ABSTRACT
OBJECTIVE: Since the joint microenvironment and tissue homeostasis are highly dependent on synovial fluid, we aimed to compare the essential chondrocyte signaling signatures of non-osteoarthritic vs end-stage osteoarthritic knee synovial fluid. Moreover, we determined the phenotypic consequence of the distinct signaling patterns on articular chondrocytes. METHODS: Protein profiling of synovial fluid was performed using antibody arrays. Chondrocyte signaling and phenotypic changes induced by non-osteoarthritic and osteoarthritic synovial fluid were analyzed using a phospho-kinase array, luciferase-based transcription factor activity assays, and RT-qPCR. The origin of osteoarthritic synovial fluid signaling was evaluated by comparing the signaling responses of conditioned media from cartilage, synovium, infrapatellar fat pad and meniscus. Osteoarthritic synovial fluid induced pathway-phenotype relationships were evaluated using pharmacological inhibitors. RESULTS: Compared to non-osteoarthritic synovial fluid, osteoarthritic synovial fluid was enriched in cytokines, chemokines and growth factors that provoked differential MAPK, AKT, NFκB and cell cycle signaling in chondrocytes. Functional pathway analysis confirmed increased activity of these signaling events upon osteoarthritic synovial fluid stimulation. Tissue secretomes of osteoarthritic cartilage, synovium, infrapatellar fat pad and meniscus activated several inflammatory signaling routes. Furthermore, the distinct pathway signatures of osteoarthritic synovial fluid led to accelerated chondrocyte dedifferentiation via MAPK/ERK signaling, increased chondrocyte fibrosis through MAPK/JNK and PI3K/AKT activation, an elevated inflammatory response mediated by cPKC/NFκB, production of extracellular matrix-degrading enzymes by MAPK/p38 and PI3K/AKT routes, and enabling of chondrocyte proliferation. CONCLUSION: This study provides the first mechanistic comparison between non-osteoarthritic and osteoarthritic synovial fluid, highlighting MAPKs, cPKC/NFκB and PI3K/AKT as crucial OA-associated intracellular signaling routes.
Subject(s)
Cartilage, Articular , Chondrocytes , Chondrocytes/metabolism , Synovial Fluid/metabolism , Cartilage, Articular/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Cells, Cultured , PhenotypeABSTRACT
PURPOSE: The purpose of this first-in-human study was to evaluate the effect of a polycarbonate anatomical meniscus prosthesis system, including the surgical procedure, on knee pain and describe potential adverse events in patients with post-meniscectomy pain syndrome. METHODS: Eleven patients with post-meniscectomy pain syndrome and limited underlying cartilage damage were enrolled in the study. Five received a medial polycarbonate urethane meniscus prosthesis which was clicked onto 2 titanium screws fixated at the native horn attachments on the tibia. The KOOS score was planned to be collected at baseline and at 3, 6, 12 and 24 months following the intervention including radiographs at 6, 12 and 24 months. MRI scans were repeated after 12 and 24 months. RESULTS: The surgical technique to select an appropriately sized implant and correct positioning of the fixation screws and meniscus prosthesis onto the tibia was demonstrated to be feasible and reproducible. Inclusion stopped after 5 patients because of serious adverse device-related events. All patients reported knee joint stiffness and slight effusion in their knee at 6 months follow-up. In 3 patients the implant was removed because of implant failure and in 1 patient the implant was removed because of persistent pain and extension limitation. In none of the patients did the KOOS score improve in the first 6 months after surgery. However, in the patient who still has the implant in situ, PROMs started to improve 1 year after surgery and this improvement continued through 2 years of follow-up. The KOOS Pain, symptoms and ADL were close to the maximal 100 points. KOOS QoL and sport did improve but remained suboptimal. CONCLUSION: This first version of the meniscus prosthesis led to impaired knee function and failed in four out of five patients. The patients where the prosthesis was removed were salvable and the PROMs returned to pre-study levels. The results in the patient where the device is still in place are promising. LEVEL OF EVIDENCE: Level II.
Subject(s)
Joint Prosthesis , Menisci, Tibial , Humans , Menisci, Tibial/diagnostic imaging , Menisci, Tibial/surgery , Quality of Life , Knee Joint/surgery , Pain , Treatment OutcomeABSTRACT
BACKGROUND: This study surveyed Dutch orthopedic surgeons on the management of cartilage defects in the knee and the adherence to the recently updated Dutch knee cartilage repair consensus statement (DCS). METHODS: A web-based survey was sent to 192 Dutch knee specialists. RESULTS: The response rate was 60%. Microfracture, debridement and osteochondral autografts are performed by the majority, 93%, 70% and 27% of respondents, respectively. Complex techniques are used by < 7%. Microfracture is mainly considered in defects 1-2 cm2 (by > 80%) but also in 2-3 cm2 (by > 40%). Concomitant procedures, e.g., malalignment corrections, are performed by 89%. Twenty-one percent of surgeons treat patients aged 40-60 years. Microfracture, debridement and autologous chondrocyte implantation are not considered to be highly affected by age > 40 years by any of the respondents (0-3%). Moreover, for the middle-aged there is a large spread in treatments considered. In case of loose bodies, the majority (84%) only performs refixation in the presence of attached bone. CONCLUSION: Small cartilage defects in ideal patients may be well treated by general orthopedic surgeons. The matter becomes complicated in older patients, or in case of larger defects or malalignment. The current study reveals some knowledge gaps for these more complex patients. Referral to tertiary centers might be indicated, as is stated by the DCS, and this centralization should enhance knee joint preservation. Since the data from present study are subjective, registration of all separate cartilage repair cases should fuel objective analysis of clinical practice and adherence to the DCS in the future.
Subject(s)
Cartilage Diseases , Cartilage, Articular , Fractures, Stress , Orthopedic Procedures , Orthopedic Surgeons , Middle Aged , Humans , Aged , Cartilage, Articular/surgery , Knee Joint/surgery , Cartilage Diseases/surgery , Orthopedic Procedures/methods , Transplantation, Autologous/methods , Surveys and Questionnaires , Chondrocytes/transplantationABSTRACT
OBJECTIVE: Early and non-invasive detection of osteoarthritis (OA) is required to enable early treatment and monitoring of interventions. Some of the earliest signs of OA are the change in proteoglycan and collagen composition. The aim of this study is to establish the relations between quantitative magnetic resonance imaging (MRI) and biochemical concentration and organization in knee articular cartilage. METHODS: A preregistered systematic literature review was performed using the databases PubMed and Embase. Papers were included if quantitative MRI and a biochemical assay or polarized light microscopy (PLM) was performed on knee articular cartilage, and a quantified correlation was described. The extracted correlations were pooled using a random effects model. RESULTS: 21 papers were identified. The strongest pooled correlation was found for delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) vs proteoglycan concentration (r = 0.59). T1ρ relaxation times are inversely correlated to proteoglycan concentration (r = -0.54). A weak correlation between T2 relaxation times and proteoglycans was found (r = -0.38). No correlation between T2 relaxation time and collagen concentration was found (r = -0.02). A heterogeneous set of correlations between T2 relaxation times and PLM were identified, including strong correlations to anisotropy. CONCLUSION: DGEMRIC measures are significantly correlated to proteoglycan concentration. The needed contrast agent is however a disadvantage; the T1ρ sequence was found as a non-invasive alternative. Remarkably, no correlation was found between T2 relaxation times and collagen concentration. T2 relaxation times is related to organization, rather than concentration of collagen fibers. PROSPERO ID: CRD42020168337.
Subject(s)
Cartilage, Articular , Osteoarthritis, Knee , Osteoarthritis , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/pathology , Collagen , Humans , Knee Joint/diagnostic imaging , Knee Joint/pathology , Magnetic Resonance Imaging/methods , Osteoarthritis/pathology , Osteoarthritis, Knee/diagnostic imaging , Osteoarthritis, Knee/pathology , ProteoglycansABSTRACT
OBJECTIVE: For many proteins from osteoarthritic synovial fluid, their intra-articular tissue of origin remains unknown. In this study we performed comparative proteomics to identify osteoarthritis-specific and joint tissue-dependent secreted proteins that may serve as candidates for osteoarthritis biomarker development on a tissue-specific basis. DESIGN: Protein secretomes of cartilage, synovium, Hoffa's fat pad and meniscus from knee osteoarthritis patients were determined using liquid chromatography tandem mass spectrometry, followed by label-free quantification. Validation of tissue-dependent protein species was conducted by ELISA on independent samples. Differential proteomes of osteoarthritic and non-osteoarthritic knee synovial fluids were obtained via similar proteomics approach, followed by ELISA validation. RESULTS: Proteomics revealed 64 proteins highly secreted from cartilage, 94 from synovium, 37 from Hoffa's fat pad and 21 from meniscus. Proteomic analyses of osteoarthritic vs non-osteoarthritic knee synovial fluid revealed 70 proteins with a relatively higher abundance and 264 proteins with a relatively lower abundance in osteoarthritic synovial fluid. Of the 70 higher abundance proteins, 23 were amongst the most highly expressed in the secretomes of a specific intra-articular tissue measured. Tissue-dependent release was validated for SLPI, C8, CLU, FN1, RARRES2, MATN3, MMP3 and TNC. Abundance in synovial fluid of tissue-dependent proteins was validated for IGF2, AHSG, FN1, CFB, KNG and C8. CONCLUSIONS: We identified proteins with a tissue-dependent release from intra-articular human knee OA tissues. A number of these proteins also had an osteoarthritis-specific abundance in knee synovial fluid. These proteins may serve as novel candidates for osteoarthritis biomarker development on a tissue-specific basis.
Subject(s)
Adipose Tissue/metabolism , Cartilage, Articular/metabolism , Menisci, Tibial/metabolism , Osteoarthritis, Knee/metabolism , Proteomics , Synovial Fluid/metabolism , Synovial Membrane/metabolism , Aged , Case-Control Studies , Female , Humans , Knee Joint/metabolism , Male , SecretomeABSTRACT
Osteoarthritis (OA) is one of the most common musculoskeletal diseases, characterized by the progressive deterioration of articular cartilage. Although the disease has been well studied in the past few years, the endogenous metabolic composition and more importantly the spatial information of these molecules in cartilage is still poorly understood. Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) has been previously used for the investigation of the bimolecular distribution of proteins and lipids through the in situ analysis of cartilage tissue sections. MALDI-MSI as a tool to detect metabolites remains challenging, as these species have low abundance and degrade rapidly. In this work, we present a complete methodology, from sample preparation to data analysis for the detection of endogenous metabolites on cartilage by MSI. Our results demonstrate for the first time the ability to detect small molecules in fragile, challenging tissues through an optimized protocol, and render MSI as a tool towards a better understanding of OA.
Subject(s)
Cartilage, Articular/diagnostic imaging , Metabolomics , Osteoarthritis/diagnostic imaging , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Cartilage, Articular/metabolism , Humans , Osteoarthritis/metabolism , Specimen HandlingABSTRACT
OBJECTIVE: The Hoffa's fat pad (HFP) is an intra-articular adipose tissue which is situated under and behind the patella. It contains immune cells next to adipocytes and secretes inflammatory factors during osteoarthritis (OA). In this study, we compared the release profile of prostanoids, which are involved in inflammation, of HFP from OA patients vs patients with a focal cartilage defect (CD) without evidence for OA on MRI and investigated the prostanoid modulatory anti-inflammatory action of celecoxib on HFP. DESIGN: Prostanoid release was analyzed in conditioned medium of HFP explant cultures from 17 osteoarthritic patients and 12 CD patients, in the presence or absence of celecoxib. Furthermore, gene expression of COX enzymes and expression of genes indicative of a pro-inflammatory or anti-inflammatory phenotype of HFP was analyzed. RESULTS: Prostanoid release by HFP from knee OA patients clustered in two subgroups with high and low prostanoid producers. HFP from high prostanoid producers released higher amounts of PGE2, PGF2α and PGD2 compared to HFP from CD patients. PGE2 release by OA HFP was positively associated with expression of genes known to be expressed by M1 macrophages, indicating a role for macrophages. Celecoxib modulated prostanoid release by HFP, and also modulated the inflammation ratio towards a more favorable anti-inflammatory M2 phenotype, most effectively in patients with higher prostanoid release profiles. CONCLUSION: In knee OA patients with inflamed HFP's, celecoxib may exert positive effects in the knee joint via decreasing the release of prostanoids produced by the HFP and by favorably modulating the anti-inflammatory marker expression in HFP.
Subject(s)
Adipose Tissue/metabolism , Celecoxib/pharmacology , Inflammation/metabolism , Magnetic Resonance Imaging/methods , Osteoarthritis, Knee/therapy , Prostaglandins/metabolism , Adipose Tissue/pathology , Adult , Aged , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Female , Humans , Male , Middle Aged , Osteoarthritis, Knee/diagnosis , Osteoarthritis, Knee/metabolismABSTRACT
OBJECTIVE: On a population level, the incidence of knee prostheses (KPs) has increased, but excess health care costs per patient, compared to matched controls without a KP, in the years surrounding these procedures and their determinants are largely unknown. We therefore aimed to provide estimates of age- and sex-specific incidence of KPs, revision KPs, and prosthesis complications in patients with knee osteoarthritis (OA) and to determine excess health care costs in the years surrounding surgery compared with matched controls. METHODS: All KPs in OA patients in the Achmea Health Database were identified as well as up to four controls. Incidence rates of KPs, revisions, and complications from 2006 to 2013 were determined. Annual health care cost and excess costs (over matched controls) preceding, during, and after surgery were calculated and their determinants were evaluated. RESULTS: The increased incidence of KPs, revisions, and complications was strongest in younger age categories and men. The average costs per patient were relatively stable between 2006 and 2012. KP patient's annual health care costs increased towards the year of surgery. After surgery, costs decreased, but remained higher as compared to costs prior to surgery. High post-surgery costs were mainly associated with subsequent revisions or additional KPs, but costs were also higher in females, lower age categories, and lower social economic status. CONCLUSION: These results underscore the increasing burden and medical need associated with end-stage OA, especially in younger age categories. Improvement of guidelines tailored to individual patient groups aimed at avoiding complications and revisions is required to counteract this increasing burden.
Subject(s)
Arthroplasty, Replacement, Knee/economics , Health Care Costs/statistics & numerical data , Osteoarthritis, Knee/surgery , Adolescent , Adult , Age Distribution , Age Factors , Aged , Aged, 80 and over , Arthroplasty, Replacement, Knee/adverse effects , Arthroplasty, Replacement, Knee/methods , Arthroplasty, Replacement, Knee/statistics & numerical data , Case-Control Studies , Databases, Factual , Female , Humans , Incidence , Male , Middle Aged , Netherlands/epidemiology , Osteoarthritis, Knee/economics , Postoperative Complications/economics , Postoperative Complications/epidemiology , Reoperation/economics , Reoperation/statistics & numerical data , Sex Distribution , Young AdultABSTRACT
PURPOSE: Patient-specific instrumentation (PSI) is a technique to plan and position the prosthesis components in unicompartmental knee arthroplasty (UKA) surgery. This study assesses whether the definitive component position in the frontal, sagittal and axial plane is according to the preoperative plan, based on the hypothesis that PSI is accurate. METHODS: Twenty-six patients who had PSI Oxford UKA surgery were included prospectively. The component position in vivo was determined with a postoperative CT-scan and compared with the planned component position using MRI-based digital 3D imaging. Adjustments to the preoperative plan and implanted component sizes during surgery were recorded. RESULTS: Intraoperatively, no femoral adjustments were performed; 12 tibial re-resections were necessary. The median absolute deviation from the plan in degrees (range) in the frontal, sagittal and axial plane was 1.8° (- 1.5°-6.5°), 2.0° (- 6.5°-8.0°) and 1.0° (- 1.5°-5.0°) for the femoral component, and 2.5° (- 1.0°-6.0°), 3.0° (- 1.0°-5.0°) and 5.0° (- 6.5°-12.5°) for the tibial component. The femoral component is positioned 0.5 (- 1°-2.5°) mm more lateral and 0.8 (- 1.0°-2.5°) mm more anterior. The tibial component is positioned 2.0 (- 5.0-0.0) mm more lateral and 1.3 (- 3.0-6.0) mm more distal. The femoral and tibial default plans were changed four times (15.4%) and nine times (34.6%), respectively, before approval by the surgeon. CONCLUSION: PSI in Oxford UKA surgery is reliable and accurately translates the preoperative plan into the in vivo situation, except for the tibial rotational position. The preoperative planning is a crucial step in avoiding re-resections that can cause angular deviations in prosthesis position, especially in tibial component rotational position. It is advised to avoid re-resections and to consider this while planning the PSI procedure. LEVEL OF EVIDENCE: Prospective comparative study Level II.
Subject(s)
Arthroplasty, Replacement, Knee/instrumentation , Bone Malalignment/diagnostic imaging , Knee Prosthesis , Osteoarthritis, Knee/surgery , Surgery, Computer-Assisted/instrumentation , Tibia/surgery , Aged , Arthroplasty, Replacement, Knee/adverse effects , Arthroplasty, Replacement, Knee/methods , Bone Malalignment/physiopathology , Bone Malalignment/surgery , Female , Femur/physiopathology , Femur/surgery , Humans , Knee Joint/diagnostic imaging , Knee Joint/physiopathology , Knee Joint/surgery , Knee Prosthesis/adverse effects , Male , Middle Aged , Osteoarthritis, Knee/diagnostic imaging , Osteoarthritis, Knee/physiopathology , Prospective Studies , Reproducibility of Results , Rotation , Surgery, Computer-Assisted/adverse effects , Surgery, Computer-Assisted/methods , Tibia/physiopathologyABSTRACT
Many studies have reported on the effects of cyclooxygenase-2 (COX-2) inhibition on osteogenesis. However, far less is known about the effects of COX-2 inhibition on chondrogenic differentiation. Previous studies conducted by our group show that COX-2 inhibition influences in vitro chondrogenic differentiation. Importantly, this might have consequences on endochondral ossification processes occurring in vivo, such as bone fracture healing, growth plate development and ectopic generation of cartilage. The goal of our study was to investigate, in vivo, the effect of COX-2 inhibition by celecoxib on the cartilaginous phase of three different endochondral ossification scenarios. 10 mg/kg/day celecoxib or placebo were orally administered for 25 d to skeletally-immature New Zealand White rabbits (n = 6 per group). Endochondral ossification during fracture healing of a non-critical size defect in the ulna, femoral growth plate and ectopically-induced cartilaginous tissue were examined by radiography, micro-computed tomography (µ-CT), histology and gene expression analysis. Celecoxib treatment resulted in delayed bone fracture healing, alterations in growth plate development and progression of mineralisation. In addition, chondrogenic differentiation of ectopically-induced cartilaginous tissue was severely impaired by celecoxib. In conclusion, we found that celecoxib impaired the chondrogenic phase of endochondral ossification.
Subject(s)
Celecoxib/pharmacology , Chondrogenesis/drug effects , Cyclooxygenase 2 Inhibitors/pharmacology , Osteogenesis/drug effects , Administration, Oral , Animals , Bone and Bones/diagnostic imaging , Bone and Bones/drug effects , Bone and Bones/metabolism , Cartilage/diagnostic imaging , Cartilage/drug effects , Cartilage/metabolism , Celecoxib/administration & dosage , Cell Differentiation/drug effects , Cell Differentiation/genetics , Chondrocytes/drug effects , Chondrocytes/metabolism , Chondrogenesis/physiology , Cyclooxygenase 2 Inhibitors/administration & dosage , Dinoprostone/metabolism , Fracture Healing/drug effects , Gene Expression/drug effects , Osteogenesis/physiology , Rabbits , X-Ray MicrotomographyABSTRACT
BACKGROUND: Despite growing evidence in the literature, there is still a lack of consensus regarding the use of the mobile-bearing (MB) design total knee arthroplasty (TKA). METHODS: In a prospective, comparative, randomised, single centre trial, 106 patients with end-stage osteoarthritis of the knee were randomised to either an MB or fixed-bearing (FB) group to receive posterior stabilised (PS)-TKA using a standard medial parapatellar approach and patellar resurfacing with follow-up (FU) for 5 years. The primary outcome was anterior knee pain (AKP) during the chair rise test and the stair climb test 5 years after surgery. The secondary outcome was the ability to rise from a chair and to climb stairs, range of motion (ROM), Knee Society Score (KSS), RAND-36 scores and radiological analysis of the patellar tilt. RESULTS: No statistically significant difference was found between the two groups at 5 years FU in terms of median AKP during the chair rise test and the stair climb test (p = 0.5 and p = 0.8, respectively). There was no significant difference in any of the other secondary outcome parameters between the groups at 5 years FU. CONCLUSION: A mobile-bearing TKA does not decrease AKP compared to fixed bearings. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT02892838 . LEVEL OF EVIDENCE: II.
Subject(s)
Arthroplasty, Replacement, Knee/instrumentation , Knee Prosthesis/adverse effects , Pain, Postoperative/etiology , Humans , Prospective StudiesABSTRACT
PURPOSE: Although fewer tibial radiolucent lines are observed in cementless Oxford unicompartmental knee arthroplasty (UKA) compared with cemented Oxford UKA, an independent comparative study on this topic is lacking. METHODS: In this multicentre retrospective study, a cohort of 60 consecutive cases of cementless Oxford UKA is compared with a cohort of 60 consecutive cases of cemented Oxford UKA. Radiolucent lines, survival, perioperative data and clinical results were compared. RESULTS: No complete tibial radiolucent lines were observed in either group. Seventeen per cent of partial tibial radiolucent lines were observed in the cementless group versus 21 % in the cemented group (n.s.). The percentage of tibial radiolucent zones was 4 versus 9 %, respectively (p = 0.036). Survival rates were 90 % at 34 months for the cementless group and 84 % at 54 months for the cemented group (n.s.). Mean operation time was 10 min shorter in the cementless group (p < 0.001), and clinical results were not significantly different. CONCLUSIONS: Although no significant differences in radiolucent lines were found between both groups, they appear to be more common in the cemented group. This confirms previous results from reports by prosthesis designers. The presence of radiolucent lines after cemented Oxford UKA does not correlate with clinical outcome or survival. LEVEL OF EVIDENCE: III.
Subject(s)
Arthroplasty, Replacement, Knee/methods , Knee Prosthesis , Osteoarthritis, Knee/surgery , Postoperative Complications/diagnostic imaging , Prosthesis Design , Tibia/diagnostic imaging , Aged , Aged, 80 and over , Bone Cements , Case-Control Studies , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Retrospective Studies , Treatment OutcomeABSTRACT
OBJECTIVE: To investigate associations of biochemical markers of joint metabolism and inflammation with minimum joint space width (JSW) and osteophyte area (OP area) of knees showing no or doubtful radiographic osteoarthritis (OA) and to investigate whether these differed between painful and non-painful knees. DESIGN: Serum (s-) and urinary (u-) levels of the cartilage markers uCTX-II, sCOMP, sPIIANP, and sCS846, bone markers uCTX-I, uNTX-I, sPINP, and sOC, synovial markers sPIIINP and sHA, and inflammation markers hsCRP and erythrocyte sedimentation rate (ESR) were assessed in subjects from CHECK (Cohort Hip and Cohort Knee) demonstrating Kellgren and Lawrence grade ≤1 OA on knee radiographs. Minimum JSW and OP area of these knees were quantified in detail using Knee Images Digital Analysis (KIDA). RESULTS: uCTX-II levels showed negative associations with minimum JSW and positive associations with OP area. sCOMP and sHA levels showed positive associations with OP area, but not with minimum JSW. uCTX-I and uNTX-I levels showed negative associations with minimum JSW and OP area. Associations of biochemical marker levels with minimum JSW were similar between painful and non-painful knees, associations of uCTX-II, sCOMP, and sHA with OP area were only observed in painful knees. CONCLUSIONS: In these subjects with no or doubtful radiographic knee OA, uCTX-II might not only reflect articular cartilage degradation but also endochondral ossification in osteophytes. Furthermore, sCOMP and sHA relate to osteophytes, maybe because synovitis drives osteophyte development. High bone turnover may aggravate articular cartilage loss. Metabolic activity in osteophytes and synovial tissue, but not in articular cartilage may be related to knee pain.
Subject(s)
Arthralgia/metabolism , Knee Joint/metabolism , Osteoarthritis, Knee/diagnostic imaging , Osteoarthritis, Knee/metabolism , Aged , Biomarkers/blood , Biomarkers/urine , Female , Humans , Male , Middle Aged , RadiographyABSTRACT
OBJECTIVE: Osteoarthritis (OA) is characterized by loss of cartilage and alterations in subchondral bone architecture. Changes in cartilage and bone tissue occur simultaneously and are spatially correlated, indicating that they are probably related. We investigated two hypotheses regarding this relationship. According to the first hypothesis, both wear and tear changes in cartilage, and remodeling changes in bone are a result of abnormal loading conditions. According to the second hypothesis, loss of cartilage and changes in bone architecture result from endochondral ossification. DESIGN: With an established bone adaptation model, we simulated adaptation to high load and endochondral ossification, and investigated whether alterations in bone architecture between these conditions were different. In addition, we analyzed bone structure differences between human bone samples with increasing degrees of OA, and compared these data to the simulation results. RESULTS: The simulation of endochondral ossification led to a more refined structure, with a higher number of trabeculae in agreement with the finding of a higher trabecular number in osteochondral plugs with severe OA. Furthermore, endochondral ossification could explain the presence of a "double subchondral plate" which we found in some human bone samples. However, endochondral ossification could not explain the increase in bone volume fraction that we observed, whereas adaptation to high loading could. CONCLUSION: Based on the simulation and experimental data, we postulate that both endochondral ossification and adaptation to high load may contribute to OA bone structural changes, while both wear and tear and the replacement of mineralized cartilage with bone tissue may contribute cartilage thinning.
Subject(s)
Adaptation, Physiological/physiology , Bone and Bones/pathology , Cartilage/pathology , Models, Biological , Osteoarthritis/pathology , Osteogenesis/physiology , Bone Remodeling/physiology , Chondrocytes/pathology , Finite Element Analysis , Humans , Ossification, Heterotopic/pathology , Weight-Bearing/physiologyABSTRACT
OBJECTIVE: Bone morphogenic protein (BMP)-2 and BMP-7 are clinically approved and their recombinant proteins are used for bone tissue regenerative purposes and widely evaluated for cartilage regeneration. Previous comparison of the in vitro chondrogenic characteristics of BMP-2 vs BMP-7 did not address hypertrophic differentiation and characterizing their chondrogenic properties with a focus in on chondrocyte hypertrophy was topic of investigation in this study. DESIGN: Equimolar concentrations of BMP-2 or BMP-7 were added to chondrogenic differentiating ATDC5, human bone marrow stem cells or rabbit periosteal explants. Expression of Col2a1, Sox9, Acan, Col10a1, Runx2, ALP, Mmp13, Mef2c and Bapx1/Nkx3.2 was determined by reverse transcription-quantitative PCR (RT-qPCR) and immunoblotting. Glycosaminoglycan content, cell proliferation capacity and ALP activity were analysed by colourimetric analyses. Expression of Bapx1/Nkx3.2 and Sox9 was targeted by transfection of target specific siRNA duplexes. RESULTS: BMP-2 dose-dependently increased chondrocyte hypertrophy during chondrogenic differentiation of progenitor cells, whereas BMP-7 acted hypertrophy-suppressive and chondro-promotive. Both BMPs did not influence cell proliferation, but they did increase total glycosaminoglycan content. In a candidate approach Bapx1/Nkx3.2 was found to be involved in the BMP-7 mediated suppression of chondrocyte hypertrophy in ATDC5 cells. CONCLUSIONS: BMP-2 and BMP-7 display opposing actions on the chondrogenic outcome of differentiating progenitor cells: BMP-2 acts a specific inducer of chondrocyte hypertrophy, while BMP-7 appears to increase or maintain chondrogenic potential and prevent chondrocyte hypertrophy. Our results pave the way for an application-dependent differential use of BMP-2 or BMP-7.
Subject(s)
Bone Morphogenetic Protein 2/pharmacology , Bone Morphogenetic Protein 7/pharmacology , Chondrocytes/drug effects , Stem Cells/drug effects , Animals , Bone Marrow Cells/drug effects , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Enlargement/drug effects , Cells, Cultured , Chondrocytes/cytology , Chondrocytes/pathology , Chondrogenesis/drug effects , Dose-Response Relationship, Drug , Homeodomain Proteins/physiology , Humans , Hypertrophy , Rabbits , Stem Cells/cytology , Transcription Factors/physiologyABSTRACT
OBJECTIVE: Three-dimensional (3D) cultures are widely used to redifferentiate chondrocytes. However, the rationale behind the choice for 3D above two-dimensional (2D) cultures is poorly systematically investigated and mainly based on mRNA expression and glycosaminoglycan (GAG) content. The objective was to determine the differential redifferentiation characteristics of human articular chondrocytes (HACs) in monolayer, alginate beads and pellet culture by investigating mRNA expression, protein expression, GAG content and cell proliferation. DESIGN: Dedifferentiated HACs from six individuals were redifferentiated in identical medium conditions for 7 days in monolayer, alginate beads or pellet culture. Read-out parameters were expression of chondrogenic and hypertrophic mRNAs and proteins, GAG content and cell proliferation. RESULTS: 3D cultures specifically expressed chondrogenic mRNAs [collagen type II (COL2A1), SRY (sex determining region Y)-box 9 (SOX9), aggrecan (ACAN)), whereas 2D cultures did not. Hypertrophic mRNAs (collagen type X (COL10A1), runt-related transcription factor 2 (RUNX2), matrix metalloproteinase 13 (MMP13), vascular endothelial growth factor A (VEGFA), osteopontin (OPN), alkaline phosphatase (ALP)) were highly increased in 2D cultures and lower in 3D cultures. Collagen type I (COL1A1) mRNA expression was highest in 3D cultures. Protein expression supports most of the mRNA data, although an important discrepancy was found between mRNA and protein expression of COL2A1 and SOX9 in monolayer culture, stressing on the importance of protein expression analysis. GAG content was highest in 3D cultures, whereas chondrocyte proliferation was almost specific for 2D cultures. CONCLUSIONS: For redifferentiation of dedifferentiated HACs, 3D cultures exhibit the most potent chondrogenic potential, whereas a hypertrophic phenotype is best achieved in 2D cultures. This is the first human study that systematically evaluates the differences between proliferation, GAG content, protein expression and mRNA expression of commonly used 2D and 3D chondrocyte culture techniques.
Subject(s)
Cartilage, Articular/cytology , Cell Dedifferentiation/physiology , Cell Differentiation/physiology , Chondrocytes/cytology , Chondrogenesis/physiology , Arthroplasty, Replacement, Knee , Cartilage, Articular/physiology , Cells, Cultured , Chondrocytes/physiology , Humans , Osteoarthritis, Knee/pathology , Osteoarthritis, Knee/surgeryABSTRACT
OBJECTIVE: To describe health care utilization (HCU) and predict analgesic use and health professional (HP) contact at baseline and 2 years in individuals with early symptomatic hip and/or knee osteoarthritis (OA). DESIGN: Baseline and two-year data on HCU of the 1002 participants from the multi-centre Cohort Hip & Cohort Knee study were used. Six forms of health care services were described: analgesic use, supplement use, contact with a General Practitioner (GP), contact with a HP, contact in secondary care, and alternative medicine use. Multivariable logistic regression was performed in order to identify predisposing, enabling and disease-related variables that predict analgesic use and HP contact at 2 years; treatment modalities of first choice in early OA. RESULTS: For the hip (n=170), the knee (n=414) and the hip and knee (n=418) group analgesic use (38%, 29% and 47%, respectively), contact with a GP (32%, 38% and 36%, respectively) and contact with a HP (26%, 18% and 20%, respectively), were reported most often at baseline. Contact with a GP significantly decreased, supplement use increased (to about one third), and other treatment modalities remained stable at 2 years. In all three groups, analgesic use at baseline was the strongest predictor for analgesic use at 2 years, whereas contact with a HP at baseline was the strongest predictor of contact with a HP after 2 years. Belonging to a first generation minority was a predisposing risk factor [Odds Ratio (95%-CI), 8.72 (1.55-48.97)] for analgesic use in the hip and knee group. CONCLUSIONS: In early OA, familiarity with HCU and other predisposing factors are, apart from disease-related factors strongly associated with HCU at 2 years. Further research is necessary to examine whether our findings reflect sub-optimal management of early OA in terms of efficacy and equity.
Subject(s)
Delivery of Health Care/statistics & numerical data , Osteoarthritis, Hip/therapy , Osteoarthritis, Knee/therapy , Aged , Analgesics/administration & dosage , Complementary Therapies/statistics & numerical data , Dietary Supplements/statistics & numerical data , Drug Utilization/statistics & numerical data , Educational Status , Family Practice/statistics & numerical data , Female , Follow-Up Studies , Humans , Male , Middle Aged , Netherlands/epidemiology , Osteoarthritis, Hip/epidemiology , Osteoarthritis, Knee/epidemiology , Prevalence , Professional-Patient RelationsABSTRACT
OBJECTIVE: The aim of this study was to investigate early radiological and clinical outcome of autologous minced cartilage treatment as a single-step treatment option in patients with a chondral or osteochondral lesion (OCL) in the knee. DESIGN: Eighteen patients with an OCL in the knee were included. Cartilage from healthy-appearing loose bodies and/or the periphery of the defect were minced into small chips and sealed in the defect using fibrin glue. Preoperatively, and at 3 (n = 14) and 12 (n = 18) months follow-up, magnetic resonance imaging (MRI) was performed. The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) 2.0 score was used to assess the cartilage repair tissue on MRI at 12 months. The International Knee Documentation Score, Knee Injury and Osteoarthritis Outcome Score, EuroQoL-5D, and Visual Analogue Scale pain were collected preoperatively and 12 months after surgery. RESULTS: Three months postoperative, MRI showed complete defect filling in 11 out of 14 patients. Mean MOCART 2.0 score at 12 months was 65.0 ± 18.9 with higher scores for lateral femoral chondral lesions compared to medial femoral chondral lesions (75.8 ± 14.3, 52.5 ± 15.8 respectively, P = 0.02). Clinical and statistical significant improvements were observed in the patient-reported outcome measures at 12 months postoperatively compared to preoperatively. CONCLUSION: Treatment of OCLs using the autologous minced cartilage procedure resulted in good cartilage repair measured by MOCART 2.0. Clinically relevant improvements were observed in the clinical scores. This study suggests autologous minced cartilage as a promising, single-step treatment for OCLs.
Subject(s)
Cartilage, Articular , Humans , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/surgery , Cartilage, Articular/injuries , Fibrin Tissue Adhesive/therapeutic use , Transplantation, Autologous , Follow-Up Studies , Magnetic Resonance Imaging/methodsABSTRACT
Skeletogenesis and bone fracture healing involve endochondral ossification, a process during which cartilaginous primordia are gradually replaced by bone tissue. In line with a role for cyclooxygenase-2 (COX-2) in the endochondral ossification process, non-steroidal anti-inflammatory drugs (NSAIDs) were reported to negatively affect bone fracture healing due to impaired osteogenesis. However, a role for COX-2 activity in the chondrogenic phase of endochondral ossification has not been addressed before. We show that COX-2 activity fulfils an important regulatory function in chondrocyte hypertrophic differentiation. Our data reveal essential cross-talk between COX-2 and bone morphogenic protein-2 (BMP-2) during chondrocyte hypertrophic differentiation. BMP-2 mediated chondrocyte hypertrophy is associated with increased COX-2 expression and pharmacological inhibition of COX-2 activity by NSAIDs (e.g., Celecoxib) decreases hypertrophic differentiation in various chondrogenic models in vitro and in vivo, while leaving early chondrogenic development unaltered. Our findings demonstrate that COX-2 activity is a novel factor partaking in chondrocyte hypertrophy in the context of endochondral ossification and these observations provide a novel etiological perspective on the adverse effects of NSAIDs on bone fracture healing and have important implications for the use of NSAIDs during endochondral skeletal development.
Subject(s)
Cell Differentiation , Cell Enlargement , Chondrocytes/drug effects , Cyclooxygenase 2 Inhibitors/pharmacology , Cyclooxygenase 2/metabolism , Osteogenesis/drug effects , Pyrazoles/pharmacology , Sulfonamides/pharmacology , Alkaline Phosphatase/genetics , Alkaline Phosphatase/metabolism , Animals , Antigens, Differentiation/genetics , Antigens, Differentiation/metabolism , Bone Morphogenetic Protein 2/pharmacology , Bone Morphogenetic Protein 2/physiology , Celecoxib , Cell Line , Cell Proliferation , Chondrocytes/cytology , Chondrocytes/enzymology , Collagen Type II/genetics , Collagen Type II/metabolism , Collagen Type X/genetics , Collagen Type X/metabolism , Core Binding Factor Alpha 1 Subunit/genetics , Core Binding Factor Alpha 1 Subunit/metabolism , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/genetics , Gene Expression , Growth Plate/cytology , Growth Plate/drug effects , Membrane Proteins/metabolism , Mice , RabbitsABSTRACT
INTRODUCTION AND IMPORTANCE: Surgical treatment for dislocated trochlear shear injuries is recommended due to its articular nature. However, the surgical exposure is often limited and large cartilaginous fragments with lack of subchondral bone stock makes a stable fixation technically challenging. Rapid swelling of the traumatized cartilage induces a size misfit between the cartilage of the fragment and the defect site. The use of a "modified hedgehog"-based technique might be a solution in these cases. However, this technique has only been described in chondral shear lesions of the knee. CASE PRESENTATION: A fifteen-year-old boy fell out of the still rings during gymnastics at school and suffered trauma to his elbow. A CT-scan of the right elbow showed a coronal shear injury of the trochlea with accompanied lateral condyle fracture of the humerus. The patient was treated throughout an anterior neurovascular approach with a modified hedgehog-based technique with triple fixation by creating an interlocking match of the cartilage, application of fibrin glue and additional screw fixation. CLINICAL DISCUSSION: The anterior neurovascular interval approach provides a clear exposure of the fracture site which is useful for anatomic reduction and triple fixation. The subsequent modified hedgehog-based technique has only been described once in children with shear-off chondral fragments of the knee, without additional screw fixation. Adding a screw fixation of the fragment creates some collateral damage to the cartilage and might not be necessary in future cases. CONCLUSION: The anterior neurovascular approach seems elegant and provides adequate exposure. Furthermore, a modified hedgehog-based technique delivers a stable triple fixation of the osteochondral fragment.