The effect of repetitive infiltrations as a part of a new multidisciplinary algorithm for chronic postoperative groin pain

Nijs Y, Peeters E, Verbeke H, Bruyninckx F, Theys T, Morlion B, Miserez M

Department Abdominal Surgery, University HospitalsGasthuisberg, Leuven, Belgium

Introduction- Chronic postoperative groin pain

• 11% to 54% of patients • Subgroup moderate to severe in 1,9% to 3%• Severe impact

• QoL/Social/ Physical/Mental/ Sexual• No standardisation

• Diagnosis/Work-up/Treatment

• Aim - Multidisciplinary standardised protocol

• Surgeons, pain therapists, neurosurgery, physical medicine

Loos et al, Chronic sequelae of common elective groin hernia repair , Hernia 2007

Material and methods Inclusion criteria

Chronic post-operative groin pain > 6 months and suggestive neuropathic pain (DN4 ≥ 4 and/or LANSS ≥ 12)

Exclusion criteria Nociceptive pain, meshoma, hernia relapse, complex pain

problems, previous surgery infra-umbilical M. rectus abdominis

EMG intake 4 Repetitive injections EMG at 3 months Multidisciplinary decision

=> Outcome

Uitsluiten centrale sensitisatie ? Intake EMG 1ste infiltratie 2de infiltratie 3de infiltratie Maand 1 2 weken 2 weken 2 weken 4de infiltratie EM Chirurgie of pijntherapie Maand 2 Maand 3 INTERVENTIE 2 weken 1 maand 2 maanden Evaluatie pijntherapie EMG EMG Maand 3 na interventie Maand 6 Maand 12 1 maand 3 maanden 6 maanden Nadien 6 maandelijkse FU tot jaar 2 met jaarlijkse controle EMG

• History• Anamnesis• Clinical

examination• Questionnaire

s

Multidisciplinary work-up EMG

Why ? Sensible nerve conduction studies not possible

Selective nerve stimulation unfeasible Inguinal region unfavorable anatomy

Severity and chronicity nerve damage Radiculopathy Carpal tunnel

Prognostic factor CRD’s ? Crampy contractions Local muscle ischaemia

How ? Blinded EMG Rest / Contraction Subcategorized

• Repetitive injections• Ultra-sound and/or nerve-

stimulation guided• Lidocaïn hydrochloride 2% 5ml• Interval 2 weeks

• 1st injection ilio-inguinal/ilio-hypogastric nerve

• 2nd injection genitofemoral nerve

3rd injection repetition of the most successful

4th injection differential epidural block or transforaminal infiltration

Central sensitisation ?

Ilioinguinal nerve

Iliohypogastricnerve

ter Meulen et al, Clin Neurol Neurosurg 2007Gucev et al, Anesth Analg 2008

Material and methods VASmax scores

Pre-injection, 30 and 60 minutes post-injection, clinical visits Individual plots VASmax post/pre ratio

Nijs et al, Long-term outcome of surgical treatment of chronic postoperative groin pain, Hernia 2013

Material and methods 10 patients

Median age 49,4 (30-72) 8 male, 2 female

Patient Sex Age Previous Surgery Hernia location Lap/OpenPrevious neurecto

my ?

Previous mesh

resection ?

1 F 27 Pfannenstiel NA Open 0 02 M 31 TAPP Right Lap 0 03 M 50 Lichtenstein Left Open 0 04 M 38 TEP Right Lap 0 15 M 53 Stoppa Bilateral Open 0 16 M 46 TEP Right Lap 0 07 M 30 Lichtenstein Right Open 0 08 V 73 Lichtenstein Right Open 0 09 M 60 Lichtenstein Right Open 0 0

10 V 59 TEP Right Lap 0 0

Results 2 patients complete pain relief Long term result After 3 injections Long-term follow-up

VASmax post/pre ratio 0 0

Mean ratio = Median ratio 0Mean FU 10,80 months (10,45 – 11,16)

VASmax post/pre 0 0

• Results 6 patients intermittent pain relief After each injection No permanent effect

VASmax post/pre 1,5 1,625 7

VASmax post/pre 1,25 1,14 0,93

Median ratio 1,37 (0,93 – 7)Mean FU 14,14 months (10,13-16,47)

Results 2 patients no pain relief Follow-up

VASmax post/pre 1,14 0,93

Median ratio = Mean ratio 1,03Mean FU 14,79 months (10,13 – 19,46)

VASmax post/pre 1,14 0,92

Conclusions

Multidisciplinary standardised protocol

Repetitive injections Small subset 20% permanent pain

relief Long-term effect 1st injection no effect => non-

responder

Preliminary results Larger prospective multi-center studies

needed

Thank You !!