Fifth metacarpal bone Fifth metacarpal bone The fifth metacarpal bone (metacarpal bone of the little finger or pinky finger) is the most medial and second-shortest of the metacarpal bones. It presents on its base one facet on its superior surface, which is concavo-convex and articulates with the hamate, and one on its radial side, which articulates with the fourth metacarpal. On its ulnar side is a prominent tubercle for the insertion of the tendon of the extensor carpi ulnaris muscle. The dorsal surface of the body is divided by an oblique ridge, which extends from near the ulnar side of the base to
Bone pain (C fiber) sensory neurons. In combination, they can provide an initial burst of pain, initiated by the faster myelinated fibers, followed by a slower and longer-lasting dull pain initiated by unmyelinated fibers. Nociceptors responsible for bone pain can be activated via several mechanisms including deterioration of surrounding tissue, bone destruction, and physical stress which shears the bone, vascular, muscle, and nervous tissue. Common causes of bone and joint pain in adults, such as osteoarthritis and gouty arthritis are rare in children, as these diseases are a sequelae of chronic wear and tear for several years. The use of anesthetics within