The dorsal branch situated at the deep of ulnar nerve and ascending along the ulnar groove, and divided into 4~ 8 periosteal braches to the medial upper part of ulna with a diameter of 0.3~ 1.0 mm. 背侧支位于尺神经深面,沿尺神经沟上行,沿途分出4~8支外径在0.3~1.0mm的骨膜支,分布尺骨上段内侧骨面。
The trophozoite has four pairs of flagella emerging from the dorsal marginal groove. 滋养体有4对鞭毛,均由背侧边缘沟伸出体外。