Muscle Foreshortening after Free Gracilis Transfer for Smile: Where? When? Why?

Area of Science:

• Plastic Surgery
• Facial Reanimation Surgery
• Microsurgery

Background:

• Gracilis free muscle transfer (GFMT) is the standard for smile restoration in longstanding facial palsy.
• Resting oral commissure lateralization (ROCL) is a common complication, causing aesthetic and functional issues.
• Risk factors for ROCL after GFMT are not well understood.

Purpose of the Study:

• To identify risk factors associated with resting oral commissure lateralization (ROCL) following gracilis free muscle transfer (GFMT) for smile restoration.

Main Methods:

• A facial nerve database was used to identify patients with ROCL after GFMT (2003-2021).
• Medical records were reviewed to determine potential risk factors for muscle foreshortening.
• Statistical analysis was performed to assess the significance of identified factors.

Main Results:

• 10% of 412 GFMT patients developed ROCL.
• Highest ROCL rates were associated with ipsilateral cranial nerve VII (27.3%) and dual innervation (15.4%).
• Prior radiation (22%) and concurrent fascia lata suspension (20.8%) significantly increased ROCL risk compared to controls.

Conclusions:

• Innervation source, history of radiation, and concurrent fascia lata static suspension are significant risk factors for ROCL after GFMT.
• Understanding these factors can help optimize surgical techniques and patient selection.
• Further research may focus on mitigating these identified risks for improved outcomes.