Incidence and importance of the tubercle of Zuckerkandl in thyroid surgery.

OBJECTIVE: To define the incidence of a distinct tubercle of Zuckerkandl (TZ) and confirm its anatomical relationships with the recurrent laryngeal nerve and the superior parathyroid gland.

DESIGN: Two prospective series.

SETTING: University teaching hospital, Australia.

SUBJECTS: 200 patients who required thyroidectomy.

INTERVENTIONS: Anatomical and clinical observations in two series of patients (n = 100 in each). The first defined the incidence of a TZ and preoperative symptoms; the second delineated the relationship of the TZ to the recurrent laryngeal nerve and the superior parathyroid gland.

MAIN OUTCOME MEASURES: Anatomical relationships.

RESULTS: A TZ was identified in 63% of patients and was > 1 cm in 45%. In 93% of patients with an enlarged TZ, the recurrent laryngeal nerve lay medial to it and the nerve was found lateral to the TZ in 7% of cases. The superior parathyroid gland was usually cranial to the TZ and posterior to the recurrent laryngeal nerve. The size and position of the TZ did not correlate clearly with symptoms.

CONCLUSIONS: The TZ is a distinct feature of the thyroid gland that can be recognised during most thyroidectomies. The size and the position of the TZ have no constant relationship to preoperative symptoms. An understanding of the consistent anatomical relationship between the TZ and recurrent laryngeal nerve and superior parathyroid gland is crucial for safe thyroidectomy.