Osteomedullography in estimating the consolidation of long bone fractures in the dog

Six canine long bone fractures with delayed or non-union were investigated using osteomedullography. The contrast medium crossed the fracture (positive osteomedullography) in four cases. All contrast medium remained in the distal fragment (negative osteomedullography) in two cases. The fractures with the negative finding were operated upon using bone grafts. Conservative fracture treatment using transfixation or plaster cast was continued in the positive cases. All the fractures united from 9 to 15 weeks after the examination and treatment. Osteomedullography proved to be a reliable method for identifying which non-union fractures require further operative treatment for healing.     

ACCUMULATION OF SULPHUR IN AND ON SCOTS PINE NEEDLES IN THE SUBARCTIC

Total S concentrations of Scots pine (Pinus sylvestris L.) needles studied in the Finnish subarctic (66–70°N, 24–30°E) in 1990/1992 ranged from 573 to 1153 μg g^-1. Levels were found to be ≈ 900 μg g^-1 (i.e. 1.3–1.8 times the ‘normal’ level of 500–700 μg g^-1) in areas where the long-term ambient SO₂ concentration was ≈ 2–5 μg m^-3, particulate SO₄ ^2- ≈ μg m^-3 and total S deposition ≈ 0.5 g m^-2. A statistically significant increase in needle total S concentrations was found towards the east, i.e. towards the smelters of the Kola Peninsula in Russia, which emit SO₂. The increase in needle total S concentrations to over 900 μg g^-1 close to the Russian border is thought to result mainly from exposure to high short-term SO₂ concentrations. The results also suggest that wintertime S deposition may have an impact on the needle total S content. It is suggested that the UNECE long-term critical level of 15 μg SO₂ m^-3 for forestry in boreal and high mountain climates in Europe is too high for the pine forests in the extreme north, where the proportion of dry-deposited S may be 60–80%.