| 1. |
- Saarakkala, Simo, et al.
(författare)
-
Ultrasound indentation of normal and spontaneously degenerated bovine articular cartilage.
- 2003
-
Ingår i: Osteoarthritis and Cartilage. - : Saunders Elsevier. - 1063-4584 .- 1522-9653. ; 11:9, s. 697-705
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: We have previously developed a handheld ultrasound indentation instrument for the diagnosis of cartilage degeneration. The instrument has been demonstrated to be capable of quantifying mechanical and acoustic properties of enzymatically degraded and normal bovine articular cartilage in vitro and in situ. The aim of this study was to investigate the sensitivity of the instrument to distinguish between normal and spontaneously degenerated (e.g., in osteoarthrosis) articular cartilage in vitro.DESIGN: Thirty articular cartilage samples were prepared from the bovine lateral patellae: 19 patellae with different degenerative stages and 11 patellae with visually normal appearance. Cartilage thickness, stiffness (dynamic modulus) and ultrasound reflection from the cartilage surface were measured with the handheld instrument. Subsequently, biomechanical, histological and biochemical reference measurements were conducted.RESULTS: Reproducibility of the measurements with the ultrasound indentation instrument was good. Standardized coefficient of variation was < or =6.1% for thickness, dynamic modulus and reflection coefficient. Linear correlation between the dynamic modulus, measured with the ultrasound indentation instrument, and the reference dynamic modulus was high (r=0.993, n=30, P<0.05). Ultrasound reflection coefficient, as determined from the cartilage surface, showed high linear correlations (typically r(2)>0.64, n=30, P<0.05) with the cartilage composition and histological or mechanical properties. The instrument was superior compared to visual evaluation in detecting tissue degeneration.CONCLUSION: This study indicates that the ultrasound indentation technique and instrument may significantly improve the early diagnosis of cartilage degeneration. The results revealed that visual evaluation is insensitive for estimating the structural and mechanical properties of articular cartilage at the initial stages of degeneration.
|
|
| 2. |
- Fahlgren, Anna, 1972-, et al.
(författare)
-
TGF-β1 as a prognostic factor in the process of early osteoarthrosis in the rabbit knee
- 2001
-
Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584 .- 1522-9653. ; 9:3, s. 195-202
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To assess changes in knee joint fluid concentrations of transforming growth factor-β1 (TGF-β1) and proteoglycan (PG) fragments during the early course of post-traumatic osteoarthrosis (OA) after meniscectomy in the rabbit knee, and to ascertain whether the concentrations of these substances shortly after operation could be used as prognostic markers for the OA process.Design In 15 rabbits with medial meniscectomy in one knee and a sham operation in the other knee, synovial lavage fluid samples were taken repeatedly, before operation, every third week post-operatively until 12 weeks, thereafter every sixth week, and at death. Five rabbits each were killed at 13, 25 and 40 weeks. Synovial lavage fluid samples from five non-operated rabbits served as controls. At death, two histological scores were formed that characterized the highest (MAX) and the overall (ALL) degree of OA changes in each joint.Results TGF-β1 and PG fragment concentrations in synovial lavage fluid correlated highly (R=0.81, P< 0.001). Both OA scores were higher in meniscectomized than controls (P< 0.05). The synovial lavage fluid concentration of TGF-β1 at 3 weeks, but no other time point, correlated to the histological scores (ALL, R=0.58; MAX, R=0.52;P< 0.001).Conclusion Higher concentrations of TGF-β1 in synovial lavage fluid early after surgery seemed indicative for the later development of more severe OA changes in contrast to lower concentrations. The association between TGF-β1 and the changes found later in the cartilage was underlined by the high correlations between this substance and PG fragment concentrations in synovial lavage fluid at all time points.
|
|
| 3. |
- Hyttinen, Mika, et al.
(författare)
-
Age matters : collagen birefringence of superficial articular cartilage is increased in young guinea-pigs but decreased in older animals after identical physiological type of joint loading.
- 2001
-
Ingår i: Osteoarthritis and Cartilage. - : Saunders Elsevier. - 1063-4584 .- 1522-9653. ; 9:8, s. 694-701
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To compare responses of the collagen network and glycosaminoglycans (GAGs) of articular cartilage to physiological type of joint loading in young growing and adult mature guinea-pigs.DESIGN: 10- and 44-week-old guinea-pigs were accustomed to treadmill running for 3 weeks. Thereafter the animals ran 2500 m/day, 5 days a week, for 15 weeks. Articular cartilage specimens from knee joints were collected at 28 and 62 weeks. Osteoarthritis (OA) prevalence and severity was evaluated by aid of light microscopy. The degree of collagen fibril network organization and content was analyzed with quantitative polarized light microscopy. The local concentration of GAGs was determined from cartilage sections with digital densitometry after safranin-O staining.RESULTS: In the young guinea-pigs, running increased up to 24% the optical retardation of polarized light by collagen in the superficial articular cartilage of femur, indicating either a higher degree of fibril assembly and organization or increased amount of collagen, or both. In contrast, in the adult mature animals the optical retardation decreased almost 50% after joint loading (P< 0.01-0.001). Running did not increase cartilage fibrillation. Significant changes in GAG content of cartilage were not found either in the young or adult mature runners.CONCLUSIONS: Increased birefringence of the superficial articular cartilage after joint loading in young guinea-pigs can be interpreted to be a sign of improved and decreased birefringence in older animals a sign of worsened property of the collagen network. It can be suggested therefore that joint loading strengthened the collagen network in the young runners. It can be hypothesized further that with time the inferior property of the collagen network predisposes the older runners to earlier OA than in controls.
|
|
| 4. |
- Kaarniranta, Kai, et al.
(författare)
-
Primary chondrocytes resist hydrostatic pressure-induced stress while primary synovial cells and fibroblasts show modified Hsp70 response.
- 2001
-
Ingår i: Osteoarthritis and Cartilage. - : Saunders Elsevier. - 1063-4584 .- 1522-9653. ; 9:1, s. 7-13
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: During joint loading, chondrocytes in the articular cartilage are subjected to gradients of high compressive hydrostatic pressure (HP). In response to diverse chemical or physical stresses, heat shock genes are induced to express heat shock proteins (Hsps). This study sought to examine the role of Hsps in baroresistance in primary bovine chondrocytes and synovial cells, as well as in primary human fibroblasts.METHODS: Northern blotting was used to analyze the steady-state levels of hsp70 mRNA in the primary cells exposed to HP or heat stress. Hsp70 protein accumulation was analyzed by Western blotting, and the DNA-binding activity was examined by gel mobility shift assay.RESULTS: Primary bovine chondrocytes which have been adapted to live under pressurized conditions showed negligible Hsp70 response upon HP loading, whereas primary bovine synovial cells and human fibroblasts accumulated hsp70 mRNA and protein when subjected to HP. The response was initiated without activation of the heat shock transcription factor 1. Interestingly, pre-conditioning of the barosensitive fibroblasts with HP or heat shock reduced the Hsp70 response, indicating induction of baroresistance.CONCLUSION: This study suggests that Hsp70 can play an important role in the early stages of adaptation of cells to HP. Thus, the Hsp70 gene expression upon HP loading may serve as one indicator of the chondrocytic phenotype of the cells. This can be of use in the treatment of cartilage lesions.
|
|
| 5. |
- Messner, Karola, 1956-, et al.
(författare)
-
Simultaneous changes in bone mineral density and articular cartilage in a rabbit meniscectomy model of knee osteoarthrosis
- 2000
-
Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584 .- 1522-9653. ; 8:3, s. 197-206
-
Tidskriftsartikel (refereegranskat)abstract
- Objective It was hypothesized that increased bone mineral density of the medial proximal tibia would precede or coincide with the development of more severe cartilage changes after meniscectomy.Methods In a rabbit knee model, mineral density of subchondral bone and changes of articular cartilage were monitored 13 to 40 weeks after medial meniscectomy or a sham operation.Results Both procedures resulted in a decrease of bone mineral density, especially of the medial proximal tibia, which persisted up to 40 weeks (P< 0.02–0.0007). Meniscectomy induced cartilage changes typical for osteoarthrosis (P< 0.009), which progressed over time on the posterior aspect of the medial tibial plateau (P< 0.009), which is physiologically covered by the meniscus, but the procedure also induced iatrogenic changes which were located mainly on the anterior aspect of the concerned compartment, and which did not progress or develop to osteoarthrosis.Conclusions The data suggest that the cartilage changes after meniscectomy in this animal model are caused by the surgical trauma, subsequent limb misuse, and altered load distribution, and initially associated by a decrease not an increase in bone mineral density of the proximal tibia. Moreover, the cartilage changes progressed without a simultaneous increase of the bone mineral density at corresponding sites.
|
|
| 6. |
- Roos, E.M., et al.
(författare)
-
Long-term outcome of meniscectomy : symptoms, function, and performance tests in patients with or without radiographic osteoarthritis compared to matched controls
- 2001
-
Ingår i: Osteoarthritis and Cartilage. - : Elsevier. - 1063-4584 .- 1522-9653. ; 9:4, s. 316-324
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To describe the long-term influence of meniscectomy on pain, functional limitations, and muscular performance. To assess the effects of radiographic osteoarthritis (OA), gender and age on these outcomes in patients with meniscectomy.DESIGN: 159 subjects (35 women), mean age 53 years, were examined 19 (17-22) years after open meniscectomy. Self-reported symptoms and function were assessed, performance tests were carried out and radiographs were taken. Sixty-eight age- and gender-matched controls were examined likewise. The data was analysed in two steps. First, subjects with meniscectomy were compared to the controls, and subgroup analyses were carried out with regard to radiographic OA, gender and age. Second, similar comparisons were carried out within the meniscectomized group.RESULTS: Meniscectomized subjects reported significantly (P< 0.001) more symptoms and functional limitations than did controls. This was also true when operated subjects without OA were compared to controls without OA. Within the meniscectomized group, severe radiographic OA (joint space narrowing grade 2 or more) and female gender, but not older age, was associated with more symptoms and functional limitations. Meniscectomy was associated with worse muscular performance. Female gender and older age were associated with worse muscular performance in the study group.CONCLUSIONS: Meniscectomy is associated with long-term symptoms and functional limitations, especially in women. Patients who had developed severe radiographic OA experienced more symptoms and functional limitations. Age did not influence self-reported outcomes, however older age was associated with worse muscular performance.
|
|
| 7. |
- Boegard, TL, et al.
(författare)
-
Distribution of MR-detected cartilage defects of the patellofemoral joint in chronic knee pain
- 2003
-
Ingår i: Osteoarthritis and Cartilage. - 1063-4584. ; 11:7, s. 494-498
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: The aim of the study was to detect cartilage defects and determine the center of these defects in MR imaging of the patellofemoral joint (PFJ) in middle-aged people with chronic knee pain. Design: In the format of a prospective study of early osteoarthritis (OA), this cross-sectional study of the signal knee (the most painful one at inclusion in the study in 1990) in 59 individuals, 30 women and 29 men (aged 41-58 years, mean 50 years) with chronic knee pain, with or without radiographically determined knee OA, was examined using MR imaging on a 1.0 T imager. Cartilage defects and the center of these defects in the PFJ were recorded. Results: Cartilage defects were found more often in the patella (40 knees) than in the femoral trochlea (23 knees) (P<0.001) and were unevenly distributed in the patella (P<0.001), with most cartilage defects in the mid-patella. Conclusions: Since cartilage defects occur more commonly in the mid-patella, radiographs obtained with a knee flexion of approximately 45 may be more accurate to show cartilage defects of early OA of the PFJ than views with another knee flexion. Crown Copyright (C) 2003 Published by Elsevier Science Ltd on behalf of OsteoArthritis Research Society International. All rights reserved.
|
|
| 8. |
- Boegard, TL, et al.
(författare)
-
Joint space width of the tibiofemoral and of the patellofemoral joint in chronic knee pain with or without radiographic osteoarthritis: a 2-year follow-up
- 2003
-
Ingår i: Osteoarthritis and Cartilage. - 1063-4584. ; 11:5, s. 370-376
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: To assess the interval change of the minimal joint space width (MJS) in radiographs of the tibiofemoral (TF) joint and of the patellofemoral (PF) joint with a 2-year follow-up in middle-aged people with longstanding knee pain with or without radiographic osteoarthritis (OA) and to study the precision of the MJS measurements. Design: In the format of a prospective study of early OA the signal knee in 55 people, 28 men and 27 women (aged 41-57 years, median 50), with chronic knee pain at inclusion was examined with a 2-year interval (median 25 months, range 21-30). The MJS of the TF joint was measured using a flexed PA view in weightbearing and the MJS of the PF joint using an axial view in standing. Results: The MJS of the TF joint decreased medially by 0.056+/-0.44 mm (n.s.) and increased laterally by 0.080+/-0.51 mm (n.s.) during the time of observation. In knees with an MJS medially that was less or the same as compared with the lateral compartment, the MJS decreased by 0.14+/-0.38 mm (p=0.038) and in a subgroup of these knees, without osteophytes, the MJS decreased by 0.14+/-0.27 mm (p=0.01 8). The MJS of the PF joint decreased by 0.019 mm (n.s.) during the time of observation. The coefficient of variation for intra- and interobserver MJS measurements of the TF joint was 1.0 and 1.1% medially and 2.3 and 2.7% laterally, and for measurement error 6.9% medially and 4.8% laterally, respectively. The coefficient of variation for intra- and interobserver MJS measurements of the PF joint was 8.1 and 5.8% medially and 7.5 and 10.1% laterally and for the measurement error it was 8.1% medially and 8.5% laterally, respectively. Conclusions: A statistically significant reduction of the. MJS was only demonstrated in the medial compartment of the TF joint in those individuals who had an MJS in this compartment which was less or the same as compared with the lateral compartment as well as in a subgroup of these knees without osteophytes. The radiographic examinations and the MJS measurements were reproducible. (C) 2003 OsteoArthritis Research Society International. Published by Elsevier Science Ltd. All rights reserved.
|
|
| 9. |
- Altman, RD, et al.
(författare)
-
Measurement of structural progression in osteoarthritis of the hip: the Barcelona consensus group
- 2004
-
Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 12:7, s. 515-524
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To outline the best available method of measurement for detecting progression of osteoarthritis (OA) of the hip especially in therapeutic trials. Method A Medline search of articles related to progression of hip CA was performed. A group of experts met over a 1.5-day session to review available literature and new research. Specific questions were addressed in order to reach a consensus on measuring progression of CA of the hip. Results: Of the available surrogate measures, a single yearly standing or reclined antero-posterior plain radiograph of the pelvis with feet internally rotated 15-20degrees, can be evaluated with the use of an atlas for joint space width (JSW, interbone distance). There should be a minimum JSW upon baseline screening that may be 1 or 2 mm. Digitization of films offers a slight reduction in variability of measurements. Progression of OA can be calculated by measurement of the JSW on paired and blinded films. A reduction of greater than or equal to0.5 mm is greater than the 'minimum perceptible difference' as well as the variation of most imaging techniques, and represents a clinically relevant and significant reduction in the JSW. Narrowing of the superomedial or superolateral JSW may tend to progress more rapidly than other changes. In clinical trials, patients who discontinue the study treatment need to be followed after discontinuation, and an imputation strategy which provides unbiased estimates of both the treatment effect and its variance is an appropriate technique for intent-to-treat analysis. Conclusion: For the development of new agents intended to prevent, retard, stabilize or reverse the progress of CA of the hip, the radiographic methodology presently available is adequate to detect changes in hip JSW of OA.
|
|
| 10. |
- Boegard, T.L., et al.
(författare)
-
Magnetic resonance imaging of the knee in chronic knee pain. A 2-year follow-up
- 2001
-
Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 9:5, s. 473-480
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim of the study was to evaluate the change over time of cartilage defects, subchondral lesions and meniscal abnormalities of the knee using magnetic resonance (MR) imaging with a 2-year interval in patients with chronic knee pain. Design: In the format of a prospective study of early osteoarthritis (OA), the signal knee (most painful at the inclusion in the study 1990) in 47 individuals, 25 women and 22 men (aged 41-57 years, median 50), with chronic knee pain, with or without radiographically determined knee OA, were examined using MR imaging on a 1.0 T imager with a 2-year interval (median 25 months, range 21-30). Cartilage defects, subchondral lesions and meniscal abnormalities were recorded and compared in blind between the examinations. Results: Five new cartilage defects and eight subchondral lesions appeared during the 2-year interval. Seven defects and seven subchondral lesions disappeared during the same time. Thirty-two out of 93 cartilage defects (34%) and 19 out of 32 subchondral lesions (59%) displayed an increase or a decrease in size over time. A meniscal abnormality appeared in three locations, and disappeared in none. In 14 out of 54 locations (26%) with a meniscal abnormality an increase or a decrease of the abnormality was recorded over time and no abnormality decreased. Conclusions: After the 2 years of observation it was possible to register, using MR imaging, the appearance, increase, decrease and disappearance of cartilage defects, subchondral lesions and meniscal abnormalities in middle-aged people with chronic knee pain. This has to be considered in studies of the natural course of knee CA as well as in studies of the intraarticular effect of pharmacological treatment aiming at cartilage repair or protection.
|
|
