It is important to assess the fracture risk associated with metastasis in the proximal femur. The study aimed to clarify the effect of tumor location on the risk of pathological fracture of the proximal femur and investigate the fracture risk not only in the stance-loading configuration (SC), but also in the fall-loading configuration (FC) using a computed tomography (CT)-based finite element (FE) method based on a simulated metastatic model.

Methods: The axial CT scans of the proximal femora of non-osteoporotic healthy men (n = 4; age range, 42-48 years) and osteoporotic post-menopausal women (n = 4; age range, 69-78 years) were obtained with a calibration phantom, from which the three-dimensional FE models were constructed.

Assessing joint destruction in the knees of patients with rheumatoid arthritis by using a semi-automated software for magnetic resonance imaging: therapeutic effect of methotrexate plus etanercept compared with methotrexate monotherapy.

Objectives: To evaluate the prevention of knee joint destruction and clinical efficacy of methotrexate (MTX) plus etanercept (ETN) compared with MTX monotherapy in patients with rheumatoid arthritis (RA) by using semi-automated software for magnetic resonance imaging (MRI) scan analysis.

Materials And Methods: This study enrolled patients with active moderate-to-severe RA who displayed an inadequate response to oral MTX at screening. Patients were assigned to receive either MTX plus ETN or MTX monotherapy (≥10 mg/week).

[New methods for the evaluation of bone quality. Bone quality evaluation by QCT.].

In osteoporosis, the risk of fracture is influenced by decrease of bone mineral density and deterioration of bone quality. The latter includes deterioration of the material and structural properties of bone. These changes arise from the influence of changes in hormonal balance, aging, changes in mechanical stress, lifestyle-related diseases, etc.

Successful treatment of a fracture of a huge Achilles tendon ossification with autologous hamstring tendon graft and gastrocnemius fascia flap: a case report.

Background: Fracture of an ossified Achilles tendon is a rare entity, and no standard treatment has been established. This is the first report to describe the use of a hamstring tendon graft and gastrocnemius fascia flap for Achilles tendon reconstruction.

Case Presentation: We present the case of a 50-year-old woman with fracture of an ossified Achilles tendon.

The impact of joint disease on the Modified Health Assessment Questionnaire scores in rheumatoid arthritis patients: A cross-sectional study using the National Database of Rheumatic Diseases by iR-net in Japan.

Objectives: To investigate the effect of bilateral and unilateral joint disease on the Modified Health Assessment Questionnaire (MHAQ) scores and the differences in joint weighting in rheumatoid arthritis patients.

Methods: A total of 9212 subjects from the Japanese nationwide cohort database NinJa, 2011, were analyzed. The presence or absence of disease in each joint, including swelling and/or tenderness, was investigated.

The effect of cartilage degeneration on ultrasound speed in human articular cartilage.

Objectives: We investigated the effect of cartilage degeneration on ultrasound speed in human articular cartilage in vitro.

Methods: Ultrasound speed was calculated by the time-of-flight method for 22 femoral condyle osteochondral blocks obtained from osteoarthritis patients. In parallel, histological evaluation of specimens was performed using the modified Mankin and OARSI scores.

Prevalence of total knee arthroplasty and its predictive factors in Japanese patients with rheumatoid arthritis: Analysis using the NinJa cohort.

Objectives: The aim of this study was to clarify the prevalence and the predictive factors for undergoing total knee arthroplasty (TKA) among patients with rheumatoid arthritis (RA).

Methods: The data of 1,134 patients with RA who were enrolled in the Japanese nationwide cohort database NinJa in 2003 and consecutively followed up until 2009 were analyzed.

Results: Seventy-six patients underwent TKA during the observation period.

Prediction of proximal femur strength by a quantitative computed tomography-based finite element method--Creation of predicted strength data of the proximal femur according to age range in a normal population.

Objective: The objective of this study was to investigate the factors that affect the predicted bone strength of proximal femur in Japanese population.

Methods: Participants (552 men and 273 women) in a health checkup program with computed tomography (CT) at the University of Tokyo Hospital were enrolled in this study. Three-dimensional finite element models of the proximal femur were constructed from CT data of the participants with simultaneous scans of a calibration phantom containing hydroxyapatite rods.

Development of femoral bone fracture model simulating muscular contraction force by pneumatic rubber actuator.

In femoral fracture reduction, orthopedic surgeons must pull distal bone fragments with great traction force and return them to their correct positions, by referring to 2D-fluoroscopic images. Since this method is physically burdensome, the introduction of robotic assistance is desirable. While such robots have been developed, adequate control methods have not yet been established because of the lack of experimental data.

[Anti-osteoporosis drugs based on the guidelines for the Prevention and Treatment of Osteoporosis (2011 edition) ].

The aim of osteoporosis treatment is to reduce fracture risk. Many kinds of anti-osteoporosis drugs are available in these days, and most of them increase bone mineral density and reduce the risk of fractures. Japanese 2011 guidelines for prevention and treatment of osteoporosis documents the recommendation level of each osteoporosis drugs.

[Secondary osteoporosis or secondary contributors to bone loss in fracture. Therapeutic intervention of rheumatoid arthritis bone loss].

In rheumatoid arthritis (RA) , the osteoclast pathway is activated by abnormal immune conditions accompanied by chronic inflammation resulting in periarticular osteoporosis and local bone destruction around joints. In addition, multiple factors lead to systemic osteoporosis, including reduced physical activity and pharmacotherapies such as steroids. These conditions cause decreased bone mineral density and bone quality, and expose patients to an increased risk of fracture.

[Bone structure in rheumatoid arthritis].

In rheumatoid arthritis (RA) , the osteoclast pathway is activated by abnormal immune conditions accompanied by chronic inflammation, resulting in periarticular osteoporosis and local bone destruction around joints. In addition, multiple factors, including reduced physical activity and pharmacotherapies such as steroids, lead to systemic osteoporosis. These conditions cause decreasing bone mineral density and deterioration of bone quality, and expose patients to increased risk of fracture.

[Rheumatoid arthritis and bone -periarticular and systemic bone loss-].

In rheumatoid arthritis (RA) , the osteoclast pathway is activated by an abnormal immune condition accompanied by chronic inflammation, resulting in periarticular osteoporosis and local bone destruction around joints. In addition, multiple factors including pharmacotherapies such as steroids, and reduced physical activity, lead to systemic osteoporosis. These conditions expose patients to increased fracture risk.

Surgical tool alignment guidance by drawing two cross-sectional laser-beam planes.

Conventional surgical navigation requires for surgeons to move their sight and conscious off the surgical field when checking surgical tool's positions shown on the display panel. Since that takes high risks of surgical exposure possibilities to the patient's body, we propose a novel method for guiding surgical tool position and orientation directly in the surgical field by a laser beam. In our navigation procedure, two cross-sectional planar laser beams are emitted from the two laser devices attached onto both sides of an optical localizer, and show surgical tool's entry position on the patient's body surface and its orientation on the side face of the surgical tool.

[Etiology of osteoporosis -decrease of bone mineral density and deterioration of bone quality-].

In osteoporosis, the risk of fracture is influenced by decrease of bone mineral density and deterioration of bone quality. The latter includes deterioration of the material and structural properties of bone. These changes arise from the influence of changes in hormonal balance, aging, changes in mechanical stress, lifestyle-related diseases, etc.

A fluorolaser navigation system to guide linear surgical tool insertion.

Purpose: Conventional navigation systems for minimally invasive orthopedic surgery require a secondary monitor to display guidance information generated with CT or MRI images. Newer systems use augmented reality to project surgical plans into binocular glasses. These surgical procedures are often mentally challenging and cumbersome to perform.

Effect of low-intensity pulsed ultrasound stimulation on gap healing in a rabbit osteotomy model evaluated by quantitative micro-computed tomography-based cross-sectional moment of inertia.

Background: It has been previously demonstrated that low-intensity pulsed ultrasound stimulation (LIPUS) enhances formation of the medullary canal and cortex in a gap-healing model of the tibia in rabbits, shortens the time required for remodeling, and enhances mineralization of the callus. In the current study, the mechanical integrity of these models was confirmed. In order to do this, the cross-sectional moment of inertia (CSMI) obtained from quantitative micro-computed tomography scans was calculated, and a comparison was made with a four-point bending test.

Measurement of articular cartilage thickness using a three-dimensional image reconstructed from B-mode ultrasonography mechanical scans feasibility study by comparison with MRI-derived data.

The present study aimed to develop a method to measure three-dimensional (3-D) thickness of cartilage (Tc) at the femoral condyle using B-mode ultrasonography (US) and to clarify the feasibility of US in clinical evaluations of articular cartilage by comparing the results with 3-D measurement values using magnetic resonance imaging (MRI) and assessing repeatability. The medial surface of the right knees of two healthy male volunteers (age, 37 and 59 years) and the knees on affected side of three male patients with osteoarthritis (OA) (age, 73, 81 and 83 years) were scanned using B-mode US with the knee flexed at 120°. The range of the angle of probe rotation for the arm was 0-80° and B-mode images (total, 101 images) were acquired every 0.