The skeletal derivatives of the second branchial arch, also known as the hyoid arch, contribute to the formation of several important structures in the head and neck. Here are some of the skeletal derivatives associated with the second branchial arch:
- Stapes: The stapes is one of the three ossicles of the middle ear, along with the malleus and incus. It forms from the dorsal end of the second branchial arch cartilage. The stapes plays a crucial role in transmitting sound vibrations from the tympanic membrane to the inner ear.
- Styloid Process of Temporal Bone: The styloid process is a slender, pointed projection of bone located inferior to the temporal bone. It serves as an attachment site for several muscles, ligaments, and tendons in the neck. The styloid process develops from the proximal part of the second branchial arch cartilage.
- Lesser Horn and Upper Part of the Body of Hyoid Bone: The hyoid bone is a horseshoe-shaped bone located in the anterior neck region. It does not articulate directly with any other bones but is suspended by ligaments and muscles. The lesser horn and upper part of the body of the hyoid bone develop from the proximal portion of the second branchial arch cartilage.
These skeletal derivatives of the second branchial arch contribute to the formation of critical structures involved in hearing, speech, swallowing, and neck muscle attachment. Understanding the embryological origin of these structures helps in comprehending their functional and clinical significance in the head and neck region.