St. James's University Hospital, Leeds Teaching Hospitals Trust, Beckett St, Leeds, United Kingdom.
Clin Anat. 2011 Jan;24(1):70-6. doi: 10.1002/ca.21053. Epub 2010 Nov 10.
Preservation of piriformis during exposure of the hip joint via a posterior approach may result in a lower rate of dislocation following total hip arthroplasty. The aim of this study was to identify anatomical variations in the tendons of piriformis and obturator internus which could inform piriformis sparing approaches to the hip. Twenty-nine proximal femora from 15 cadavers, 5 male and 10 female aged 65-79 years, were examined. Tendon crossing angles, location and mode of insertion to the greater trochanter and the extent of fusion between tendons prior to insertion were noted. The mean (and associated standard deviation) of the vertical and horizontal widths of the piriformis tendon were 4.78 ± 1.31 mm and 7.35 ± 1.74 mm, respectively. The mean (and associated standard deviation) of the vertical and horizontal widths of the obturator internus tendon were 6.87 ± 1.61 mm and 5.72 ± 1.38 mm, respectively. The mean distances of the anterior and posterior margins of the piriformis tendon insertion from the posterior limit of the greater trochanter, defined as a percentage of the anteroposterior length of the greater trochanter, were 63.3% ± 9.4% and 43.0% ± 9.4%, respectively. Equivalent mean distances for the obturator internus insertion were 73.0% ± 6.6% and 55.9% ± 7.0%, respectively. On the basis of the relationship between the piriformis and obturator internus tendons in terms of the angle and point at which they cross, in addition to any degree of tendon fusion, four classifications were identified. This study shows that the most posterior margins of the piriformis and obturator internus attachments are located more than one-third of the way along the greater trochanter, suggesting that current osteotomies would not include these external rotators in the majority of cases.
在髋关节后入路暴露过程中保留梨状肌可能会降低全髋关节置换术后脱位的发生率。本研究旨在确定梨状肌和闭孔内肌肌腱的解剖变异，以便为髋关节提供保留梨状肌的入路。检查了 15 具尸体（5 名男性和 10 名女性，年龄 65-79 岁）的 29 个近端股骨。记录了肌腱交叉角度、在大转子上的位置和插入方式，以及肌腱在插入前融合的程度。梨状肌肌腱的垂直和水平宽度的平均值（和相关标准差）分别为 4.78 ± 1.31 mm 和 7.35 ± 1.74 mm。闭孔内肌肌腱的垂直和水平宽度的平均值（和相关标准差）分别为 6.87 ± 1.61 mm 和 5.72 ± 1.38 mm。梨状肌肌腱插入后缘与大转子后缘的前后距离（以大转子前后长度的百分比表示）的平均值分别为 63.3% ± 9.4%和 43.0% ± 9.4%。闭孔内肌插入的等效平均值分别为 73.0% ± 6.6%和 55.9% ± 7.0%。根据梨状肌和闭孔内肌肌腱的交叉角度和交叉点之间的关系，以及任何程度的肌腱融合，确定了四种分类。本研究表明，梨状肌和闭孔内肌附着的最靠后缘位于大转子的三分之一以上，这表明在大多数情况下，目前的截骨术不会包括这些外旋肌。
