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Background and Aims Delivering local anesthetics into the obturator canal is pivotal to guarantee obturator nerve blockade because all obturator nerve divisions invariably run through it. However, local anesthetic injections in the subpectineal plane (i.e., ultrasound-guided proximal obturator nerve block techniques) may not spread to the obturator canal. We devised an ultrasound-guided technique for delivering a local anesthetic directly into the obturator canal. This cadaveric study investigated the spread of the injectates using our method.Methods This study was approved by the institutional ethics committee (approval number: 2024288). Six legs from four Thiel-embalmed cadavers were used. The cadavers were placed supine with the hips flexed and externally rotated. A linear ultrasound transducer was placed on the genitofemoral sulcus to observe the external orifice of the obturator canal immediately posterior to the inferior margin of the superior pubic ramus. A needle tip was positioned at the distal end of the obturator canal solely under ultrasound guidance to inject 5 mL of dye.Results The presence of dye in the pelvic cavity through the obturator canal was confirmed in all specimens. The superior fascicle of the obturator externus muscle was tightly attached to the superior pubic ramus in two legs, covering the opening of the obturator canal ( figure 1). The subpectineal plane appeared non-contiguous with the obturator canal in these specimens.Conclusions Our approach can deliver even a 5 mL solution into the obturator canal. This may be helpful, especially in cases where the subpectineal plane is not open to the external orifice of the obturator canal.Abstract EP058 Figure 1Spread of blue dye (5 ml) in a cadaveric specimen after right-sided ultrasound-guided obturator canal approach for obturator nerve block