Enhancing morphological understanding of the lateral pterygoid muscle for orofacial pain treatment: a cadaveric study

Year 2024, , 664 - 669, 27.10.2024

Burcu Candan , Niymet Pelin Çavdar Yılmaz , Ayhan Cömert

https://doi.org/10.32322/jhsm.1510092

Abstract

Aims: Injections to the lateral pterygoid muscle (LPM) have gained popularity for managing orofacial pain. Techniques like ultrasonography (USG), electromyography (EMG), and arthroscopy help prevent improper injections and tissue trauma during the procedure, but they require practitioner expertise and experience. Arthroscopy, while precise, is invasive. Blind injections are simpler and convenient for outpatient settings, but their safety is debated. This study examines the anatomical traits of the area of the injection to contribute to the safety and efficacy of these injections for temporomandibular-related orofacial pain.
Methods: The LPM consistently displayed two distinct bellies-superior and inferior-in 16 dissections of 8 cadavers. We measured lateral pterygoid plate (LPP) depth and length, pterygomaxillary angle, superior and inferior head vertical length, superior and inferior head thickness, distance between zygomatic arch and mandibular notch, and distance between superior border of inferior head and mandibular notch.
Results: Significant correlations were found between distances, thicknesses, and lengths of the muscle heads, indicating critical anatomical relationships relevant for safe injections. The mean age of cadavers was found as 79.00±1.78 years (In this article, the ‘±’ notation corresponds to the standard deviation). The average depth and length of the LPP were 43.47±3.34 mm and 15.61±1.09 mm, respectively. The distance from the zygomatic arch to the mandibular notch was 10.76±0.39 mm, whereas the distance from the superior border of the inferior head to the mandibular notch was 6.74±0.29 mm. Significant associations were found between the distance from the zygomatic arch to the mandibular notch and both the thickness and length of the superior head (p=0.011 and p=0.005). Correlations were also observed between the distance from the superior border of the inferior head to the mandibular notch and the thickness of both heads (p<0.001 and p=0.045).
Conclusion: A greater distance from the zygomatic arch to the mandibular notch, as well as from the superior border of the inferior head to the mandibular notch, may potentially improve the safety and ease of injections into the LPM. Our study, therefore, provides insights to the anatomical traits of the region and contributes to safety of blind LPM injections to treat temporomandibular-related orofacial pain.

Keywords

Lateral pterygoid muscle, orofacial pain, temporomandibular joint, temporomandibular pain, cadaveric study

Ethical Statement

Conducting scientific studies on cadavers or cadaveric body parts do not require ethical approval. The authors would like to express their sincere gratitude to the donors and their families for their contribution to education and science.

References

• Rathee M, Jain P. Anatomy, Head and Neck, Lateral Pterygoid Muscle. [Updated 2022 Oct 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK549799/
• Bhutada MK, Phanachet I, Whittle T, Peck CC, Murray GM. Activity of superior head of human lateral pterygoid increases with increases in contralateral and protrusive jaw displacement. Eur J Oral Sci. 2007;115(4):257-264. doi:10.1111/j.1600-0722.2007. 00461.x
• Jivnani HM, Tripathi S, Shanker R, Singh BP, Agrawal KK, Singhal, R. A study to determine the prevalence of temporomandibular disorders in a young adult population and its association with psychological and functional occlusal parameters. J Prosthodont. 2019;28(1):e445-e449. doi:10.1111/jopr.12704
• Murray GM, Bhutada M, Peck CC, Phanachet I, Sae-Lee D, Whittle T. The human lateral pterygoid muscle. Arch Oral Biology. 2007;52(4):377-380. doi:10.1016/j.archoralbio.2006.10.002
• Rodríguez-Gimillo P, Valverde-Navarro A, Margaix-Muñoz M, Poveda-Roda R, Delgado-Navarro C, Puig-Bernabeu J. Lateral pterygoid muscle ultrasound-guided injection: a technical note. J Stomatol Oral Maxillofac Surg. 2023:101547. doi:10.1016/j.jormas.2023.101547
• Fu KY, Chen HM, Sun ZP, Zhang ZK, Ma XC. Long-term efficacy of botulinum toxin type A for the treatment of habitual dislocation of the temporomandibular joint. Br J Oral Maxillofac Surg. 2010;48(4):281-284. doi:10.1016/j.bjoms.2009.07.014
• Sato F, Kino K, Sugisaki M, et al. Teeth contacting habit as a contributing factor to chronic pain in patients with temporomandibular disorders. J Med Dent Sci. 2006;53(2):103-109.
• Salame TH, Peck CC, Murray GM. A new method for lateral pterygoid electromyographic electrode placement. J Prosthet Dent. 2007;98(3):224-231. doi:10.1016/S0022-3913(07)60059-6
• Borghol K, Abdelrahman A, Pigadas N. Guided botulinum toxin injection to the lateral pterygoid muscles for recurrent dislocation of the temporomandibular joint. Br J Oral Maxillofac Surg. 2021;59(7):845-846. doi:10.1016/j.bjoms.2020.09.036
• Pons M, Meyer C, Euvrard E, Weber E, Sigaux N, Louvrier A. MR-guided navigation for botulinum toxin injection in the lateral pterygoid muscle. First results in the treatment of temporomandibular joint disorders. J Stomatol Oral Maxillofac Surg. 2019;120(3):188-195. doi:10.1016/j.jormas.2018.11.002
• Martenot A, Devoti JF, Pons M, et al. Persistent myogenic temporomandibular disorders: are navigation-guided botulinum toxin-A injections into the lateral pterygoid muscles effective?. J Stomatol Oral Maxillofac Surg. 2024;125(5):101715. doi:10.1016/j.jormas.2023.101715
• Lee ST, Kim D, Park JH, Kwon TG. Ultrasound-guided intraoral Botulinum toxin injection into the lateral pterygoid muscle for chronic temporomandibular joint dislocation. J Korean Assoc Oral Maxillofac Surg. 2024;50(1):41-48.
• Skármeta NP, Espinoza-Mellado P, Chana P. Orofacial dystonia and other oromandibular movement disorders. InTech. 2018;10-36. doi:10.5772/intechopen.78607
• Machado D, Martimbianco ALC, Bussadori SK, Pacheco RL, Riera R, Santos EM. Botulinum toxin type a for painful temporomandibular disorders: systematic review and meta-analysis. J Pain. 2020;21:281-293. doi:10.1016/j.jpain.2019.08.011
• Lund JP, Donga R, Widmer CG, Stohler CS. The pain-adaptation model: a discussion of the relationship between chronic musculoskeletal pain and motor activity. Canad J Physiol Pharmacol. 1991;69(5):683-694. doi:10.1139/y91-102
• Gil-Martínez A, Grande-Alonso M, López-de-Uralde-Villanueva I, López-López A, Fernández-Carnero J, La Touche R. Chronic temporomandibular disorders: disability, pain intensity and fear of movement. J Headache Pain. 2016;17(1):103. doi:10.1186/s10194-016-0690-1
• Kucukguven A, Demiryurek MD, Kucukguven MB, Vargel I. A novel injection technique to the lateral pterygoid muscle for temporomandibular disorders: a cadaveric study. Plastic Reconstruct Surg. 2021;148(5):785e-790e.
• Mahan PE, Wilkinson TM, Gibbs CH, Mauderli A, Brannon LS. Superior and inferior bellies of the lateral pterygoid muscle EMG activity at basic jaw positions. J Prosthet Dent. 1983;50(5):710-778.
• Reiter S, Goldsmith C, Emodi-Perlman A, Friedman-Rubin P, Winocur E. Masticatory muscle disorders diagnostic criteria: the American Academy of Orofacial Pain versus the research diagnostic criteria/temporomandibular disorders (RDC/TMD). J Oral Rehabil. 2012;39(12):941-947. doi:10.1111/j.1365-2842.2012. 02337.x
• Finden SG, Enochs WS, Rao VM. Pathologic changes of the lateral pterygoid muscle in patients with derangement of the temporomandibular joint disk: objective measures at MR imaging. AJNR Am J Neuroradiol. 2007;28(8):1537-1539. doi:10. 3174/ajnr.A0590