Evaluation of the Simultaneous Use of Topical Methylprednisolone and Topical Bupivacaine in the Retropharyngeal Space on the Incidence of Dysphagia Following Anterior Cervical Discectomy and Fusion (ACDF): A Single-Blind Clinical Trial

To determine the effect of simultaneous topical methylprednisolone and topical bupivacaine administration in the retropharyngeal space on the incidence of dysphagia after ACDF

A phase 3 single-blind controlled clinical trial will be conducted on 60 patients. All patients who meet the inclusion criteria will be assigned to either the intervention or control group using a block randomization approach, with the randomization sequence generated through the website https://www.sealedenvelope.com/simple-randomiser/v1/lists. Accordingly, in the intervention group of 30 patients, a combination of 1 cc (40 mg) methylprednisolone and 10 cc (50 mg) of 0.5% bupivacaine will be administered into the retropharyngeal space after irrigation and before fascial closure.

Patients who are candidates for anterior cervical discectomy and fusion surgery at Shariati Hospital in Tehran will be enrolled and allocated to either the intervention or the control group. The patients will be blinded to their group assignment. Patients in the intervention group will receive an injection of the designated compound into the retropharyngeal space, whereas patients in the control group will not receive the injection

Inclusion criteria: Patients undergoing ACDF (up to 3 levels) between C2 and C7. Exclusion criteria: Age <18 or >65 years, oropharyngeal tumors, neurological or psychiatric disorders, acute cervical trauma, substance abuse, prior anterior cervical surgery, and pregnancy.

In patients undergoing ACDF surgery, the intervention group will receive a local application of a combination of methylprednisolone and bupivacaine in the retrpharyngeal space, while the control group will not receive this combination.

Postoperative dysphagia severity, postoperative odynophagia severity, and duration of surgery

Participants who met the inclusion criteria and provided informed consent were randomly allocated to either the intervention or control group. Randomization was performed using block randomization with a 1:1 allocation ratio, and the unit of randomization was the individual patient. The random allocation sequence was generated using a computer-based random number generator through the website https://www.sealedenvelope.com/simple-randomiser/v1/lists. Accordingly, a total of 60 patients were randomly assigned to two equal groups of 30 patients each. To minimize allocation bias, the pre-generated random sequence was applied sequentially at the time of patient enrollment. In this study, only the patients were blinded to group allocation (single-blind), while the surgeon and the investigator were aware of the assigned intervention.

Participants are informed that they will be randomly assigned to one of the two groups.

The participants' data file will remain exclusively with the researcher for future analyses; however, the results obtained from the statistical data will be fully shared with all researchers in the form of a published article.