Body Of The Humerus, Posterior View

Description

Humeral shaft anatomy dominates this posterior view, with the spiral (radial) groove crossing the mid-diaphysis on an oblique inferolateral course. Proximally, the posterior surface is broader and smoother, while the distal third tapers toward the supracondylar region; the medial and lateral borders become more defined as they descend. Lateral to the groove, the posterior contour corresponds to the lateral aspect of the shaft, whereas the medial side remains flatter, reflecting the transition toward the medial supracondylar ridge. Radial groove topography matters because the radial nerve and the profunda brachii (deep brachial) artery lie in close apposition to this bony channel before the nerve pierces the lateral intermuscular septum. Mid-shaft fractures at this level, including the classic Holstein-Lewis pattern in the distal third, can produce radial neuropraxia with wrist and finger extensor weakness, and operative fixation demands careful awareness of where the nerve hugs bone. Surface relief and the shallow, slanted geometry of the groove help you orient the posterior diaphysis without relying on proximal articular landmarks. A high-risk corridor. Use this illustration for upper limb osteology labs, for fracture-mechanics figures in orthopedic texts, or for preoperative teaching materials that map the radial nerve’s relationship to the posterior humeral cortex during posterior or lateral approaches to the shaft. Anatomical accuracy verified by SciePro's Medical Advisory Board.