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Boyer diss 2009 1046..

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flush with the shaft distal to it. The proximal end of the capitate facet has a surface area<br />

of 7.1 mm 2 .<br />

The “set 2” MC III, as for MC II’s, is similar to the “set 1” MC III (Figs. 4.15,<br />

16B). It differs in being a larger and more gracile element, and in having an absolutely<br />

and proportionally deeper distal end (Table 4.10). The proximal end also differs in<br />

having its radial side facet flush with, instead of flaring beyond, the shaft distal to it. The<br />

proximal end capitate facet of the “set 2” MC III has a surface area of 8.45 mm 2 .<br />

Metacarpal IV description.—MC IV of set 1 (Figs. 4.14D, 15) is fragmentary and<br />

missing its distal end. The proximal end facet for the hamate, like the carpal facets on<br />

MC II and III, projects farther proximally on its ulnar side. MC IV differs from MC II’s<br />

and is similar to MC III’s in having a proximal end that is mediolaterally wider than the<br />

the shaft just distal to it. However, it is more like the “set 2” MC III in having the radial<br />

side proximal facet flush with the shaft beyond it, while the ulnar side proximal facet is<br />

more flaring. On the other hand, the “set 1” MC IV differs from MC III’s and is actually<br />

similar to the “set 1” MC II in having a carpal facet that faces dorsally relative to its<br />

shaft. The radial side proximal facets match the corresponding ulnar side facets on the<br />

“set 1” MC III perfectly, indicating that the two bones articulated. The ulnar side of the<br />

proximal end of MC IV is concave, unlike those of MC II’s and III’s, which are flat.<br />

Furthermore the ulnar facet is not differentiated as distinctly into dorsal and ventral<br />

regions. The dorsal part of the ulnar side facet is elliptical in outline, similar to the dorsal<br />

proximal facets on other metacarpals, but the ventral extension of this facet is<br />

proximodistally proportionally thicker than in the other metacarpals. Finally, MC IV<br />

312

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