FIGURE 6-11. Varying presentations of the proximal phalanx shaft. A: Phalangeal ridge (arrowheads, second, third, and fourth toes). B: Increased girth along the anterior aspect of the medial shaft (arrow) simulating a periosteal reaction. Present bilaterally.
FIGURE 6-14. Varying presentations of the first metatarsal head. A: Flat. B: Combined flat/ridge. (For comparison, an example of the round metatarsal head is seen in Figure 6-13B.) C: Prominent lateral tubercle (arrow).
FIGURE 6-15. Varying presentations of the lesser metatarsal heads. A: Enlarged superolateral tubercle (arrowhead), second metatarsal (a bilateral finding). B: Exaggerated notch between superolateral tubercle and anterior articular surface (arrowhead), second metatarsal (a bilateral finding). C: Enlarged and elongated plantar-medial condyle (arrowheads), fourth metatarsal.
FIGURE 6-16. Metatarsal variants of form. A: Increased girth (first metatarsal). B: Decreased girth third metatarsal, increased girth second metatarsal. C: Fifth metatarsal bowing with cortical thickening (arrowheads). A variant of density, radiolucency of the fifth metatarsal head medially, is also seen.
FIGURE 6-17. Varying presentations of the metatarsal base. A: Exaggerated, irregular intermetatarsal surfaces (arrowheads) between bases and proximal shafts (a bilateral finding). B: Articulation between first- and second metatarsal bases (arrowhead) (a bilateral finding). C: Tubercle for tibialis anterior tendon insertion (arrow) (a bilateral finding).
FIGURE 6-10. Short proximal phalanx third and fourth toes (a bilateral finding).
FIGURE 6-11. Varying presentations of the proximal phalanx shaft. A: Phalangeal ridge (arrowheads, second, third, and fourth toes). B: Increased girth along the anterior aspect of the medial shaft (arrow) simulating a periosteal reaction. Present bilaterally.
FIGURE 6-12. Varying presentation of the sesamoids: Smaller tibial sesamoid (bilateral).
FIGURE 6-13. Variation of metatarsal length. A: Normal. B: Short second metatarsal.
FIGURE 6-14. Varying presentations of the first metatarsal head. A: Flat. B: Combined flat/ridge. (For comparison, an example of the round metatarsal head is seen in Figure 6-13B.) C: Prominent lateral tubercle (arrow).
FIGURE 6-15. Varying presentations of the lesser metatarsal heads. A: Enlarged superolateral tubercle (arrowhead), second metatarsal (a bilateral finding). B: Exaggerated notch between superolateral tubercle and anterior articular surface (arrowhead), second metatarsal (a bilateral finding). C: Enlarged and elongated plantar-medial condyle (arrowheads), fourth metatarsal.
FIGURE 6-16. Metatarsal variants of form. A: Increased girth (first metatarsal). B: Decreased girth third metatarsal, increased girth second metatarsal. C: Fifth metatarsal bowing with cortical thickening (arrowheads). A variant of density, radiolucency of the fifth metatarsal head medially, is also seen.
FIGURE 6-17. Varying presentations of the metatarsal base. A: Exaggerated, irregular intermetatarsal surfaces (arrowheads) between bases and proximal shafts (a bilateral finding). B: Articulation between first- and second metatarsal bases (arrowhead) (a bilateral finding). C: Tubercle for tibialis anterior tendon insertion (arrow) (a bilateral finding).
FIGURE 6-18. Tubercle along the medial surface of the medial cuneiform (arrowhead).
FIGURE 6-19. Cuboid variant of form: Ridge separating fourth- and fifth metatarsal articulating surfaces (arrowhead).