Continence and the Pelvic Floor

Julie CornishGeneral Surgical SpR

faecal incontinence

• affects 2-5% of population• increases with age• incidence in >50yrs age – 11% men– 26% women

• significant social stigma

Causes of incontinence

• Structural damage to muscles• Nerve disruption• Marked intestinal hurry

causes• If sphinctor normal– faecal impaction (immobility, medication, parkinsons)– IBD, IBS

• If sphinctor abnormal– Disruption of sphinctor ring due to trauma– Surgical trauma (haemorrhoidectomy)– Complete rectal prolapse– LMN lesion– Muscle atrophy– Congenital abnormality (anorectal atresia)

Obstetric causes

• 10-30% women post VD have signif sphinctor injuries

• Full thickness tears –rare• Prolonged childbirth assoc with damage to

pudendal nerve• Denervation of pelvic floor leads to sphinctor

atrophy in later life

investigation

• Hx– Detailed obstetric hx– Past perianal operations– Defaecation hx– Incontinent to gas/liquid/solids– Urinary incontinence– review medications (e.g. laxatives)

• Examination (don’t forget pr)

investigations

• Anal manometry• Endoscopy• Endoanal USS• Pudendal nerve terminal motor latency

studies• Defacating proctogram• MRI – spine /pelvis

Anorectal manometry• Use– sensory or muscular defects– functional weakness of internal and external

sphinctor• measures pressure of sphinctor muscles,

sensation in the rectum and anal reflexes• can use water or air filled balloons

Anal manometry 2

• Resting and squeeze pressures over anal canal• HPZ – high pressure zone• = length of the anal canal through which the

pressures >50% of the average maximum• Normal values– 40-70ml (threshold)– 60-130 ml (urgency sensation)– Maximum tolerated volume 150-230ml

Pudendal nerve latency studies

• St Marks pudendal electrode• Mounted on volar side of index finger• Four cables emit electrical stimulation• Latency (ms) = from onset of stimulus to first

deflection• Normal values = 2.0 +/- 0.2ms

Non operative management• medication (bulking agents, anti-diarrhoeals)

• specialist dietary assessment• pelvic floor exercises– bowel retraining (education about how the bowel works, and training to

modify bowel function)

– biofeedback (this includes aspects of bowel retraining and also physical treatments to improve bowel and pelvic floor coordination)

• rectal irrigation• anal plugs• repair of a localized sphincter defect

Injection of bulking agents

• Used for weakened or deficient internal sphinctor muscle

• Only limited evidence for use currently• Trials ongoing for PTP and collagen implants

Sacral nerve stimulation

• temporary/permanent• lead threaded down to S3 via spinal needle• GA• Current 0.5 – 3mA at 15 pulse/second• Temporary - 3 weeks• change to permanent if >50% improvement in

incontinence episodes + subjective improvement in symptoms

When do you operate?

When do you operate?

• Correction of some congenital abnormalities• Complete rectal prolapse • Simple disruption of external sphinctor (sphinctor

repair)

• Severe incontinence– implantation of artificial bowel sphinctor– graciloplasty– stoma

When might you consider a stoma?

stoma

• Complex Crohns• Rectovaginal fistula• Extensive injury (e.g cloacal)