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Abdulkareem Aldoseri

Severe chronic pain following hernia repair is usually 58% of those experiencing pain indicated that their pain
due to ischemia or neuropathy. Ischemia induced in impaired specific activities. There was no correlation of
musculofascial tissues by a repair done under tension is the postoperative pain with the type of hernia or the method
most common cause of undue postoperative pain. In this used for repair.
situation, the sutures slowly cut through the tissues relieving These data need to be interpreted in terms of limitations
the pain but setting the stage for recurrence. The other of the study methodology. Self-reporting, especially of
major cause of ischemia-induced pain is tight closure of the severity of such a subjective matter as pain, is
either the deep or superficial inguinal ring during repair. confounded by variable perceptions of pain between
Most often, ischemia in the ring is partly due to edema patients, varying definitions of impairment, and similar
following operative dissection, and resorption of edema limitations. In essence, the severity data from this study
postoperatively leads to gradual resolution of pain; rarely are not completely reliable. And there was no evaluation
does testicular atrophy supervene. by a physician, preferably a blinded one, of the patient's
Neuropathy is widely recognized as a cause of chronic complaints. I am not trying to denigrate the study, for it
postoperative pain. It can be induced by nerve trauma during reports important data and raises important questions. But
dissection, neuroma formation after partial or complete it does not provide final answers.
transection, entrapment by sutures or by postoperative This study suggests that something in the currently
adhesions. The implantation of mesh, which induces scar employed methods of groin hernia repair is associated with
formation through increased inflammation, also has been an increase in postoperative pain, and it provides a hypothesis
suggested as a cause of neuropathic pain. 2 for future investigations. These provocative results should
stimulate additional effort and prospective clinical trials by
DISCUSSION the Danish Data Base group and others to elucidate the exact
causes in current surgical practices of postoperative groin
More than a decade ago, it was true that chronic disabling
pain was rare after hernia repair. It is also true that the pain. Could it be that the major change in the technique of
reported incidence of this problem has been increasing in hernia repair that has evolved over the most recent two
3
recent years, although the reasons for this change are not decades—the widespread use of implanted prosthetic mesh,
entirely settled. It is important to know the true incidence whether needed or not—is a cause? 5
of chronic, disabling pain after hernia repair, so that patients The overall incidence of chronic pain after herniorrhaphy
can make an informed choice of whether or not to undergo was 12% (18% in patients having open surgery [range
repair and can receive an acceptable informed consent. 0-75.5%] and 6% in patients treated laparoscopicaly [range
Generally, problems with an incidence of less than 1% are 1-16%]. The follow-up and method of pain assessment,
thought not to need specific mention in discussing with along with the study design and definition of chronic pain
patients the potential complications of an operation. varies to such a degree that these numbers should be
The report from the Danish Hernia Data Base group 4 interpreted cautiously. No final conclusion should be made
suggests that in current practice the incidence of chronic regarding the exact incidence of chronic groin pain in relation
pain, a year after groin hernia repair, may be approximately to the type of surgery.
29%. This number is unexpectedly high, and certainly will Single center trials of less than 300 patients generally
gain the attention of all surgeons who repair hernias. It is reported lower rates of chronic pain compared with larger
important to know if the incidence is truly so high, and if studies except for one study. None of the studies that used
so, to learn what causes the pain. If the incidence truly an objective pain measurement, for instance a VAS for pain
exceeds one percent then pain will need to be specifically assessment, found an incidence below 5%. A study of 400
mentioned in preoperative discussions with patients. patients found an incidence of moderate or severe pain
The Danish report is based on two questionnaires mailed of 2% after laparoscopy compared with 10% after open
1 year postoperatively to 1,443 patients having hernia repair surgery, but the follow-up rate was only 61%. A
during 2 months period in 1998. More than 80% of patients comparative study between total extraperitoneal (TEP) and
responded to each questionnaire. The first time around, open mesh herniorrhaphy using a retrospective questionnaire
patients were asked whether they had pain or not; 29% said in 560 patients showed that after a mean follow-up period
they had pain and 11% indicated that their pain was disabling of 21 months, 22.5% of laparoscopic patients had pain/
to some degree. The second questionnaire was sent to those discomfort compared with 38.3% of those treated by open
reporting pain asking about specific pain characteristics; mesh repair. 6

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