The Tubercle of Zuckerkandl : An Important Landmark Revisited

Abstract

To study the incidence of the tubercle of Zuckerkandl (ZT) among Indian patients subjected to thyroid surgery at a tertiary care cancer centre and its relevance in localization of recurrent laryngeal nerve (RLN). Prospective study on 144 patients (48 males, 96 females) undergoing thyroidectomy (35 hemithyroidectomies, 109 total thyroidectomies) from September 1st 2010 - February 28th 2013. 144 specimen/253 lobes (129 right, 124 left) were evaluated. Findings were recorded by the same team to ensure consistency. Presence, shape, grade (Pelizzo's) of ZT and relationship to RLN were documented. ZT was identified in 90.5 % (n = 229), commoner on the right (n = 120) than on left (n = 109). ZT was Grade 0 in 9.5 %, Grade I in 28.9 %, Grade II in 50.5 % and Grade III in 11 % of cases. In all patients ZT was unilobed. Recurrent laryngeal nerve (RLN) was consistent in position and was posterior to ZT in all cases. There were no branches of the RLN above the ZT. The ZT is a useful guide in locating RLN. Surgeon should be aware about the incidence, shape, grade and relation to RLN which is different in the Indian population as compared to what has been reported globally.

Thyroid Tubercle of Zuckerkandl May Not Arise from the Ultimobranchial Body: Results from Histological Analysis

“…The TZ is the posterior extension of the thyroid lateral lobes or a protuberance from the posterolateral border of the thyroid lobe [1-8]. It is significantly more common in the right than in the left lobe [5, 7, 8, 11-13]. It is usually observed in the middle third of the thyroid lateral lobe (80–85%) and it can also be found in the lower part or in the upper third of the lobe [1].…”

“…Pelizzo et al [4] classified TZs into four grades based on size: grade 0, unrecognizable; grade 1, only a thickening of the lateral edge; grade 2, <1 cm; and grade 3, ≥1 cm. Previous studies have shown that grade 2 TZs seem to be the most common, although their frequency in different studies varied [3, 4, 7, 13], likely because it is unclear whether “size” indicates the length of the base or the height of the structure. In addition, TZs differ in shape or size depending on whether they are fresh or fixed [7].…”

“…In addition, TZs differ in shape or size depending on whether they are fresh or fixed [7]. The TZ is present in 60–83% of the patients undergoing thyroidectomy [1, 2, 5, 8, 10-13]. In this study, however, only 2.9% of the thyroidectomy cases were included.…”

“…It was first described in 1902 by the Viennese anatomist Emil Zuckerkandl as “Processus posterior glandulae thyroideae” [9]. The TZ is present in 60–83% of the patients undergoing thyroidectomy [1, 2, 5, 8, 10-13] and is mostly located in the mid-third of the thyroid lobe [1]. It is an important landmark for the identification of the recurrent laryngeal nerve during thyroid surgery because most recurrent laryngeal nerves pass beneath the TZ [1, 2, 5, 14].…”

“…The paired smaller lateral anlagen arise from the ultimobranchial body (UB) and attach to the posterior surface of the thyroid during the fifth week [19, 20]. The remnants of the UB, when present, are thought to persist as the TZ [5, 11, 13, 15].…”