Tension banding closure of laparotomies: results of an experimental study in dogs

Conventional laparotomy closure may cause ischemia, edema, and necrosis of the incisional edges, weakening of the tissue, and incisional hernia formation. Two experimental closure techniques were established to investigate laparotomy healing without suturing the incisional edges. In 24 dogs median laparotomies were closed applying two techniques following the principle of tension banding. Investigations after 3, 9, and 15 months were laparoscopy, tensiometry, light and electron microscopy and measurement of collagen fibril diameters. Incisions healed without incisional hernias with only minimal adhesion formation. At all time points the tensile strength after the bridging technique (BT) did not differ significantly from that in the control group. Mean tensile strength after BT was higher than after the onlay technique (OT) at all time points but did not reach statistical significance. After 3 months the incisions after OT were significantly weaker than the control group. At all time points fibril diameters after OT were significantly smaller than in the control group. After 3 and 9 months the fibril diameters after OT were significantly smaller than after BT. Incisions healed with little scar formation in spite of a chronic inflammatory reaction. This reaction was more pronounced after OT and made access to the fascia difficult after 3 months. Both techniques led to early postoperative seroma formation. Applying the principle of tension banding, laparotomies healed without suturing the incisional edges. The effect of foreign material on the ultrastructure of regenerating tissue in direct contact to the incisional region was demonstrated by the OT, in which chronic inflammation disturbed the adequate formation of collagen. Further development of both techniques might allow laparotomy closure according to the physiological requirements of wound healing.