OBJECTIVE: To provide a new method to estimate t he effectiveness of thoracolumbar vertebral finite element model. METHODS: A mechanical model of human thoracolumbar vertebrae mo tion segment was made using three-dimensional finite element method and the str ess distribution of vertically compressed thoracolumbar vertebrae was analyzed, meanwhile, 20 patients with burst fracture of thoracolumbar vertebrae were t ested by CT to calculated average CT value at ascertained different points of th oracolumbar vertebrae. The calculated results and effective stress at the same p osition were analyzed with straight line correlation. RESULTS: The stress level of different position of thoracolumba r vertebrae under vertical compressive force was positively correlated with the correlative CT value, and the regressive style, Y=214.028+45.268X, r=0.7386, P<0.05 (n=8) showed a statistical significance. CONCLUSIONS: To study mechanism of thoracolumbar vertebrae in juries under different forces has clinical significance.

OBJECTIVE: To observe the revascularization and the opportunity of cross-finger flap. METHODS: An animal model was developed to permit daily monit oring of neovascularization of the flap with autoradiography, tissue transparent technique, gross observation and histological examination. RESULTS: The revascularization of the flap was chiefly raised f rom the surrounding tissues. The pedicles of 334 cross-finger flaps of the pati ents were successfully divided from 1 to 5 d after operations, averagely 3. 3 d. All of the cases showed satisfatory results according to a follow-up sur vey of 3 to 72 mon. The results further proved that the revascularization of the cross-finger flaps had accomplished within 3 d. CONCLUSIONS: It suggests that the division of a cross-finger f lap can be carried out between the 3rd and 5th day after operation with a high d egree of safety.