Purified xenogeneic cartilage matrix components, including proteoglycan subunits, chondroitin 4 sulfate, and chondroitin 6 sulfate, were inoculated into the knee joint of rabbits, and local as well as systemic responses were evaluated. proteoglycan was associated with synovial hyperplasia and infiltrates of eosinophils and lymphocytes and with rising titers of antiproteoglycan antibodies in a tanned sheep rbc hemagglutination assay over a six-week period of weekly intra-articular injections and observations. Chondroitin sulfates failed to evoke detectable changes in the joint or serum. Immunogenicity of cartilage matrix components may play a role in allogeneic and xenogeneic osteochondral grafts, and it is also possible that autogenous matrix immunogens exist and contribute to progression of degenerative joint disease. The immunogenicity of allogeneic and autogenous cartilage matrix components remains undefined.

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PubMedDate not supplied

Thromboembolism after surgical treatment of hip fractures.

Seventy-five patients ages 40 to 95 (average, 78), 60 of whom were women and 15 men, were admitted with upper femoral fractures and participated in a study designed to evaluate the possible prophylactic effects of platelet-inhibiting drugs on the incidence of thromboembolism. Aspirin, 600 mg, b.i.d., or a combination of the above doses of aspirin and hydroxychloroquine, 300 mg, b.i.d., were used from the time of admission. The study was prospective, consecutive except for a few exclusions, double-blind and randomized. Standard surgical treatment was given by three orthopedists. Venography by the 11th day was the endpoint, although daily examinations and early impedance plethysmography were also used. Twenty-five patients received placebos, 24 aspirin alone and 26 aspirin and Plaquenil. In the control group, 15 of 25 (60%) developed thrombosis and two had nonfatal pulmonary emboli. With aspirin, six of 24 (25%) had thrombosis and one a fatal embolus. In the combination group seven of 26 (27%) developed thrombosis and there were no emboli. No significant difference existed between treatment groups, but there was significant difference between the control and treatment group at the 2% level by the Yates chi2 test. Treated women received significant protection against thromboses (p less than 0.02); 13 of 20 untreated women had deep thromboses versus 12 of 40 in the treated women. Aspirin prophylaxis is significantly useful in fractured hip patients. The combination of aspirin and Plaquenil offers no additional benefit and only leads to complications from hematomas.

Adult↗

PubMedDate not supplied

1981 Nicolas Andry Award. The relationship of mechanical trauma and the early biochemical reactions of osteoarthritic cartilage.

Using a computerized pendulum device for delivery of a moderate, reproducible impact on the surface of canine femoral cartilage, the lipids of the cartilage were analyzed by gas chromatography, and a four-fold increase in arachidonic acid was found in the phospholipid pool, as compared with controls. This is the first evidence presented thus far which clarifies the link between mechanical injury and the early biochemical changes of the osteoarthritic process. Electron microscopy of impacted cartilage cells showed an increase in lipids and microtubules and cytoplasmic derangement. There was a brief rise in hexosamine content soon after impaction, followed by a trend toward loss.

Animals↗