BACKGROUND The anatomic region on the lateral cortex of the ileum, where a palpable groove is formed by angulations of the lateral cortex of the iliac wing, is recommended as the insertion point for the pelvic emergency clamp by many authors. In our opinion this technique often leads to an incomplete closure of the anterior pelvic ring as well as to bacterial contamination of the access for the sacroiliac joint screw fixation and is accompanied by a risk for nerve and vessel injuries. To reduce these risks the pelvic clamp was placed at a supra-acetabular location. The goal of our study was to report on our experiences with the supra-acetabular position of the pelvic emergency clamp and to compare our results with the current literature. METHODS From September 1998 to February 2006 the pelvic emergency clamp was applied in 15 polytraumatized patients (9 male, 6 female), with a mean age of 46 years (19-93) and a mean injury severity score (ISS) of 40 points (25-66) with mechanically and hemodynamically unstable pelvic ring fractures. According to the AO classification the injury pattern was type B2 in four cases, type B3 in one case, type C1 in seven cases, type C2 in two cases and type C3 in one case. The pelvic clamp was percutaneously applied 2-3 cm cranial to the acetabular roof. The duration from hospital admission until the pelvic emergency clamp was applied amounted to an average of 54 min (15-150); the procedure itself was performed in all cases in less than 15 min. The mean Hb at arrival in the emergency department was 7.4 (2.4-13.8) mg/dl and the mean systolic blood pressure 69 (0-130) mmHg. RESULTS In 14 patients a complete closure of the anterior and posterior pelvic ring could be achieved; in 1 patient an overcompression of the anterior pelvic ring was observed. Four patients died due to massive bleeding. Three patients with isolated pelvic ring fractures became hemodynamically stable within 20 min after treatment with the supra-acetabular pelvic clamp. Nine patients needed additional emergency surgery because of intracerebral, intrathoracic or intra-abdominal injuries. On average in the first 6 h, 36.7 (9-175) units of erythrocyte concentrates and 34.5 (4-200) units of fresh frozen plasma were transfused. CONCLUSIONS The supra-acetabular pelvic clamp leads to a homogeneous force distribution to the pelvic ring and enables complete closure of the anterior and posterior pelvic ring in unstable pelvic fractures. Reduction of the intrapelvic volume and compression of the posterior pelvic ring can thus be achieved. Risks for intrapelvic perforation or injuries of vessels and nerves are low. No bacterial contamination of the access for the sacroiliac screw fixation occurs. To avoid overcompression of the unstable pelvic ring, manual or radiological control of the closure of the ventral pelvic ring is necessary.