Hourglass Penis: Why Erections Can Look Narrow or Indented While Standing
Many men notice their penis looks different during an erection than they expect. One common concern is an hourglass penis, where the shaft narrows or has an indentation in a specific area. This “hourglass deformity” is often more noticeable when standing, as gravity, posture, blood flow, and pelvic floor activity all have greater influence in that position.
This change can be connected to hard flaccid syndrome, a condition involving pelvic floor muscle overactivity, altered penile blood flow, fascial restriction, and nerve involvement. In some cases, it may also overlap with Peyronie’s disease, which involves scar tissue in the penis. Understanding the anatomy helps explain why hourglass deformities and erection narrowing occur.
The Anatomy of Erections
The penis contains two corpora cavernosa, which provide rigidity, and one corpus spongiosum, which surrounds the urethra and expands into the glans. Surrounding these tissues is the tunica albuginea, a strong connective tissue sheath. Its inner circular fibers help trap blood during erection, while its outer longitudinal fibers distribute pressure evenly along the shaft.
For a uniform erection, the corpora cavernosa must expand evenly against a healthy tunica albuginea. If one region of the tunica or erectile chambers does not expand normally, a visible narrowing, indentation, or “hourglass” appearance develops.
Fascia Layers of the Penis
The penis is supported by multiple layers of fascia, which help regulate structure and blood flow.
Buck’s fascia (deep penile fascia): Encases the corpora cavernosa and corpus spongiosum, and contains the deep dorsal vein, dorsal arteries, and dorsal nerves. Restriction or scarring in Buck’s fascia can compress vessels, causing uneven engorgement and erection narrowing.
Dartos fascia (superficial fascia): Found beneath the skin, containing smooth muscle and connective tissue. It regulates scrotal temperature and skin mobility.
Colles’ fascia (superficial perineal fascia): Connects penile fascia into the perineum and lower abdomen. Restrictions here can transmit pelvic tension into the shaft, creating tethering that exaggerates an hourglass deformity.
Because these fascia connect into the pelvis, tightness from posture, chronic pelvic floor tension, or scar tissue can directly affect penile expansion during erections.
Hard Flaccid Syndrome and Hourglass Penis
Hard flaccid syndrome is a condition where the penis feels semi-rigid while flaccid, often with pain, burning, or altered sensation. Men with hard flaccid frequently report changes in erection quality, including indentations, hourglass narrowing, or weaker erections.
The main contributors include:
Pelvic floor muscle overactivity: The ischiocavernosus and bulbospongiosus muscles at the base of the penis compress veins and arteries when tight, limiting blood inflow and outflow balance.
Fascial restrictions: Tightness in Buck’s fascia, Colles’ fascia, or pelvic fascia tethers the penis, preventing smooth pressure distribution and causing deformity.
Tunica albuginea stress: Uneven pressure leads to weak spots in the tunica, preventing full expansion.
Nerve involvement: The pudendal nerve provides sensation and motor control to pelvic floor muscles. Irritation can worsen overactivity. The hypogastric nerve, part of the sympathetic nervous system, regulates penile vascular tone. Overactivation can constrict penile arteries and veins, worsening irregular filling and contributing to an hourglass shape.
Gravity and posture: Standing increases pelvic floor muscle activity and fascial loading. Gravity also exaggerates uneven blood distribution, making deformities more visible upright.
Hard Flaccid vs. Peyronie’s Disease
It is important to distinguish between functional problems and structural disease.
Hard flaccid syndrome and fascial dysfunction cause variable symptoms that change with position, stress, or muscle tone. The hourglass deformity may be worse while standing but improve when lying down.
Peyronie’s disease is caused by scar tissue in the tunica albuginea. It produces a fixed deformity, curvature, or hourglass narrowing that does not change with posture. Men with Peyronie’s often also experience painful erections.
How Pelvic Floor and Fascial Therapy Helps
Treatment for hourglass penis linked to hard flaccid syndrome focuses on restoring pelvic balance:
Manual release of pelvic floor muscles to reduce vessel compression at the penile base
Fascial therapy, such as myofascial release or counterstrain
Breathing and diaphragm retraining to reduce sympathetic overdrive and normalize pelvic pressure
Neuromuscular retraining of the ischiocavernosus and bulbospongiosus to improve erection support
Postural correction and joint mobilizations to the spine to decrease fascial strain through the pelvis and abdomen
Bottom Line
An hourglass-shaped penis, especially during erections while standing, may be caused by hard flaccid syndrome, fascial restriction, pelvic floor muscle overactivity, or nerve involvement. Stress, posture, and muscle tension can change erection quality.
By addressing fascial health, calming sympathetic nervous system overdrive, and retraining the pelvic floor, pelvic floor therapy can help restore more uniform erections, reduce pain, and improve sexual health.
If deformities are fixed or worsening, it is important to see a urologist to rule out Peyronie’s disease or other vascular causes.
Experiencing hard flaccid syndrome? Reach out to us at Pelvic Health Center in Madison, NJ to set up an evaluation and treatment! Feel free to call us at 908-443-9880 or email us at receptionmadison@pelvichealthnj.com.