目的:建立妊娠中期和妊娠晚期人体锤骨的正常参考值,并描述了其生长动力学和骨化过程。
方法:30例自然流产的人类胎儿,12-36周龄,进行了检查。整体获得颞骨,并使用骨骼清除和染色技术进行处理。通过显微解剖获得每个锤骨。进行锤骨解剖点的测量。记录骨化。统计应用。
结果:共获得60个弹丸。在发展的最后,以毫米为单位获得以下测量值:头部长度,2.87(2.30-3.44);颈部长度,1.15(0.92-1.38);柄长,4.45(3.75-5.16);总长度,8.51(8.02-8.99);颈部宽度,1.33(0.70-1.97);柄部宽度,0.84(0.82-0.86);和Meckel软骨宽度,0.43(0.06-0.95)。锤骨的纵轴的角度为160°(156-164°)。锤骨的骨化过程遵循从第16周开始的刻板模式,在颈部水平,一个中心扩展到头部,然后扩展到胸罩。在发展的尽头,只有umbo保持软骨。在产前发育期间,人类锤骨大小没有基于性别的差异。从怀孕中期开始,锤骨的纵轴获得与成年人相当的尺寸。
结论:对锤骨发育的研究提供了线索,可以解释其发育中的某些异常,并且可以在锤骨中假体的放置和设计过程中影响决策。
OBJECTIVE: Establish normal reference values for the human
malleus during the second and third trimesters of pregnancy, and describe its growth dynamics and ossification process.
METHODS: Thirty spontaneously aborted human fetuses, 12-36 weeks of age, were examined. Temporal bones were obtained en bloc and processed using the skeletal clearing and staining technique. Each
malleus was obtained by microdissection. Measurements of anatomical points of the malleus were performed. Ossification was recorded. Statistics were applied.
RESULTS: Sixty mallei were obtained. At the end of development, the following measurements were obtained in millimeters: head length, 2.87 (2.30-3.44); neck length, 1.15 (0.92-1.38); manubrium length, 4.45 (3.75-5.16); total length, 8.51 (8.02-8.99); neck width, 1.33 (0.70-1.97); manubrium width, 0.84 (0.82-0.86); and Meckel cartilage width, 0.43 (0.06-0.95). The angle of the longitudinal axis of the
malleus was 160° (156-164°). The ossification process of the malleus followed a stereotyped pattern that began at week 16, at the level of the neck, with a single center that expanded to the head and then to the manubrium. Toward the end of development, only the umbo remained cartilaginous. There were no sex-based differences in human
malleus size during prenatal development. From the beginning of the second trimester of pregnancy, the longitudinal axis of the malleus acquires dimensions comparable to adults.
CONCLUSIONS: The
study of the
malleus development provides clues that would explain some anomalies in its development, and can influence decision-making during the placement and design of prostheses in the malleus.