Spinopelvic tumor resection and reconstruction.

How are spinopelvic tumor resections classified? The type of pelvic resection depends on the area involved and the extent of the tumor. Problems arise when the tumor involves the sacrum and the lower lumbar spine. To obtain acceptable surgical margins in these cases, skeletal resection should extend beyond the standard hemipelvectomy (ie, the sacroiliac joint) and may include the ilium, part of or the entire sacrum, and part of the lower spine. Major spinopelvic resections have been classified into 4 types: type 1, total sacrectomy with or without lumbar vertebra resection and bilateral iliac wing resection; type 2, total hemisacrectomy with or without lumbar hemivertebrectomy and unilateral medial ilium resection; type 3, hemisacrectomy, lumbar hemivertebrectomy with or without lumbar hemivertebrectomy, and external hemipelvectomy; and type 4, total sacrectomy with or without lumbar vertebrectomy, medial ilium resection on retained side, and external hemipelvectomy.1