Etude épidémiologique Multicentrique Des Douleurs Neuropathiques Post-opératoires

Neuropathic post-surgical pain (NPSP) motivates the consultation of the French Centres for Evaluation and Treatment of Pain in 20 to 35% of the cases. The following table shows the available data of literature about chronic post-surgical pain:

Surgery Prevalence of chronic pain (%) Neuropathic symptoms Mastectomy 22 to 49 Yes Inguinal hernia repair 30 to 63 Yes Sternotomy 28 to 40 Unknown Saphenectomy 5 to 7 Yes Mandibular osteotomy Unknown Yes Cholecystectomy 3 to 20 Unknown Caesarean section 6 Unknown Thoracotomy 50 to 75 Yes Knee arthroscopy Unknown Unknown Rectal amputation 12 to 18 Unknown Limb amputation 60 Yes Endodontic treatment 5 to 13 Unknown

In most of these cases, the mechanism of pain is highly suspected as neuropathic, although the location of the nerve(s) concerned is unclear. However, the clinical features of the pain are often poorly described. In other types of surgery (such as caesarean section or cholecystectomy), the report of chronic pain may be related to the high frequency of these procedures.

The initiation of NPSP can be identified on a time scale (i.e. day of surgery), and can be prospectively expected. This leads to possibility of (i) a better understanding of the evolution of neuropathy following time and (ii) a study of putative preventive (peritraumatic) treatments. Thus, NPSP appears as strongly different from other chronic pain syndromes (such as diabetes mellitus, chemotherapy for cancer or even post-traumatic) for which the time course, mechanisms and psychic interactions are more complex.

We suspect that overall prevalence of NPSP may have been underestimated, as (i) the delay of onset of pain may be in a range between some days to several months, (ii) there is not always a systematic follow-up after most of the surgical procedures, and patients may stay out of the medical network and (iii) the benefit provided by the surgical procedure may lead to patient not to complain from a somewhat "necessary" complication.