Human chondrocytes in tridimensional culture.

peer reviewedCartilage was taken from the macroscopically normal part of human femoral heads immediately after orthopedic surgical operations for total prothesis consecutive to hip arthrosis. After clostridial collagenase digestion and repeated washings, chondrocytes (10(6) cells) were cultivated in a gyrotory shaker (100 rpm). Under these conditions, cells were kept in suspension and after 3 to 5 d formed a flaky aggregate which, on Day 10, became dense. These chondrocytes were morphologically differentiated: they had a round shape, were situated inside cavities, and were surrounded by a new matrix. Histochemical methods showed the presence of collagen and polysaccharides in cell cytoplasm and in intercellular matrix, and the immunofluorescence method using specific antisera (anticartilage proteoglycans and anti-type II collagen) showed that these two constituents were in intercellular matrix. The measurement of the amounts of proteoglycans (PG) released into culture medium and those present in chondrocyte aggregate (by a specific PG radioimmunoassay) showed a maximum production on Days 3 to 5 of culture, then the production decreased and stabilized (from Day 10 to the end of culture). The observed difference between the amounts of PG in aggregates after 20 d and those after 2 h of culture demonstrated that PG neosynthesis did occur during cultivation. This conclusion was supported by other results obtained by [14C]glucosamine incorporation in chondrocyte aggregates. Moreover, the aggregate fresh weight related to cell number (appreciated by DNA assay) increased significantly with culture duration. Three-dimensional chondrocyte culture represents an interesting model: chondrocytes were differentiated morphologically as well as biosynthetically and synthesized a new cartilage matrix

Pulsed electromagnetic fields after arthroscopic treatment for osteochondral defects of the talus: double-blind randomized controlled multicenter trial

Background. Osteochondral talar defects usually affect athletic patients. The primary surgical treatment consists of arthroscopic debridement and microfracturing. Although this is mostly successful, early sport resumption is difficult to achieve, and it can take up to one year to obtain clinical improvement. Pulsed electromagnetic fields (PEMFs) may be effective for talar defects after arthroscopic treatment by promoting tissue healing, suppressing inflammation, and relieving pain. We hypothesize that PEMF-treatment compared to sham-treatment after arthroscopy will lead to earlier resumption of sports, and aim at 25% increase in patients that resume sports. Methods/Design. A prospective, double-blind, randomized, placebo-controlled trial (RCT) will be conducted in five centers throughout the Netherlands and Belgium. 68 patients will be randomized to either active PEMF-treatment or sham-treatment for 60 days, four hours daily. They will be followed-up for one year. The combined primary outcome measures are (a) the percentage of patients that resume and maintain sports, and (b) the time to resumption of sports, defined by the Ankle Activity Score. Secondary outcome measures include resumption of work, subjective and objective scoring systems (American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale, Foot Ankle Outcome Score, Numeric Rating Scales of pain and satisfaction, EuroQol-5D), and computed tomography. Time to resumption of sports will be analyzed using Kaplan-Meier curves and log-rank tests. Discussion. This trial will provide level-1 evidence on the effectiveness of PEMFs in the management of osteochondral ankle lesions after arthroscopy. Trial registration. Netherlands Trial Register (NTR1636)