| Autor: |
Laasanen, Mikko S., Töyräs, Juha, Vasara, Anna I., Hyttinen, Mika M., Saarakkala, Simo, Hirvonen, Jani, Jurvelin, Jukka S., Kiviranta, Ilkka |
| Předmět: |
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| Zdroj: |
Journal of Bone & Joint Surgery, American Volume; Apr2003 Supplement, Vol. 85, p78, 7p, 1 Diagram, 4 Graphs |
| Abstrakt: |
Background: The combined use of high-frequency ultrasound and mechanical indentation has been suggested for the evaluation of cartilage integrity. In this study, we investigated the usefulness of high-resolution B-mode ultrasound imaging and quantitative mechanical measurements for the diagnosis of cartilage degeneration and for monitoring tissue-healing after autologous chondrocyte transplantation. Methods: In the first study, osteochondral samples (n = 32) were obtained from the lateral facet of a bovine patella, and the samples were visually classified as intact (n = 13) or degenerated (n = 19) and were graded with use of the Mankin scoring system. Samples were imaged with use of a 20-MHz ultrasound instrument, and the dynamic modulus (E[subdyn]) of cartilage was determined in unconfined compression with use of a high-resolution materials tester. In the second study, cartilage chondrocytes were harvested from the low-weight-bearing area of six-month-old porcine knee joints and cultured. A month later, a cartilage lesion was created on the facet of the femoral trochlea and was repaired with use of the autologous chondrocyte transplantation technique (n = 10). Three months later, to estimate cartilage E[subdyn], the repair tissue, the adjacent cartilage, and the sham-operated contralateral joint cartilage (control) were analyzed in situ with an arthroscopic indentation instrument. Subsequently, the same sites were imaged with ultrasound. Results: All visually degenerated bovine samples (mean Mankin score = 4) and five visually normal samples (Mankin score = 1) showed reduced E[subdyn] (<2.1 MPa) as compared with histologically normal cartilage (E[subdyn] = 13.8 ± 3.2 MPa, Mankin score = 0). Cartilage stiffness, as shown by the indenter force, was lower (0.6 ± 0.3 N, p < 0.05, Wilcoxon's signed-rank test) in the porcine tissue repaired with autologous chondrocyte transplantation than it was in the adjacent (1.6 ± 0.1 N) or the control... [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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