At UTSW, an innovative procedure offers new hope for amputees
Osseointegrated implants provide numerous benefits over conventional prostheses, surgeons say
DALLAS – Feb. 18, 2025 – Complications after an amputation left Scott Bryson, a 50-year-old father of three, unable to walk. But in the spring of 2024, he took his first steps in nearly a decade after receiving a revolutionary surgical procedure at UT Southwestern Medical Center.
Known as osseointegration or bone-anchored prosthesis surgery, the procedure enhances the patient’s remaining limb (or stump) with a metal abutment that sticks out of the skin to link directly to a prosthetic limb. Osseointegration offers numerous advantages to patients, allowing newfound mobility to those like Mr. Bryson, who can’t wear traditional prostheses.
“Being able to walk and to throw a ball with my kids and grandkids and help my wife cook and clean and do things around the house means the world. Osseointegration is the only way to go for me,” said Mr. Bryson, who lives in Collinsville, Texas.
This technology for amputees is a spinoff from dental implants, an innovation that’s been around since the mid-1960s, explained Jonathan Cheng, M.D., Professor of Plastic Surgery at UT Southwestern. By treating the surfaces of titanium medical implants to make them porous, a patient’s bone can grow onto and into the implant, allowing it to gradually become part of the body. In the mouth, abutments emerging from the gums are used as the base for a prosthetic tooth. Doctors gradually adapted this concept for amputees, with the first implants on which to clip prostheses approved by the Food and Drug Administration in 2020, Dr. Cheng said.
“The implant becomes part of the body, allowing for more natural attachment and control,” he noted.
Multidisciplinary team
Although bone-anchored prostheses have since been adopted by hospitals across the globe, the number of medical centers offering the procedure is still relatively small. UT Southwestern is one of just two hospitals offering osseointegration in Texas and the only one in North Texas. That’s because of the extensive multidisciplinary expertise required for this surgery, said Alexandra Callan, M.D., Associate Professor of Orthopaedic Surgery and a Dedman Family Scholar in Clinical Care at UTSW.
Over several years, Dr. Callan and Dr. Cheng have built a team knowledgeable in caring for patients undergoing osseointegration, with members from UTSW’s Department of Physical Medicine and Rehabilitation, led by physiatrists and including physical therapists, and the UTSW Department of Prosthetics and Orthotics to guide fitting the connector and tightening the abutment screw regularly. The team also partners with the Department of Biomedical Engineering and the Multidisciplinary Pain Clinic, among other centers at UTSW. Together, these care providers work seamlessly to optimize outcomes for those who choose the procedure.
Bone-anchored prosthesis surgeries typically take place in two stages and in patients who have already undergone an amputation, Dr. Callan explained. In the first stage, she and Dr. Cheng work together to contour muscle and fat in the residual limb to prepare it for the bone-anchored prosthesis. They then insert a titanium cylinder into the bone’s medullary space, the hollow cavity within the shaft of long bones such as the femur. Because patients often haven’t used their limbs for weight bearing in a long time – such as the decade Mr. Bryson spent not walking – the bone can be thin and fragile, making this part of the procedure technically demanding, Dr. Callan said.
Over the next several months, the implant is gradually incorporated into the bone, with progression that doctors can see on periodic X-rays. Once the implant is well integrated with the bone, Dr. Callan and Dr. Cheng perform a second surgery to further revise soft tissue at the stump and place a metal abutment onto the end of the cylinder, which extends outside of the skin. After this area is healed, the abutment can support a prosthesis.
So far, the team has performed the first stage of osseointegration surgery on 10 patients, and the second stage on four patients. All surgeries thus far have been on lower extremities, but Dr. Cheng and Dr. Callan have begun evaluating patients with upper extremity amputations as well.
“Interest in this procedure continues to grow because of its many benefits,” Dr. Callan said.
For example, she explained, osseointegrated prostheses are more comfortable and convenient to wear, attaching in a fraction of the time it takes to put on a conventional prosthesis. They provide a viable option for patients with short stumps, who typically can’t wear traditional prosthetic limbs due to challenges with socket fit and comfort. Movement is more physiologically normal than with traditional prostheses, causing a more natural pattern of wear and tear on joints in the affected limb and associated structures, such as the hips and spine. Moreover, patients feel additional sensation through the bone attachment of an osseointegrated prosthesis, allowing them to sense the ground more directly for safer walking. And in the future, Dr. Cheng says, the osseointegrated design could allow for incorporated electrodes that would help patients feel real touch and movement sensation in high-tech prosthetics or move a robotic limb at each joint volitionally, a subject of his research.
‘New lease on life’
A car accident soon after high school graduation shattered Mr. Bryson’s left leg, which never healed completely despite more than 30 reconstructive surgeries over two decades. After infection set in, doctors amputated his leg above the knee in 2015.
Mr. Bryson opted for osseointegration after experiencing neuromas on his stump – benign but painful bundles of nerve tissue that made wearing a traditional prosthetic excruciating. For a decade after his amputation, Mr. Bryson navigated the world primarily on crutches, which he said was exhausting and inconvenient, and gradually damaged his shoulder joints. After undergoing the first stage of his osseointegration procedure in June 2023 and the second stage in November 2023, he started physical therapy at UTSW in January 2024. Working with physical therapist Michael Marmolejo, DPT, and prosthetist Fabian Soldevilla, CPO, he steadily placed more and more weight on his abutment to help rebuild bone mass around the implant. Mr. Bryson slowly progressed from leaning on a chair with a short prosthesis, to walking with rails on a full-size artificial limb, to using two canes and then only one cane. By June, he was able to take steps with no help at all.
Mr. Bryson said that his three daughters, ages 28, 24, and 19, cried when they saw him walk across the living room independently for the first time. He continues to receive physical therapy at UTSW with a goal to gradually increase the amount of time he uses his osseointegrated prosthesis and decrease his reliance on crutches.
“I had to accompany my oldest and middle daughter down the aisle on crutches when they got married. I told my youngest that when she gets married someday, I’ll be able to walk her down the aisle,” Mr. Bryson said. “This is a new lease on life for me and my family, and I owe it to Dr. Callan, Dr. Cheng, and my team at UT Southwestern.”
About UT Southwestern Medical Center  
UT Southwestern, one of the nation’s premier academic medical centers, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty members have received six Nobel Prizes and include 25 members of the National Academy of Sciences, 23 members of the National Academy of Medicine, and 14 Howard Hughes Medical Institute Investigators. The full-time faculty of more than 3,200 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide care in more than 80 specialties to more than 120,000 hospitalized patients, more than 360,000 emergency room cases, and oversee nearly 5 million outpatient visits a year.