Pelvic strength after major amputation of the sacrum. An exerimental study

Major sacral resections up to the level of S 1 and even higher have been performed. This has raised the question of the degree to which such operations weaken the pelvic ring. Fifteen cadaver pelves, including the fifth lumbar vertebra, were loaded to failure, five unresected, five after resection of the sacrum between S 1 and S 2, and five after resection about 1 cm below the promontory. The weakening of the pelvic ring amounted to approximately 30 per cent with the former type of resection and 50 per cent with the latter. Taking into consideration the calculated normal load on L 5 in upright standing it seems safe from this study to allow patients to stand with full weight-bearing at an early stage postoperatively after submaximal resection of the sacrum.