Ischioanal fossa

• Between the pelvic sidewall (ischium, obturator internus) and levator ani
• Horseshoe-shaped recess with anterior recesses deep to perineum
• Infections around the anus can form large abscesses in the ischioanal fossa

Perineal Body and Episiotomy

• Perineal body may be torn during childbirth
• Episiotomy may be undertaken during instrumental (forceps or ventouse) delivery - mediolateral episiotomy recommended to avoid anal sphincter injuries
  • Median Incision Likely to Tear Further Posterior → EAS

Pudendal Nerve Block

• Administered During Childbirth to Block Sensation from Majority of Perineum & Lower 1/4 Vagina

Transvaginal

• Insert Digits into Vagina, Palpate Laterally for Ischial Spine
• Injection through Vaginal Mucous Membrane → Towards Ischial Spine, Through Sacrospinous Ligament ⇒ Inject
• Pudendal Nerve & ALL BRANCHES will be Bathed in Anaesthetic at this Location

OR: Perineal

• Palpate Ischial Tuberosity through Buttocks
• Inject ⇒ Pudendal Canal 1” Deep to Ischial Tuberosity

Digital Rectal Examination

• GI/GU Assessment
  • Anal/Rectal Mucosa (eg: polyps),
  • Prostate (prostate tumour - often diagnosed by DRE - feels rock hard; BPH feels ‘bulky’)
  • Posterior Vaginal Wall and Cervix
  • Muscle Tone in Levator ani and the Anal sphincter
• May be followed by Proctoscopy or Colonoscopy

Benign Prostatic Hyperplasia (BPH)