Biomechanical analysis of anchoring points in rhytidectomy.

OBJECTIVE To quantify tissue tearing force at various anchoring points on the face. METHODS This is a prospective anatomic study using 4 fresh cadavers of persons aged 60 to 70 years at the time of death, for a total of 8 sides. Standardized 1-cm distances were measured at the various anchor points, and a single 0 Prolene suture loop was tied at each standardized anchoring point. Steady force was applied perpendicular to the plane of the face with a digital hanging scale. The scale was pulled until the suture ruptured the tissue at the anchoring point. The values at which the tissue ruptured were recorded, averaged, and compared. RESULTS The average tissue force was 7.01 kg for the root of the zygoma vs 3.44 kg for the temporalis fascia (P < .05). The average tissue force was 5.50 kg for infralobular tissue vs 4.09 kg for tissue of the superficial musculoaponeurotic system located 1 cm anterior to the infralobular tissue (P < .05). The force for the fascia of the sternocleidomastoid was 3.89 kg vs 5.57 kg for the mastoid fascia (P < .05). There was a statistically significant difference between vertical bites of the temporalis fascia at 1.90 kg vs horizontal bites of the temporalis at 5.01 kg (P < .05). CONCLUSION The tissue tearing force varies by location on the face as well as suture orientation.