What does chronic pain from open inguinal hernia repair feel like and which nerves are responsible?

Chronic Pain After Open Inguinal Hernia Repair: Characteristics and Nerve Involvement

Pain Characteristics

Chronic pain after open inguinal hernia repair typically presents as persistent discomfort lasting beyond 3-6 months post-surgery, occurring in up to 39-54% of patients, with pain quality and location varying based on which specific inguinal nerve is affected. 1, 2, 3

The pain manifests in several distinct patterns:

• Burning, shooting, or aching sensations in the groin region, consistent with neuropathic pain characteristics 4, 2
• Testicular pain when the genital branch of the genitofemoral nerve is involved, often the predominant symptom 5
• Pain with light touch (allodynia) or increased painful response to normally non-painful stimuli, typical of nerve injury 4
• Pain that may radiate along nerve distributions or remain localized to specific anatomical points 1
• Exacerbation with movement or activities that increase intra-abdominal pressure 2

Nerves Responsible

Three primary nerves are implicated in chronic post-herniorrhaphy pain, with specific anatomical distributions:

Genitofemoral Nerve (Genital Branch)

• Most commonly associated with testicular pain following hernia repair 5
• Pain localizes to the scrotum and upper inner thigh 5
• Maximal tenderness typically found over the genitofemoral nerve distribution in the proximal inguinal canal 1
• Accounts for approximately 38% of chronic pain cases (5 of 13 patients in one series) 1

Ilioinguinal Nerve

• Causes pain in the inguinal region radiating to the medial thigh and genitalia 1, 6
• Pain distribution follows the nerve's anatomical course along the inguinal canal 6

Iliohypogastric Nerve

• Results in pain over the suprapubic region and lateral to the incision 6
• Less commonly implicated than the other two nerves 1

Clinical Examination Findings

Pain location on examination provides critical diagnostic information:

• Maximal tenderness over genitofemoral nerve distribution (most common finding) 1
• Tenderness at the medial end of the surgical scar (23% of cases) 1
• Point tenderness over the pubic tubercle 1
• No detectable abnormality on examination in approximately 23% of chronic pain cases, suggesting central sensitization or deep nerve involvement 1

Risk Factors and Incidence

Mesh repair significantly increases chronic pain risk compared to suture repair (17% vs 5%, p=0.004), though mesh reduces recurrence rates 1. Additional risk factors include:

• Preoperative pain presence (77% develop chronic pain vs 27% without preoperative pain) 2
• Intraoperative nerve injury significantly affects chronic pain development (p=0.001) 2
• Early postoperative pain severity predicts chronic pain development 2, 3
• Type of anesthesia used influences outcomes 2

Pathophysiology

The pain mechanism involves nerve injury, neuroma formation, or nerve entrapment in sutures or mesh material 6, 5. This creates:

• Neuropathic pain from direct nerve damage or compression 4, 2
• Central sensitization with upregulation of pain pathways over time 4
• Denervation pain similar to phantom limb pain mechanisms 4

Common pitfall: Failing to recognize that chronic pain represents true neuropathic injury rather than normal postoperative discomfort—this requires specific neuropathic pain management strategies, not simple analgesics 6, 2.