Long-term Follow-up of Unilateral Cleft Lip Repair Using the Trilobate Flap Combined with Nasolabial Muscle Tension System Reconstruction

Background: Unilateral cleft lip (UCL) repair often struggles to adequately lower the cleft-side philtral peak and achieve durable nasal correction. The trilobate flap technique redistributes tissue to the nasal tip, nasal base, and upper lip, while aligning the incision symmetrically with the contralateral philtral column. When paired with nasolabial muscle tension system reconstruction, it may better reproduce physiologic biomechanics and stability. Methods: We retrospectively reviewed UCL patients repaired by one senior surgeon (2010–2019) with ≥5-year follow-up. Standardized frontal and submental photographs were analyzed using predefined anthropometric indices. Pre- vs postoperative changes and postoperative symmetry were assessed. Postoperative measurements were further compared with age- and sex-matched normal individuals. Linear regression analyses were performed to identify factors associated with postoperative symmetry. Results: A total of 82 patients were included (54 with incomplete UCLs; 51 male; median surgery age 4.1 months; median follow-up 5.87 years). Philtrum and columellar angles, philtral height ratio, nostril width ratio, and nasal alar to oral width ratio all improved significantly (p < 0.001), approaching values observed in normal individuals. The nostril sill ratio postoperatively was 0.93 (IQR 0.84–1.13), showing no significant difference from normal individuals. Scars were camouflaged along the philtral column with natural nasolabial contours. Regression analysis showed that cleft severity was independently associated with residual nostril width asymmetry. Conclusions: The trilobate flap combined with reconstruction of the nasolabial muscle tension system yields significant, durable improvements in lip and nasal morphology and is a reliable option for primary UCL repair.