Magnetic Resonance Imaging Score and Classification System (AMADEUS) for Assessment of Preoperative Cartilage Defect Severity.
ABSTRACT: Objective To design a simple magnetic resonance (MR)-based assessment system for quantification of osteochondral defect severity prior to cartilage repair surgery at the knee. Design The new scoring tool was supposed to include 3 different parameters: (1) cartilage defect size, (2) depth/morphology of the cartilage defect, and (3) subchondral bone quality, resulting in a specific 3-digit code. A clearly defined numeric score was developed, resulting in a final score of 0 to 100. Defect severity grades I through IV were defined. For intra- and interobserver agreement, defects were assessed by 2 independent readers on preoperative knee MR images of n = 44 subjects who subsequently received cartilage repair surgery. For statistical analyses, mean values ± standard deviation (SD), interclass correlation coefficients (ICC), and linear weighted kappa values were calculated. Results The mean total Area Measurement And DEpth & Underlying Structures (AMADEUS) score was 48 ± 24, (range, 0-85). The mean defect size was 2.8 ± 2.6 cm2. There were 36 of 44 full-thickness defects. The subchondral bone showed defects in 21 of 44 cases. Kappa values for intraobserver reliability ranged between 0.82 and 0.94. Kappa values for interobserver reliability ranged between 0.38 and 0.85. Kappa values for AMADEUS grade were 0.75 and 0.67 for intra- and interobserver agreement, respectively. ICC scores for the AMADEUS total score were 0.97 and 0.96 for intra- and interobserver agreement, respectively. Conclusions The AMADEUS score and classification system allows reliable severity encoding, scoring and grading of osteochondral defects on knee MR images, which is easily clinically applicable in daily practice.
Project description:Joint trauma is predisposing to the incidence of osteoarthritis (OA) of the knee. There is a limited knowledge on the impact of posttraumatic osteochondral defects on the whole joint. This study was designed to define a critical size osteochondral defect in the knee of rats and to investigate a possible association between osteochondral defects and degeneration of the surrounding joint surface.Cylindrical osteochondral defects of different sizes were created in the knee joint of rats. The natural course of these lesions was studied by macroscopic observation, histology, and immunohistochemistry. Gene expression of the articular cartilage surrounding the defects in vivo and of articular chondrocytes cultured in vitro in IL1? and fibroblast growth factor 2 (FGF2) supplemented media was evaluated by quantitative polymerase chain reaction (qPCR).In defects of 0.9 mm diameter, spontaneous joint surface healing was observed but also upward advancing of the subchondral bone plate at 16 weeks. Larger 1.4 mm diameter defects were critical size, not resulting in successful healing at any time point. Importantly, the articular cartilage surrounding the defects expressed FGF2 and IL1?, but not ACAN and Col2. Chondrocytes cultured in IL1? and FGF2 supplemented media lost the natural fibroblast growth factor receptors - FGFr1/FGFr3 balance and showed decreased viability.A critical size osteochondral defect was defined as 1.4 mm in diameter in rat. Subchondral bone plate advancement occured rapidly. The articular cartilage surrounding osteochondral defects showed catabolic activity with expression of IL1?, FGF2 and a disturbed FGFr1/FGFr3 balance, potentially initiating a process of early osteoarthritic disease.
Project description:Osteochondral defects of the knee are highly common, cause significant pain, and reduce function. Standard articular cartilage repair treatments include microfracture alone or in conjunction with subchondroplasty or CarGel (chitosan-based scaffold) application (Piramal Life Sciences). Combining such cartilage regenerative techniques with microfracture yields better long-term outcomes than microfracture alone. The purpose of this Technical Note was to describe the surgical technique of applying CarGel after subchondroplasty and microfracture to repair a medial femoral knee osteochondral defect.
Project description:Surgical articular cartilage repair therapies for cartilage defects such as osteochondral autograft transfer, autologous chondrocyte implantation (ACI) or matrix associated autologous chondrocyte transplantation (MACT) are becoming more common. MRI has become the method of choice for non-invasive follow-up of patients after cartilage repair surgery. It should be performed with cartilage sensitive sequences, including fat-suppressed proton density-weighted T2 fast spin-echo (PD/T2-FSE) and three-dimensional gradient-echo (3D GRE) sequences, which provide good signal-to-noise and contrast-to-noise ratios. A thorough magnetic resonance (MR)-based assessment of cartilage repair tissue includes evaluations of defect filling, the surface and structure of repair tissue, the signal intensity of repair tissue and the subchondral bone status. Furthermore, in osteochondral autografts surface congruity, osseous incorporation and the donor site should be assessed. High spatial resolution is mandatory and can be achieved either by using a surface coil with a 1.5-T scanner or with a knee coil at 3 T; it is particularly important for assessing graft morphology and integration. Moreover, MR imaging facilitates assessment of complications including periosteal hypertrophy, delamination, adhesions, surface incongruence and reactive changes such as effusions and synovitis. Ongoing developments include isotropic 3D sequences, for improved morphological analysis, and in vivo biochemical imaging such as dGEMRIC, T2 mapping and diffusion-weighted imaging, which make functional analysis of cartilage possible.
Project description:Knee cartilage or osteochondral lesions are common and challenging injuries. To date, most symptomatic lesions warrant surgical treatment. We present two cases of patients with knee osteochondral defects treated with a one-step surgical procedure consisting of an autologous-based matrix composed of healthy hyaline cartilage chips, mixed plasma poor-rich in platelets clot, and plasma rich in growth factors (PRGF). Both patients returned to playing soccer at the preinjury activity level and demonstrated excellent defect filling in both magnetic resonance imaging and second-look arthroscopy (in one of them). The use of a clot of autologous plasma poor in platelets with healthy hyaline cartilage chips and intra-articular injection of plasma rich in platelets is an effective, easy, and cheap option to treat knee cartilage injuries in young and athletic patients.
Project description:Focal articular cartilage injuries in the knee are common and can cause severe morbidity and reduced function. The articular cartilage is avascular and has limited ability to heal, and hence, patients with cartilage injuries have increased risk of progressing to osteoarthritis. Most of the cartilage injuries are located on the femoral condyles. Engaging focal cartilage injuries involving the trochlea are challenging because of the morbidity caused by these injuries and the limited treatment options. Osteochondral allograft transplantation is emerging as a promising treatment for full-thickness articular cartilage defects. Recent studies have reported high success rates with the use of osteochondral allografts. This article reports our technique of osteochondral allograft transplantation for the treatment of a focal full-thickness defect of the trochlea.
Project description:We treated 49 patients with recurrent patellar dislocations or persistent patellar subluxations. Chondral defects were graded according to the International Cartilage Repair Society (ICRS). Thirty patients (group I) had chondral defects grade I or II, and 19 patients (group II) had chondral defects grade III or IV. All patients were treated with proximal and distal realignment of the knee extensor mechanism, but group II also had a simultaneous autologous osteochondral grafting of the chondral defect. Patients were followed for 2 years and clinically assessed using the Marshall score comparing the two groups. Apart from a slower recovery in group II, the clinical and functional results were almost the same at the final follow-up.
Project description:Robust preclinical test methods involving tribological simulations are required to investigate and understand the tribological function of osteochondral repair interventions in natural knee tissues. The aim of this study was to investigate the effects of osteochondral allograft implantation on the local tribology (friction, surface damage, wear and deformation) of the tissues in the natural knee joint using a simple geometry, reciprocating pin-on-plate friction simulator. In addition, the study aimed to assess the ability of osteochondral grafts to restore a low surface damage, deformation and wear articulation when compared to the native state. A method was developed to characterise and quantify surface damage wear and deformation of the opposing cartilage-bone pin surface using a non-contacting optical profiler (Alicona Infinite Focus). Porcine 12?mm diameter cartilage-bone pins were reciprocated against bovine cartilage-bone plates that had 6?mm diameter osteochondral allografts, cartilage defects or stainless steel pins (positive controls) inserted centrally. Increased levels of surface damage with changes in geometry were not associated with significant increases in the coefficient of dynamic friction. Significant damage to the opposing cartilage surface was observed in the positive control groups. Cartilage damage, deformation and wear (as measured by change in geometry) in the xenograft (2.4?mm3) and cartilage defect (0.99?mm3) groups were low and not significantly different (p?>?0.05) compared to the negative control in either group. The study demonstrated the potential of osteochondral grafts to restore the congruent articular surface and biphasic tribology of the natural joint. An optical method has been developed to characterise cartilage wear, damage and deformation that can be applied to the tribological assessment of osteochondral grafts in a whole natural knee joint simulation model.
Project description:BACKGROUND:Osteochondral defects mostly occur as a result of trauma or articular degeneration. The poor regenerative ability of articular cartilage remains osteochondral defects are a tricky problem to deal with. The modern treatment strategies mainly focus on cartilage tissue engineering with bioactive materials. In this study, we aimed to develop icariin conditioned serum (ICS) together with hyaluronic acid (HA) and determine their ability in reparing osteochondral tissue in a critical-sized defect in rabbit knees. METHODS:Primary chondrocytes were incubated with serum conditioned with icariin at different concentrations, then cell proliferation rates and glycosaminoglycan (GAG) secretion were detected. Rabbits were treated with intra-articular injection of 0.5 mL normal saline (NS), ICS, HA and ICS + HA in the right knee joint, respectively. ICRS scores were used to assess the macroscopic cartilage regeneration. Histological and immunohistochemical analysis including H&E, Safranin O, toluidine blue and collagen II staining were used to determine the repair of cartilage and the regeneration of chondrocytes. RESULTS:Icariin at a low dose of 0.94 g/kg was identified to have significantly promoted the proliferation of chondrocytes and enhance the secretion of GAG. Femoral condyle from rabbits treated by ICS together with HA was observed to be integrated with native cartilage and more subchondral bone regeneration. ICS together with HA could promote repair of the cartilage defect and increase the neoformation of cartilage. CONCLUSIONS:These results demonstrated the potential of ICS combined with HA to promote reparative response in cartilage defects and the possible application in bioactive material based cartilage regeneration therapies.
Project description:Articular cartilage damage of the knee can cause severe morbidity. Owing to its avascular nature, articular cartilage has limited potential for self-healing and increased propensity to progress to osteoarthritis. Treatment of large, full-thickness cartilage defects is still a challenge for orthopaedic surgeons but has recently achieved high success rates with the use of osteochondral allografts. This article details our technique of osteochondral allograft transplantation for the treatment of articular cartilage defects of the knee.
Project description:BACKGROUND:Osteochondral defects caused by an acute traumatic injury or articular degeneration remains difficult to be manipulated. Repair of articular defects is still a great challenge for both tissue engineers and orthopedic surgeons. Therefore, combination of biomaterials with cartilage promotive drugs is well worth being developed to support the regeneration of both cartilage and subchondral bone. METHODS:Rabbits undergoing osteochondral defect surgery were intrarticularly injected with icariin-conditioned serum (ICS), chitosan (CSSH) and combination of ICS with CSSH, respectively. Gait analysis was performed using VICON motion capture system. ICRS score and immunohistochemical (IHC) analysis including H&E, Safranin O, toluidine blue and collagen II staining was employed to evaluate macroscopic cartilage regeneration and determine the morphologic repair of cartilage. RESULTS:Rabbits with the treatment of ICS or CSSH alone showed mild improvement in hopping time and range of joint angles while ICS-CSSH group exhibited longer jumping time and larger range of joint angles. In addition, femoral condyle in ICS-CSSH rabbits could be seen with more native cartilage and subchondral bone regeneration in both macroscopic observation and IHC analysis. CONCLUSION:ICS combined with CSSH could promote the repair of osteochondral defect in rabbit knees. Combination of biomaterials with cartilage promotive drugs may ultimately have profound implications in the management of cartilage defect.