Page 84 - International guidelines for groin hernia management

Hernia

neuropathic pain. Only three studies have examined the landmark) can be made. However, multiple authorities
effect of local anesthesia on chronic pain. 241–243 consider that nerve blocks serve an important diagnostic
The most notable of these is a small double-blind RCT function and can be effective in the treatment of CPIP.
demonstrating that ultrasound-guided IIN and IHN blocks Cryoablation has been the subject of a few case reports
did not produce pain relief. 241 It is not clear from the study involving few patients and limited follow-up. The initial
what percentage of patients had improperly placed nerve positive results should be viewed accordingly.
blocks despite ultrasound guidance. All available studies on neuromodulation for CPIP cite
A larger uncontrolled, retrospective study of 43 patients sustained pain relief, quality-of-life improvement, and/or
used local anesthetic and a corticosteroid injection with analgesic use reduction or cessation. However, these
nerve stimulator or ultrasound guidance. Thirty-two per- studies have significant limitations, such as retrospective
cent of the patients were relieved of moderate-to-severe design, case report or series design, lack of control group,
pain and nerve blocks, done as described, were considered short follow-up time, and no report of adverse events or
to be an effective treatment modality. 242 complications. Presently, there is weak preliminary infor-
A case series describes CT-guided GFN block as an mation in support of neuromodulation to treat CPIP.
effective diagnostic and therapeutic option. 243
Neuroablative techniques for chronic pain relief have Key question
been described. 244–253 Cryoablation for chronic inguinal
pain has been the subject of two case studies involving a KQ19T.e Is mesh removal without intentional neurectomy
244, 249
total of ten patients. One of these studies reported a an effective treatment for chronic pain after IH repair?

77.5% mean overall pain reduction with an average follow- Evidence in literature
244
up period of 8 months. Another successful cryoablation Mesh removal can be considered if nociceptive pain due to
case involved a patient with chronic inguinal pain but no mesh occurs. Compression of adjacent structures like the
249
prior hernia surgery. spermatic cord and surrounding inflammation is thought to
The effects of peripheral nerve stimulation (PNS), dorsal be the mechanism of this pain. Often mesh is wrinkled and
root ganglion stimulation (DRGS), and spinal cord stimu- fibrotic causing pain in certain positions like sitting.
lation (SCS) on CPIP are new to the pain management However, some patients have pain that is both nociceptive
field. Our literature search of PubMed and Embase yielded and neuropathic. 256 Therefore, the effect of mesh removal
117 articles using the terms ‘‘inguinal pain posthernior- without neurectomy is difficult to interpret.
rhaphy.’’ Excluding transcutaneous electrical nerve stimu- After a literature search, we identified 120 papers and
lation studies left 11 articles involving 64 patients considered nine to be suitable/eligible for inclusion in our
undergoing PNS, SCS, or DRGS. The largest of these review/discussion. 205, 257–264 In total, 278 operations for
involved DRGS and pain relief of 76.8 ± 8.2% (n = 10) mesh removal were included. Five studies were retro-
with a follow-up period of 17.4 ± 5.7 weeks. 254 Another spective case series. 257–259, 261, 263 Efficacy rates in sig-
small study with a follow-up period of 12 months reported nificantly reducing or eliminating pain ranged from 60 to
pain relief of [ 75% and reduced pain medication intake 100%. Data on the effect of mesh removal alone cannot
with SCS. 255 The other articles in this subject area are case easily be extracted, since the majority combined mesh
reports or small case series. removal with a tailored or triple neurectomy (82%).
Iatrogenic nerve injury during mesh removal was often an
Discussion indication for simultaneous neurectomy. However, Cam-
Few studies exist on nerve blocks for CPIP; therefore, no panelli et al. routinely performed a neurectomy. 263
evidence-based recommendations for preferred technique
(ultrasound-guided, neuro-stimulator directed, anatomic

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