Hemicorporectomy

Overview
In medicine (surgery), hemicorporectomy (also named translumbar amputation and "halfectomy") is a radical surgery in which the body caudal to the waist is amputated, transecting the lumbar spine. This removes the legs, the genitalia (internal and external), urinary system, pelvic bones, anus, and rectum. It is a severely mutilating procedure recommended only as a last resort for patients with severe and potentially fatal illnesses such as osteomyelitis, tumors, severe traumas and intractable decubiti in, or around, the pelvis. It has only been reported a few dozen times in medical literature.

The nomenclature is somewhat at odds with generally accepted anatomical terms, as hemi is generally used to refer to one of two sides (e.g. hemiplegia, which affects the arm and leg on one side of the body). In that sense, paracorporectomy might more closely reflect the nature of the procedure.

History
The development of surgical medicine was vastly accelerated during, and following, the Second World War. Rarely experienced traumas were made more common by new weaponry. This required decisive surgical action as well as the development of new techniques. As B. E. Ferrara stated in his summative article on hemicorporectomy:

"lessons learned from battle field injuries quickened innovative treatment of congenital and acquired conditions... [the general surgeon] devised extensive cancer operations including extended radical mastectomy, radical gastrectomy and pacreatectomy, pelvic exenteration, the 'Commando operation' (tongue, jaw and neck dissection), bilateral back dissection, hemipelvectomy, and then hemicorporectomy or translumbar amputation, referred to as the most revolutionary of all operative procedures."

It was into this environment that Frederick E. Kredel first proposed the operation in February 1951 while discussing a paper on pelvic exenteration. The first hemicorporectomy was attempted by Charles S. Kennedy in 1960, but the patient died eleven days later. J. Bradley Aust and Karel B. Absolon conducted the first successful hemicorporectomy in Minnesota in 1961.

Indications
The operation most often results after spreading cancers of the spinal cord and pelvic bones. Other reasons may include trauma affecting the pelvic girdle ("open-book fracture"), uncontrollable abscess or ulcers of the pelvic region (causing sepsis) or other locally uncontainable conditions. It is used in cases wherein even pelvic exenteration would not remove sufficient tissue.

Procedure
The surgical procedure is often done in two stages; however it is possible to conduct the surgery in one stage. The first stage is the discontinuation of the waste functions in colostomy (rectum) and ileal conduit (bladder). The second stage is the amputation.

Considerations
With the removal of almost half of the circulatory system, cardiac function needs to be closely monitored while a new blood pressure set-point develops.

Removal of large parts of the colon can lead to loss of electrolytes. Similarly, calculated measurements of renal function (such as the Cockroft-Gault formula) are unlikely to reflect actual activity of the kidney, as these calculations were developed for patients in whom the circulatory system correlates with the body weight; this relation is lost in a post-hemicorporectomy patient.

Revalidation
Extensive physiotherapy and occupational therapy are necessary for a patient to return to some form of normal life, which invariably involves using a wheelchair. Designing a prosthesis for the removed body parts is difficult, as there is generally no remaining pelvic girdle musculature (unless this has been spared expressly).

Traumatic hemicorporectomy
Many emergency rooms have protocols under which they will not resuscitate or support a patient who has already undergone a severe bisection injury that is essentially a de facto hemicorporectomy. This stance is largely due to very limited rates of survival. A study which cased 267 blunt and penetrating trauma patients (decapitation, hemicorporectomy, etc.) who had cardiopulmonary arrest found that only 7 survived long term, only four of whom returned to their previous neurologic level. Apart from the overwhelming statistical unlikelihood of survival, operative hemicorporectomy is unlikely to be successful unless the patient has the "sufficient emotional and psychological maturity to cope" and "sufficient determination and physical strength to undergo the intensive rehabilitation".

Emergency rooms and ambulance services often release policy which prevents the resuscitation of such patients. The UK's National Health Service, for example, in its "Policy and Procedures for the Recognition of Life Extinct" describes traumatic hemicorporectomy as "unequivocally associated with death" and that such injuries should be considered "incompatible with life". The National Association of EMS Physicians (NAEMSP) and the American College of Surgeons Committee on Trauma (COT) have also released similar position statements and policy allowing on-scene personnel to determine such patients unresuscitatable.

Prosthetic
Following a hemicorporectomy, patients are fitted with a socket-type prosthetic often referred to as a bucket. Early bucket designs often presented significant pressure problems for patients, however new devices have incorporated an inflatable rubber lining composed of air pockets that evenly distributes pressure based on the patient's motions. Two openings at the front of the bucket create space for the colostomy bag and the ileal conduit.