PTH and osteoarthritis: We have previously shown that Netrin-1, secreted by osteoclasts, acts as a key nerve axon attractant factor, increasing nociceptive sensory innervation to the affected regions as observed in models of osteoarthritis and LBP.13,28 This study highlights that the nerve repellant factor, Slit3, is increased in response to PTH, counteracting the overactivity of osteoclasts and facilitating sensory denervation to mitigate LBP.