Saeed Muhammad, Murshid Khalid R, Rufai Amin A, Elsayed Salah E, Sadiq Muhammad S
Department of Anatomy, College of Medicine and King Khalid University Hospital, King Saud University, Riyadh, Kingdom of Saudi Arabia.
Saudi Med J. 2002 Oct;23(10):1214-21.
To study the prevalence of sternalis muscle in the Kingdom of Saudi Arabia (KSA) and resolve the question of its genesis by studying the innervation of this uncommon variant of anterior chest wall musculature.
A morphological study of 75 adult cadavers of both sexes was carried out over a 5-year period by macroscopic dissection. We also retrospectively studied the medical records of 1580 adult females who had undergone screening and diagnostic mammographic imaging at King Khalid University Hospital, Riyadh, KSA, from 1997 to 2001.
Out of 75 cadavers studied, 3 cases of sternalis muscle were observed. Two adult male cadavers had well developed bilateral sternalis muscles whereas one female cadaver exhibited right sided unilateral sternalis. All 5 sternalis muscles were positioned vertically, in a parasternal position superficial to the medial part of pectoralis major and innervated by branches of intercostal nerves. None of the 1580 women, however, who had undergone mammographic imaging were found to be sternalis positive.
Consistent with other geographic populations of the world, the frequency of sternalis in KSA is approximately 4%; however, its innervation by the intercostal nerves, as observed in our study is not common. This study highlights the need for familiarity with sternalis, which may mimic a focal density in medial breast craniocaudal mammograms and may be encountered during reconstructive surgery of breast and chest wall.
研究沙特阿拉伯王国（KSA）胸骨肌的患病率，并通过研究这种不常见的前胸壁肌肉组织变异体的神经支配来解决其起源问题。
在5年时间里，通过宏观解剖对75具男女成年尸体进行了形态学研究。我们还回顾性研究了1997年至2001年期间在沙特阿拉伯利雅得国王哈立德大学医院接受乳腺筛查和诊断性乳房X线摄影成像的1580名成年女性的病历。
在研究的75具尸体中，观察到3例胸骨肌。两具成年男性尸体双侧胸骨肌发育良好，而一具女性尸体右侧有单侧胸骨肌。所有5块胸骨肌均垂直位于胸骨旁位置，在胸大肌内侧部分的浅面，由肋间神经分支支配。然而，在接受乳房X线摄影成像的1580名女性中，没有发现胸骨肌阳性的情况。
与世界其他地理区域的人群一致，沙特阿拉伯王国胸骨肌的出现频率约为4%；然而，正如我们研究中所观察到的，其由肋间神经支配并不常见。这项研究强调了熟悉胸骨肌的必要性，因为它可能在乳房头尾位乳房X线片中模拟乳腺内侧的局灶性密度，并且在乳房和胸壁重建手术中可能会遇到。
