Volume 39, Issue 2, 2023

Chronic post-amputation pain (CPAP), including stump pain and phantom pain, causes great suffering to amputees, but the mechanism is still elusive. Pu et al. found that the stump neuroma plays an essential role in CPAP. Specifically, the nociceptors express the mechanosensitive ion channel TMEM63A and macrophages infiltrate into the dorsal root ganglia then work synergistically to promote CPAP. In the cover image, two post-amputation mice are standing on the Tai Chi diagram composed of Yin and Yang. The mouse standing on the Yin has more TMEM63A channels and macrophage infiltration is experiencing pain and weeping, while the mouse standing on the Yang has fewer TMEM63A channels and macrophages is free of pain and dancing happily. See pages 177–193. (Cover designed by Drs Shaofeng Pu and Fan Li).