(634.17) Abnormal Relationship with the Styloglossus and Medial Pterygoid Muscles: A Description of Two Cases

Poster Board Number: C92
Introduction: AAA has separate poster presentation times for odd and even posters.
Odd poster #s – 10:15 am – 11:15 am
Even poster #s – 11:15 am – 12:15 pm

Pil-Woo Kim (Indiana Wesleyan University)

Introduction

Lateral pharyngeal space is of great interest to dentists and surgeons. The pre-styloid space is located in a portion of the lateral pharyngeal space. The pre-styloid space has stylohyoid muscle, styloglossus muscle, stylopharyngeus muscle, and external carotid artery. Medial and lateral pterygoid muscles are located anterior to the pre-styloid space. This study describes the relationship of the structures in the cases.

Hypothesis

The muscular attachment from the medial pterygoid muscle to the styloglossus muscle is unique. Morphological understanding with the external carotid artery of the cases will be helpful to prevent surgical mistakes.

Methods

The two cadavers were found to have a rare medial pterygoid and styloglossus during the dissection in 2020. It had been assessed in the adjacent structures.

Results

Both cases showed that the medial pterygoid muscle has a tendinous attachment from the inside to the styloglossus muscle. The first case’s tendon and muscle were 5mm wide, 3mm thick, and 10mm long and attached to 15mm proximal area of the styloglossus muscle (Fig. 1). The second case’s tendon was 5mm wide, 1mm thick, and 7mm long and attached to a 12mm proximal area of the styloglossus muscle (Fig. 2). Both styloglossus muscles were attached to the tip of the styloid process. Both styloid processes were more than 25mm long from the temporal bone (Fig. 2).

Both external carotid arteries passed through between stylohyoid and styloglossus muscles and ran behind the tendon and up to the head of the mandible (Fig. 1.C).

Conclusion

The medial pterygoid muscle attaches to the ramus of the mandible. The ramus has an accessory fascicle that attaches to the styloglossus muscle in the fetus. It may not entirely disappear after being born. The length of the styloid process may be a contributing factor in the development of eagle syndrome.    

The styloglossus muscle plays an essential role in swallowing, mastication, and speech. The attachment involves the function of the motion of the mandible. The external carotid artery travels along with the accessory muscle-tendon and needs to be considered during surgery.





Figure 1; Figure 2