Study on Hair Distribution in Healthy Males for Hair Restoration Design

Background: The incidence of hair loss among Chinese male has increased to 21.3 per hundred. Hair restoration has been an effective technique. Detailed hair distribution has a tremendous impact on the surgery design. Objective: To investigate the pattern of hair distribution in Chinese young adult males. Methods: A total of 1000 males without hair disease were enrolled. We evaluated the locations of the main anatomical marks at different sites on the scalp and analyzed the hair density and follicular unit structure using the standard photographs and trichoscope. Results: The hairline shapes were classified as: linear (48.7%), linear with central protrusion (27.9%), round (9.8%), round with central protrusion (13.7%). The average height of the median line was 6.78 +/- 0.75 cm, the ratio of the median line and the forehead height was 0.333. The average distance from the parietal whorl to the vertical bimeatal line was 7.05 +/- 3.32 cm, and most of the PWs were on the right (51.4%) and had a clockwise pattern (73.3%). The hair density was 171.12 +/- 18.32 hairs/cm(2) in the vertex. 1-hair follicular units were (75.90% and 56.39%) in anterior hairline and temporal area. Conclusion: Our study clearly assisted understanding of scalp anatomy and hair distribution in Chinese young adult males.