Background:

Quadriceps tendon (QT) autografts with and without a bone block are the least studied and least used options for anterior cruciate ligament reconstruction surgery. In particular, there is a lack of literature describing patellar anatomy. Until now, guidelines for patellar bone block harvesting have been based solely on personal experience. In this study, we intended to derive recommendations from physical regularities and objective criteria.

Purpose:

To determine the maximal, individual-related length and depth of the bone block that can be safely harvested and to provide guidelines to help surgeons make decisions on graft choice.

Study Design:

Descriptive laboratory study.

Methods:

The study group consisted of 50 male participants and 50 female participants (mean age, 29.4 ± 7.9 years) who underwent 3.0-T magnetic resonance imaging of their knee. Patellar height was determined at the center of the middle third of the QT insertion on the patella and the medial and lateral endpoints; the depth was measured at the midpoints of the respective heights.

Results:

The mean width of the QT and the mean thickness were 49.0 ± 7.6 and 7.3 ± 1.0 mm, respectively. The mean patellar thickness in reference to the medial endpoint, the center, and the lateral endpoint was 18.3 ± 2.4, 17.9 ± 2.3, and 15.1 ± 2.3 mm, respectively, whereas the mean patellar height was 35.1 ± 4.1, 36.7 ± 4.2, and 35.1 ± 3.9 mm. In general, the tendon and patellar dimensions were significantly larger in male participants than in female participants (P = .016).

Conclusion:

Bone block harvesting, with its depth not exceeding 50% of the patellar thickness and its length accounting for <50% of the patellar height, poses the least risk for a patellar fracture when located medial to midline. If the bone block is excised from the medial half of the central area (the latter is defined by the middle third of the QT insertion), with the outer edge of the saw positioned at the medial border of the central area, a graft of 15 mm length, 10 mm width, and 8 mm depth can be safely harvested in all White male participants and almost all female participants taller than 165 cm, according to our findings.

Clinical Relevance:

This is the first study presenting recommendations for patellar bone block harvesting at the quadriceps tendon insertionbased on physical regularities and objective criteria and not on personal experience.

中文翻译：

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股四头肌腱-骨块采集部位的髌骨尺寸变化：一项磁共振成像研究，用于评估采集足够骨块的安全区

背景：

带和不带骨块的股四头肌腱 (QT) 自体移植物是前交叉韧带重建手术研究最少和使用最少的选择。特别是缺乏描述髌骨解剖的文献。到目前为止，髌骨块采集指南完全基于个人经验。在这项研究中，我们打算从物理规律和客观标准中得出建议。

目的：

确定可以安全采集的骨块的最大、个体相关的长度和深度，并提供指导以帮助外科医生做出移植物选择的决定。

学习规划：

描述性实验室研究。

方法：

该研究组由 50 名男性参与者和 50 名女性参与者（平均年龄 29.4 ± 7.9 岁）组成，他们接受了膝关节 3.0-T 磁共振成像。髌骨高度在髌骨上 QT 插入的中间三分之一的中心以及内侧和外侧端点处确定；深度是在各个高度的中点测量的。

结果：

QT 的平均宽度和平均厚度分别为 49.0 ± 7.6 和 7.3 ± 1.0 mm。参考内侧终点、中心和外侧终点的平均髌骨厚度分别为 18.3 ± 2.4、17.9 ± 2.3 和 15.1 ± 2.3 mm，而平均髌骨高度为 35.1 ± 4.1、36.7 ± 4.2 和35.1 ± 3.9 毫米。一般来说，男性参与者的肌腱和髌骨尺寸明显大于女性参与者（P = .016）。

结论：

骨块取骨深度不超过髌骨厚度的 50%，长度小于髌骨高度的 50%，位于中线内侧时发生髌骨骨折的风险最小。如果骨块从中央区域的内侧一半（后者由 QT 插入的中间三分之一定义）切除，锯的外边缘位于中央区域的内侧边缘，则移植 15根据我们的研究结果，所有白人男性参与者和几乎所有身高超过 165 厘米的女性参与者都可以安全地收获毫米长、10 毫米宽和 8 毫米深。

临床相关性：

这是第一项基于身体规律和客观标准而非个人经验提出在股四头肌腱插入处截取髌骨块的建议的研究。