Reconstruction of Internal Hemipelvectomy Defects After Oncologic Resection

Internal hemipelvectomy is preferred to hindquarter amputation for pelvic tumor resection if a functional lower extremity can be obtained without compromising oncologic principles; multidisciplinary advances in orthopaedic and plastic surgery reconstruction have made this possible. The goals of skeletal reconstruction are restoration of pelvic and spinopelvic skeletal continuity, maintenance of limb length, and creation of a functional hip joint. The goals of soft-tissue reconstruction are stable coverage of skeletal, prosthetic, and neurovascular structures, elimination of dead space, and prevention of herniation. Pelvic resections are divided into four types: type I (ilium), type II (acetabulum), type III (ischiopubic rami), and type IV (sacrum). Type I and IV resections resulting in pelvic discontinuity are often reconstructed with vascularized bone flaps and instrumentation. Type II resections, which traditionally result in the greatest functional morbidity, are often reconstructed with hip transposition, allograft, prosthesis, and allograft-prosthetic composites. Type III resections require soft-tissue repair, sometimes with flaps and mesh, but generally no skeletal reconstruction. Extension of resection into the sacrum can result in additional skeletal instability, neurologic deficit, and soft-tissue insufficiency, necessitating a robust reconstructive strategy. Internal hemipelvectomy creates complex deficits that often require advanced multidisciplinary reconstructions to optimize outcomes and minimize complications.