Clinical Types of Hypospadias
Hypospadias is classified primarily by the anatomical location of the urethral meatus, with additional consideration for associated penile abnormalities.
Classification by Meatal Position
Distal (Anterior) Hypospadias - Accounts for approximately 70% of cases, representing milder forms not typically associated with other urogenital deformities 1
- Glanular: Meatus located on the ventral aspect of the glans penis
- Coronal: Meatus located at the corona
- Distal shaft: Meatus located on the distal portion of the penile shaft
Proximal (Posterior) Hypospadias - Accounts for approximately 30% of cases, often more complex and may require more extensive reconstruction 2
- Midshaft: Meatus located on the middle portion of the penile shaft
- Proximal shaft: Meatus located on the proximal portion of the penile shaft
- Penoscrotal: Meatus located at the junction of the penis and scrotum
- Scrotal: Meatus located on the scrotum
- Perineal: Meatus located on the perineum (most severe form)
Associated Anatomical Abnormalities
Ventral curvature (chordee) - Abnormal downward curvature of the penis that often accompanies hypospadias and may require surgical correction 3
Dorsal hooded foreskin - Dorsally redundant prepuce with deficient ventral foreskin, creating a characteristic "hood" appearance 4
Atrophic corpus spongiosum - Underdeveloped spongy tissue surrounding the urethra, particularly in more proximal forms 2
Urethral plate abnormalities - The quality and width of the urethral plate significantly impact surgical approach and outcomes 5
- Normal urethral plate: Well-developed with adequate width
- Narrow urethral plate: Restricts surgical options
- Absent urethral plate: Requires more complex reconstruction
Clinical Significance of Classification
The location of the meatus and associated abnormalities determine the surgical approach and complexity of repair 3
Proximal hypospadias (especially penoscrotal, scrotal, and perineal) may warrant endocrinological evaluation to exclude disorders of sexual differentiation, particularly when accompanied by undescended testes 1
The GMS (Glans-Meatus-Shaft) scoring system is sometimes used for more comprehensive phenotyping beyond simple meatal position 5
Digital imaging and histological analysis of tissue samples (foreskin, glans, urethral plate, periurethral ventral skin) can provide additional phenotypic information to guide surgical planning 5
Surgical Considerations Based on Type
Distal hypospadias typically requires less complex procedures such as:
- MAGPI (Meatal Advancement and Glanuloplasty)
- TIP (Tubularized Incised Plate) technique according to Snodgrass 3
Proximal hypospadias often requires more extensive reconstruction:
- Staged repairs
- Vascularized foreskin flap-plasty
- Buccal mucosa grafts for severe cases 3
Clinical Evaluation
Physical examination should assess:
- Exact location of the urethral meatus
- Presence and severity of chordee
- Quality and width of the urethral plate
- Penile length and glans width
- Associated anomalies such as cryptorchidism 5
Standardized anthropometric measurements including penile length, urethral plate dimensions, and glans width provide objective data for surgical planning 5