Aseptic loosening of the acetabular component continues to be the most common indication for revision of total hip replacements in younger patients. Early in the evolution of the cemented hip, arthroplasty surgeons switched from removal to retention of the acetabular
In a prospective, controlled clinical study we randomised 50 patients with primary coxarthrosis into either removal or retention of the
Aims. Therapeutic agents that prevent chondrocyte loss, extracellular matrix (ECM) degradation, and osteoarthritis (OA) progression are required. The expression level of epidermal growth factor (EGF)-like repeats and discoidin I-like domains-containing protein 3 (EDIL3) in damaged human cartilage is significantly higher than in undamaged cartilage. However, the effect of EDIL3 on cartilage is still unknown. Methods. We used human cartilage plugs (ex vivo) and mice with spontaneous OA (in vivo) to explore whether EDIL3 has a chondroprotective effect by altering OA-related indicators. Results. EDIL3 protein prevented chondrocyte clustering and maintained chondrocyte number and SOX9 expression in the human cartilage plug. Administration of EDIL3 protein prevented OA progression in STR/ort mice by maintaining the number of chondrocytes in the hyaline cartilage and the number of matrix-producing chondrocytes (MPCs). It reduced the degradation of aggrecan, the expression of matrix metalloproteinase (MMP)-13, the Osteoarthritis Research Society International (OARSI) score, and bone remodelling. It increased the porosity of the
There is no optimal therapy to stop or cure chondral degeneration in osteoarthritis (OA). Beside cartilage, subchondral bone is involved. The often sclerotic bone is mechanically less solid which in turn influences negatively chondral quality. Microfracturing as therapeutic technique aims to enhance bone quality but is applied only in smaller cartilage lesions. The osteoproliferative properties of Magnesium (Mg) have been shown repeatedly1-3. The present study examined the influence of micro-scaled Mg cylinders compared to sole drilling in an OA model. Ten New Zealand White rabbits underwent anterior crucial ligament transection. During 12 weeks after surgery, the animals developed OA as previously described4. In a second surgery, half of the animals received 20 drill holes (ø 0.5mm) and the other half received 20 drill holes, which were additionally filled with one Mg cylinder each. Extracapsular plication was performed in all animals. During the follow-up of 8 weeks three µ-computed tomographic (µCT) scans were performed: immediately after surgery and after four and eight weeks. Changes of bone volume, trabecular thickness and bone density were calculated and compared. µCT evaluation showed an increase in bone volume and trabecular thickness in both groups. This increase was significantly higher in rabbits which received Mg cylinders showing thrice as high values for both parameters (bone volume: Mg group +44.5%, drilling group +15.1%, p≤0.025; trabecular thickness: Mg group +53.2%, drilling group +16.9%, p≤0.025). Also bone density increased in both groups, but on a distinctly lower level and with no significant difference. Although profound higher bone volume was found after implantation of Mg cylinders, µCT showed similar levels of bone density indicating adequate bone quality in this OA model. Macroscopic and histological evaluation of cartilage condition have to reveal possible impact on OA progression. Additionally, current examination implement different alloys and influence on lameness.
Aims. This study aimed to define the histopathology of degenerated humeral head cartilage and synovial inflammation of the glenohumeral joint in patients with omarthrosis (OmA) and cuff tear arthropathy (CTA). Additionally, the potential of immunohistochemical tissue biomarkers in reflecting the degeneration status of humeral head cartilage was evaluated. Methods. Specimens of the humeral head and synovial tissue from 12 patients with OmA, seven patients with CTA, and four body donors were processed histologically for examination using different histopathological scores. Osteochondral sections were immunohistochemically stained for collagen type I, collagen type II, collagen neoepitope C1,2C, collagen type X, and osteocalcin, prior to semiquantitative analysis. Matrix metalloproteinase (MMP)-1, MMP-3, and MMP-13 levels were analyzed in synovial fluid using enzyme-linked immunosorbent assay (ELISA). Results. Cartilage degeneration of the humeral head was associated with the histological presentation of: 1) pannus overgrowing the cartilage surface; 2) pores in the
Osteoarthritis (OA) is an inflammatory disease affecting the complete synovial joint including the cartilage layer and the
Many factors have been reported to affect the functional survival of OCA transplants, including chondrocyte viability at time of transplantation, rate and extent of allograft bone integration, transplantation techniques, and postoperative rehabilitation protocols and adherence. The objective of this study was to determine the optimal subchondral bone drilling technique by evaluating the effects of hole diameter on the material properties of OCAs while also considering total surface area for potential biologic benefits for cell and vascular ingrowth. Using allograft tissues that would be otherwise discarded in combination with deidentified diagnostic imaging (MRI and CT), a model of a large shell osteochondral allograft was recreated using LS-PrePost and FEBio based on clinically relevant elastic material properties for cortical bone, trabecular bone, cartilage, and hole ingrowth tissue. The 0.8 mesh size model consisted of 4 mm trabecular bone, 4 mm cortical bone, and 3 mm cartilage sections that summed to a cross-sectional area of 1600 mm2 (40 mm x 40 mm). Holes were modeled to be 4mm deep in relation to clinical practice where holes are drilled from the deep margin of subchondral trabecular bone to the cortical
Despite the growing success of OCA transplantation in treating large articular cartilage lesions in multiple joints, revisions and failures still occur. While preimplantation subchondral drilling is intended to directly decrease allograft bioburden and has been associated with significant improvements in outcomes after OCA transplantation, the effects of size, number, and spacing of subchondral bone drill sites have not been fully evaluated. This study aimed to investigate the effects of drill size with or without pulse-lavage of OCA subchondral bone by quantifying remnant marrow elements using histomorphometry. With IRB and ACUC approvals, human and canine OCAs were acquired for research purposes. Portions of human tibial plateau OCAs acquired from AATB-certified tissue banks that would otherwise be discarded were recovered and sectioned into lateral and medial hemiplateaus (n=2 each) with a thickness of 7 mm. Canine femoral condyles and tibial plateaus were split into lateral and medial components with a thickness of 7 mm (n=8). Using our clinical preimplantation preparation protocol, holes were drilled into the subchondral bone of each condyle and hemiplateau OCA using either 1.6 mm OD or 3.2 mm OD drill bits from the cut surface to the cortical
Purpose:. To develop a method for depth-wise analysis of subchondral bone that considers the gradient of bone volume, density and organization between the articular surface and the marrow cavity. To understand the interplay between subchondral bone changes and extrinsic cartilage repair after microfracture. Method: Since 30% of patients fail microfracture for contained chondral lesions, our hypothesis was that early subchondral sclerosis increases compaction of bone around microfracture holes, leading to failed cartilage repair. Human osteochondral segments from the knee joint were characterized macroscopically using the Outerbridge score, then imaged at 45 micron resolution using microCT. Regions of interest (ROI) were chosen under normal cartilage and abnormal cartilage (Outerbridge Score=1). Routine Bone mineral density (BMD) analysis was performed on each ROI using GE MicroView™ analysis software. Additional depth-wise analysis of BMD was done by exporting each ROI was a density map, and calculating the mean, standard deviation and rate of change of BMD by slice in the vertical (coronal) plane. Plots of normal and early OA data by depth were compared. Microfracture holes were made in normal and sclerotic subchondral bone, and depth-wise measurements of subchondral compaction around the holes were made were made. Results: Bone under normal versus OA cartilage was very subtly different in microCT images, but ROI microCT analysis showed that the OA samples were more mineralized and contained more bone. Using the depth-wise analysis algorithm, automated detection and measurement of the
The micro-mechanical properties of complex biomaterials play an important role in tissue engineering and regenerative medicine, by regulating cellular processes and signalling. Local characterization of complex tissues while immersed in liquids proves to be very difficult to perform. We therefore present a method to derive viscoelastic micro-mechanical properties via non-destructive nano-indentation measurements in liquid. This technique is featured with a fiber-optical ferrule-top micro-machined force transducer, enabling a wide range of mechanical tests: from quasi-static experiments to derive elastic moduli, to step-response tests (e.g. creep, stress-relaxation), dynamic mechanical analysis (DMA) and constant strain rate tests to characterize sample viscoelastic behaviour. As a complex application we here present the osteochondral (OC) interface, which gradually ranges from hard and stiff bone regions towards softer and viscoelastic articular cartilage covering joint surface. The osteochondral plugs were collected from medial femoral condyle of cadaveric knees and measured at 37°C to mimic in-vivo physiological-like conditions. The stiffness of articular cartilage was 1.58±0.06 MPa, whereas
Bone marrow lesions (BMLs), identified by MRI, are defined as a region of cancellous bone with high T2 and low T1 signal intensity. They are associated with various knee pathologies including spontaneous osteonecrosis of the knee (SPONK), AVN, trauma (fracture and bone contusion), following arthroscopy and secondary to overuse (i.e., after completing a marathon). They also are commonly recognised in patients with knee OA (referred to as OA-BMLs) and their substantial importance in knee OA pathogenesis has been recently identified. Depending upon the etiology (i.e., bone contusion, overuse, etc.) of the BML, these lesions can be “acute” in nature and spontaneously resolve over time. However, OA-BMLs generally are considered to be a “chronic” condition and overtime they have been shown to often persist and increase in size. Retrieval studies following THA and TKA, in patients with a preoperatively identified BML, have greatly expanded our understanding of OA – BMLs and these investigations consistently identify the critical role subchondral bone plays in OA disease progression. Histologic, histochemical and mechanical studies of OA-BMLs demonstrate significant alternations from healthy subchondral bone. The effected bone contains regions where fibrous tissue has replaced cancellous bone, microfractures are present and vascularity is increased. There is an increased concentration of inflammatory mediators and the bone structural integrity is compromised. Standard radiographs of the knee correlate only modestly with patient symptoms, but conversely, the presence of an OA-BML is an extremely strong predictor of pain and knee joint dysfunction. Felson et al. reported this relationship. In a large group of patients with painful knee OA, 77.5% of these patients had a BML. Both the presence and size of the BML, following multiregression analysis, were significant predictors of knee pain severity. Additionally, likely secondary to inadequate
Long-term regeneration of cartilage defects treated with tissue engineering constructs often fails because of insufficient integration with the host tissue. We hypothesize that construct integration will be improved when implants actively interact with and integrate into the subchondral bone. Growth and Differentiation Factor 5 (GDF-5) is known to support maturation of chondrocytes and to enhance chondrogenic differentiation and hypertrophy of mesenchymal stromal cells (MSC). Therefore, we investigated whether GDF-5 is capable to stimulate endochondral ossification of MSC in vitro and in vivo and would, thus, be a promising candidate for augmenting fibrin glue in order to support integration of tissue engineering constructs into the
Joint surface restoration of deep osteochondral defects represents a significant unmet clinical need. Moreover, untreated lesions lead to a high rate of osteoarthritis. The current strategies to repair deep osteochondral defects such as osteochondral grafting or sandwich strategies combining bone autografts with ACI/MACI fail to generate long-lasting osteochondral interfaces. Herein, we investigated the capacity of juvenile Osteochondral Grafts (OCGs) to repair osteochondral defects in skeletally mature animals. With this regenerative model in view, we set up a new biological, bilayered, and scaffold-free Tissue Engineered (TE) construct for the repair of the osteochondral unit of the knee. Skeletally immature (5 weeks old) and mature (11 weeks old) Lewis rats were used. Cylindrical OCGs were excised from the intercondylar groove of the knee of skeletally immature rats and transplanted into osteochondral defects created in skeletally mature rats. To create bilayered TE constructs, micromasses of human periosteum-derived progenitor cells (hPDCs) and human articular chondrocytes (hACs) were produced in vitro using chemically defined medium formulations. These constructs were subsequently implanted orthotopically in vivo in nude rats. At 4 and 16 weeks after surgery, the knees were collected and processed for subsequent 3D imaging analysis and histological evaluation. Micro-computed tomography (µCT), H&E and Safranin O staining were used to evaluate the degree of tissue repair. Our results showed that the osteochondral unit of the knee in 5 weeks old rats exhibit an immature phenotype, displaying active subchondral bone formation through endochondral ossification, the absence of a tidemark, and articular chondrocytes oriented parallel to the articular surface. When transplanted into skeletally mature animals, the immature OCGs resumed their maturation process, i.e., formed new subchondral bone, partially established the tidemark, and maintained their Safranin O-positive hyaline cartilage at 16 weeks after transplantation. The bilayered TE constructs (hPDCs + hACs) could partially recapitulate the cascade of events as seen with the immature OCGs, i.e., the regeneration of the subchondral bone and the formation of the typical joint surface architecture, ranging from non-mineralized hyaline cartilage in the superficial layers to a progressively mineralized matrix at the interface with a new
The TruFit® plug is a cylindrical scaffold designed to bridge defects in articular cartilages. It is a porous structure with interconnected pores, which gives it the capability of providing a framework for the ingrowth new tissue and remodelling to articular cartilage and bone. The aim of this study was to assess the radiological incorporation of TruFit® Plugs using MRI. Between December 2007 & August 2009, 22 patients underwent treatment of a chondral or osteochondral lesion using one or more TruFit Plugs. At a minimum of 2 years, 10 patients (12 lesions) were MRI scanned and assessed with a modified MOCART Scoring system by an independent Consultant Musculoskeletal Radiologist. 8 patients were no longer contactable and 4 patients declined MRI as their knee was asymptomatic. 8 of 12 lesions showed congruent articular cartilage cover with a surface of a similar thickness and signal to the surrounding cartilage and reconstitution of the
Summary. In a rabbit model of early osteoarthritis, structural changes in femoral condyle cartilage were severer in the lateral compartment and preceded alterations in the underlying bone. In the medial compartment, altered bone properties occurred together with structural changes in cartilage. Introduction. Early osteoarthritic changes in cartilage have been previously studied through anterior cruciate ligament transection (ACLT) in rabbits. However, parallel changes in the structure of subchondral and trabecular bone at 4 weeks after ACLT are not known. Methods. Skeletally mature 14-month old New Zealand white rabbits (n=8) underwent ACLT in the left knee, while right knees were used as controls (CTRL). Femoral condyles (FCs) were harvested at 4 weeks after ACLT. INDENTATION TESTING. Stepwise stress-relaxation tests were performed on medial and lateral FC cartilage (100%/s ramp rate, 3×5% step, 15 min relaxation time). Sinusoidal loading was then applied (amplitude 4% of thickness, 1Hz, 4 cycles). Equilibrium (Eeq) and dynamic (Ed) moduli were derived from stress-relaxation and sinusoidal tests, respectively. STRUCTURAL ANALYSIS OF CARTILAGE. Polarised light microscopy (PLM) and digital densitometry (DD) were used to analyze the collagen orientation angle (COA) and proteoglycan content in the cartilage samples. STRUCTURAL ANALYSIS OF BONE. Distal compartments of FCs were scanned using a high-resolution µCT scanner (Skyscan 1172, Belgium) with an isotropic voxel size of 25 µm. µCT data were imported into Mimics (Materialise, Belgium) for segmentation. 2×2×4 mm. 3. volumes of interest (VOIs) were placed in weight-bearing regions of medial and lateral FCs.
1. Sixteen patients with articular cartilage erosions after slight injury have been described, as have the results of their treatment. 2. The clinical features of this rarely diagnosed condition are discussed. Attention is drawn to "articular crepitus" and "synovial crepitus" as useful physical signs in establishing the diagnosis. 3. A radiographic sign of localised subarticular osteoporosis is reported and discussed. 4. The surgical treatment used was either shaving of the affected area of cartilage or a combination of shaving with drilling of the
Osteoarthritis (OA) is mainly caused by ageing, strain, trauma, and congenital joint abnormalities, resulting in articular cartilage degeneration. During the pathogenesis of OA, the changes in subchondral bone (SB) are not only secondary manifestations of OA, but also an active part of the disease, and are closely associated with the severity of OA. In different stages of OA, there were microstructural changes in SB. Osteocytes, osteoblasts, and osteoclasts in SB are important in the pathogenesis of OA. The signal transduction mechanism in SB is necessary to maintain the balance of a stable phenotype, extracellular matrix (ECM) synthesis, and bone remodelling between articular cartilage and SB. An imbalance in signal transduction can lead to reduced cartilage quality and SB thickening, which leads to the progression of OA. By understanding changes in SB in OA, researchers are exploring drugs that can regulate these changes, which will help to provide new ideas for the treatment of OA. Cite this article:
Osteoarthritis (OA) is the most prevalent systemic musculoskeletal disorder, characterized by articular cartilage degeneration and subchondral bone (SCB) sclerosis. Here, we sought to examine the contribution of accelerated growth to OA development using a murine model of excessive longitudinal growth. Suppressor of cytokine signalling 2 (SOCS2) is a negative regulator of growth hormone (GH) signalling, thus mice deficient in SOCS2 ( We examined vulnerability of Aims
Methods
Purpose: To define the role of ACI in treatment of cartilage defects in the knee joint. Method: 106 articular cartilage defects in 79 knees of 77 patients were treated by ACI as described by Brittberg et al, 1994. 43.5% of the lesions involved the patella, 35.2% the femoral condyles, 16.7% the trochlea, and 4.6% the tibial condyles. 20% of knees had more than one defect. Associated biomechanical procedures were carried out in 88.7%. Results: 70 lesions in 58 knees and 56 patients were assessed arthroscopically 9 months after implantation; 4 eligible patients were not assessed. The average ICRS repair score (maximum 12) was as follows: tibial condyle 11.5, (4 defects); patella 11.3, (32 defects); femoral condyle 11.0, (23 defects) and trochlea 10.7, (11 defects). Synovitis was markedly reduced in all knees with well healed defects. Contraindications to ACI in this series were:. Non-contained defects,. Bi-polar lesions,. Patients greater than 45 years,. Uncorrected biomechanics,. Regional pain syndrome type 1,. Limited joint movement,. Defective
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