Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The pathogenesis and clinical progress of chondromalacia patellae have not been well studied in experimental models. We, therefore, studied the patellar subluxation produced experimentally in rabbit knees. In this model, sequential changes of the patellar cartilage were followed by simple X-rays, CT, macroscopic, histologic and scanning electron microscopic examinations up to 32 weeks. Pathological changes extending from horizontal fissures in the middle to the deep layers of the patellar cartilage and thinning of the subchondral bone were found at about six weeks after operation. The early changes of chondromalacia patellae were mostly what is called the basal degeneration, which was presumably attributed to the shearing stress on the articular cartilage. The sequential changes were not very remarkable; none of the rabbits developed OA changes by thirty-two weeks after operation. From these findings, we have that the cartilaginous changes in chondromalacia patellae progress very slowly which probably result from the vigorous repair by the cartilage and also from the acquisition of adaptability on the patellofemoral joint.
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PMID:[An experimental study on early changes of articular cartilages in subluxated patella of rabbits]. 195 2

Magnetic resonance (MR) images of the posterior patellar hyaline articular cartilage were obtained in 23 subjects to determine if MR imaging could accurately demonstrate the patellar cartilage. Arthroscopy was used as the standard of reference. Three subjects were asymptomatic volunteers. In the remaining 20 who had patellofemoral pain, arthroscopy was performed before MR imaging in seven and afterward in 12; one did not undergo arthroscopy. MR imaging showed focal areas of swelling of the patellar cartilage, focal hypointensity, surface irregularity, areas of thinning, and areas of cartilage loss with exposure of subchondral bone. The surgical findings agreed with those from MR images in all seven patients who underwent arthroscopy before MR imaging and in ten of the 12 who underwent surgery afterward. MR imaging is an accurate means of examining the posterior patellar cartilage and should be considered as an alternative to diagnostic arthroscopy when chondromalacia patellae is suspected.
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PMID:Chondromalacia patellae: assessment with MR imaging. 361 77

There are many theories concerning the etiology of chondromalacia patellae, as well as many points which have not been fully investigated yet. Using rabbits experimentally, shortening and elongation of the 3 mm patellar ligament were performed, producing the changes of contact surface and pressure on the patellar cartilage, and the patellar cartilage and the subchondral bone were studied sequentially. In the group of shortening, after the course of 16 weeks, no particular changes were recognized in the cartilage and the subchondral bone, compared with the control. In the group with elongation, 2-4 weeks after the operation, thinning of the trabecular and the subchondral bone, proliferation of blood vessels in the subchondral bone and their invasion into the calcified cartilage, were seen, without abnormality in the articular cartilage. After 4 weeks, irregularity or disappearance of the tide mark and degeneration of the ground substance toward the deep layer of the cartilage began to be recognized. After 8 weeks fasciculation was produced in the ground substance from the deep to the middle layers of the cartilage. After 12 weeks, degeneration extended to the superficial layer of the cartilage, producing blister formation, fibrillation and fissura, and finally proceeding to the desquamation of the superficial layer, degeneration and decrease in the thickness of the cartilage. These findings are similar to the histological findings of chondromalacia patellae, and seem to be different from those of arthrosis deformans in the bony changes. It is further suggested that decrease of contact surface and pressure on the cartilage can be considered to be one of the causes for chondromalacia patellae.
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PMID:[Experimental study of chondromalacia patellae (author's transl)]. 733 51

Chondromalacia can cause joint pain and synovial effusion with the potential for developing into osteoarthritis. Thermal chondroplasty using radiofrequency energy (RFE) has been reported to be superior to mechanical debridement for treating chondromalacia. We compared short-term changes in biomechanical properties of articular cartilage after treatment with monopolar (mRFE) or bipolar RFE (bRFE) or mechanical debridement (MD) on experimentally created grade II chondromalacia patellae. Chondromalacia patellae was created arthroscopically in both patellae of 15 ponies. Ten months after surgery, each patella was randomly assigned to one of four experimental groups: sham operated, untreated control; MD; bRFE; and mRFE. Animals were euthanized 6 months after treatment and fresh osteochondral sections were collected from the treated area, the border of the chondromalacic and nonchondromalacic area, and from two untreated areas for analysis of mechanical properties. The same areas were harvested from an additional six untreated ponies. The aggregate modulus (H(A)), Poisson's ratio (nu(s)), and permeability (k) were determined for each area under creep indentation, and cartilage thickness was measured with a needle probe. The relation between zone of calcified cartilage (ZCC) and mechanical properties of hyaline cartilage (HC) was assessed histomorphometrically. Treated areas of all four groups had inferior mechanical properties compared at the same location. The treated and border areas had significantly lower H(A) values than the untreated areas. Permeability values showed significant differences between bRFE and other treated groups. Chondromalacic areas showed thinning of cartilage compared to nonchondromalacic areas. Biomechanical properties of the injured cartilage were inferior to nonchondromalacic cartilage regardless of the treatment type. mRFE had the highest stiffness value compared to other treatments and significantly higher values than MD. A significant correlation was observed between the mechanical properties of HC and ZCC thickness.
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PMID:In vivo study on the short-term effect of radiofrequency energy on chondromalacic patellar cartilage and its correlation with calcified cartilage pathology in an equine model. 1651 62