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Published on: March 1, 2015
Surgical consideration of the anatomic origin of the risorius in relation to facial planes
Jung-Hee Bae1, Joo-Heon Lee1, Kwan-Hyun Youn1
1Ms Bae is an anatomic researcher and a PhD candidate in the division in Anatomy and Developmental Biology, Human Identification Research Center, BK21 PLUS Project, Yonsei University College of Dentistry, Seoul, KoreaDr Youn is a medical artist, anatomist, and researcher; and Drs Hu and Kim are anatomists, professors, and researchers in the Division in Anatomy and Developmental Biology, Yonsei University College of Dentistry, Seoul, South KoreaDr Lee is a plastic surgeon in private practice in Seoul, South KoreaDr Hur is an anatomist, professor, and researcher in the Department of Anatomy, Kwandong University College of Medicine, Gangneung, South KoreaDr Tansatit is a professor and an anatomist in the Chula Soft Cadaver Surgical Training Center and the Department of Anatomy, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Background:
Confusion exists as to the plane of the risorius with respect to the superficial musculoaponeurotic system (SMAS), the parotid fascia, and the masseteric fascia, which generally are considered origins of the risorius.
Objectives:
The authors attempted to clarify the origin of the risorius by topographic examination and dissection, which would provide valuable anatomic information for flap dissection in facelift surgery.
Methods:
Detailed dissection was performed in the perioral region of 46 cadaveric specimens to discern the origin of the risorius in relation to the fascial layer. The anatomic aspects of the muscular arrangement and origin of the risorius were classified according to the location of attachment.
Results:
The risorius originated solely from the fascial layer superficial to the SMAS in 27 specimens (58.7%; type A). It originated solely from the masseter tendon in 3 specimens (6.5%; type B) and from the fascial layers, both superficial and deep to the SMAS, in 16 specimens (34.8%; type C).
Conclusions:
The patterns of risorius origination identified in this study represent important anatomic reference information for flap dissection in facelift surgery.
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