Transpelvic, Hip Disarticulation Amputation: Taking Prosthetics to the Highest Level
June 2008 Issue
|Christina Skoski, MD|
The most important thing to keep in your mind is: Life goes on" Christina Skoski, MD, advises high-level amputees. She knows what she is talking about.
When Skoski was just 11 years old, she was diagnosed with a fibrosarcoma behind her left knee. Although amputation was recommended, Skoski and her parents wanted to try to save the leg. Like a malignant insect, the tumor kept returning and crawling farther up her leg. With every excision, she lost more function as the tumor took nerves, muscles, and tendons along with it.
So in 1962, she underwent a transpelvectomy (often called hemipelvectomy). What lay ahead for Skoski, who was a 15-year-old high school student at the time?
Skoski has built a rich and satisfying life as a successful anesthesiologist, a wife, and a world traveler to many exotic locales such as China, Greece, Egypt, Cambodia, and India, to name a few.
Like Skoski, many transpelvic and hip disarticulation amputees have had successful and fulfilling careers, marriages, and personal lives. However, for amputees at these high levels, successfully navigating through life is not a Sunday walk in the park. Encouragement, peer and family support, skilled medical care, and motivation are vitalas well as prosthetic care for those who choose to use a prosthesis.
What Are the Challenges?
|Brian Pinkston, CP|
To more fully appreciate the challenges, it is necessary to understand just how hard it is for hip disarticulation and transpelvic amputees to walk with a prosthesis. These amputations mean the loss of three weight bearing joints-the hip, the knee, and the ankle-definitely more difficult and complex than losing one or two, which in itself is difficult enough. "Living with a transfemoral amputation is about ten times as tough as living with a transtibial amputation, and living with a hip- or pelvic-level amputation is perhaps 100 times harder," says noted orthopedic surgeon Doug Smith, MD, in his article, "Higher Challenges: The Hip Disarticulation and Transpelvic Amputation Levels," in inMotion January/February 2005, published by the Amputee Coalition of America (ACA).
However Brian Pinkston, CP, a prosthetist at Shriners Hospital for Children, St. Louis, Missouri, says the effort to walk with a prosthesis is well worth it. "I'd like to encourage people to try it and decide for themselves," says Pinkston, who has been a transpelvic amputee since the age of ten. He encourages prosthetic use, "because you can fit better into society if you walk, even with a noticeable gait difference. The world still isn't quite prepared for wheelchair ambulation; there are still a lot of barriers, curbs, uneven terrain, etc."
He continues, "Using a prosthesis helps maintain muscle strength and tone, cardiovascular health, and a higher level of health overall. You can walk with crutches, but over a period of time crutch use can cause vascular and nerve damage in the arms and shoulders. Prosthetic use is not for everybody; it does require a lot of energy and stamina. But to help maintain an active, independent lifestyle, I would urge prosthetic use."
Transpelvectomy and hip-disarticulation amputations are among the rarest. According to the 2000 census, out of the U.S. population of 281 million people, 1.5 million are amputees, and less than 1 percent of these individuals, or approximately 10,000 people, are either hip-disarticulation or hemipelvectomy amputees, notes John Angelico, BS, OTR, CP, in an article, "Sockets for Hip-Disarticulation and Hemipelvectomy Amputees," inMotion, September/October 2001.
What this translates into is that, for this small group, prosthetic advances and overall medical care advances have been slower in coming than for other amputee populations. However, better materials and designs have been developed, going hand-in-hand with better surgical techniques, according to Kevin Carroll, MS, CP, FAAOP, vice president of prosthetics for Hanger Orthopedic Group, Bethesda, Maryland.
There are more hip disarticulation and hemipelvectomy amputees now than before, says Carroll, due to better surgical techniques. "More people undergoing pelvic-level amputations because of trauma are being saved. Previously, more would have ended up dying."
Hip disarticulation is the surgical removal of the entire lower limb at hip level, Smith explains in inMotion. In traditional hip disarticulation, the ball is separated from the socket of the hip joint. A modified version retains a small portion of the proximal femur to improve the contours of the hip disarticulation for sitting.
Transpelvic amputation is the removal of the entire lower limb, plus part of the pelvic bones. "It occurs in a skeletal zone that can include from the socket on the outside to the spinal column in the middle, the acetabulum ischium rami, ilium, and sacrum," Smith explains.
Even medical professionals can have a common misconception, Smith notes in the article: they assume the difference between a hip disarticulation and a transpelvic amputation is comparable to the difference between and knee disarticulation and tranfemoral amputation, and that by moving up to the next higher level of amputation there will be much more soft tissue for wound closure and padding. However, the transpelvic level generally occurs just two inches above the hip-disarticulation level. So if there is insufficient soft tissue at the hip-disarticulation level, there is not going to be significant improvement in available soft tissue at the higher level.
These high-level amputations, by starting to involve the core of the body, not just a limb, carry unique physical and emotional impact. "They have an increased impact on self-image," says Smith. "There's increased worry and stress as these surgeries start encroaching on that personal area involved in central body functions and gender identity. Although not generally the case, sometimes the surgery can affect bowel, bladder, or sexual functions."
More communication between surgeons and prosthetists is helping to provide better prosthetic outcomes, says Carroll. "More than ever before, surgeons pick up the phone and communicate directly with the prosthetist. If the prosthetist is involved upfront, we can be involved with what kind of residual limb is going to be left. This type of communication provides superior results for the patient."
Hip disarticulation and transpelvectomy surgeries frequently require more variability at the amputation site than other lower-limb amputations, Smith points out, adding, "Ingenuity and creativity may be demanded of the surgeon because the amount of tissue lost to injury, disease, or infection is different in every case." Also there is not as much soft tissue to work with for wound closure and padding as there is in lower-level amputations.
This variation challenges the ingenuity and creativity of the prosthetist as well. "Every patient has different surgical results and different needs, so prosthetists need to be very creative in their approach" Carroll says. "There are so many variables that the prosthetist has to consider. Just because one particular approach has worked for me doesn't mean it will work for everyone."
With the caveat that no one modality is necessarily right for everyone, Carroll describes his approach.
If there is enough soft tissue, Carroll uses a socket deep enough to encompass the tissue, with a clutch lock and sticky gel liner. A power belt is attached to the socket, locking everything into place, with the ischium contained in the socket. "This is a good functional prosthesis which is very comfortable because you don't have this big bucket wrapped around your body. It's also very solid because we've elongated the tissue into the socket." The patient is also taught how to fire the muscles to create strong, healthy residual limb tissues.
However, if the patient doesn't have enough soft tissue left for this approach, Plan B is to provide a well-fitted traditional hip-disarticulation socket with special care given to the floor of the socket. Since this is the piece upon which the person is sitting and standing, it has to be solid, strong, and well-fitted. Any movement in the socket when the person stands can create a feeling of instability and fear of falling.
If the person has strong, healthy tissues, the proximal trim lines can be lower, says Carroll. If the tissues are not sufficiently strong, the proximal rigid trim can go midway up toward the iliac crest, but over the iliac crest the material can become flexible for comfort.
Previously, components were generally placed underneath the tuberosity, creating a situation where patients were sitting on the components and the pelvis wasn't level as they sat, causing back pain, Carroll notes. "The closer the person's tuberosity bone is to the sitting surface, the more anatomically correct the socket is for sitting." Positioning the components lateral to the tuberosity bone and more proximal provides a more anatomically correct position for the entire hip joint and the pylon that goes from hip to knee. "With a longer pylon from hip to knee, you have a more anatomically correct placement of the knee joint," Carroll adds.
If the floor of the socket is at an incorrect angle, the person will slip off that seated area and the proximal aspects of the socket will be hitting the rib cage, raising the danger of rib fractures in female patients with osteoporosis, Carroll warns. The softer the patient's tissue, the higher the socket has to be for control; however, using flexible material in the proximal aspects helps to protect the rib cage.
In transpelvectomy patients, the tuberosity is gone; generally, the patient is left with the sacrum. Carroll advises prosthetists to view an X-ray of the patient's pelvis to see what is actually remaining. Sometimes the ilium, a part of the tuberosity, or part of the symphysis pubis bone is left. If part of the tuberosity remains, it provides a good weight bearing area that can be contained in the socket and considerably aid the patient in prosthetic use. "Communication between the prosthetist and surgeon is critical in cases like this; for instance, in cancer situations, there's time for planning," he says.
Carroll advises keeping the prosthesis simple. "I've found that the more there is on the socket, the more likely the patient is to reject it; the simpler the socket, the greater the acceptance. It's easier to use; there's less hassle in donning and doffing."
When people want to relax at home and take the socket off, Carroll explains that transpelvic amputees should use a sitting prosthesis for balance and to protect the pelvis while sitting. The socket should be constructed to make the hips look more normal and anatomically correct.
With the use of hip disarticulation and transpelvectomy prostheses, some sensitive but essential "how-to's" need to be addressed, such as toileting. A male prosthetist may ask a qualified woman on his staff to discuss these concerns with his female patients.
Other Approaches to Prosthetic Design
Pinkston has designed his own prosthesis. Pinkston's interest in the prosthetic field was stimulated by the time he spent in his youth having his own prosthetic care delivered. "I had been using the old Canadian-style bucket for years [a prosthetic design developed by Canadian researcher Colin McLaurin in 1954, with variations by others-a major improvement over previous designs]. My scoliosis was progressing, and it was j ust not working for me anymore." Transpelvic amputees tend to tilt to one side since they don't have the bony structure to sit levelly. This tilt can cause scoliosis, especially for those who underwent amputations at a young age before the skeletal structures were mature."
Pinkston decided to change from the typical laminated socket to a flexible inner socket with a rigid exterior, going higher to control the scoliosis progression. He also later switched to a more durable knee.
Although Pinkston says his prosthesis is rather unattractive-"I'm more interested in function than cosmesis"-it has worked well for him. He dons his prosthesis when he arises in the morning and doffs it when he goes to bed at night. For a prosthetist, Pinkston advises putting comfort at the top of the list. For prosthesis wearers, he urges developing stamina and balance.
Erik Schaffer, CP, president of A Step Ahead Prosthetics and Orthotics, Hicksville, New York, has designed a hip-disarticulation prosthesis which, in a sense, "locks" the prosthesis onto the person on three planes-coronal, sagittal, and transverse-providing a highly intimate fit, Schaffer explains. The socket consists of two parts: an ultralight frame and a flexible inner socket. "We use custom-formulated very high temperature plastic, proprietary to our facility, and a custom weave of carbon graphite. With these materials, we've been able to provide an innovative design in controlling the flexibility and stability in the prosthetic socket for hip disarticulation and hemipelvectomy amputees," Schaffer says.
Schaffer stresses the importance of the socket design: "Ninety-nine percent of the prosthetic control comes from the socket. If we provide intimacy of fit, control of the prosthesis, and biomechanical function, then we can start having fun as prosthetists, adding the components-the knees, the hip joints, etc."
Says Skoski, "I've seen many changes since my first primitive wooden leg, both in components and materials." Like Pinkston's, her current socket is a double-layer design, with carbon fiber rigid support on the outside and a more flexible, comfortable bioplastic inner material. Trim lines are high in order to slow any progression of her scoliosis.
Although Skoski is intrigued by the new computerized, hightech knees and might try one some day, she really likes her present prosthesis and doesn't want to change. For instance, using her 25-year-old locking hip joint, releasing the lock when she wants to sit, has become automatic. "It gives me a great deal of security. I don't have to worry about the leg extending too far." She adds, "Many of us who have been amputees for a long time, when we get adjusted to a prosthesis and are happy with it, we don't want to give it up. We hate changing to a new one."
Skoski now uses a pelvic leveler when she sits after doffing her prosthesis. Earlier as an amputee, a sitting socket or pelvic leveler wasn't recommended, possibly, Skoski says, because the materials weren't available.
Skoski, who maintains an informational website, www.hphdhelp.org , for transpelvic and hip-disarticulation amputees, has been very happy with her prosthetic care over the years. She especially appreciates the patience of prosthetists who keep trying to achieve a good, comfortable, functional fit, even if it takes several attempts.
And for other high-level amputees, she points out, "We've lost a leg, not our brains. Just do the best with what you've got."
Miki Fairley is a contributing editor for The O&P EDGE and a freelance writer based in southwest Colorado. She can be contacted via e-mail at