Complete Penile Amputation: An Anatomical Reference and Surgical Pearls to Ensure a Successful Replantation

Case 1

A 38-year-old male with unmedicated schizophrenia presented to the emergency department (ED) with numerous self-inflicted stab wounds to the face, neck, and a completely amputated penis injury (Figure 1a). After a thorough trauma evaluation, the patient was taken emergently to the operating room for a neck exploration. Intraoperatively, the plastic surgery and urology teams prepared the amputated penis on the back table, identifying and labeling the structures to repair. The urologists performed the urethral anastomosis and placed both a 16 French indwelling Foley and a suprapubic catheter, while the plastic surgery team repaired the corpus cavernosum, 1 dorsal vein, 2 dorsal nerves, and 2 dorsal arteries (Figure 1b and 1c). The vessels were anastomosed with use of a microscope by performing simple interrupted sutures starting at the back wall.

On postoperative day (POD) 3, the penis appeared edematous (Figure 1d); leech therapy was applied from POD 4 to 13 to relieve venous congestion (Figure 1e). On POD 20, the patient underwent eschar debridement and split thickness skin grafting. The patient was discharged to an inpatient psychiatric unit where he continued to be followed by the surgical teams but was ultimately sent home 6 weeks after initial presentation. The patient developed subcoronal hypospadias 3 months postoperatively. Urology attributed this to the tension and pressure from prolonged use of the indwelling Foley. Despite this, on 7-month follow-up the patient had regained full sensation distal to the site of repair, intact erectile function, and good micturition without incontinence or stricture, as well as being subjectively very happy and thankful for the treatment and care he received.

Case 2

A 20-year-old male with depression presented to the ED following an isolated self-inflicted complete penile amputation (Figure 2a and 2b). The patient was emergently taken to the operating room with urology and plastic surgery, during which a suprapubic catheter was placed and the corpus cavernosum, dorsal nerves, dorsal arteries, and dorsal vein were anastomosed. However, due to duskiness of the proximal penile skin, the patient was taken back to the operative room 6 hours postoperatively to check and ultimately revise the anastomosis of the dorsal arteries to improve perfusion to the proximal skin (Figure 2c).

During the first 2 weeks postoperatively, the patient developed mild edema and necrosis of the proximal skin of his penis (Figure 2d). These issues were managed nonoperatively and had completely resolved by his 2-month follow-up. On 8-month follow up, the patient reported full physiologic function including the ability to sustain an erection and micturate and similarly was subjectively very pleased and thankful.

Penile amputation is a rare yet challenging injury requiring emergent multidisciplinary surgical intervention and diligent postoperative care. Total penectomy (AAST Grade V) requires penile replantation and may be necessitated following self-mutilation, accidental trauma, or violent assault. Since the first successful penile replantation in 1929,¹ over 100 cases have been documented with high salvage and varying complication rates.^2,3 Microsurgical replantation with anastomosis of the dorsal vein, penile arteries, and dorsal nerves is the current standard of treatment for these injuries.⁴

A detailed overview of the anatomy of the male genitourethral system can be found in any anatomical atlas. The high yield anatomy pertinent to replantation surgery is presented in Figure 3. The penis consists of 3 parts including the base, shaft (body or corpus), and glans. The shaft is made from 3 columns of erectile tissue: the left and right corpora cavernosa and the corpus spongiosum, which are all innervated by the parasympathetic fibers of the pelvic splanchnic nerves (S2, S3, S4). Arterial supply of the penis originates from the anterior branch of the internal iliac artery. This artery then branches off into the deep internal pudendal arteries, giving rise to the common penile artery before dividing into (1) the bulbourethral artery, providing perfusion to the bulb; (2) the cavernosal artery, deep artery of the penis providing perfusion to the corpus cavernosum; and (3) the dorsal artery, providing perfusion to the glans and corpus spongiosum. The deep dorsal vein drains the venous system of the deeper structures of the penis and drains into the periprostatic venous plexus. The cutaneous innervation of the penis is from the left and right dorsal nerves, which originate from the pudendal nerve.⁵   

There are 5 key points that are critical to a successful replantation:

• Knowledge of penile anatomy: refer to Figure 3.
• Urinary diversion along with urethral stenting: perform a suprapubic cystostomy to drain the bladder and insert a Foley catheter to stent the urethra across the repair.
• Microsurgical repair: repair dorsal vein, dorsal arteries, and dorsal nerves.
• Avoid proximal skin necrosis: avoid aggressive dissection of the skin off the dorsal artery, dorsal vein, or the nerve, which can cause necrosis of the skin (especially the proximal skin).
• Repair of the cavernous arteries: in addition to the dorsal artery, repair of the corpus augments inflow and function during erection.

Microsurgical vascular anastomoses of the neurovascular dorsal structures ensure adequate blood supply to surrounding tissues, but maintaining adequate supply to the entirety of the skin represents a challenge. The most common complication of microsurgical replantation involves development of proximal skin necrosis. Unfortunately, proximal skin necrosis is often an unavoidable process owing to the injury and inability of surgeons to reconstitute the blood supply from the external pudendal arteries to the shaft skin.⁶ Traditional teaching has been that inflow anastomosis via the dorsal arteries will improve perfusion. However, these arteries are only responsible for perfusing the distal skin and deep structures of the penis. The external pudendal artery serves as the primary blood supply to the majority of shaft skin, which explains the proximal skin necrosis seen in case 2. Additionally, venous outflow is critical to replantation surgery, and when restoring appropriate outflow is difficult or becomes challenged, management via medicinal leech therapy has been well documented.^7,8   

Lastly, measures are also necessary to prevent tertiary postoperative complications, including development of hypospadias. In case 1, prolonged Foley catheter use predisposed the patient to a hypospadias, a rare complication of long-term indwelling catheters with only a few cases documented.⁹

Complete self-inflicted penile amputation is an infrequent surgical and psychiatric emergency. The paucity of penile amputation cases remains a challenge to studying techniques for improved outcomes; however, the overwhelming success rate of replantation and high rates of patient satisfaction validate the usefulness of the procedure.^2,3 Our case series highlights the importance of understanding penile anatomy as well as specific pearls to a successful replantation. This outline offers a quick and easy guide to assist future surgeons who encounter this rare yet interesting challenging case.

Affiliations: ¹Division of Plastic and Reconstructive Surgery, Department of Surgery, University of Louisville, Louisville, KY; ²Department of Surgery, Robert Wood Johnson Medical School, New Brunswick, NJ; ³School of Medicine, University of Louisville, Louisville, KY; ⁴Division of Plastic and Reconstructive Surgery, Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA

Correspondence: Milind D Kachare, MD; Milind.Kachare@gmail.com

Disclosures: The authors have no relevant financial or nonfinancial interests to disclose.