Comparison of Objective Outcomes in Dynamic Lower Facial Reanimation With Temporalis Tendon and Gracilis Free Muscle Transfer

Question  What are the objective differences in oral commissure position and smile excursion between facial reanimation with temporalis tendon transfer and gracilis free muscle transfer?

Findings  In this case series of 28 patients, oral commissure symmetry and smile excursion improved with both temporalis tendon transfer and gracilis free muscle transfer. Improvement in excursion was greater among patients treated with a gracilis free muscle transfer compared with temporalis tendon transfer.

Meaning  While both interventions improve oral symmetry and smile excursion, there appears to be better excursion, on average, with gracilis free muscle transfer.

Importance  Facial paralysis affects patients’ physical, social, and psychological function. Dynamic smile reanimation can mitigate these effects, but there are limited data to guide the surgeon in selecting the best reanimation procedure for each patient.

Objective  To compare quantitative changes in oral commissure symmetry and smile excursion following temporalis tendon transfer (T3) and gracilis free muscle transfer.

Design, Setting, and Participants  Retrospective case series of 28 adults with unilateral facial paralysis seeking dynamic lower facial reanimation at a tertiary academic medical center between July 1, 2010, and July 30, 2014. Data were analyzed from May 1, 2016, to June 30, 2016.

Interventions  Minimally invasive T3 (n = 14) compared with gracilis free muscle transfer (n = 14).

Main Outcomes and Measures  Measured symmetry of the oral commissure between the healthy and paralyzed sides in the horizontal, vertical, and angular dimension and excursion of the paralyzed commissure following reanimation compared with the healthy commissure.

Results  Of the 28 patients, 19 (68%) were women; mean (SD) age was 51.7 (17) years. Commissure symmetry during smile improved significantly for the T3 patients in the vertical and angular dimensions, and the gracilis free muscle transfer patients had significant improvement in the vertical and horizontal dimensions. Commissure excursion significantly improved in both groups following surgery, with a larger improvement seen in the gracilis free muscle transfer group (11.3 mm; 95% CI, 7.0 to 15.5 mm) compared with the T3 group (4.8 mm; 95% CI, 0.2 to 9.3 mm), with a mean difference of 6.5 mm (95% CI, 0.7 to 12.4 mm; Cohen d, 0.86). Postoperative smile excursion of the paralyzed side was within 1.0 mm of the healthy side in the gracilis free muscle transfer group (95% CI, −2.1 to 4.0 mm).

Conclusions and Relevance  Temporalis tendon transfer and gracilis free muscle transfer both improve oral commissure symmetry and excursion in facial paralysis. The improvement in smile excursion appears to be larger in patients treated with gracilis free muscle transfer and, on average, the excursion approximates the contralateral healthy side.