Hypospadias

Hypospadias is a congenital abnormality in which the urethral meatus opens on the ventral surface of the penis proximal to its normal position at the tip of the glans.

The characteristic triad is:

• Ventral ectopic urethral meatus
• Ventral penile curvature, or chordee, of variable severity
• Dorsal hooded prepuce with deficient ventral foreskin

Anatomical classification

Distal

• Glanular
• Coronal
• Subcoronal

Mid penile

Meatus along the penile shaft.

Proximal

• Proximal penile
• Penoscrotal
• Scrotal
• Perineal

Meatal location alone does not determine severity. A child with distal meatus but major curvature can have a more challenging reconstruction than a child with a more proximal meatus and little curvature.

Assess:

• Meatal position
• Glans size
• Urethral plate quality
• Degree of curvature
• Penile length
• Ventral skin deficiency
• Penoscrotal transposition
• Testicular position

Do not circumcise an infant with hypospadias before paediatric urology assessment because preputial tissue may be required for reconstruction.

Disorder of sex development concern

Proximal hypospadias with:

• Bilateral nonpalpable testes
• Severe micropenis
• Bifid scrotum
• Other genital ambiguity

requires endocrine and genetic assessment before routine hypospadias surgery.

Diagnosis is clinical.

Routine renal ultrasound is unnecessary for isolated distal hypospadias.

Investigate urinary tract or endocrine anatomy selectively when:

• Proximal severe hypospadias
• Undescended testes
• Recurrent urinary infection
• Other congenital anomalies

Curvature assessment

The true severity of chordee is best assessed intraoperatively after penile degloving using an artificial erection test.

Curvature above approximately 30° is generally considered clinically significant and should be corrected.

Timing

Primary repair is generally performed between 6 and 18 months of age.

The objectives are:

• Straight penis
• Adequate calibre urethra
• Meatus at or near the glans tip
• Forward directed urinary stream
• Durable ventral skin coverage
• Good cosmetic and later sexual function

Distal and many mid penile lesions

The most widely used operation is the tubularised incised plate repair, commonly called TIP or Snodgrass repair.

Steps include:

• Penile degloving
• Correct minor residual curvature
• Midline incision of a narrow urethral plate where necessary
• Tubularise the plate over a catheter or stent
• Cover the neourethra with a vascularised second layer, commonly dartos
• Glansplasty
• Skin reconstruction

The interposed vascularised layer reduces urethrocutaneous fistula risk.

Significant curvature

Correct curvature before committing to urethral reconstruction.

Initial measures include:

• Complete penile degloving
• Release of abnormal ventral tethering tissue

If clinically important curvature persists:

Dorsal plication

Suitable for selected moderate residual curvature, but causes some penile shortening.

With severe ventral curvature, particularly proximal hypospadias, correction can require:

• Urethral plate transection
• Ventral corporal lengthening
• Grafting

This usually changes the urethral reconstruction strategy.

Proximal hypospadias

When the urethral plate can be preserved and the penis straightened, an onlay flap or selected tubularised reconstruction can be used.

When severe curvature requires plate transection, a staged repair is often preferred.

Typical two stage reconstruction:

Stage 1

• Straighten penis
• Excise poor ventral tissue where necessary
• Place inner preputial or buccal mucosal graft onto ventral penis

Allow graft maturation.

Stage 2

Several months later:

• Tubularise the graft
• Add vascularised tissue coverage
• Perform glansplasty

Staged approaches have become increasingly important for severe proximal disease because forcing a one stage reconstruction through poor tissue increases stricture and recurrent curvature risk.

Preoperative androgen treatment

Testosterone can increase glans and penile size in selected proximal cases with a very small penis or narrow glans.

Evidence for routine use is inconclusive.

If used, stop therapy sufficiently before surgery because increased vascularity can increase intraoperative bleeding.

Urinary drainage

A transurethral stent is commonly left after urethroplasty.

Duration depends on:

• Repair complexity
• Surgeon protocol
• Distal versus proximal reconstruction

There is no single universally superior catheter duration.

Routine prolonged antibiotic prophylaxis after uncomplicated distal repair has not clearly reduced infection or long term urethral complications.

Complications

Important complications include:

Urethrocutaneous fistula

Urine exits through an abnormal ventral opening.

Small early fistulas can occasionally close, but persistent lesions usually require delayed surgical repair after inflammation settles.

Meatal stenosis

Produces narrow or spraying urinary stream.

May require meatotomy or revision.

Urethral stricture

More common after proximal or staged reconstruction.

Requires careful assessment rather than repeated blind dilatation.

Glans dehiscence

Partial or complete separation of glans reconstruction.

Urethral diverticulum

Often results from distal obstruction or poorly supported neourethra.

Recurrent chordee

Can become apparent during growth and puberty.

Long term follow up into adolescence is particularly important after proximal repairs because some complications become evident only with penile growth and sexual maturation.