There are concerns regarding complications and longevity of total elbow arthroplasty (TEA) in young patients, and the few previous publications are mainly limited to reports on linked elbow devices. We investigated the clinical outcome of unlinked TEA for patients aged less than 50 years with rheumatoid arthritis (RA). We retrospectively reviewed the records of 26 elbows of 21 patients with RA who were aged less than 50 years who underwent primary TEA with an unlinked elbow prosthesis. The mean patient age was 46 years (35 to 49), and the mean follow-up period was 13.6 years (6 to 27). Outcome measures included pain, range of motion, Mayo Elbow Performance Score (MEPS), radiological evaluation for radiolucent line and loosening, complications, and revision surgery with or without implant removal.Aims
Methods
The aim of this study was to report the mid-term clinical outcome
of cemented unlinked J-alumina ceramic elbow (JACE) arthroplasties
when used in patients with rheumatoid arthritis (RA). We retrospectively reviewed 87 elbows, in 75 patients with RA,
which was replaced using a cemented JACE total elbow arthroplasty
(TEA) between August 2003 and December 2012, with a follow-up of
96%. There were 72 women and three men, with a mean age of 62 years
(35 to 79). The mean follow-up was nine years (2 to 14). The clinical condition
of each elbow before and after surgery was assessed using the Mayo
Elbow Performance Index (MEPI, 0 to 100 points). Radiographic loosening
was defined as a progressive radiolucent line of >1 mm that was
completely circumferential around the prosthesis.Aims
Patients and Methods
This study aimed to examine the effects of SRT1720, a potent SIRT1 activator, on osteoarthritis (OA) progression using an experimental OA model. Osteoarthritis was surgically induced by destabilization of the medial meniscus in eight-week-old C57BL/6 male mice. SRT1720 was administered intraperitoneally twice a week after surgery. Osteoarthritis progression was evaluated histologically using the Osteoarthritis Research Society International (OARSI) score at four, eight, 12 and 16 weeks. The expression of SIRT1, matrix metalloproteinase 13 (MMP-13), a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5), cleaved caspase-3, PARP p85, and acetylated nuclear factor (NF)-κB p65 in cartilage was examined by immunohistochemistry. Synovitis was also evaluated histologically. Primary mouse epiphyseal chondrocytes were treated with SRT1720 in the presence or absence of interleukin 1 beta (IL-1β), and gene expression changes were examined by real-time polymerase chain reaction (PCR).Objectives
Methods
Diabetes mellitus (DM) is known to impair fracture healing. Increasing evidence suggests that some microRNA (miRNA) is involved in the pathophysiology of diabetes and its complications. We hypothesized that the functions of miRNA and changes to their patterns of expression may be implicated in the pathogenesis of impaired fracture healing in DM. Closed transverse fractures were created in the femurs of 116 rats, with half assigned to the DM group and half assigned to the control group. Rats with DM were induced by a single intraperitoneal injection of streptozotocin. At post-fracture days five, seven, 11, 14, 21, and 28, miRNA was extracted from the newly generated tissue at the fracture site. Microarray analysis was performed with miRNA samples from each group on post-fracture days five and 11. For further analysis, real-time polymerase chain reaction (PCR) analysis was performed at each timepoint.Objectives
Methods
Low-intensity pulsed ultrasound (LIPUS) enhanced osteogenic differentiation of osteoprogenitor cells derived from mouse induced pluripotent cells (iPSCs) without embryoid body formation. Our findings provide insights on the development of LIPUS as an effective technology for bone regeneration strategies using iPSCs. iPSCs represent a promising cell source for regenerative medicine such as bone regeneration because of their unlimited self-renewal property and ability of differentiation into all somatic cell types. Recently, we developed an efficient protocol for generating a highly homogeneous population of osteoprogenitor cells from embryonic stem cells by using a direct-plating method without EB formation step. It is well-recognised that LIPUS accelerates the fracture healing. There have been several reports showing that LIPUS stimulates the osteogenic differentiation of mesenchymal stem cells (MSCs) Summary Statement
Introduction
iPSCs represent a promising cell source for bone regeneration. To generate osteoprogenitor cells, most protocols use the generation of embryoid bodies (EBs). However, these protocols give rise to heterogeneous population of different cell lineage. We hypothesized that a direct plating method without EB formation step could be an efficient protocol for generating a homogeneous population of osteoprogenitor cells from iPSCs.Introduction
Hypothesis
Biomechanical stimuli have fundamental roles in the maintenance and remodeling of ligaments including collagen gene expressions. Mechanical stretching signals are mainly transduced by cell adhesion molecules such as integrins. However, the relationships between stress-induced collagen expressions and integrin-mediated cellular behaviors are still unclear in anterior cruciate ligament cells. Human ACL cells were harvested from ligament samples donated by patients who underwent total knee arthroplasties with informed consents. Interface cells were isolated from the 5-mm-end of ACL. Midsubstance cells were cultured from the middle part of ACL. The cells were seeded onto stretch chambers (2Ä−2 cm, 50,000 cells/chamber) and uni-axial cyclic mechanical stretch (0.5 Hz, 7%) was applied for 2 h using a ST140. RNA samples were reverse-transcripted and quantitative real-time RT-PCR analysis were performed. To inhibit the function of integrin alphaVbeta3 subunit or alpha5 in stretching experiments, anti-human integrin alphaVbeta3 and alpha5 functional blocking antibodies (alphaVbeta3: 20 mg/ml, alpha5: 4 mg/ml) were used. To investigate the cellular attachments responding to mechanical stretch, we observed the distribution of integrins and stress fibers in both ACL cells. The shape of midsubstance cells showed spindle and fibroblastic cellular morphologies. On the other hand, the interface cells displayed chondroblastic appearances such as small and triangular morphologies. The expressions of COL1A1, COL2A1, and COL3A1 genes were detected in the tissue RNAs of interface zones. However, these expressions were decreased in cultured interface cells. In midsubstance cells, the expression of COL1A1 gene was equally detected in both tissues and cultured cells. COL3A1 gene expression was maintained in cultured midsubstance cells. These results indicated that the phenotypes of both ACL cells were changed by cultured conditions, especially in the interface cells. After mechanical stretch, the COL1A1 expression of midsubstance and interface cells were stimulated up to 6 and 14-fold levels of each non-stretched control, respectively. The COL3A1 expressions were also enhanced up to 1.8-fold level of controls by stretching treatment in both cells. Integrin alphaVbeta3 was shifted to the peripheral edge of cells by stretching treatment. In addition, mechanical stretch changed the integrin alphaVbeta3-dependent stress fiber formation in both ACL cells. The functional blocking of integrin alphaVbeta3 inhibited stretch-activated COL1A1 and COL3A1 expressions. However, the functional blocking of integrin alpha5 did not suppress the stretch-induced COL1A1 and COL3A1 expressions in both ACL cells. Cultured interface cells loose their phenotypes in collagen gene expressions. However, mechanical stretch reproduces the expression of COL1A1 and COL3A1 genes in cultured ACL cells. The present study demonstrated that stretch-activated collagen gene expressions depend on the integrin alphaVbeta3-mediated cellular adhesions.
The objective of this study was to investigate the incidence of steroid-induced osteonecrosis (ON) among male and female rabbits. Forty-seven adult rabbits (male, n = 24; female, n = 23) were injected once intramuscularly into the right gluteus medius muscle with 20 mg/kg of methylprednisolone acetate. Hematological examinations were performed just before and at 1 and 2 weeks after the corticosteroid injection. Two weeks after the injection, both femora and humeri were histopathologically examined for the presence of ON, and the bone marrow fat cells were examined morphologically.Introduction
Methods
ROBODOC is a well known tool for a computer assisted arthroplasty. However, the incision tends to enlarge with the system because of the restriction of range of motion. We have developed the robot system for minimally invasive arthroplasty. This report shows the accuracy of our system composed of original planning software, navigation and bone cutting robot. We took the DICOM data of cadaver knees from computed tomography. The data were transferred to the workstation for planning. Matching points for registration and cutting planes were determined on the planning software. Cutting tool was the 6th robot which was able to recognize the locations of its apex and the cadaver knee with navigation system. We made five planes for TKA and two planes for UKA on femur. Then we made one plane on tibia. We evaluated the accuracy by measurement the location of cutting plane under navigation system and by CT data. The registration errors of femur and tibia were less than 1.0mm about cadaver knees. The errors of cutting planes were 1.3 mm about the distal end of femur and 0.5 mm about the proximal end of tibia. The accuracies of the angles of cutting planes were 1.9 degrees and 0.8 degrees compared to the mechanical axis. The errors of anterior and posterior plane of femur were increased compared to the distal plane. It was because the accuracy of registration were correct in axial direction but was not satisfied in rotational direction. The error was considered by the location of points which decided the rotation alignment. We will make effort to minimize the errors of registration and put it into practical use as soon as possible.
