A Anatomic Study About Dorsoradial Dislocation Of The First Carpometacarpal Joints And Analysis Of Mechanics

ObjectiveTo study the course, adjacence, appearance and structure characteristic of the carpometacarpal joint of the thumb, investigate anatomical basis of the carpometacarpal joint dislocation of the thumb and to provide a anatomical accordance for clinical diagnosis and treatment.Method12 adult forearm without deformity and trauma were obtained. Dissect and observe the courser, adjacence, appearance and structure characteristic of the carpometacarpal joint of the thumb, study the ligaments around the the carpometacarpal joint of the thumb and make a mechanics assessment of ligaments preventing dorsoradial dislocation of the carpometacarpal joint of about the thumb, especially make a difference of the dorsal oblique ligament and radial dorsal ligament. Microscope (2.5×).measure the length, width, thickness of the five ligments and make a biomechanical assessment of ligaments preventing dorsoradial dislocation of the carpometacarpal joint about the thumb. The data were processed by SPSS 13.0 software. The dorsal oblique ligament and radial dorsal ligament were paid attention to.ResultsThe ligaments around the carpometacarpal joint of the thumb are very complicated, include: dorsal oblique ligament, radial dorsal ligament, anterior oblique ligament , intermetacarpal ligament, anterior oblique ligament. Observing these ligaments, we found dorsal ligaments around the joint are stronger and found radial dorsal ligament plays an more important role in preventing dorsoradial dislocation of the carpometacarpal joint about the thumb than dorsal oblique ligament after analysis of mechanics between them.Conclusion:The dorsal ligaments play an important role in stabilizing the carpometacarpal joint of the thumb, especially RDL .We should pay attention to repairing dorsal ligaments.