ABSTRACT
Objective To discuss the morphological features of the fifth metacarpal bone and clinical significance by measuring the three-dimensional (3-D) reconstruction model, and to improve the clinical technique and surgical instruments. Methods A total of 114 3-D reconstruction models based on computed tomography data of fifth metacarpal bone were created. The length, the radius of head, the radius of arc, the 1/ 2 central angle of arc, the distance of head offset, the ratio of head offset, the inner diameter of the isthmus of medullary space were measured based on 3-D models. Results The fifth metacarpal bone length was(51. 55±3. 01) mm. The radius of the fifth metacarpal head was (6. 59± 0. 49)mm. The radius of the fifth metacarpal bone arc was(99. 58±26. 83)mm. The 1/ 2 central angle of fifth metacarpal bone arc was(15. 90±3. 36)°. The distance of the fifth metacarpal head offset was(0. 49±0. 26) mm. The ratio of head offset was(7. 4±3. 9)%. The inner diameter of the isthmus of medullary space was (2. 28±0. 77)mm. Conclusion The length, the radius of head, the distance of head offset, the inner diameter of the isthmus of medullary space are different between male and female, and the other parameters are not different. There is no significant difference between left and right hand.