Brief Intraoperative Electrical Stimulation for Prevention of Shoulder Dysfunction After Oncologic Neck Dissection

Brief Intraoperative Electrical Stimulation for Prevention of Shoulder Dysfunction After Oncologic Neck Dissection (ESSAN): a Double-blinded, Randomized Control Trial

Introduction: Shoulder pain and dysfunction is common after oncologic neck dissection for head and neck cancer (HNC). These symptoms can hinder postoperative rehabilitation and oral hygiene, activities of daily living (ADLs), and return to work after treatment. Due to the rising incidence of Human papillomavirus (HPV)-associated oropharyngeal cancer, patients are often diagnosed in the 3rd or 4th decade of life, leaving many potential working years lost. Brief electrical stimulation (BES) is a novel technique that has been shown to enhance neuronal regeneration after injury through a brain-derived neurotrophic growth factor (BDNF)-driven molecular pathway. The aim of this study is to examine the utility of intraoperative BES in prevention of shoulder pain and dysfunction after oncologic neck dissection.

Methods: All adult patients with a new diagnosis of HNC undergoing surgery with neck dissection including Level IIb and postoperative radiotherapy will be enrolled. Patients will undergo intraoperative BES after completion of neck dissection for 60 minutes continuously at 20 Hz with an intensity of 1.5 times the motor threshold. Postoperatively, patients will be evaluated using the Constant-Murley Shoulder Score, a scale that assesses shoulder pain, activities of daily living (ADLs), strength, and range of motion. Secondary outcomes measured will include scores on the Oxford Shoulder Score, the Neck Dissection Impairment Index (NDII), and the University of Washington Quality of Life (UW-QOL) score. Primary and secondary outcomes will be assessed at 1, 2, 3, 6, and 12 months postoperatively. Study and placebo groups will be compared using a Mann-Whitney analysis.

This study will be conducted as a randomized, double-blinded, placebo-controlled trial. Two parallel treatment groups will be examined with a 1:1 allocation: 1) brief intraoperative electrical stimulation continuously at 20 Hz at an intensity of 1.5 times the motor threshold for 60 minutes, or 2) sham/no stimulation for 60 minutes. Individuals will be allocated to treatment groups using a block randomization sequence. Participants and researchers measuring outcomes will be blinded to treatment groups. Stimulation (BES or sham) will occur intraoperatively immediately following neck dissection for 60 minutes.

Inclusion Criteria:

• Age 18-55 years
• New adult head and neck cancer patients
• Undergoing major resection and reconstruction surgery including oncologic neck dissection including Level IIb
• Undergoing adjuvant therapy

Exclusion Criteria:

• Oncologic resection necessitating unilateral or bilateral resection of the sternocleidomastoid, SAN, partial resection of trapezius muscle, hypoglossal nerve, skin, carotid resection, or deep muscle resection
• Previous surgery or radiation therapy to the head and/or neck
• Recurrent head and neck cancer
• Preoperative, pre-existing shoulder dysfunction or weakness, including myopathy, neuropathy, or arthropathy
• Presence of existing implanted electrical device (eg. pacemaker, deep brain stimulator, vagal nerve stimulator
• Previous or current neurological disease which may adversely affect shoulder dysfunction
• Unable to read, write, and speak English
• Lacking capacity to give consent
• Unwilling to present for follow-up appointments or follow-up objective shoulder assessment