free nerve ending

1. The free nerve endings was distributed in the normal and osteoarthritis of the knee joint synovium, the distributions of the free nerve ending concentrated in the synovium of osteoarthritis, it may be the cause of the pain. 2.
   结论：1.游离神经末梢在正常关节与骨关节炎关节滑膜中均有分布，骨关节炎组的分布密集，可能是其疼痛的原因。

noun

1. microscopic sensory nerve endings in the skin that are not connected to any specific sensory receptor