The Design Experiment And Animal Experiment Of The Sliding Lock Biology Blade Plate

Objective: Design one kind of the sliding lock biology blade plate, solve the bladeplate’s stress shielding and promote fracture healing.Method:The sliding lock biology blade plate set locking structure at an end,the blateplate’s sliding end has sliver inner arc trough. The arc trough has the flat oval lockingblock and taper locking hole,when taper head of locking nail screws tight,locking blockthickness,The outer annulus of the locking block combines together with the sliver inner,arc trough,locking nail no longer skids and revolves.In mechanics experiments, the bothside fresh pairing femoral bone of24goats, made it cross-sectional fracture model,assigned to three groups averagely, fixed respectively with6-hole lock biological boneplate,6-hole non-contact pressure bone plate,6-hole sliding lock biology blade plate,produce three groups of test model that each kind of bone plate were fixed withrespectively1.5KG,2.5KG,4.5KG three different torque wrench. Fracture specimenswere placed in multi-function mechanics test machine for four-point bending test andtorsion test. In animal experiments, self-control contrast method were used in theexperiment, the bilateral femur of12goats were randomly fixed using the sliding lockbiology blade plate or lock biological bone plate. The other bilateral femur of12goatswere randomly fixed using the sliding lock biology blade plate or non-contact pressurebone plate, retain fracture gap2mm.we put goats to death in postoperative4,8,12weeks,eight goats in every time, of which the fixed fractureal segment of two goats were madethe histological observation, and the other six goats were take out bilateral femoral andmade X-ray and biomechanical testing.Results:The results of mechanical experiments:1. The four-point bending test: whenusing4.5KG torque wrench fixed various bone plate, the load between fracture ends ofthree kinds bone plates was respectively110KG,174KG,141KG, but no significant difference among the three bone plates (p＞0.42). When the torque decreased, there was noapparent influence in the lock bone plate and pressure bone plate. And sliding lock biologyblade plate appeared change significantly, and compared with the former two bone plates,there were significant differences (p <0.05).2. The torsion test: when torsion Angleincreased to15°, torque was40NM to stop the test. The three kinds of bone plate torquedifference was obvious (double factor analysis of variance F=105.503, P <0.05).and thetorque of the lock bone plate and pressure bone plate, there was no significant difference (P>0.05); Compared with the former two bone plates, the torque of the sliding lock biologyblade plate is significant difference (P <0.05). The results of animal test:1. Imagingobservation: Compared with the other two bone plates,the fracture line of the slidinglock biology blade plate group was fuzzy、disappear after4weeks and8weeks, thefracture end in the three kinds of bone plate was good healing after12weeks.2. Mechanicsexperiment In postoperative4weeks and eight weeks,the resistance torque strength ofthe sliding lock biology blade plate were significantly greater than the lock bone plategroup and no-contact pressure bone plate group (matching t test, p <0.05). Inpostoperative12weeks, the resistance torque strength of three kinds of bone plate had nosignificant difference.3.Histological observation: In postoperative4weeks and8weeks,the fracture healing rate and the quality in the sliding lock biology blade plategroup was superior to lock bone plate group and no-contact pressure bone plate group, Inpostoperative12weeks, the lock bone plate group and no-contact pressure bone plategroup had neat lamellar bone structure, haversian system arrangement neat, appeared moreobvious bone resorption cavity, the sliding lock biology blade plate group appeared maturebone unit, a small bone resorption cavity.Conclusion:The sliding lock biology blade plate had continuous effective pressure infracture ends, had the good biological mechanics performance; the fracture healingspeed and quality are better than traditional bone plate.