The objective was to assess the efficacy of dural tenting sutures as a prophylactic measure against extradural haemorrhage following craniotomy. A comparison was made of postoperative extradural haemorrhage between a surgeon always using tenting sutures and a surgeon who never uses them. The subjects consisted of 130 adult patients, 44 with postoperative scans, with normal blood coagulation who underwent elective supratentorial craniotomy (September 1998 to December 2000). Outcome measures were haematoma volume and midline shift as measured on CT and reoperation due to extradural haematoma. The group using tenting sutures had larger median extradural haematoma (2.5 vs 2.0 ml) and midline shift (3 vs 0 mm) than the omitting group. These differences were not significant (P = 0.74 and 0.84). Reoperation due to extradural haemorrhage occurred in 3.6% of the group using tenting sutures and in 0% of the group omitting them. Prophylactic dural tenting sutures do not reduce the size of extradural haematomas in this study. A prospective, randomized trial is needed to eliminate surgeon bias.