Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CARTILAGE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62Linked to original sources
PubMed2002

Expression of CD44 in human neoplastic and normal hyaline cartilage.

Although low-grade cartilage neoplasms typically consist of hyaline-like cartilage, most of them also contain some fibrocartilaginous regions. CD44, a cell surface receptor for hyaluronan, has been identified in cartilage. A family of alternatively spliced mRNA containing the variant 6 (v6) exon sequence of CD44 has been linked to several types of neoplasms. We hypothesized that expressions of v6-containing CD44 species are associated with fibrocartilaginous regions of low-grade cartilage neoplasms. To test this hypothesis we performed reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemical analysis on eight samples: four from normal articular cartilage, one from a synovial chondromatosis, and three chondrosarcomas which were graded as I and I/II. The standard CD44s and a unique v6-containing CD44 species (CD44v6-10) were identified in all tissue samples by RT-PCR analysis. Immunohistochemically, using an antibody that cross-reacted with all CD44 species, CD44 was localized to the cell surface, lacuna wall and intracellular compartment of the chondrocytes in the middle and deep zone of normal cartilage, as well as with cells throughout the neoplastic masses. Utilizing an antibody specific for v6-containing CD44 species, the variant species was identified throughout cells of the middle and deep zone of normal cartilage, and localized selectively to intracellular positions. In neoplastic masses, v6-containing CD44 species were found associated only with cells in the hyaline-like cartilage, but not in the fibrocartilaginous regions. Thus a differential expression of the v6-containing CD44 species in the neoplastic masses containing both hyaline-like cartilage and fibrocartilaginous regions was observed when compared to its homogenous expression in normal hyaline cartilage. An involvement between the lack of the variant CD44 (v6-containing) and altered tissue phenotype (e.g., fibrocartilaginous) is suggested.

Bone Neoplasms↗
PubMed1975

[Stereological studies of aging changes in epiglottal cartilage cells].

The topic of these investigations were the aging changes of stereological parameters of the cells in human epiglottal cartilage. 42 sagittally cut epiglottides of all ages were available. By means of a drawing mirror in total 8937 cells had been drawn from the slide on paper and then measured. In detail we determined the volume fraction of cartilagous cells in the total cartilage volume, the complete cell surface area of the cartilage, the surface-to-volume ratio of the cartilagous cells, the numerical density of the cells and their volumes. The results are as follows: 1. The volume fraction of cartilagous cells in the total cartilage volume decreases from birth to senium continuously and, with the exception of a more rapid decline during the first decade, linear too. 2. The collective cell surface area per constant test volume of cartilage shows an exponential decline during life. 3. The surface-to-volume ratio of the cartilagous cells decreases very intensively during the first decades, from the 5th decade it little ranges again. 4. In the same way the numerical density of cells intensively decreases up to the 5th decade, but later on it ranges again. 5. The several volumes of cells show from the age of the newborn up to the 40th year a linear steep rise and afterwards, up to senium, an unequivocal decline. 6. The sizes of the cartilagous cells are not normally distributed, on the contrary, in young slides more than in older ones, one size class very predominates.

Adolescent↗
PubMed2002

[Improvement upon construction of tissue-engineered allogeneic cartilage molded with polyglycolic acid as the scaffold].

OBJECTIVE: To improve the method for constructing allogeneic molded cartilage by means of tissue engineering techniques. METHODS: The chondrocytes from the rib and articular cartilage of infant rabbits were harvested by type II collagenase digestion, followed by in vitro cell culture for 3 to 4 passages. The chondrocytes were then prepared into cell suspension and seeded onto C -and O -shaped pre-molded polyglycolic acid (PGA) scaffolds form chondrocyte-PGA composites, which were subsequently cultured in vitro for 7 to 10 d before implanted subcutaneously into adult rabbits. Improvement was made upon conventional shaping and implantation procedures. Morphological observation and cartilage regeneration assessment were conducted at different time points following the implantation, in comparison with the observation by conventional shaping and implantation methods. RESULTS: During in vitro cell culture, the rate of viable chondrocytes in the final cell suspension was (92+/-2)% after well-controlled prolongation of digestion trypsin, similar to the viable cell rate (93+/-2) % by traditional procedures (P>0.05). Gross observation found milk-white, newly generated cartilage which had good flexibility 4 weeks after implantation, and after 8 weeks and later, the cartilage took on the color of porcelain-white. Histological examination showed a few inflammatory cells around the newly generated immature cartilage 4 weeks after implantation, and the inflammation abated when the newly generated cartilage acquired similar histological properties to that of the original cartilage 8 weeks postoperatively and later. After 16 weeks, no blood vessel or capillaries were visible within the new cartilage. CONCLUSION: The chondrocyte viability is not affected when the cells are treated with well-controlled prolonged digestion with trypsin during in vitro cell culture. Improved PGA scaffolds shaping and the implantation procedure facilitate the regeneration of the cartilage after the implantation of the composites.

Animals↗
PubMedDate not supplied

Comparison between patella cartilage volume and radiological assessment of the patellofemoral joint.

OBJECTIVES: There is no information on how patella cartilage relates to the radiological grade of individual features of patellofemoral osteoarthritis (osteophytes or joint space narrowing) which have been used in most epidemiological and clinical studies. In this study we compared patella cartilage volume as measured by magnetic resonance imaging (MRI) with radiological assessment of the patellofemoral joint. METHODS: 157 subjects with specific features of patellofemoral osteoarthritis (osteophytes and joint space narrowing) ranging from grade 0-3 were examined (age 62 +/- 10 years, 62% female). Each subject had skyline and lateral patellofemoral radiographs performed. Patella cartilage volume was determined by processing images acquired in the sagittal plane using T1-weighted fat saturated MRI at an independent work station. RESULTS: Grade of joint space narrowing (JSN) as measured on skyline and lateral patellofemoral radiographs was inversely associated with patella cartilage volume. After adjusting for age, gender and body mass index, for every increase in grade of skyline JSN (0-3), the patella cartilage volume was reduced by 411 mm3. For every increase in lateral patellofemoral JSN grade (0-3), the adjusted patella cartilage volume was reduced by 125 mm3. The relationship was stronger for patella cartilage volume and skyline JSN (r = -0.54, p < 0.001) than for lateral patellofemoral JSN (r = -0.16, p = 0.015). There was no significant association between patella cartilage volume and osteophytes measured on skyline or lateral radiographs. CONCLUSIONS: There is a significant negative association between patella cartilage volume and JSN, but not osteophytes. This association was strongest for the skyline rather than lateral radiographs. Longitudinal studies will be needed to determine the role of patella cartilage measurement in assessing progression of patellofemoral osteoarthritis.

Age Factors↗
PubMed2003

[The experimental study of tissue engineered autologous cartilage using chitosan-gelatin complex scaffolds].

OBJECTIVE: To investigate whether man-made porous chitosan-gelatin complex scaffold was a appropriate scaffold for tissue engineering cartilage. METHODS: Chondrocytes isolated from Changfeng crossbred swines' auricular cartilage were seeded onto chitosan- gelatin scaffolds to be cultured in a three dimensional environment. The chondrocyte- polymer constructs were implanted into the subcutaneous tissue of the swines' abdomenal wall. Specimens were harvested and analyzed by gross observation, histology, type II collagen immunohistochemistry and biochemistry after 10 and 16 weeks in vivo respectively. RESULTS: H.E staining showed cartilage was formed, and chondrocytes were enclosed in lacuna with histological characteristics similar to natural cartilage. Some clusters of neocartilage surrounded by fibrous tissues were observed. Elastic fibres were observed in the mesenchyma of cartilage 16 weeks after by Vehoeff's staining. Immunohistochemical staining of the neocartilage with anti- type II collagen showed the presence of type II collagen in the ECM of tissue engineered cartilage. The proteoglycans content in tissue engineered cartilage was close to that of natural swine's auricular cartilage. CONCLUSION: The experiments demonstrated that using chitosan-gelatin complex scaffold we can generate autologous cartilage on animals with normal immune system. Porous chitosan- gelatin complex scaffolds may be a suitable scaffolds for tissue engineered cartilage.

Animals↗
PubMed2004

[Influence of different mechanical environments on repair of cartilage defect with rabbit marrow mesenchymal stem cells].

OBJECTIVE: To study the influence of different mechanical environments on repair cartilage defect with marrow mesenchymal stem cells as seed cells. METHODS: The rabbit marrow mesenchymal stem cells were isolated and cultured. The cartilage defects were repaired by autologous tissue engineered cartilage with the marrow mesenchymal stem cells as seed cells. Fifteen rabbits with cartilage defect were divided into 3 groups: dislocation group with cell-free scaffold (control group), dislocation group with cartilaginous construct and normal mechanical environment group with cartilaginous construct. The repaired tissue was harvested and examined 6 weeks postoperatively. RESULTS: The repair tissue in normal mechanical environment group with cartilaginous construct showed cartilage-like tissue in superficial layer and subchondral bone tissue in deep layer 6 weeks postoperatively. The defect was filled with bone tissue in dislocation group with cartilaginous construct 6 weeks postoperatively. The surrounding normal cartilage tissue showed vascular invasion from subchondral area and the concomitant thinning of the normal cartilage layer. The cartilaginous construct left in the femoral trochlea groove formed hyaline cartilage-like tissue. The defect was repaired by fibrous tissue in control group. CONCLUSION: The repaired tissue by tissue engineered cartilage with marrow mesenchymal stem cells as seed cells showed the best result in normal mechanical environment group, which indicates that it will be essential for the formation and maintenance of tissue engineered cartilage to keep the normal mechanical stress stimulus.

Animals↗
PubMed2004

Nucleus pulposus repair with cultured autologous elastic cartilage derived chondrocytes.

Low back pain is one of the most common medical conditions in the Western world. Disc degeneration, an inevitable process of ageing, is one of the major causes of low back pain. Autologous chondrocyte transplantation (ACT) is an increasingly popular method of addressing pathological disorders of cartilage. The purpose of our study was to determine whether autologous chondrocytes from elastic cartilage could survive and synthesise a cartilage specific matrix in the intervertebral disc of rabbits. Sixteen lumbar intervertebral discs (IVD) of New Zealand White rabbits were analysed. In 6 IVD, the nucleus pulposus was evacuated and replaced with tissue engineered autologous chondrocytes from auricular cartilage. In the second group, only the nucleus pulposus was evacuated from 6 IVD, with no chondrocytes implantation. Four non-operated IVD were used as a control. Six months after the operation, the animals were euthanized and the IVD were analysed histologically. Autologous cartilage implants were well tolerated by the host for up to six months in vivo. There was only hyaline-like cartilage in the place of the nucleus pulposus. We could not detect any elastic fibres in the new cartilage matrix. In IVD from which only the nucleus pulposus was evacuated and no chondrocytes were implanted, just fibrous tissue was found instead of nucleus pulposus. The overall histological analysis of new cartilage produced after implantation in our study confirmed the hypothesis that ACT from auricular cartilage can be implanted into the IVD instead of the nucleus pulposus and that a significant percentage of implanted chondrocytes survive and produce hyaline-like cartilage.

Animals↗
PubMed2004

[Digital speckle correlation method: a technique to evaluate the tensile property of articular cartilage].

OBJECTIVE: To establish a new technique for evaluation of the tensile property of articular cartilage using digital speckle correlation method (DSCM). METHODS: Three specimens of whole layer articular cartilage of the size of 10 mm x 4 mm were prepared from the cartilage of head of femur replaced from a 52-year-old male suffering from fracture of neck of femur (old control), the amputated tibia plateau of a 16-year-old female suffering from osteosarcoma (young control), and the cartilage of head of femur of a 19-year-old female suffering from spondyloepiphyseal dysplasia tarda with progressive arthropathy (SEDT-PA) and then underwent DSCM in U and V fields. RESULTS: The specimens of the 2 controls showed a smooth surface of cartilage and homologous deformation while the specimen of the SEDT-PA patient showed a rough surface of cartilage and deformation with increased undulation. Under a changed loading of 3.3 N the values of average strain of cartilage were 3800, 8800, and 9500 micro epsilon, and the values of tensile elastic modularity were 227.23, 89.59, and 127.25 MPa respectively for the old control, young control, and SEDT-PA patient. The numbers of pixel in U field after 20 pixels were moved in the X direction were significantly different between the old control subject and the SEDT-PA patient (0.101 +/- 0.022 vs 0.220 +/- 0.053, P = 0.023). The numbers of pixel in V field after 20 pixels were moved in the Y direction were significantly different among the old control subject and the SEDT-PA patient. Differences were also significant among the three kinds of cartilage (0.055 +/- 0.018, 0.196 +/- 0.057 vs 0.658 +/- 0.144, both P < 0.05). CONCLUSION: DSCM is a reliable technique to measure the tensile property of articular cartilage, especially for evaluation of small specimens. SEDT-PA is characterized by a dramatic decrease of tensile property, causing destruction and loss of the articular cartilage.

Adult↗
PubMed2004

[Possibility of using cartilage cultured in centrifuge tube as a substitute for meniscus].

OBJECTIVE: To compare biological characteristics between articular chondrocyte and meniscal fibrochondrocyte cultured in vitro and to investigate the possibility of using cultured cartilage as a substitute for meniscus. METHODS: Chondrocytes isolated from articular cartilage and meniscus of rabbits aged 3 weeks were respectively passaged in monolayer and cultured in centrifuge tube. Cartilages cultured in centrifuge tube and meniscus of rabbit aged 6 weeks were detected by histological examination and transmission electron microscopy. Growth curves of articular chondrocytes and meniscal fibrochondrocytes were compared; meanwhile, cell cycles of articular chondrocytes and meniscal fibrochondrocytes in passage 2 and 4 were separately measured by flow cytometry. RESULTS: Articular chondrocytes in passage 4 were dedifferentiated. Articular chondrocytes formed cartilage 2 weeks after cultivation in centrifuge tube, but meniscal fibrochondrocytes could not generate cartilage. The differences in ultrastructure and histology obviously existed between cultured cartilage and meniscus; moreover, apoptosis of chondrocytes appeared in cultured cartilage. Proportion of subdiploid cells in articular chondrocytes passage 2 and 4 was markedly higher than that in passage 2 and 4 fibrochondrocytes (P < 0.05). CONCLUSION: Meniscal fibrochondrocytes can not form cartilage after cultivation in centrifuge tube, while cartilage cultured in centrifuge tube from articular chondrocytes can not be used as graft material for meniscus. Articular cartilage is markedly different from meniscus.

Animals↗
PubMed2004

Slice thickness in the assessment of medial and lateral tibial cartilage volume and accuracy for the measurement of change in a longitudinal study.

OBJECTIVE: The optimal magnetic resonance image (MRI) slice thickness required to assess cartilage volume accurately and efficiently in cross-sectional and longitudinal studies is unknown. We compared cartilage volume measured from MRI of the knees using different slice thicknesses (1.5 to 7.5 mm) and assessed longitudinal change. METHODS: A total of 123 subjects with osteoarthritis had baseline and followup MRI on their symptomatic knee at 2 years. Medial and lateral tibial cartilage volumes were calculated using increasing slice thickness by extracting each second, third, fourth, or fifth slice area to calculate total volume, which was compared to the "gold standard" volume calculated from the original 1.5 mm slices. RESULTS: There was little difference in the average medial and lateral tibial cartilage volume observed as the slice thickness increased from 1.5 to 7.5 mm; medial tibial cartilage volume ranged from 1750 microl to 1787 microl and lateral tibial cartilage volume ranged from 1949 microl to 2007 microl. There was also little absolute difference in the average change in medial and lateral tibial cartilage volume measured over 2 years. However, with increasing slice thickness, there was a decreased correlation between the tibial cartilage volume change calculated from the increased slice thickness, with the lowest correlation being 0.77 (p < 0.001) when the lateral cartilage volume calculated from the 7.5 mm slice was compared to the 1.5 mm slices. CONCLUSION: Increasing slice thickness may provide sufficiently accurate measurement of tibial cartilage volume and change over time in some studies. This would result in reduction in MRI scanning and postimaging processing time, which has the potential of increasing the feasibility of this technique.

Aged↗
PubMed2004

[Treatment of patellar cartilage defects by solid chondral graft: first experience].

PURPOSE OF THE STUDY: To present the results of a new method for treatment of cartilage defects of the patella, using a solid graft produced by chondrocytes on a three-dimensional matrix. MATERIAL AND METHODS: Chondrocyte transplantation is indicated in deep and extensive chondral and osteochondral defects of all large joints in patients at 18 to 40 years of age. When, on arthroscopic examination, a defect of patellar cartilage was found, healthy cartilage was collected from a non-weight-bearing surface, i. e., the intercondyllar fossa. In the tissue bank, the cartilage was fragmented, chondrocytes were isolated enzymatically and cultivated in vitro under a permanent assessment for cell quality. The cultivation period ranged from 15 to 35 days. Subsequently, a solid graft was prepared with the use of Tissucol glue, a three-dimensional matrix. The graft was transplanted after arthroscopic verification of the defect by an open, minimally invasive procedure with tourniquet application, with the patient receiving antibiotics. The result of chondral graft implantation was checked by second-look arthroscopy involving removal of a small sample of the integrated chondral graft taken for histological and morphological examination. Another method of post-operative assessment was examination by magnetic resonance imaging (MRI). Solid chondral graft transplantation was used in three patients (two men and one women) treated in the Department of Orthopedics, University Hospital Brno, between May 2001 and December 2003. Their average age at the time of surgery was 31 years (range, 27 to 38 years). The average follow-up was 22 months (range, 2 to 33 months). The post-operative stage of he cartilage was assessed by MRI in one patient and by second-look arthroscopy also in one patient. RESULTS: Two patients fully resumed their daily activities, sports including, at 6 months after the treatment, with one reporting mild chondropathic problems and the other being without complaints. In the third patient at 2 months after surgery, the treatment had not been completed yet. The patella examined by MRI at 18 months after surgery showed a confluent, high layer of hyaline cartilage covering the articular surface. Second-look arthroscopy and histological examination also revealed healthy hyaline cartilage. No serious complications were recorded. DISCUSSION: Autologous chondrocyte transplantation is indicated in younger, active patients with cartilage defects exceeding 2 cm2 and in patients undergoing revision surgery for any defect. The success rate of this procedure has been reported to be over 90 %. One year after transplantation, the cartilage had characteristics of a healthy tissue, as assessed by MRI. Biopsy examination showed that the grafts, chondrocytes as well as osteocytes maintained their integrity at 2 to 12 months after surgery. CONCLUSIONS: The aim of this paper was to define and check indications, to develop the surgical technique, to improve post-operative management and to evaluate mid-term results of the treatment of cartilage defects on the patella.

Adolescent↗
PubMed2005

Histological and histochemical investigations of nasal septum cartilage in nasal deformations.

AIM of the study is to identify histological and histochemical peculiarities of nasal septum cartilage reconstruction in patient with different remoteness of trauma. MATERIALS AND METHODS: Patients of both sexes at the age of 16-39 years have been operated on. Depending on remoteness of the period from the trauma, witch caused the deformation, till the surgery, the materials was divided into 2 group: I group (36 patients) 1-5 years from the trauma to the surgery, II group (23 patient) 10-20 years from the trauma to the surgery. Bioptats of the nasal septum cartilage were fixed in Carnoy mixture. Paraffin sections were stained with hematoxilin and eozin, after Van Ghison on collagen fibrils, toluidine blue on acid glycoaminglicans (GAG) and Brashe reaction on RNA. STUDY RESULTS AND CONCLUSION: Thus, the histological and histochemical investigation of nasal septum cartilage, received in rhinoplasty, has revealed dystrophic changes in cartilage. Basing on the analysis of the material, we can conclude that the degree of expression of these changes depends on three factors: - localization of examined area of the nasal septum (bioptat); - the period of time the deformation exist; - the degree of septum curvature. The structure of cartilage bioptates in the patients with relatively short (1-5 years) duration of traumatic deformation differs from the normal hyaline cartilage by moderate dystrophic changes of some chondrocytes (20-25% of all the cells) in the central zone of the cartilage as well as by irregular distribution of acid GAG in cartilage matrix. Cartilage tissue dystrophic changes are still more pronounced in the patients with a longer period of nose deformation including nasal septum curvature. This fact indicates that these changes are connected with deformation duration rather than with etiology of the process. The analysis of material also enable to find the dependence of cartilage dystrophic changes on the degree of nasal septum deformation: at the 3rd degree of curvature, chondropathy is more pronounced than at the 1st-2nd degree.

Adolescent↗
PubMedDate not supplied

Acoustic properties of articular cartilage under mechanical stress.

Mechano-acoustic and elastographic techniques may provide quantitative means for the in vivo diagnostics of articular cartilage. These techniques assume that sound speed does not change during tissue loading. As articular cartilage shows volumetric changes during compression, acoustic properties of cartilage may change affecting the validity of mechano-acoustic measurements. In this study, we examined the ultrasound propagation through human, bovine and porcine articular cartilage during stress-relaxation in unconfined compression. The time of flight (TOF) technique with known cartilage thickness (true sound speed) as well as in situ calibration method [Suh, Youn, Fu, J. Biomech. 34 (2001), 1347-1353] were used for the determination of sound speed. Ultrasound speed and attenuation decreased in articular cartilage during ramp compression, but returned towards the level of original values during relaxation. Variations in ultrasound speed induced an error in strain and compressive moduli provided that constant ultrasound speed and time-of-flight data was used to determine the tissue thickness. Highest errors in strain (-11.8 +/- 12.0%) and dynamic modulus (15.4 +/- 17.9%) were recorded in bovine cartilage. TOF and in situ calibration methods yielded different results for changes in sound speed during compression. We speculate that the variations in acoustic properties in loaded cartilage are related to rearrangement of the interstitial matrix, especially to that of collagen fibers. In human cartilage the changes, are, however relatively small and, according to the numerical simulations, mechano-acoustic techniques that assume constant acoustic properties for the cartilage will not be significantly impaired by this phenomenon.

Adult↗
PubMedDate not supplied

Effects of joint unloading and reloading on human cartilage morphology and function, muscle cross-sectional areas, and bone density - a quantitative case report.

Recent studies have shown that thinning of human cartilage occurs with unloading, but no data are available on the effect of remobilization (after immobilization) on knee joint cartilage status in humans. We examined a 36-year-old patient after 6 weeks of unilateral immobilization. Knee joint cartilage morphology (patella and tibia), patellar cartilage deformation, and thigh muscle cross-sectional areas were assessed with quantitative MR imaging and bone density with peripheral quantitative computed tomography (pQCT) during 24 months of remobilization. The immobilized limb displayed lower muscle cross-sectional areas (MCSA) of the knee extensors (-36%), lower bone density of the femur and tibia (-12/-6%), lower patellar cartilage thickness (-14%), but no side differences of tibial cartilage thickness. During remobilization, side differences decreased to -4% for knee extensor MCSAs, to -6%/-3% for femoral and tibial BMD, and to -8% for patellar cartilage thickness. No change was observed in tibial cartilage. Patellar deformation decreased from 9% to 4% after 15 months. In conclusion, we observed substantial changes of thigh MCSAs, but little (patella) to no (tibia) change in cartilage thickness during remobilization. These preliminary results indicate that human cartilage macro-morphology may be less adaptive to variations of the mechanical loading than muscle and bone.

Adult↗
PubMed1991

Biochemical changes in knee joint articular cartilage after cemented prosthetic hip hemiarthroplasty in dogs.

Biochemical changes in the distal femoral articular cartilage (knee joint) after cemented prosthetic replacement of the femoral head were determined. Femurs from dogs (n = 10) that had undergone cobalt-chromium prosthetic hip hemiarthroplasty (6-8 months postoperatively) were analyzed for articular cartilage lipids in the distal femur. The quantity of phosphatidylserine increased from 0.59 +/- 0.14 mg (uninvolved) to 1.52 +/- 0.23 mg (hemiarthroplasty) lipid phosphorus/100 g tissue, and the quantity of arachidonic acid in the articular cartilage increased from 0.23 +/- 0.07 mg (uninvolved) to 2.07 +/- 0.29 mg/100 g tissue (hemiarthroplasty). Likewise, hydroxyproline content was higher in the recipient femurs (77.4 +/- 1.58 micrograms/mg cartilage) versus uninvolved femurs (71.8 +/- 1.03 micrograms/mg cartilage); the activity of acid phosphatase was greater in the recipient distal femoral cartilage as compared with the uninvolved femur, 0.07 +/- 0.01 and 0.06 +/- 0.02 mol hydrolyzed per kilogram per hour, respectively, and the hexosamine content was lower in the recipient femur knee cartilage versus knee cartilage from uninvolved femurs, 54.5 +/- 1.51 and 63.1 +/- 1.37 micrograms/mg cartilage, respectively. These biochemical changes may suggest degeneration of the knee joint articular cartilage after cemented hip hemiarthroplasty.

Acid Phosphatase↗
PubMed1979

[Physiology and pathology of the epiphyseal cartilage (author's transl)].

Knowledge of the physiology of the epiphyseal cartilage, respectively epiphyseal plate, is essential for an understanding of defective growth and abnormal modeling of the long bones. The epiphyseal cartilage develops from the embryonal, cartilaginous long bone structure. The histology of the epiphyseal cartilage is characterised by definable zones representing the individual differentiation steps from the reformation of cartilage to chondrolysis. Modeling of the ends of the long bones is also influenced by a transversal and longitudinal direction of growth in the epiphyseal cartilage. The intercellular substance mainly contains collagin, proteoglycanes and non-collagenic proteins. These macromolecules are compounded by means of physicochemical bonds and are responsible for the special mechanical qualities of the hyaline cartilage. The process of mineralisation at the base of the epiphyseal cartilage is an essential differentiating step for the ossification processes which take place in the metaphysis. Two pathogenetic principles at the epiphyseal cartilage appear to be important for the defective growth of the long bones. On the one hand, the flowing equilibrium between the differentiation steps of cartilage reformation, transformation of the hyaline cartilage into a mineralised cartilaginous tissue and chondrolysis is changed, whereas on the other hand the turnover of these differentiation steps is retarded or accelerated.

Animals↗
PubMed1979

[Morphologic indication for the participation of neutrophil granulocytes in rheumatic cartilage destruction].

Cartilage destruction in rheumatoid arthritis may be mediated by enzymes of the synovial fluid and by cells of the proliferating pannus tissue. Neutrophilic granulocytes are usually said to affect the cartilage via the synovial fluid, and their local occurrence in the pannus-cartilage border is denied. However, a morphological study on pannus tissue and cartilage by use of histochemistry and immunfluorescence (leucocytes antielastase) exhibited an accumulation of neutrophilic granulocytes in the immediate vicinity of the cartilage in destruction. This result is in contrast to the observation of most investigators reporting studies of the pannus cartilage junction. Experimental datas of the effect of elastase moreover indicate that this enzyme is capable to penetrate into the cartilage and to degrade proteoglycans. Therefore the results show that the occurrence of neutrophilic granulocytes at the pannus-cartilage border is an important phenomenon for understanding the progressive cartilage destruction and that elastase may be at least one enzyme responsible for the degradation of the cartilage matrix.

Cartilage Diseases↗
PubMed1978

Subchondral route for nutrition to articular cartilage in the rabbit. Measurement of diffusion with hydrogen gas in vivo.

The route of nutrients going to articular cartilage was studied by determining the diffusion of hydrogen molecules from the subchondral circulation to the articular cartilage in rabbits. In all immature animals there was diffusion of hydrogen from subchondral bone into articular cartilage, while in the older immature animals the results were variable. None of the mature animals showed any diffusion of hydrogen into articular cartilage. The rate of diffusion of hydrogen was significantly lower in the articular cartilage than in the subchondral bone in the immature animals while the concentrations of hydrogen in the articular cartilage were only fractions of those in the subchondral bone at the same instant. Histologically, the deep layers of immature cartilage are penetrated extensively by vascular buds from the ossified portion of the epiphysis, while in adults the articular cartilage is separated from subchondral vascular spaces by an end-plate of bone. Blood vessels penetrating into the basilar layer of articular cartilage in immature animals appear to play an important role in the nutrition of articular cartilage coming from the subchondral region.

Animals↗