Department of Anatomy, Division of Basic Medical Science, Tokai University School of Medicine, Kanagawa, Japan.
Department of Anatomy, Aichi Medical University, Aichi, Japan.
Folia Morphol (Warsz). 2022;81(2):493-502. doi: 10.5603/FM.a2021.0019. Epub 2021 Feb 26.
The incidence of an elongated styloid process (SP) and average length and diameter of SP have not been reported using Japanese cadavers. Data on the female-to-male ratio of an elongated SP vary. We calculated the average length and diameter of SP in Japanese cadavers and compared SP lengths between sexes.
Twenty-seven sides (right and left of bodies) in males and 51 sides in females were analysed. Measurements were obtained from the inferior external acoustic meatus to the distal tip of the SP. SP diameters at the proximal base, midpoint, and distal tip were measured. SP > 30 mm was considered elongated. We used Welch's t-test for the statistical analysis. Fisher's exact two-tailed test was also performed to analyse the female-to-male elongation ratio. A p-value < 0.05 was considered statistically significant.
Styloid process elongation prevalence was 29.5% in our sample. The average full length was 27.04 ± 7.88 mm overall; the average diameters were 5.41 ± 1.77 mm at the proximal base and 2.21 ± 1.22 mm at the distal tip. The average SP measurement was 26.81 ± 5.92 mm in males and 27.16 ± 8.79 mm in females (p = 0.74). The female-to-male ratio of SP elongation was 1:2 (p = 0.041). Females had longer full lengths of non-elongated SPs than males (p = 0.004). Males had wider diameters at the proximal base of elongated SPs than females (p = 0.017).
The average length of SP was 27.04 mm in the Japanese population and about 30% of the Japanese presented SP ≥ 30 mm. Male had significantly higher rate than female among the SP ≥ 30 mm, and female had significantly longer SPs than male among the SP < 30 mm. Anatomically, the SP gets narrow as distally goes. Our anatomical findings would be beneficial to creating treatment plans, diagnosis, and surgery.
使用日本尸体尚未报道过长茎突（SP）的发病率以及 SP 的平均长度和直径。关于长茎突的男女比例的数据也各不相同。我们计算了日本尸体中 SP 的平均长度和直径，并比较了男女之间的 SP 长度。
分析了男性尸体的 27 侧（左右）和女性尸体的 51 侧。测量从外耳道口下到 SP 的远端尖端。测量 SP 在近端基底、中点和远端尖端的直径。SP > 30mm 被认为是伸长的。我们使用 Welch's t 检验进行统计分析。Fisher's 精确双侧检验也用于分析女性与男性伸长率的比值。p 值<0.05 被认为具有统计学意义。
在我们的样本中，SP 伸长的患病率为 29.5%。总体平均全长为 27.04±7.88mm；平均直径近端基底为 5.41±1.77mm，远端尖端为 2.21±1.22mm。男性 SP 平均测量值为 26.81±5.92mm，女性为 27.16±8.79mm（p=0.74）。SP 伸长的女性与男性比例为 1:2（p=0.041）。非伸长 SP 的女性全长长于男性（p=0.004）。男性伸长 SP 的近端基底直径大于女性（p=0.017）。
日本人群中 SP 的平均长度为 27.04mm，约 30%的日本人 SP≥30mm。在 SP≥30mm 中，男性的发生率明显高于女性，而在 SP<30mm 中，女性的 SP 明显长于男性。解剖学上，SP 越远越窄。我们的解剖学发现将有助于制定治疗计划、诊断和手术。
