Dorsal Reinforcement of the MCP Joint
1. Extensor hood – flat layer of fibers that are perpendicular and oblique to the bone and sweep around to the edges of the volar plate
2. Sagittal bands are the fibers on the sides of the extensor hood and they help centralize the extensor tendon – they originate on the palmar plate and insert on the extensor mechanism
3. Natatory Ligament (superficial transverse metacarpal ligament) functions to resist abduction
4. Deep transverse metacarpal ligament functions to prevent the metacarpal heads from splaying apart or abduction.
Key to Extensor Hood Above
A = Terminal tendon
B = Triangular ligament
C = Lateral band
D = Sagittal band
E = Lumbrical muscle
F = Extensor tendon (long)
G = Interosseous muscle
FUN MNEMONIC:
Terminal Tendon…………………………………………………. Totally
Trigangular Ligament…………………………………………… Terrific
Lateral Band………………………………………………………. Lawyers
Sagittal Band…………………………………………………….. Slapped
Lumbrical………………………………………………………….. Lawsuits (to)
Extensor Tendon (long)………………………………………. Everyone
Interosseous Muscle………………………………………….. Inconsiderately
