Viability Of Articular Cartilage Research Articles

The use of a hyperosmolar irrigation solution is safe in an equine stifle joint model but does not reduce joint swelling.

To determine the following: (1) whether an irrigation solution that is hyperosmolar (HYPER) relative to synovial fluid decreases tissue extravasation during an arthroscopic protocol when compared to a relatively hypoosmolar solution, (2) the safety of a HYPER solution based on viability of joint tissues following joint irrigation, and (3) if the use of a HYPER solution decreases water content in stifle joint tissue. 8 adult horses. A prospective, blinded, randomized controlled trial was performed to compare lactated Ringer's solution (LRS; 273 mOsm/L) and a HYPER (600 mOsm/L) irrigation solution for routine medial femorotibial joint (MFTJ) arthroscopy. Primary outcomes included quantification of periarticular fluid retention based on measured changes in defined stifle joint girth and ultrasonographic (US) criteria. Water content of tissue samples was assessed. The viability of articular cartilage was determined using a microscopic fluorescent cell viability staining system. No significant difference in postprocedural joint swelling was observed between LRS and HYPER treatment groups. Percent increments in femorotibial joint dimensions (mean ± SD) were seen in both treatment groups based on US (LRS, 83.9 ± 84.6%; HYPER, 131.2 ± 144.9%) and caliper measurements (LRS 5.5 ± 4.3%; HYPER 7.5 ± 5.8%) (P ≤ .05). Chondrocyte viability and tissue water content were maintained in both treatment groups, and differences were not statistically significant. Doubling the osmolarity of an irrigation solution used routinely for arthroscopy does not result in detrimental effects on chondrocyte viability or tissue water content. However, use of a relatively HYPER irrigation solution did not attenuate procedural tissue swelling of the equine stifle joint.

The Influence of a Single Intra-Articular Lidocaine Injection on the Viability of Articular Cartilage in the Knee.

To evaluate the in vivo effect of a single intra-articular injection of local anesthetic (LA) lidocaine on the viability of articular cartilage in the intact or osteoarthritic (OA) human knees, and to measure the synovial postinjection concentration of lidocaine in the knee. This study includes 3 interconnected experiments: (A) Synovial LA concentration measurement after a 2% lidocaine injection before knee arthroscopy in 10 patients by liquid chromatography-tandem mass spectrometry (LC-MS/MS). (B) Human osteochondral explants (N = 27) from intact knees procured at autopsies were incubated for different time intervals (30 minutes, 2 hours, 24 hours) with 2% lidocaine, 0.04% lidocaine (measured), or culture medium (control), and later evaluated for cell viability by LIVE/DEAD staining. (C) Ten out of 19 matched patients scheduled for knee replacement received a single intra-articular injection of 2% lidocaine approximately 30 minutes prior to the procedure; 9 patients served as control. Osteochondral samples with OA changes were harvested during surgery and analyzed for chondrocyte viability by LIVE/DEAD staining. (A) The synovial LA concentration was significantly lower than the primary concentration injected: average 0.23 mg/mL (0.02%), highest measured 0.37 mg/mL (0.04%). (B) In vitro exposure to a reduced LA concentration had no significant influence on chondrocyte viability in intact cartilage explants (24-hour averages: control, 93%; 0.04% lidocaine, 92%; 2% lidocaine, 79%). (C) Viability of chondrocytes in OA knees was similar between 2% lidocaine injection (85%) and control (80%). A single intra-articular knee injection of 2% lidocaine did not influence the chondrocyte viability neither in healthy nor in OA cartilage. A fast postinjection reduction of synovial LA concentration (more than 40 times) is the most likely protective mechanism.

Post-arthroscopic elbow chondrolysis after continuous intra-articular ropivacaine infusion

Post-arthroscopic chondrolysis is a rare but well documented complication with devastating consequences. Although the etiology appears to be complex, it is associated with thermal and chemical insult that affects the viability of articular cartilage and chondrocytes. Findings occur within weeks to months of the inciting event and include a progressively painful joint, loss ofmotion, rapid and progressive loss of joint space, subchondral edema, and lack of periarticular osteophytes. Most reports of post-arthroscopic chondrolysis have involved the glenohumeral joint after the use of intra-articular thermal devices or continuous infusion pain catheters. To our knowledge, this is the first report of post-arthroscopic chondrolysis of the elbow joint and the first case of ropivacaine-associated chondrolysis. The patient was informed that data concerning the case would be submitted for publication, and consent was granted.

The proteoglycan metabolism, morphology and viability of articular cartilage treated with a synthetic matrix metalloproteinase inhibitor.

Matrix metalloproteinases (MMP) are among the key enzymes responsible for the proteolytic destruction of articular cartilage during chronic rheumatic diseases. Articular cartilage is one potential target for drugs designed to inhibit the activity of MMPs in order to stop or to slow down the proteolytic destruction of the extracellular matrix of cartilage. The purpose of this study was to investigate the effect of the synthetic inhibitor of MMPs U-24522 for its ability (1) to inhibit in vitro the activity of MMP-proteoglycanases; (2) to modulate the morphology and viability of cartilage explants; and (3) to modify the biosynthesis and release of proteoglycans from articular cartilage explants. U-24522 dose-dependently inhibited the activity of MMP-proteoglycanases and significantly reduced the release of proteoglycans from interleukin-1 treated bovine articular cartilage explants when tested at concentrations ranging from 10(-4) to 10(-9) M. This hydroxamic acid derivative proved not to be harmful to chondrocyte viability and cartilage morphology. In addition, U-24522 had no effect on the rate of proteoglycan biosynthesis of interleukin-1 treated cartilage explants and increased the percentage of newly synthesized proteoglycans to form macromolecular aggregates. Thus U-24522 combines direct inhibitory potential on the activity of MMP-proteoglycanases with the inhibition of interleukin-1 stimulated proteoglycan loss from articular cartilage explants without affecting the morphology, viability and biosynthesis of proteoglycans of bovine articular cartilage explants.

The viability of articular cartilage in fresh osteochondral allografts after clinical transplantation.

The articular cartilage of four fresh osteochondral allografts was biopsied after transplantation, and its viability was studied by autoradiography. The biopsy specimens were labeled with both 3H-cytidine, for newly synthesized ribonucleic acid, and 35S-sulphate, for newly synthesized proteoglycans. The cartilage of a lateral humeral condylar graft at twelve months had 96 to 99 per cent labeled chondrocytes, the articular cartilage of a medial femoral condylar graft at twenty-four months showed 69 to 78 per cent labeled chondrocytes, and the cartilage of a medial tibial-plateau graft at forty-one months had 90 per cent labeled cells. At six years, a lateral tibial-plateau graft had 37 per cent labeled chondrocytes.

Clinical Experience with Allograft Implantation

From 1971 to 1982, 110 osteochondral transplants with follow-up evaluation were performed for treatment of skeletal deficits caused by degenerative, traumatic, and neoplastic diseases largely involving the knee joint. Seventy-eight small-fragment fresh allografts were transplanted for repair of old tibial plateau osteochondral fractures, osteonecrosis, and unicompartmental osteoarthritis. Thirty-two large-fragment grafts were performed following en bloc excision of bone tumors. Of these, 22 were allografts, three were vascularized fibular autografts, and seven were a combination of allografts and vascularized fibular autografts. In this large-fragment group, three grafts have been removed for tumor recurrence, two for infection, and one for a stress fracture. The results of these transplants have proved particularly rewarding in the old plateau fractures, for traumatic loss of bone and cartilage (osteonecrosis), and after en bloc excision of giant cell tumors.