The Base Of The Metacarpal Bone In Anterior View

Description

Metacarpal base (basis ossis metacarpi) fills the frame in anterior (palmar) view, emphasizing the proximal, widened end that articulates with the distal carpal row at the carpometacarpal (CMC) joint. The articular surface sits proximally, while the shaft narrows distally and continues toward the metacarpal body, with the palmar cortex and subtle contouring for ligament attachment visible on the anterior aspect. Medial and lateral margins of the base suggest where intermetacarpal articular facets and capsular reflections lie relative to adjacent metacarpals, even when only a single bone is isolated. Orientation is fixed: proximal is superior toward the carpal interface, distal is inferior toward the palm and digits. CMC anatomy is where hand mechanics and pathology meet. The proximal articular region shown here corresponds to common injury patterns at the metacarpal bases, including fracture and fracture-dislocation at the CMC joints after axial load through the palm, and, for the first metacarpal in particular, Bennett and Rolando fracture patterns at the trapeziometacarpal joint that destabilize the base through the pull of abductor pollicis longus. Arthritis also concentrates at these joint surfaces, most famously at the first CMC (trapezium to first metacarpal) but also at the ulnar CMC joints (hamate to fourth and fifth metacarpals), so the clean palmar perspective helps communicate where articular cartilage, capsule, and volar CMC ligaments relate to the bony margins surgeons palpate and protect. Small surfaces matter here. Millimeters decide congruity. Use this illustration in upper limb gross anatomy teaching, hand therapy coursework, orthopedic and plastic surgery publishing, and patient-facing CMC arthritis or metacarpal base fracture education where a palmar landmark-focused view supports correlation with physical exam and standard radiographs. Anatomical accuracy verified by SciePro's Medical Advisory Board.