Neuralgias

QUESTION 1

• 39 y.o. male s/p bilateral inguinal hernia repair presents with pain across the lower abdomen upon sitting and bending. He has no pain while standing or supine.

QUESTION 2

• 49 y.o. male 1 year s/p Lichtenstein repair of left inguinal hernia presents with a constant dull, aching pain in the groin. He also complains of severe burning with ejaculation. Eight months earlier the area was explored. No hernia was identified. The ilioinguinal nerve was divided.

QUESTION 2 -continued

• This procedure provided little relief. Physical exam, ultrasound, and CT scan did not reveal a recurrence. The vas is slightly tender to palpation. Sensation to pinprick is present bilaterally. The most likely cause of this pain is…? What would you do?

QUESTION 3

• 4 weeks s/p tension-free mesh repair of an indirect left inguinal hernia a 40 y.o. male complains of continuing severe pain that has not improved since the OR. There is point tenderness medial to the incision. Pain radiates to the base of the penis with activity. What is the likely diagnosis? What is the treatment?

NEURALGIAS AFTER HERNIA REPAIR

George S. Ferzli, MD, FACS

OUTLINE

• ANATOMY

• ETIOLOGY

• DIAGNOSIS

• TREATMENT

NEUROANATOMY

• Sensory innervations from the 12th thoracic nerve and ventral branches of the first and second lumbar spinal nerves– Iliohypogastric n.

– Ilioinguinal n.

– Genitofemoral nerve• Femoral n.

• Genital n.

Other Nerves in Proximity

• Lateral femoral cutaneous nerve

• Obturator nerve

• Femoral nerve

ANTERIOR VIEW

PREPERITONEAL VIEW

Sensory Innervation

• Peripheral communication between the ilioinguinal, iliohypogastric and genital branch of the genitofemoral nerves is very common and results in an overlap of their sensory innervations

• Innervation fields of the three nerves overlap

• Central overlap also exists due to common nerve route origin

• More than one nerve can cause post herniorraphy pain

EtiologyAmid, P, Arch. Surg. 137, 100-104,Jan 2002

• Non- neuropathic pain

• Neuropathic pain

Non-neuropathic Pain

• Secondary to excessive scar formation

• Periosteal reaction (sutures/staples in pubic tubercle)

• Mechanical pressure from bulky or rolled-up mesh

Neuropathic pain

• Perineural fibrosis (not nerve entrapment)

Neuropathic Pain

• Entrapment by staples (a) or sutures (b)

Neuropathic Pain

• Entrapment by prosthetic material

Neuropathic Pain

• Neuroma

CAUSES FOR NERVE INJURY

• Inadequate or excessive dissection

• Failure to visualize and protect the nerves

• Failure to recognize aberrant location and anatomic variation of nerves

DIAGNOSIS

• Most postoperative neuralgias will begin to disappear within several weeks of operation

• If symptoms > 2 or 3 months, investigation is indicated

• GF vs. II/IH ( both can cause symptoms to inner thigh and scrotum

• History/Physical– Triggered or aggravated by

walking, stooping or hyperextension of the hip

– Decreased by Recumbence and flexion of the thigh

– Tinel sign- Pain reproduced by tapping skin medial to the anteriosuperior iliac spine

Four Step ProtocolLichtenstein and Amid

Am. J. of Surgery 155, 786-790,1998

1. Ilioinguinal Nerve Block

• 10 ml of 0.25% bupivicaine – If pain improves but recurs may repeat and resection of the

ilioinguinal nerve may be indicated

2. Genitofemoral Nerve Block

• Anesthesiologist/fluroscopy

• 10 ml of 0.25% bupivicaine injected at first and second lumbar level

• If pain relief is significant but recurs in 24 hours than interruption of the genitofemoral nerve is indicated

3. NSAID Trial

• If neither block is effective than a trial of NSAIDS (Sulidac or Ibuprofen)

4. Alternative Therapy

• Biofeedback,hypnosis,pain clinics and psychotherapy

TREATMENT

• TWO NERVE EXCISION– Excise ilioinguinal and iliohypogastric nerves

via an anterior inguinal approach– If pain not relieved, perform a genitofemoral

nerve excision via a transverse flank incision

(Starling, Lichenstein and Nyhus)

TREATMENT

• One stage surgical treatment– Triple neurectomy

with proximal end implantation without cord mobilization

Amid,P Arch Surg 137,100-104, Jan 2002

TREATMENTKrahenbuhl et al, Br. J. of Surg. 1997, 84, 216-219

• Retroperitoneal endoscopic neurectomy for nerve entrapment after hernia repair– GF nerve with its two branches

can easily be identified as it penetrates medially the psoas muscle 4-5 cm with the bifurcation included

– II/IH nerves can be exposed and resected proximal and lateral to the GF nerve where it crosses the quadratus lumborum muscle