Hemipelvectomy, also known as a pelvic resection, is a surgical procedure that involves the removal of part of the

pelvic girdle The hip bone (os coxae, innominate bone, pelvic bone or coxal bone) is a large flat bone, constricted in the center and expanded above and below. In some vertebrates (including humans before puberty) it is composed of three parts: the Ilium (bone) ...

. This procedure is most commonly performed to treat oncologic conditions of the pelvis. Hemipelvectomy can be further classified as ''internal'' and ''external'' hemipelvectomy. An ''internal'' hemipelvectomy is a limb-sparing procedure where the innominate bone is resected while preserving the ipsilateral limb. An ''external'' hemipelvectomy involves the resection of the innominate bone plus

amputation Amputation is the removal of a Limb (anatomy), limb or other body part by Physical trauma, trauma, medical illness, or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as cancer, malign ...

of the ipsilateral limb.

Medical uses

Hemipelvectomy is generally reserved for the treatment of pelvic

neoplasm A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

s. Examples of malignancies that are treated with hemipelvectomy include

osteosarcoma An osteosarcoma (OS) or osteogenic sarcoma (OGS) is a cancerous tumor in a bone. Specifically, it is an aggressive malignant neoplasm that arises from primitive transformed cells of mesenchyme, mesenchymal origin (and thus a sarcoma) and that exhi ...

chondrosarcoma Chondrosarcoma is a bone sarcoma, a primary cancer composed of cells derived from transformed cells that produce cartilage. A chondrosarcoma is a member of a category of tumors of bone and soft tissue known as sarcomas. About 30% of bone sarco ...

, and Ewing's sarcoma. Rarely, hemipelvectomy is performed in settings of traumatic injury and

osteomyelitis Osteomyelitis (OM) is the infectious inflammation of bone marrow. Symptoms may include pain in a specific bone with overlying redness, fever, and weakness. The feet, spine, and hips are the most commonly involved bones in adults. The cause is ...

. Indications for ''external'' hemipelvectomy include neoplastic extension into the sciatic nerve, where loss of function of the lower extremity is anticipated. ''Internal'' hemipelvectomy is preferred when complete resection of the tumor is possible without sacrificing the lower extremity. If ''external'' hemipelvectomy cannot provide a greater degree of tumor resection compared to ''internal'' hemipelvectomy, ''internal'' hemipelvectomy is recommended. ''Internal'' hemipelvectomy must only be considered when the surgical approach can ensure the preservation of critical neurovascular structures in the region.

Complications

As with any surgical procedure, risks include infection, blood loss, damage to surrounding structures, cardiac/pulmonary complications, and adverse reactions to anesthesia. Complications of ''external'' hemipelvectomy include: * Disfigurement * Loss of ambulation * Phantom limb pain * Bladder dysfunction * Sexual dysfunction * Bowel dysfunction Complications of ''internal'' hemipelvectomy include: * Leg-length discrepancy * 'Flail hip' or 'floating hip' (referring to hypermobility of the hip joint) * Hip instability

Technique

Prior to performing a hemipelvectomy, surgeons must possess detailed knowledge of the pelvic anatomy and its relation to the pelvic tumor. Imaging studies such as conventional radiography,

computed tomography A computed tomography scan (CT scan), formerly called computed axial tomography scan (CAT scan), is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers or ...

, and

magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and ...

help the surgeon visualize the anatomy and its relationship to the local pathology. Surgical oncology techniques are utilized when resecting tumors of the pelvis. Such techniques ensure that adequate resection margins are obtained at the time of surgery to minimize tumor recurrence. The Enneking and Dunham classification system was developed in 1978 to aid surgeons in characterizing pelvic resections. This classification scheme breaks down pelvic resections into 3 subtypes: Type I, Type II, and Type III. Type I resections involve removal of the ilium. Type II resections involve removal of the peri-acetabular region. Type III resections involve removal of the ischial and/or pubic region. Resection of pelvic bone typically requires subsequent reconstruction to ensure stability of the hip joint, particularly in ''internal'' hemipelvectomy. Examples of pelvic reconstruction include the use of an

allograft Allotransplant (''allo-'' meaning "other" in Ancient Greek, Greek) is the Organ transplant, transplantation of cell (biology), cells, Biological tissue, tissues, or Organ (anatomy), organs to a recipient from a genetically non-identical donor of ...

, autograft, or

prosthesis In medicine, a prosthesis (: prostheses; from ), or a prosthetic implant, is an artificial device that replaces a missing body part, which may be lost through physical trauma, disease, or a condition present at birth (Congenital, congenital disord ...

to bridge the remaining ends of pelvic bone following resection. Arthrodesis is a technique that can be used in ''internal'' hemipelvectomy to fix the proximal

femur The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femo ...

to a segment of pelvic bone for the purposes of stabilizing the lower extremity.

Images

File:Internal Hemipelvectomy.jpg, An x-ray of a limb-sparing hemipelvectomy on the left side of a male pelvis taken one month after surgery. File:Hemipelvectomy_Male_Pelvis.jpeg, An x-ray of the same pelvis taken eighteen months after surgery highlighting the femur migration to its final resting place.

References

External links

Amputee Coalition of America

Pelvic Amputation: What is a Hemipelvectomy?
{{Muscle/soft tissue procedures Surgical oncology Surgical removal procedures Types of amputation