What is Pudendal Neuralgia?
Pudendal neuralgia is a painful, neuropathic condition involving the dermatome of the pudendal nerve. This condition is not widely known and often unrecognized by many practitioners. The International Pudendal Neuropathy Association (tipna.org) estimates the incidence of this condition to be 1/100 000 of the general population. Spinosa et al. document the incidence at 1% in the general population, affecting women more than men (Hibner et al. 2010).
Pudendal nerve entrapment has been described to manifest itself symptomatically in a number of debilitating manners; therefore a clear understanding of the nerve anatomy and distribution is essential in diagnosis. The pudendal nerve carries motor, sensory, and autonomic fibers; subsequently, both afferent and efferent pathways are affected by its injury (Hibner et al. 2010).
The Anatomy of the Pudendal Nerve
The distribution of the pudendal nerve, in the perineum, is mediated by 3 branches derived from the sacral roots S2-S4. These branches are the dorsal nerve of the penis or clitoris, the perineal nerve, and the inferior anal nerve. On the basis of this pattern of distribution, damage to the pudendal nerve can result in either unilateral or bilateral pain in the female vulva, vagina, or clitoris, or, correspondingly, the male scrotum, testes, or penis (Hibner et al. 2010).
Pudendal Nerve Dysfunction
Dysfunction of the pudendal nerve, caused by entrapment or compression, is therefore not only suspect, in generating this chronic, debilitating pain but also likely to negatively alter the interaction between pelvic organs and the afferent, efferent, and autonomic signals, which mediate their proper function (Hibner et al. 2010).
Symptoms of Pudendal Neuralgia
Pudendal neuralgia is defined as a burning neuropathic pain in the distribution of the pudendal nerve, as described above. In brief, the pain is localized to the vulva, vagina, clitoris, perineum, and rectum in females and to the glans penis, scrotum excluding testicles, perineum, and rectum in males (Hibner et al. 2010).
.In those cases, it may present as vague, neuropathic pain in the area of the lower abdomen, posterior thigh, or even the lower back and can be attributed to muscle spasm. Patients with pudendal neuralgia often have associated symptoms such as urinary frequency and urgency, symptoms mimicking interstitial cystitis, dyspareunia, and persistent sexual arousal. The pain, as in other cases of neuropathic pain, is burning, tingling, and numbing in nature. Patients have significant hyperalgesia (increased sensitivity and significant pain to mild painful stimulus), allodynia (pain in response to nonpainful stimulus), and paresthesias (sensation of tingling, pricking, or numbness, commonly known as ‘‘pins and needles’’) (Hibner et al. 2010).
Typically, symptoms are present when patients are sitting down and are much less severe or may even be absent when lying down or standing. Anecdotally, there is significantly less pain when sitting on a toilet seat versus a chair. This phenomenon is believed to be associated with pressure applied to the ischial tuberosities rather than to the pelvic floor muscles. Patients usually awaken in the morning with minimal or no symptoms; however, the pain will increase as the day progresses. Often, patients will report the sensation of having a foreign body in the vagina or feeling as though they are sitting on an object, such as a tennis ball (Hibner et al. 2010).
Causes of Pudendal Neuralgia
Pudendal neuralgia can be caused by mechanical injury to the nerve, viral infection, or immunologic processes. In the case of mechanical injury to the nerve, most practitioners will refer to the condition as pudendal nerve entrapment. This ‘‘entrapment’’ may be caused by pelvic floor muscle spasm (levator ani or obturator internus), pressure from surrounding ligaments (sacrospinous, sacrotuberous), or scar tissue from trauma or surgeries involving the surrounding areas. In patients who have undergone surgery, entrapment may be caused by mesh or suture directly injuring the nerve (Hibner et al. 2010).
In women, the 3 most common causes of pudendal nerve entrapment are surgical injury, pelvic trauma, and childbirth. In our practice most of our female patients present with pudendal neuralgia as a result of previous gynecologic surgery, particularly vaginal surgery for prolapse or incontinence. The second most common presentation, in female patients, is a history of previous pelvic trauma, such as heavy lifting, falls injuring the back or buttocks, as well as patients inserting foreign objects rectally. The least common manifestation is pudendalnerve neuralgia caused by vaginal childbirth in females. Pelvic trauma, on the other hand, is responsible for the greatest cohort of pudendal neuralgia cases in males (Hibner et al. 2010).
Treatment of Pudendal Neuralgia
The osteopath need to address the pelvic floor muscle dysfunction. The osteopath addresses muscle imbalances, spasm, restricted tissues, and other dysfunctions by focusing on palpation and manual techniques, posture, range of motion, and strength of the pelvis, back, and hips. Therapy is administered in the form of ‘‘hands-on’’ techniques, exercises, stretching, and education (Hibner et al. 2010).
Most of these patients have significant muscle spasm and subsequent muscle shortening throughout the pelvic girdle. Osteopaths use a variety of manual techniques to help release the muscle spasms and lengthen these muscles. These methods include myofascial release, soft tissue and connective tissue mobilization, and trigger point release. The pelvic floor muscles can only be fully examined and treated with either intravaginal or intrarectal approaches and to the level of patient tolerance (Hibner et al. 2010).
Hibner M, Desai N, Robertson LJ, Nour M (2010). Pudendal Neuralgia. J Minim Invasive Gynecol. Mar-Apr;17(2):148-53