This article explores the mechanisms trans masculine individuals use to achieve functional rigidity following gender-affirming phallic reconstruction. Achieving a rigid phallus is important for many trans men, as it directly impacts sexual health, quality of life, and the ability to engage in penetrative sexual activity. The process involves hormonal changes and advanced surgical techniques, often culminating in the use of specialized internal devices.
The Role of Testosterone and Tumescence
Long-term testosterone therapy induces several physical changes, most notably the enlargement of existing genital tissue, often called “bottom growth” or clitoral hypertrophy. This tissue is homologous to the penile tissue in cisgender men and responds directly to testosterone by increasing in size and density. Growth typically ranges from 1 to 4 centimeters, though this varies significantly based on genetics and duration of treatment.
Testosterone also increases blood flow and nerve responsiveness, allowing the enlarged tissue to achieve tumescence, or engorgement, when sexually aroused. This natural response provides a degree of firmness and increased visibility, which can be sufficient for some individuals. However, the resulting rigidity is generally limited and often insufficient to allow for penetrative sexual intercourse.
Surgical Options for Phallic Construction
Two primary surgical pathways exist for phallic construction: Metoidioplasty and Phalloplasty. Metoidioplasty is a less invasive procedure that utilizes the existing, hormone-enlarged tissue. The surgeon releases the surrounding ligaments, allowing the tissue to drop and appear more prominent, effectively creating a microphallus.
The advantage of Metoidioplasty is the preservation of native sensation and the inherent ability of the tissue to achieve natural, limited tumescence without an internal device. The resulting phallus is typically shorter (4 to 6 centimeters) and, while it may allow for standing urination, it often lacks the length and rigidity required for penetration.
Phalloplasty is a more complex, multi-stage procedure that constructs a larger phallus using tissue grafts, typically taken from the forearm, thigh, or back. This procedure is chosen when the primary goal is a phallus closer to the size of a cisgender penis, with a higher potential for penetrative capability. Because the tissue used in Phalloplasty does not contain erectile bodies, it requires the later surgical placement of an internal device to achieve functional rigidity.
Devices Used to Achieve Functional Rigidity
Individuals who undergo Phalloplasty rely on the surgical implantation of a prosthetic device to achieve a firm erection. This procedure is typically performed months or a year after the initial construction to allow the tissue to heal. These devices are generally categorized into two types: semi-rigid (malleable) and inflatable penile prostheses (IPP). The choice of device is a personal one, balancing ease of use, aesthetic outcome, and mechanical reliability. The surgeon and patient discuss these factors extensively before making a final decision.
Semi-Rigid Implants
Semi-rigid implants consist of a pair of bendable rods, usually silicone surrounding a metal core, placed within the neophallus. This device keeps the phallus permanently firm but allows it to be manually bent upward for sexual activity and downward for concealment. Malleable rods involve a less complex surgery and have a lower risk of mechanical failure. However, they do not allow the phallus to achieve a truly flaccid state.
Inflatable Penile Prostheses (IPP)
The three-piece Inflatable Penile Prosthesis is the most common option for replicating a more natural erectile function. This system includes two inflatable cylinders placed inside the neophallus, a fluid-filled reservoir implanted under the abdominal wall, and a pump and release valve placed within the scrotum. To achieve rigidity, the pump is squeezed, transferring fluid from the reservoir into the cylinders, resulting in a firm phallus.
When the user wishes to end the erection, a valve on the pump is pressed, returning the fluid to the reservoir, allowing the phallus to become fully flaccid. The inflatable device offers better concealment when deflated, but the surgery is more complex and carries a higher potential for mechanical complications or infection. Because the neophallus lacks the tough corporal tissue of a natal penis, the prosthesis must often be anchored to the pubic bone to ensure stability during use.