Hard flaccid syndrome symptoms, comorbidities, and self-reported efficacy and satisfaction of treatments: a cross-sectional survey.

Hard flaccid syndrome (HFS) is a poorly understood condition with no formal consensus on its definition. We aimed to advance the understanding of HFS by evaluating symptom prevalence, cause of symptom onset, comorbidities, and self-reported efficacy and satisfaction with current treatments. An online, open, 42-question survey on Qualtrics with purposive and convenience sampling methods was conducted between May 9 and June 9, 2023 on participants self-identifying as having HFS. Participants were recruited through social media platforms. Only 58.0% of participants reported their HFS symptoms began following a specific incident/injury. Changes in penis shape/size (92.3%) and rigid penis when not erect (90.9%) were the most common complaints. Activities such as laying down and stretching improved symptoms in 73.0% and 44.1% of the participants, respectively, while masturbation and standing worsened symptoms in 75.9%, and 64.5% of the participants, respectively. Pudendal neuralgia (16.9%) was the most prevalent comorbid condition. Of those who participated in therapies, phosphodiesterase-5 (PDE5) inhibitor treatment had the highest patient global impression of change (PGIC) score (2.6 ± 1.1), indicating little to moderate improvement in symptoms. All other therapies scored between 1 and 2, indicating no change to little improvement in symptoms: pelvic floor physical therapy (PFPT) (1.8 ± 0.9), shockwave therapy (1.6 ± 1.1), diet/nutrition changes (1.6 ± 0.8), nerve blocks (1.6 ± 0.8), muscle relaxants (1.5 ± 0.6), anti-inflammatory medications (1.5 ± 0.7), cognitive therapy (1.4 ± 0.7), and nerve pain medications (1.4 ± 0.5). Overall, a direct injury to the penis may not necessarily be the only cause of HFS for some patients, and current therapies generally do not benefit most patients. A better understanding of the root causes of HFS and innovative treatment strategies are greatly needed for HFS patients.