Andermahr Jonas, Jubel Axel, Elsner Andreas, Johann Jan, Prokop Axel, Rehm Klaus Emil, Koebke Juergen
Clinic of Trauma-, Hand- and Reconstructive Surgery, University of Cologne, Köln, Germany.
Clin Anat. 2007 Jan;20(1):48-56. doi: 10.1002/ca.20269.
Intramedullary fixation is used increasingly to treat clavicular fractures. Anatomical variations in the clavicle of relevance to this procedure are analyzed. The length, diameters and curvature of the clavicle were measured in 196 specimens from the dissecting room. The calcium bone density was analyzed in 300 cross-sectional samples of 100 specimens. The thickness of cortical and medullary bone of 70 slices was analyzed from freshly plastinated clavicles with implants in place. The female clavicle was shorter, less curved, and had a lower concentration of calcium than the male clavicle. Measurement of cortical thickness showed a mean value of 1.05 +/- 0.23 mm at the most sternal measuring point, 2.05 +/- 0.29 mm at the midpoint of the clavicle, and 0.95 +/- 0.35 mm at the acromial end. The thinnest regions were the medial ventral cortex and the dorsal acromial cortex. These measurements explain clinical observations on nail perforation. The diameter of the medullary canal measured 6.7 +/- 2.6 mm at its narrowest part, so that reaming (i.e., predrilling the medullary canal) prior to 3.5 mm titanium nail insertion is not necessary. The main difficulties encountered when placing a nail are secondary to the S-curvature of the clavicle. In 80% of fractures, the break is located at the narrowest diameter of the medullary canal. Thus, the clavicle displays definite gender- and side-specific anatomical features in terms of length, diameter, curvature, and calcium concentration. These should be considered when performing intramedullary fixation.
髓内固定越来越多地用于治疗锁骨骨折。本文分析了与该手术相关的锁骨解剖变异情况。在解剖室的196个标本上测量了锁骨的长度、直径和曲率。对100个标本的300个横断面样本进行了钙骨密度分析。从带有植入物的新鲜塑化锁骨上分析了70个切片的皮质骨和髓质骨厚度。女性锁骨比男性锁骨短、弯曲度小且钙浓度低。皮质厚度测量显示，在最靠近胸骨的测量点平均值为1.05±0.23毫米，在锁骨中点为2.05±0.29毫米，在肩峰端为0.95±0.35毫米。最薄的区域是内侧腹侧皮质和肩峰背侧皮质。这些测量结果解释了临床上关于髓内钉穿孔的观察情况。髓腔最窄处直径为6.7±2.6毫米，因此在插入3.5毫米钛钉之前无需扩髓（即预先钻髓腔）。置入髓内钉时遇到的主要困难源于锁骨的S形弯曲。在80%的骨折中，骨折部位位于髓腔最窄直径处。因此，锁骨在长度、直径、曲率和钙浓度方面表现出明确的性别和侧别特异性解剖特征。在进行髓内固定时应考虑这些因素。
