Torsional Characteristics between Single and Double Distal Screws in the Interlocking Intramedullary Nailing of Humeral Shaft Fracture / 대한정형외과연구학회지

The use of interlocking intramedullary nail is accepted one of treatment choices in the comminuted fractures of humeral shaft. The insertion of distal interlocking screws remains technically problematic. The use of intrageon's hands during the procedure. In order to reduce technical difficulty and radiation exposure, it is necessary to compare the rigidity of intramedullary nail according to the number of distal interlocking screws. The purpose of study is to compare the stability of interlocking intramedullary nail according to the number of distal screws by means of torsional compliance measurements in the simulated humeral shaft fractures. Simulated fractures were made in 20 humora from 10 cadavera at the mid-junction of humeral shaft. All humora were fixated with titaium humeral nail system. Interlocking screws were placed at proximal and distal screw holes by standard procedure. Group I consisted of 10 humora fixated with one distal interlocking screw and group II consisted of 10 humora fixated with two distal intterlocking screws. Torsional compliance was measured with single-end of 10 humora fixated with two distal interlocking screws. Torsional compliance was measured with single-end double arm torquing machine. The torsional compliance analog was 0.0294+/-0.0033 mm/N mm for one screw and 0.0241+/-0.0045 mm/N mm for two distal screws. The torsional compliance analog between two groups was found to be statistically insignificant(p=0.23). In conclusion, One distal interlocking screw was not inferior to two interlocking screws in terms of biomechanical characteristics, especially torsional compliance analog.

Study on Hepatic Injury following Occlusion of Hepatic Inflow in Rabbits / 대한마취과학회지

BACKGROUND: Portal triad clamping was first described by Pringle in 1908 as a mean of reducing bleeding from the cut surface of the liver during parenchymal resection. More recently some studies have reported that one period of portal triad clamping could be well tolerated for a longer duration, 60~90 minutes. The liver, generally, is believed to be very sensitive to anoxic damage and susceptible to ischemia and decreased hepatic energy charge results in decreasing arterial ketone body ratio (AKBR) during portal triad clamping. METHODS: In order to observe an adverse effects to liver in 30 minutes and 60 minutes of portal triad clamping on AKBR and histologic changes,rabbits were divided into thirty minutes of portal triad clamping in one group (Group I) and 60 minutes of that in the other group (Group II). RESULTS: During clamping, the mean AKBR of group I and II were 0.39 and 0.44, and decreased significantly compared with the mean AKBR (1.08 and 1.02) before clamping. Five minute after declamping, the mean AKBR of group II (0.49) was lower (P0.05). Under light microscopic examination of liver biopsy, there was no visible diffrences between two groups during clamping, 5 minutes and 30 minutes after declamping. CONCLUSIONS: It was concluded that there was no difference in hepatic energy change(AKBR) and histologic change under light microscopy after 30 minutes declamping between two groups.