ABSTRACT
Experimental dysbaric osteonecrosis associated with inadequate decompression has been induced in mature female swine. The bone collagen from the radiologically defined lesion in the femur has been analyzed. The total collagen contents were the same for the epiphyseal (F-1), the metaphyseal (F-2), and the diaphyseal (F-3) regions. Soluble bone collagen content obtained by sequential extraction of the samples with acetic acid urea, guanidine, lithium chloride and potassium thiocyanate, decreased by approximately 20% in going from the F-1 to the F-2 to the F-3 regions for both experimental and control samples. The amino acid compositions and acrylamide gel electrophoresis patterns were the same for control and experimental samples. Spectral changes with the MBTH reaction were different for control and experimental collagen samples from all bone regions. The spectral shift and pattern changes which occurred from pH 4 to pH 1 suggested a higher average content of unsaturation in the collagen associated aldehyde groups in the experimental than in the control samples. These findings suggest an enhanced ability to remodel collagen which would be consistent with the histological observation of increased derangement of collagen fibers in the experimental bone samples.
