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Fig. 1 Illustration of a right transfemoral amputation fitted with an osseointegration implant. The lateral soft tissues and bony cortex are removed. The skin stoma surrounds the gold portion at the distal aspect.

AAOS Now

Published 7/1/2018
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David B. Doherty Jr, MD

Will Osseointegration Become the Standard of Care for Amputees?

Experiences from war-torn Iraq

When I arrived at the Ibn Sina Hospital in Baghdad, Iraq, I was stunned to see the conditions of some of the patients. I had never been in a war zone, and although the active fighting was north of Baghdad, the steady flow of subacute and chronic injuries into the clinic seemed never-ending. Until then, hasty battlefield reductions and wound closures had been the definitive treatments. The patients were all soldiers who had been fighting ISIS, and many of their comrades had lost their lives; at times, I thought those were the lucky ones.

Iraq is not a friendly place for the disabled. The country has few accommodations for those in wheelchairs and people with other disabilities. Worse yet, disabled people are often shunned. Given that many wounded soldiers are in their 20s, the potential loss of quality and productive life-years is staggering. One patient summed it up for me, explaining that the parents of his fiancée would no longer allow their marriage because he had lost his leg in battle and was having trouble maintaining employment due to prosthetic difficulties.

Recognizing the need for solutions to this mounting problem, the Iraqi minister of health and prime minister reached out to Iraqi-born Australian surgeon Munjed Al Muderis, MBChB, FRACS, FAOrthA, to begin a program to treat wounded anti-ISIS soldiers. In addition to specializing in lower-extremity reconstruction, Dr. Al Muderis is a pioneer in the field of osseointegration. After spending two months in Sydney, Australia, observing his techniques, I became fascinated with the technology and the potential it offered patients who had sustained limb loss. I was, therefore, excited to join Dr. Al Muderis’ team in Iraq and to work with the technology.

Osseointegration’s potential

Researcher Per-Ingvar Branemark, who first discovered osseointegration in the late 1960s, found that living bone had the capacity to grow into pores and gaps in titanium implants. From there, the technology rapidly evolved, and it is now an integral concept in orthopaedic surgery and oral and maxillofacial surgery. Within orthopaedics, bony ingrowth is central to a variety of important reconstructive procedures, including press-fit joint replacements, interbody spinal fusions, and a variety of foot and ankle procedures.

Since the 1990s, specialized implants that utilize these principles have been developed for the treatment of amputees, and this class of devices and procedures has been generally termed “osseointegration.” The need arose from limb-loss patients who were unable to tolerate socket connections of their prosthetic limbs. The surgery itself combines a soft-tissue procedure where muscle is secured to the distal bone and excess fat and skin are removed with a bony procedure where reamers and broaches prepare the medullary canal for a fully porous coated titanium rod that will ultimately protrude through the skin (Fig. 1). The portion that is visible at the end of the residual stump replaces the need for a socket, as a patient is then able to directly attach the prosthesis to the rod contained within the canal of his or her bone (Fig. 2).



Courtesy of William Lu, PhD

Fig. 1 Illustration of a right transfemoral amputation fitted with an osseointegration implant. The lateral soft tissues and bony cortex are removed. The skin stoma surrounds the gold portion at the distal aspect.
Fig. 2 Right transfemoral amputee with a mature stoma and fully integrated implant.

Several implant systems and protocols for osseointegration surgery are in use. The current, percutaneously placed devices rely on bony ingrowth from the medullary canal onto the implant. This ingrowth then offers a secure interface between the patient’s skeleton and the prosthesis. Although some patients may experience superficial soft-tissue infections, none of the hundreds of patients who have undergone the procedure with Dr. Al Muderis’ current prosthesis and single-stage implantation technique has experienced a deep infection requiring implant removal. As osseointegration surgical techniques and preoperative and rehabilitation protocols evolve, complication rates will likely decline even further.



Courtesy of David B. Doherty, Jr, MD

These successes have expanded the indications for osseointegration. However, most centers continue to reserve this technology for young, otherwise healthy transfemoral amputation patients who have experienced socket-related difficulties with previous prosthetics. These patients are ideal candidates for osseointegration, as they usually have healthy soft tissue and an abundant vascular supply to support bony ingrowth and develop a healthy stoma, free of infection. Current literature suggests that these patients experience significant improvements in quality of life, prosthetic use, and mobility. Patients consistently report that the change in their bodies is revolutionary.

Osseointegration in action

I was thrilled to travel to Iraq to expand upon my experience with Dr. Al Muderis and see the technology applied in a setting that would challenge us all as surgeons.

In the first days of the trip, we saw patients who had undergone osseointegration three months earlier during Dr. Al Muderis’ first trip to Baghdad. None of the patients had developed an infection, and most were ready to be fit with their definitive prostheses and begin full weight-bearing. We witnessed many happy patients walk for the first time since sustaining their injuries. As a young surgeon about to graduate from residency, I have spent the past five years vigorously training, admittedly losing the forest for the trees, as I often focused on the details and minutiae of procedures and daily rounds. Being able to take a step back and watch someone walk again thanks to groundbreaking technology reinforced and reengaged my deepest motivations to pursue orthopaedic surgery.

In one particularly memorable patient, shrapnel from a bomb had injured both of his legs. His right leg was so severely mangled that he underwent an acute transfemoral amputation at a very high level. He was left with a short, fleshy stump with a femur length of about 15 cm. He had never been able to tolerate traditional socket prostheses and could only use crutches for short distances. As such, he had been confined to a wheelchair for the past several years. He was a prime candidate for osseointegration. His surgery would nevertheless be a challenge, as we could not use a tourniquet and had only the bare-minimum femur with which to work. After his surgery, he typified the average osseointegration patient, remarking on how stable the implant was and how radically different his leg felt and appeared. He could not get his definitive prosthesis soon enough to reclaim his life.

Osseointegration combines foundational orthopaedic principles and techniques and applies them in a novel way to improve patients’ lives. For this reason, I believe it has a bright future. As with many implants and procedures that have preceded it, there is a concerted effort to improve osseointegration technique and mitigate complications. With time, I believe the technology could replace traditional amputee care, particularly for an ideal subset of patients. I am grateful to have had the opportunity to learn and experience osseointegration in Iraq. It reminded me how fortunate we are to be able to participate in our patients’ lives in such positive ways.

David B. Doherty Jr, MD, is a chief resident of orthopaedic surgery at the University of Texas Health Science Center at Houston. He will begin a fellowship in adult reconstruction at Duke University in August before returning to Houston to practice.