Persistent orchialgia after inguinal hernia repair: diagnosis, neuroanatomy, and surgical management

Chronic testicular pain (orchialgia) after inguinal hernia repair is a recognized and complex entity [1, 2]. In the postherniorrhaphy pain cohort, a subset of patients present with orchialgia as a primary complaint or a coexisting problem. This disabling post-operative complication is often incorrectly attributed to neuropathy of the genitofemoral nerve (GFN), which is commonly mistaken as the sensory nerve of the testicle. The spectrum of operations ranging from resection of the GFN to orchiectomy has been suggested for its surgical management often with limited efficacy. This is exemplified by the cohort of patients who did not improve after orchiectomy in the recently published Finnish Audit. Complicating matters is the significant overlap of inguinal, scrotal, and testicular pain as well as nociceptive versus neuropathic causes [2]. Delineating the etiology and appropriate management is a diagnostic and therapeutic challenge for hernia surgeons and urologists alike. The exact pathophysiology of testicular pain is poorly understood but, in the post-inguinal herniorrhaphy population, causes include ischemic orchitis, epididymitis, edema, infection, cord fibrosis and scarring, varicocele or hydrocele formation, torsion, referred pain from radiculitis or ureteral pathology, and entrapment or disruption of the paravasal nerve fibers or autonomic plexus within the cord [1–8]. Careful delineation of testicular pain from groin and scrotal pain is necessary to address the overlap of orchialgia with inguinodynia and scrotal pain. Additionally, the difference between nociceptive versus neuropathic testicular pain must be understood as their treatments differ significantly. Scrotal pain may be elicited by palpation of scrotum, pinching the scrotal skin, and dermatomal mapping. It is neuropathic and somatic in nature with symptoms of burning, hyper or hypoesthesia, allodynia, and radiation. Orchialgia may be elicited by compressing the testicle or epididymis and is typically a visceral sensation that is dull, aching, and constant. It may be accompanied by anatomic changes such as testicular enlargement or atrophy, epididymal swelling, and hydrocele or varicocele formation. The anterior wall of the scrotum is primarily affected in post-inguinal herniorrhaphy inguinodynia and innervated by somatic fibers of the ilioinguinal nerve (IIN), the iliohypogastric nerve (IHN), and particularly the genital branch of the genitofemoral nerve (GFN) [1–3]. The posterior surface of the scrotum is innervated by scrotal branches of the superficial perineal nerves via the perineal branch of the pudendal nerve (S1–S3). Injury to the inguinal segment of genital branch of the GFN with anterior-based approaches may arise during removal of the cremasteric layer (protects the cord structures including the genital branch and vas deferens), cord mobilization, dissection or ligation of the hernia sac, suturing of the inguinal floor, or placement of plug. Injury to the preperitoneal segment of GFN may arise from preperitoneal mesh or plug placement. With open or laparoscopic posterior-based repairs, injury to the preperitoneal segment of genital branch, femoral branch, or GFN trunk can arise during dissection of the preperitoneal plane, mesh fixation, or placement of mesh within the parietal compartment of the preperitoneal space in direct contact with an unprotected GFN. Mirilas and associates have meticulously delineated This comment refers to the article available at doi:10.1007/s10029-013-1150-3.