Analysis of Biomechanics about Interosseous Sacroiliac Ligament

Objective To find out what function does the interosseous sacroiliac ligament have in keeping sacroiliac joint stable.Methods Twenty-four normal adult wet pelvis specimens were put into experiment,severed the synchondroses pubis of the every pelvis speciment,took randomly the left or right hemi-pelvis as the control side,the other hemi-pelvis as the test side,created injuried models by sever the interosseous sacroiliac ligaments of the test side throught the middle.Divided the speciments into four groups,after fix the pelvis to the biomechanics test machine,put pressure to the control side and test side sacroiliac joints through four directions:fore-and-aft direction,vertical direction,intorsion direction and extorsion direction.The pressure to the sacroiliac joint was from lower to higher,each time add 10N,when the sacroiliac separated,record the max pressure(unit N) .Analyzed the pressure data by the SSPS13 statistical software,and found out what function does the interosseous sacroiliac ligament have in keeping sacroiliac joint stable.Results The pressure that the test sides of the sacroiliac joint could beared through fore-and-aft direction,vertical direction and intorsion direction was much lower than the control sides,The difference was statistically significant(P0.05) .The pressure that the test sides of the sacroiliac joint could beared through extorsion direction was a little lower than the control sides,The difference was not statistically significant(P0.05) .Conclusion The interosseous sacroiliac ligament play an important role in keeping the sacroiliac joint stable,it can prevent the sacroiliac joint from displacement in fore-and-aft direction,vertical direction and intorsion direction.