Impact of the number of tacks on postoperative pain in laparoscopic repair of ventral hernias: do more tacks cause more pain?

BACKGROUND: The main source of postoperative pain after laparoscopic repair of ventral hernia is thought to be fixation of implanted mesh. This study aimed to analyze whether a relation exists between the number of tacks used for fixation and postoperative pain.

METHODS: To reduce the number of prognostic variables, only patients with primary umbilical hernia who underwent laparoscopic repair with double-crown mesh fixation were enrolled in this study. Two groups differing only in the manner of tacking were compared. Group 1 (n = 40), collected from previous studies, showed no specific efforts to minimize the number of tacks. Group 2 was a cohort of 40 new patients who underwent double-crown fixation using the minimal number of tacks considered to provide adequate mesh fixation. To eliminate systematic and random errors, the study analyzed only for postoperative pain. The severity of the patients' pain was assessed preoperatively and then 2, 6, and 12 weeks postoperatively using a visual analog scale (VAS) ranging from 0 to 100.

RESULTS: The mean number of tacks used differed significantly between the two groups: group 1 (45.4 ± 9.6) vs group 2 (20.4 ± 1.4) (p = 0.001). Postoperative pain differed significantly only at the 3-month postoperative assessment: group 1 VAS (5.78) vs group 2 VAS (1.80) (p = 0.002).

CONCLUSIONS: Although postoperative pain differed significantly at the 3-month follow-up assessment, both VAS scores were so low that from a clinical point of view, this difference seems irrelevant. Fewer tacks do not create less pain, nor do more tacks create more pain. This absence of a correlation between the number of tacks used and postoperative pain may indicate that pain after laparoscopic repair of at least small ventral hernias possibly is generated according to some "threshold" principle rather than according to a cumulative effect created by more points of fixation.