Abstract：
The plantaris is a short, small muscle that usually originates at the popliteal surface of the femur and has a long, thin tendon that typically inserts into the calcaneal tuberosity. Its role and degree of development have been objects of debate for years. Some authors consider it a vestigial muscle while others believe it is a process of its development. The clinical significance of plantaris muscle is usually related to its morphological variation, which is common and well described in the literature. These variations are often a risk factor for many ailments and disorders. We would like to present another, very rare case of three-headed plantaris muscle (fused with distal Kaplan fibers), and consider what clinical implications it may have.
摘要：
足底很短，小肌肉，通常起源于股骨的pop骨表面，通常插入跟骨结节的薄肌腱。它的作用和发展程度多年来一直是辩论的对象。一些作者认为它是一种残留的肌肉，而另一些作者认为它是它的发展过程。pi肌的临床意义通常与其形态变异有关，这在文献中很常见，也有很好的描述。这些变化通常是许多疾病和病症的风险因素。我们想介绍另一个，非常罕见的三头pi肌（与远端Kaplan纤维融合），并考虑它可能有什么临床意义。
