Male genital sensation after spinal cord injury: a review

The effect of local anesthetic on the hypersensitive and nonsensitive areas of the penis is different in primary premature ejaculation: a pilot study

Background

Penile hypersensitivity is not the whole penis, but rather only a part of the penis. Though local anesthetic can prolong intravaginal ejaculation latency time by reducing penile hypersensitivity, the effect on the hypersensitive and nonsensitive areas of penis is still unclear.

Aim

The study aimed to explore whether the effect of local anesthetic on the hypersensitive and nonsensitive areas of the penis is different in premature ejaculation.

Methods

Penile neurophysiological tests were performed on 290 patients with primary premature ejaculation. The sensory threshold, latency, and amplitude were recorded before and after the topical application of a local anesthetic (lidocaine cream) on the penis.

Outcomes

Local anesthetics increased the sensory thresholds of hypersensitive and nonsensitive areas of the penis without difference but only prolonged the latency of the hypersensitive areas.

Results

According to the neurophysiological results, 149 of 290 patients with primary premature ejaculation had normal penile sensitivity and 141 had penile hypersensitivity. While penile hypersensitivity does not necessarily mean that the whole penis is hypersensitive, and may be that only a part of the penis is hypersensitive, and we examined the following hypersensitivities: glans hypersensitivity only (14 cases), shaft hypersensitivity only (77 cases), and whole penis hypersensitivity (50 cases). Local anesthetics (lidocaine cream) increased the sensory thresholds of hypersensitive and nonsensitive areas of the penis without difference (P < .001) but only prolonged the latency of the hypersensitive areas (P < .001), and the latency of the nonsensitive areas was not different (P > .05).

Clinical Implications

The present discovery implies that it is possible to improve ejaculation by applying local anesthetics externally to the hypersensitive areas of the penis to reduce the afferent local sensory signals, and improve intravaginal ejaculation latency time through accurately decreasing penile sensibility.

Strengths & Limitations

This is the first large-sample study to explore the difference of local anesthetics' effects on the hypersensitive and nonsensitive areas of the penis by means of neurophysiological methods in premature ejaculation. Our study exclusively examines alterations in penile evoked potential following electrical stimulation, which may not entirely encompass shifts in penile receptivity during sexual activity.

Conclusion

The effects of local anesthetics on the same penis varied with penile sensitivity, and can only prolong the latency of hypersensitive area of the penis. The effect of local anesthetic on the hypersensitive and nonsensitive areas of the penis is different in premature ejaculation.

Looking Beyond the Chair: Psycho-Perceptual Predictors of Sexual Distress and Sexual Satisfaction in Individuals with Spinal Cord Injury

Despite a large body of biomedical research, little is known about the psychological and perceptual predictors of sexual satisfaction (SS) and sexual distress (SD) post spinal cord injury (SCI). Guided by a bio-psycho-perceptual framework, this cross-sectional research aimed at assessing SS and SD in a large SCI sample using validated patient-reported outcome measures (PROM). Significant correlates and predictors of SS and SD were also identified. Ninety-one men and women with SCI completed PROMs of SS and SD, as well as psychological (mood, sexual and body esteem) and perceptual (interoceptive awareness, trait mindfulness, sexual mindfulness) factors. Neurological profiles were also assessed, along with experience of orgasm. Correlates of SS and SD were first identified using Pearson's correlations, then multiple hierarchical regression models were computed to isolate predictors. Orgasm experience and psychological factors emerged as moderate correlates of both SS and SD, while neurological factors did not. Interoceptive awareness and trait mindfulness showed weak associations with SD and none with SS. Among the tested predictors, experience of orgasm emerged as the strongest for SS (β = -.29, p < .01), followed by mood, which predicted SS and SD. Sexual and body esteem was predictive of SD only. In sexually active participants, sexual mindfulness predicted both SS (β = 0.55, p < .001) and SD (β = -0.56, p < .001) above and beyond all other variables. This study reveals unique aspects of SS and SD postinjury and supports further consideration of psychological and perceptual dimensions of SCI sexuality in rehabilitation research.

Sexual activity and function of adult men with spina bifida

OBJECTIVE

Data on sexual function of men with spina bifida (SB) is limited. We aimed to assess sexual activity and erectile dysfunction (ED) in a large international sample of men with SB.

METHODS

Men with SB (≥18yo) were recruited in an international online survey via clinics and social media. We collected data on demographics, ambulation (Hoffer classification), penile rigidity (Erection Hardness Score), sexual activity and ED (International Index of Erectile Function). Non-parametric tests were used.

RESULTS

A total of 162 men (median age 35, 62% shunted, 38% community ambulators) reported sexual desire similar to the general population (p = 0.82), but 55% were dissatisfied with their sex life (Summary Table). Overall, 36% reported full penile rigidity with erections, more commonly with better ambulation (p = 0.01), 69% had ever experienced orgasm and 84% ejaculated. In 44 men (27%) attempting sexual intercourse in the last 4 weeks, 59% had ED (11% severe, 7% moderate, 14% mild-moderate, 27% mild). In this group, 91% of men reporting less than full penile rigidity had ED, compared to 30% with full penile rigidity (p = 0.001). Overall, partnered non-genital contact in the last 3 months was reported by 56%, solo masturbation: 62%, partnered intercourse: 48% (31% vaginal). Of 54 men who used phosphodiesterase type 5 inhibitors (PDE5I), 80% reported improved erections, 56% improved intercourse. Overall, 40% reported non-genital erogenous zones as most pleasurable, especially with poorer ambulation (p = 0.002, chest/nipples: 73%).

COMMENT

Strengths of this study include anonymous, voluntary, online participation maximizing participation of a heterogenous, international population. Whenever available, we compared findings to published values for the general population. Since romantic and sexual activity is a complex intersection of interest, opportunity and ability, a more comprehensive assessment was beyond the study's scope. Future work will focus on the interplay with issues like incontinence.

CONCLUSIONS

ED was frequent among men with SB, especially in men with poorer ambulation. PDE5 inhibitors may be beneficial. Partnered sexual activity was reported by half of the men, although it may not involve penetrative intercourse.

Male Sexual Dysfunction and Infertility in Spinal Cord Injury Patients: State-of-the-Art and Future Perspectives

Spinal cord injury (SCI) is a relevant medical and social problem. According to the World Health Organization, the commonly estimated worldwide annual incidence of SCI is 40 to 80 cases per million population. After the SCI experience, most men present with sexual dysfunction (erectile dysfunction (ED) and ejaculatory dysfunction), fertility problems (such as impaired spermatogenesis, abnormalities in sperm viability, motility, and morphology), and systemic disorders such as genitourinary infection and endocrine imbalances. The best options available for managing the ejaculatory disorders in patients suffering from SCI are penile vibratory stimulation (PVS) and electroejaculation (EEJ). Furthermore, the treatment of ED in SCI patients consists of medical therapies including phosphodiesterase 5 inhibitors (PDE5i), intracavernosal injections (ICI), vacuum erection devices (VEDs), and surgical as penile prosthesis (PP). This review provides a snapshot of the current evidence for the mechanisms of sexual dysfunction and infertility in SCI patients, discusses the best management strategies for these conditions, and offers our perspective on the direction of future research.

The Lost Penis Syndrome: A New Clinical Entity in Sexual Medicine

INTRODUCTION

The "lost penis syndrome" (LPS) is a term often used in non-clinical settings to describe the subjective perception of the loss of cutaneous and proprioceptive feelings of the male organ during vaginal penetration. Although deserving clinical attention, this syndrome did not receive any consideration in the medical literature. Notwithstanding, it represents a relatively unexceptional condition among patients in sexual medicine clinics, and it is often reported together with other sexual dysfunctions, especially delayed ejaculation, anejaculation, male anorgasmia and inability to maintain a full erection.

OBJECTIVES

To draft a new conceptual characterization of the LPS, defined as a lack of penile somesthetic sensations during sexual penetration due to various causes and leading to several sexual consequences in both partners.

METHODS

Based on an extensive literature review and physiological assumptions, the mechanisms contributing to friction during penovaginal intercourse, and their correlation to LPS, have been explored, as well as other nonanatomical factors possibly contributing to the loss of penile sensations.

RESULTS

Efficient penile erection and sensitivity, optimal vaginal lubrication and trophism contribute to penovaginal friction. Whenever one of these processes does not occur, loss of penile sensation defined as LPS can occur. Sociocultural, psychopathological and age-related (ie, couplepause) factors are also implicated in the etiology. Four types of LPS emerged from the literature review: anatomical and/or functional, behavioral, psychopathological and iatrogenic. According to the subtype, a wide variety of treatments can be employed, including PDE5i, testosterone replacement therapy and vaginal cosmetic surgery, as well as targeted therapy for concomitant sexual comorbidity.

CONCLUSION

We held up the mirror on LPS as a clinically existing multifactorial entity and provided medical features and hypotheses contributing to or causing the occurrence of LPS. In the light of a sociocultural and scientific perspective, we proposed a description and categorization of this syndrome hypothesizing its usefulness in daily clinical practice. Colonnello E, Limoncin E, Ciocca G, et al. The Lost Penis Syndrome: A New Clinical Entity in Sexual Medicine. Sex Med Rev 2021;XX:XXX-XXX.