Levator plate descent correlates with levator ani muscle deficiency

Measurements such as the minimal levator hiatus dimension, levator plate angle, iliococcygeal angle, and anorectal angle have been used for assessing the impact of levator damage on static and dynamic imaging features. The primary aim of this study was to investigate the association between levator ani muscle deficiency (LAD) and the position of the levator plate.

3D endovaginal ultrasounds of 186 women were reviewed. The levator ani muscle groups, the puboanalis, puborectalis, and pubovisceralis, were scored for abnormalities, (0 no defect and 3 total absence of the muscle). The levator plate descent angle, minimal levator hiatus dimensions, and the anorectal angle were measured. Levator plate descent towards the perineum was assessed and correlated with levator ani muscle deficiency.

The correlation between puborectalis scores and minimal levator hiatus area, anorectal angle and levator plate descent angle were 0.43 (P < 0.0001), 0.22 (P = 0.0045), and -0.40 (P < 0.0001), respectively. The correlation between pubovisceralis scores and minimal levator hiatus area, anorectal angle and levator plate descent angle were 0.36 (P < 0.0001), 0.38 (P < 0.0001), and -0.40 (P < 0.0001), respectively. The correlation between the total levator ani muscle scores and the minimal levator hiatus area, anorectal angle and the levator plate descent angle were 0.45 (P < 0.0001), 0.31 (P < 0.0001), and -0.45 (P < 0.0001) respectively.

Worsening LAD score is associated with levator plate descensus and with decreasing levator plate descent angle. We can use levator plate descent angle along with the minimal levator hiatus and anorectal angle as objective measurements to assess levator ani muscle deficiency.