Comment to: The transinguinal preperitoneal techni
Comparing the modified Lichtenstein technique with the ProGrip patch, to the TIPP technique with the Polysoft patch, is interesting, since both methods are aimed at improving the patient’s comfort .
According to the results there is no difference con- cerning chronic pain between both techniques. Nevertheless, despite the randomized setting, the results of this study are debatable.
The study indeed showed that the modified Lichtenstein with Progrip resulted in more postoperative complications than the TIPP with Polysoft, including a femoral recurrence and the disastrous atrophy.
The difference in the incidence of chronic pain was not significant, but it should be emphasized that this result was obtained with a very high percentage of lost to follow-up (37.4%), which can seriously impair the validity, when in the short-term (with a good follow-up) the percentage of pain [3 was significantly less with the TIPP.
Some other published studies resulted in quite different results. A randomized clinical trial, comparing TIPP to the traditional Lichtenstein, with a 98% follow-up, showed a statistically significant difference in the incidence of chronic pain (3.5% vs 12.9%) . One can argue that the Lichtenstein was performed by suturing, which certainly can induce a higher risk of chronic pain. Nevertheless, meta-analyses comparing the sutured Lichtenstein to the self-adhesive patch concluded that the latter failed to reduce the incidence of chronic pain [3, 4].
The study protocol involved nerve identification in both procedures. In the TIPP, nerve identification is required for the ilio-inguinal nerve only, due to its close relationship to the external oblique aponeurosis, but identification of the other two branches is not recommended, since the superficial dissection is very limited and they are neither con- cerned by the dissection, nor in contact with the hernia patch. This is not negligible, since it was demonstrated that neurolysis may be a factor of chronic pain .
Despite the initial good intentions of the study, the final results may be impaired by the high percentage of lost to follow-up and, therefore, owns a certain risk of bias. Drawing the conclusion that one of the two techniques might be better than the other in daily practice, cannot be supported by these results and should be interpreted cautiously.