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.