| 1
.
| Upper pointer: Insertion of extensor expansion into base of terminal phalanx Lower pointer: Collateral parts of extensor expansion (the lumbrical and interosseous muscles insert into these proximally (3) and the collateral parts of the tendon of the common extensor digitorum insert into these dorsally opposite the proximal interphalangeal joint) |
| 2
.
| Central part of tendon of common extensor digitorum muscle (upper pointer indicates insertion on base of middle phalanx) |
| 3
.
| Extensor expansion (insertion of lumbrical and interosseous muscles) |
| 4
.
| Position of metacarpophalangeal joint (covered by transverse fibers of extensor expansion) |
| 5
.
| Junctural tendon |
| 6
.
| Abductor digiti minimi muscle |
| 7
.
| Dorsal interosseous muscles II-V |
| 8
.
| Extensor digiti minimi proper muscle (tendon of insertion) |
| 9
.
| Body of nail |
| 10
.
| Root of nail |
| 11
.
| Lunula of nail |
| 12
.
| Vallum of nail |
| 13
.
| Position of distal interphalangeal joint |
| 14
.
| Position of proximal interphalangeal joint |
| 15
.
| Ligament of digital sheath |
| 16
.
| Extensor expansion of thumb |
| 17
.
| Adductor pollicis muscle (insertion) |
| 18
.
| Dorsal interosseous muscle I |
| 19
.
| Extensor pollicis longus muscle (tendon of insertion) |
| 20
.
| Extensor indicis muscle (tendon of insertion) |
| 21
.
| Common extensor digitorum muscle (tendons of insertion) |
