Limb Replacement Through Osseointegration (OI) Gives Persons with Amputations Control of Their Lives

For patients who face amputations, the road to recovery is a long one, filled with physical, emotional and social challenges. For those who undergo bilateral transfemoral amputations, the impact of limb loss is amplified.

In 2014, real-estate attorney Alex Weatherford was in his early 30s and enjoying time with his wife and 18-month-old twin daughters. He remembers regaining consciousness at Memorial Hermann-Texas Medical Center two weeks after a surviving the crash of a two-seater plane in Shepherd, Texas, an hour north of Houston.

The pilot, a friend of a friend, was flying him to look at a property in the area. He buzzed a private landing strip to announce that they planned to land; however, the plane malfunctioned and went down in the surrounding trees. The entire front of Weatherford’s body absorbed the impact, and his legs were crushed.

“I had lost a lot of blood, and I remember the trauma and orthopedic teams discussing how to move forward with my care,” he says. “My wife, Nicola Dundas, a pathologist, was there. I was in bad shape but had no internal bleeding. I was losing all the blood through my legs. They told us they'd like to remove my legs above the knee, and with the support of my wife, I decided to move forward with amputation.”

Weatherford was discharged a month after the accident, and he began a home rehabilitation program with physical and occupational therapy. “I’ve always been athletic, so I didn’t really require home therapy and started outpatient therapy instead at TIRR Memorial Hermann Outpatient Rehabilitation – Kirby Glen Center three times a week. My therapists’ ultimate goal was to have me fitted with prosthetic legs and teach me to start using them. You go through a lot before you get the prosthetics. During this time, I was building strength, learning to sit up properly in a wheelchair and seeing prosthetists.

“First, I was fitted with short prosthetics a few inches off the ground and worked on increasing my ability to bear weight,” Weatherford says. “The carbon fiber shells that fit over your legs are big and bulky. They’re hot on the skin and when you sweat, they lose suction and come off. I tried for a year and a half with the prostheses, but they weren’t for me, so I decided to use a wheelchair.”

At the time, his rehabilitation plan was overseen by Danielle Melton, MD, former director of the Amputee and Limb Loss Rehabilitation Program at TIRR Memorial Hermann. “Early in January 2021, Dr. Melton told me OI had been approved by the FDA in the United States,” Weatherford says.

Coping with Limb Loss

Physiatrist Vinay Vanodia, MD, assistant professor of physical medicine and rehabilitation at McGovern Medical School at UTHealth Houston and the new director of the Amputee and Limb Loss Rehabilitation Program at TIRR Memorial Hermann, trained under Dr. Melton as a fellow in orthopedic trauma and amputee rehabilitation at UTHealth Houston in 2020 through 2021. When he took over as director, he had the advantage of familiarity with the patients and the OI procedure, as well as extensive experience with the specialized rehabilitation protocol. Prior to medical school, Dr. Vanodia worked as a board-certified prosthetist, making prosthetic legs for the amputee population.

“Limb-loss patients have to deal with the physical, functional and cosmetic components of losing a limb, and at the same time they’re learning how to cope psychologically with the limb loss,” says Dr. Vanodia. “Many do well in the hospital, where they receive assistance with the activities of daily living, but for some, returning home, where they previously were independent, can be difficult. That’s where support from family, friends, the health care team and support groups comes into play.”

The power to move from sitting to standing comes from muscles that pass over the knee joint. Persons with unilateral transfemoral amputations have to be able to power themselves from a sitting position to standing with their sound leg to be candidates for a prosthesis. Those who can accomplish this begin therapy with the goal of developing the strength they need to use a traditional prosthesis which has a socket to hold the limb.

“In the first few months after amputation, patients tend to lose a lot of volume in the leg, causing the leg to drop too far into the socket,” Dr. Vanodia says. “This creates pressure and discomfort and can lead to skin breakdown. People want to be able to walk, but many discover they can’t. With bilateral transfemoral amputations like Alex’s, you have to push yourself up into a standing position, and then you have two sockets pushing on your groin. People tend to walk a bit and then take them off. With bilateral limb loss, wheelchair use increases significantly.”

OI emerged as an attempt to overcome the issues associated with traditional socket-mounted prosthetics. It eliminates the need for a socket, which is the most challenging part of fitting a prosthesis. “The prosthesis for limb-loss patients who undergo OI has a knee, shin and foot and is connected directly to the femur,” he says. “It offers much more range of motion and allows people to be more mobile because they’re more comfortable. There’s another advantage called osseoperception. We’ve found that people who have an osseointegrated prosthesis have more perception of the ground. If they walk on grass or uneven surfaces, they can feel the difference because the vibrations travel up to the femur bone. There’s quite a bit of literature about this, and we’re continuing to do research.”

The OI Surgery

David Doherty Jr., MD, assistant professor of orthopedic surgery at UTHealth Houston and adult reconstruction specialist, performs the surgery at the Memorial Hermann | Rockets Orthopedic Hospital. In the operating room, a specialized implant that permanently bonds to the bone is inserted into the femur, which will eventually attach to the prosthesis; the device is a micro-porous, titanium implant that biologically bonds with the residual limb.

“We use the term osseointegration, but the more appropriate medical term is direct percutaneous skeletal attachment,” Dr. Doherty says. “The surgery quite literally directly attaches a robotic prosthetic leg into the patient’s skeleton. The benefits are numerous.”

Alex Weatherford was an early OI patient and the first bilateral amputee for the team. “Alex’s experience with traditional prostheses is typical,” he says. “Persons with bilateral amputations are prescribed and given very advanced prosthetic limbs with microprocessors and technology found in computers and airplanes, and we attach these prosthetic legs with what is basically a plastic bucket. The materials have gotten better and we’ve made technological advances, but the concept is the same one the ancient Greeks used. All of the muscle and skin of the leg is pushed into the prosthesis socket. If you gain or lose weight, your thigh might not fit into the socket. Skin breakdown, pain, falls or lack of confidence are frequent features of above-knee socket users. This leads to noncompliance and lowered quality of life. It’s very common for these extremely expensive prosthetic legs to end up in the closet. The percentage of persons with bilateral amputations in wheelchairs is high, especially patients with bilateral above-the-knee amputations.”

Weatherford recalls meeting Dr. Doherty to discuss the procedure. “He and my wife went to medical school together,” he says. “I liked him and his attitude immediately. He explained everything in terms I could understand. When I was doing research on OI earlier, I talked with a military surgeon on the East Coast, who had performed many OI procedures. He suggested that I ask my surgeon a few specific questions. I did, and Dr. Doherty had the answers.”

In April 2021, Weatherford underwent his initial procedures. He joined a growing number of patients around the world who have had titanium rods inserted into their femurs that will later be used to walk. Shortly after, the stage 2 procedures followed and ultimately, he progressed through his rehab protocol.

“Alex never complained during the entire process,” Dr. Doherty says. “Instead, he said, ‘I know you’re going to make it work.’ He was a calming force for me, his therapy team and his wife.”

The Rehabilitation Protocol

In the United States, OI was initially performed at the Walter Reed National Military Medical Center in Bethesda, Md., through the U.S. Department of Defense. As it became available at other sites, there was a need to adjust the rehabilitation protocol to accommodate the demands of civilian life.

“In the military model of OI therapy, patients see their therapist every day or even twice a day,” says Kristin Reeves, PT, MS, program manager of the amputee and limb loss program, who also is a key member of TIRR Memorial Hermann’s OI team. Reeves modified the Walter Reed protocol to meet the time constraints and insurance requirements of nonmilitary therapy.

After Dr. Doherty clears the patient for therapy, Reeves starts the rehabilitation protocol at TIRR Memorial Hermann Outpatient Rehabilitation – West University. “For the first month, Alex used short training prostheses that lower the center of gravity to load the bone and muscles in a static position,” she says. “We start very slowly because persons with double amputations need time to regain balance. He stood for 30 minutes on the short prostheses, beginning with 40 pounds of weight and moving up from there. We do this gradual weight-bearing program for the first month, and after that we move to the regular prosthesis, but we keep the knee locked and start training on some functional activities. The program includes minimal gait at this stage, with only a small amount of distraction on the bone. Assuming everything goes well, we start traditional gait training on level surfaces, and then as time progresses, we add stairs, ramps and more higher-level activities.”

To speed his progress, Weatherford practiced weight bearing at home. “Then I would go once a week to therapy, just standing for 30 to 45 minutes for the weight bearing. By the time we got to full weight bearing, my long-legs prostheses with the knees had arrived. I switched from the little version to the big-legs prosthesis and practiced balancing.”

“Our patients who have had OI feel that they have better stability because the prosthesis attaches directly to the skeleton, which allows for increased hip range of motion and increased sitting comfort,” Reeves says. “They don’t have the problem of sweating that they have with the traditional socket and liner. They use less energy when using the prosthesis, so they tend to use it more often. Some of our patients have had minor setbacks, but they say they would do it again because of the benefits.”

Moving Forward on Two Legs

Weatherford is past the weight-bearing portion of the protocol, but because he lost both legs above the knee, his continued training is helping him to gain confidence and reach his ultimate goal of unassisted walking.

“I use two forearm crutches and walk as much as I want and wherever I want, and in therapy I’m working on walking without them,” he says. “I’m also working with a trainer at a gym to increase my hip and core strength.”

Weatherford is known for his sense of humor at the Osseointegration Clinic at the Memorial Hermann | Rockets Orthopedic Hospital and the therapy clinic at TIRR Memorial Hermann Outpatient Rehabilitation – West University. “He’s always in the best mood of everyone in the room,” Dr. Doherty says. “He has great family support—his wife is amazing. He’s very positive and very devoted to his family. We are so reliant on therapy at TIRR Memorial Hermann for a good outcome. We couldn’t do it without the entire team, and we’re all really in tune with each patient’s individual needs and goals.”

Dr. Vanodia and Reeves plan to make TIRR Memorial Hermann’s OI rehabilitation protocol available for the benefit of other facilities. “There’s no official protocol for osseointegration rehabilitation available for civilians,” he says. “We’ve had successful outcomes with our protocol, and our patients have said that this has been a life-changing experience for them.”

After seven years in a wheelchair, Weatherford, now 43, goes where he wants to go. “Now I have four kids,” he says. “Our twins were too young to remember me with legs, and the new kids didn’t know I’d ever had legs. It’s an incredible surgery and has been an amazing experience, but I also had a really good life without it. When anyone asks me if I’d do it again, the answer is always yes.”

The multidisciplinary OI Clinic meets once a month at the Memorial Hermann | Rockets Orthopedic Hospital. Potential patients meet with Dr. Vanodia, Dr. Doherty, Kristin Reeves and a prosthetist. Reeves also shares her knowledge of OI rehabilitation and provides support for therapists and patients located in other parts of the country. For more information, email her at tirrlimbloss@memorialhermann.org.