Calcaneal spur is an inflammatory condition of the heel. Specifically, it is anexostosis, which is a benign neoformation of bone tissue that develops in the heel area.
The occurrence of calcaneal spur is related to chronic disease, such asarthrosis of the foot or ankle, plantar fasciitis, and inflammation of the Achilles tendon insertion on the heel(enthesopathy). Very slowly, these disorders predispose to the formation of calcium salt deposits and a bony protuberance (i.e., the actual calcaneal spur); in turn, the presence of exostosis in the calcaneus correlates with a painful inflammatory state.