Traditionally, in the era when recurrence was our main concern, chronic postoperative inguinal pain had been referred to using the general term “inguinodynia” for all possible types of inguinal pain manifestations. However, the variation of clinical presentations and etiologies necessitates that we broaden and deepen our understanding of this complex condition [16]. Primarily, it is important to establish the origin of the pain and to classify the location and type of pain that we are dealing with: neuropathic (follows the pattern of a dermatome of specific nerve trunks), nociceptive (non-neuropathic), or paresthesias (denervation or discomfort due to incidental or therapeutic neurectomy).

We reported the original Dermatome Mapping Classification in 2009 [9]; the updated 2015 DMC is presented in (Fig. 21.12) with respect to the pre- and postoperative evaluations of patients with chronic postoperative pain. Currently, we are updating the DMC regularly, expanding it, for example, not only to evaluate the inguinal region but also to consider thoracic nerves for cases when postoperative pain occurs in the abdominal region due to injury or entrapment of thoracic nerves during an inguinal laparoscopic surgery, or when using transfascial sutures, for instance, in the Rives or laparoscopic techniques. We have also modified the DMC to include Dr Chen’s contribution of the term “vague” for nonspecific situations, subjective inconsistencies, or patients simulating pain that had previously been termed “faking.”