- Rhomboid marked out. All sides equal. Includes all disease
- Flap marked out - lateral line the same length as rhomboid edges and a perpendicular line caudally.
- Caudal point off midline
- Blue dye injected into sinus to confirm all sinus is excised
- Dissection down to pre-sacral fascia
- Flap is then raised and includes fasica of glut maximus
- Drain in cavity
- Corners sutured in place first
- Mattress sutures
