Anatomy of the karate chop.
A reticular shell of tendon-like fibers lines the teguments of the hypothenar space. This fibrous shell, together with the exceptionally thick skin and the arrangements of the fat tissues, gives the "heel of the hand" a remarkable resistance to pressure.
D001696:Biomechanical Phenomena; D006225:Hand / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans