Two Cases of Enlarged Zuckerkandl's Tubercle of the Thyroid Displacing the Recurrent Laryngeal Nerve Laterally.

The thyroid has many anatomic variations. Zuckerkandl's tubercle (ZT) is the posterior extension of lateral lobes. ZT has a relation with the recurrent laryngeal nerve (RLN). RLN lateral to ZT is an uncommon occurrence. This paper presents two cases of this uncommon situation. A 60-year-old female patient with large multinodular goiter was treated with total thyroidectomy. A 69-year-old male patient with follicular neoplasm was treated with total lobectomy. The inferior thyroid arteries and the recurrent laryngeal nerves were identified with usual lateral approach. A left ZT was found in case 1 and a right ZT in case 2. Distal parts of the RLNs were displaced laterally by enlarged ZTs in both cases. Grade 3 ZTs composed of thyroid tissue were placed between the trachea and the RLNs. The ZT is a common anatomic feature of the thyroid. Close relation of the tubercle with the RLN is an important surgical entity. The enlarged ZT seldom pushes the nerve laterally. The knowledge of the anatomy of ZT and its relation with the RLN including all variations is mandatory for safe thyroid operations.