Fig. 4From: Surgical anesthesia with a combination of T12 paravertebral block and lumbar plexus, sacral plexus block for hip replacement in ankylosing spondylitis: CARE-compliant 4 case reportsUltrasonography of a 3D-printed pelvic phantom bathing in water, to mimic the greater sciatic foramen. PBI = posterior border of ischiumBack to article page