The role of selective versus routine parathyroid auto transplantation during total thyroidectomy in reducing rate of permanent hypoparathyroidism

Thyroidectomy, though a common procedure performed world over, can result in life changing

complications such as post-operative hypoparathyroidism and recurrent laryngeal nerve palsy.

Post-operative hypoparathyroidism is the most commonly encountered complication and is

defined as a low (below the lower limit of the labs reference range) intact PTH (parathormone)

level, following bilateral thyroid surgery.

This may be either temporary when it resolves within six months of surgery or permanent when

PTH levels persist to be low six months after surgery. The reported incidence of temporary and

permanent hypoparathyroidism is 18-39% and 0-3% respectively. The reasons for the

development of post-thyroidectomy hypoparathyroidism are multifactorial, however, the most

important cause is related to the parathyroid glands and may result from either inadvertent

injury/resection to the parathyroid gland during thyroidectomy or due to devascularization of

parathyroid glands.

The management of temporary hypoparathyroidism include oral calcium and activated vitamin

D supplementation and intravenous calcium infusion in a subset of patients. This results in

increased hospital stay and cost. Further, there is a risk of re-admissions for the management of

severe hypoparathyroidism. Permanent hypoparathyroidism on the other hand, even though less

frequent, significantly impairs quality of life. In addition, long term effects include chronic renal impairment, reduced bone remodeling, increased psychiatric complaints and basal ganglia

calcification.

Various adjuncts to aid identification and the assessment of viability of the parathyroid glands

during thyroid surgery, in order to decrease the rates of post-surgery hypoparathyroidism, have

been developed. These include parathyroid angiography with indocyanine green, parathyroid

auto fluorescence, carbon nanoparticles and gamma probe. Though these methods have

reported some benefit in decreasing temporary hypoparathyroidism rates, its effects on

permanent hypoparathyroidism have not been promising. In addition, these methods are time

consuming and expensive. A simple, inexpensive, easy alternative to the above is parathyroid

gland auto-transplantation. This involves the reimplantation of at least one parathyroid gland

during thyroid surgery into the sternocleidomastoid muscle. Reimplanted parathyroid glands

have been shown to regain function in 6-8 weeks following transplant. There are two methods

of parathyroid auto-transplantation: routine and selective. We aim to compare these two

methods to determine if there is a significant