Pharynx & Larynx

1.A 4 year old child swallowed a shirt button. Since the child began to suffocate she was rushed to the hospital, where on x-ray examination, impaction of foreign body in the larynx was confirmed. Based on your knowledge in anatomy, answer the following questions. • Which is the narrowest part of the laryngeal cavity. • Briefly describe the interior of larynx. • Which muscle is known as the safety muscle of the larynx and why. • Name the joints at which the muscles of larynx act and briefly mention the movements taking place at these joints. • What anatomical structures in the midline of neck are encountered during surgical approach to trachea below isthmus of thyroid gland. (1+3½ +1+2½ +2=10)

1.Interior of larynx

1.Naso-pharynx

2.Pharyngeal muscles and their nerve supply

3.Boundaries and clinical significance of pyriform fossa

4.Constrictors of pharynx

5.Features of nasopharynx

6.Cavity of larynx

7.Pharyngeal constrictors

8.Sphincter muscles of the pharynx

1.Vocal cords

2.Name two cartilages of Larynx

3.Two features of lateral wall of nasopharynx

4.Name two unpaired laryngeal cartilages

5.Structures piercing thyrohyoid membrane

6.Piriform recess

1.During thyroidectomy if inferior thyroid artery is ligated very close to the gland which nerve will be injured

• a) Recurrent laryngeal
• b) Superior laryngeal
• c) Internal laryngeal
• d) External laryngeal

2.During thyroidectomy the surgeon will ligate the superior thyroid artery very close to the upper pole of lateral lobe of thyroid gland in order to avoid injury to which nerve

• a) Superior laryngeal
• b) External laryngeal
• c) Internal laryngeal
• d) Hypoglossal

3.If the nerve lying close to superior thyroid artery is cut by mistake which muscle will be paralysed

• a) Thyroarytenoid
• b) Transverse arytenoid
• c) Vocalis
• d) Cricothyroid

4.The thyroid swelling moves on deglutition because suspensory ligament of Berry attaches the thyroid gland to

• a) Hyoid bone
• b) Thyroid cartilage
• c) Cricoid cartilage
• d) Pharynx

5.The following muscle is supplied by the glossopharyngeal nerve

• a) Stylopharyngeus
• b) Palatopharyngeus
• c) Salpingopharyngeus
• d) Superior constrictor