Sesamoid Bone

Sesamoid Bone.

The sesamoid bones are seed-like bony nodules found embedded in the tendons of muscles (in Arabic: Sesame = seed).

Characteristic features

• Develop in tendons of the muscles after birth.
• Are devoid of periosteum.
• Are devoid of Haversian systems.
• Ossify by multiple secondary centres.

“The Role Of Sesamoid Bones In Reducing Tendon Friction”

“Functions Of Sesamoid Bones In The Body”

Functions of bones

• Alter the direction of the pull of the muscle tendon.
• Minimize the friction of the tendon against the bone.
• Modify and sustain pressure.
• Provide an additional articular surface to a joint.
• Protect the tendons from wear and tear.
• Act as pulleys for muscular contraction.

“Importance Of Sesamoid Bones For Movement”

Sites of bones

• Tendon of quadriceps femoris (patella)
• Lateral head of gastrocnemius muscle (fabella)
• Tendon of flexor carpi ulnaris (pisiform)
• Two bony nodules (sesamoid bones) beneath the head of 1st metatarsal in the tendon of flexor pollicis brevis
• Bony nodule in the tendon of adductor hallucis
• Bony nodule in the tendon of peroneus longus where it winds around the cuboid bone