The superficial transverse perineal muscle is a thin, variable muscle in the superficial perineal pouch, running from the ischial tuberosity to the perineal body. It stabilises the perineal body — the central fibromuscular node of the perineum — alongside the external anal sphincter and the bulbospongiosus.
| Origin | Ischial tuberosity medial surface |
|---|---|
| Insertion | Perineal body (central tendon of the perineum) |
| Nerve Supply | Perineal branch of the pudendal nerve (S2, S3, S4) |
| Blood Supply | Perineal artery |
| Actions | Stabilises the perineal body; Assists in maintaining pelvic floor support |
|---|
The superficial transverse perineal muscle is disrupted in third and fourth-degree perineal tears during childbirth, where the tear extends through the perineal body. Episiotomy repair reconstructs the perineal body by approximating this muscle alongside the bulbospongiosus and external sphincter. It is identified in Fenton repair for perineal tightness and dyspareunia.
Not directly palpable. Its integrity is assessed by perineal body examination during pelvic floor assessment.
Third-degree perineal tear disrupting the superficial transverse perineal muscle and external anal sphincter producing perineal body deficiency and bowel control impairment, repaired by end-to-end or overlap sphincteroplasty.