Osseointegration (OI) Implant

Osseointegration (OI) is game-changing technology for patients with limb loss. This innovative surgical technique allows patients with above-knee amputations, who are unable to wear a prosthesis, to walk more comfortably, for longer periods of time, and get back to living a more full and vibrant life.

At Memorial Hermann Health System, we are on the forefront of this revolutionary procedure. We are one of the only programs in the nation to combine this highly specialized amputee implant surgery with an award-winning, long-term rehabilitation program to provide the best possible outcomes.

At TIRR Memorial Hermann, the osseointegration program offers multidisciplinary care for amputees. With coordinated care from surgeons, psychologists, pain medicine and rehabilitation physiatrists, pain management specialists, physical therapists and prosthetists, patients at Memorial Hermann are able to take advantage of leading-edge technology and proven rehabilitation techniques.

What is Osseointegration?

Osseointegration is a surgical technique for amputees that involves direct skeletal attachment. Instead of the traditional prosthetic socket, osseointegration uses an implant that is inserted into the bone and attaches directly to the prosthesis. With OI, there is no need for a prosthetic socket.

Many amputees cannot wear a prosthesis because they have difficulty with the socket fit. Challenges with sockets include pain and soft-tissue complications that can be severe enough to prevent the use of the prosthesis. OI eliminates this problem and improves overall function.

What are Osseointegration Implants?

The implant system is an FDA-approved bone-anchored prosthetic solution. It has two parts: the fixture and the abutment. The fixture is an anchorage element that is surgically inserted into the femur. The abutment is a skin-penetrating device that is connected to the fixture. The prosthetic leg is attached directly to the abutment with a connection device.

This innovative implant allows patients to walk with normal motion that cannot be achieved with a typical prosthesis. With direct skeletal attachment, an osseointegration implant allows for natural anatomic alignment of the prosthetic leg that is continuous with the ground. This alignment is essential for a more normal and stable gait.

Many amputees do not consistently wear their prosthesis because of pain and other complications. Osseointegration eliminates many of the challenges with traditional prosthetic devices and takes the science of limb restoration in a new direction.

One of the biggest differences between a traditional prosthesis and a prosthesis with OI is the concept of osseoperception. This is the ability to feel the difference of walking on various types of surfaces. With an OI implant, amputees can feel a difference between walking on surfaces like grass, carpet, tile, uneven ground or gravel, and are able to adjust to these differences for stability.

Patients with an above-knee amputation who are unable to wear a socket are candidates for osseointegration implants. Successful OI candidates are relatively healthy patients without significant comorbidities. The vast majority of current OI implant patients are young traumatic amputees.

Who is a Candidate for Osseointegration Implants?

Researchers are investigating the effectiveness of OI technology with other limbs, including the lower legs and forearms. In the United States, the femur is the most common bone currently being used with OI implants, however the humerus, tibia and radius are all under investigation for osseointegration.

At this time, OI bone implant surgery is not being used for primary amputations, but that could be a possibility in the future.

OI implants help patients get closer to the way they were before the amputation. By connecting directly to the skeletal system, the implants provide sensory feedback that is not possible with a traditional socket device.

With a traditional prosthesis there is a disconnect between taking a step and touching the ground. Socket devices do not have sensory feedback. Osseointegration provides stability, confidence and a reduced fear of falling, along with the benefit of osseoperception.

With OI implants, patients can expect:

• Improved walking ability
• Increased functional capacity
• Improved sitting comfort
• Improved hip range-of-motion
• Direct prosthesis control with better stability
• Ability to use the prosthesis for longer periods of time
• Fewer soft-tissue complications
• Improved safety with reduced falls
• Better quality of life

OI surgery is a two-stage process. In the first stage, the surgeon implants the fixture directly into the residual femur. The amputation is then closed and allowed to heal around the fixture. After a few months, the patient will be ready for the next surgical procedure.

During the second stage, the abutment is inserted through the skin and connected to the fixture. The prosthesis can then be attached to the abutment.

The most significant risk is infection. Because the surgery involves a transcutaneous (through the skin) insertion and the device remains in place without being covered by skin, there is a risk of infection.

Other possible complications include:

• Loosening of the hardware
• Muscle/joint pain
• Bone fracture
• Nerve pain/neuroma
• Tissue retraction
• Skin irritation

Recovery from the first stage of surgery involves allowing the amputation to heal around the implanted fixture, and the prosthesis is not worn during this time.

Recovery from the second stage of surgery is a longer process. The prosthesis is not used for the first three weeks, and then rehabilitation begins with a progressive weight-bearing program. This phase starts with a short prosthesis to gradually introduce weight bearing to the residual limb. Next, rehabilitation progresses to the use of a “locked” prosthesis in order to begin walking in a controlled manner. Physical therapy lasts a few months while patients learn to walk with the new prosthetic system, gradually decreasing the use of assistive devices and returning to functional activities.

The team of physicians, orthopedic surgeons, therapists, and trainers at Memorial Hermann treat a variety of orthopedic injuries, allowing the active patient to return to their desired activity level in a safe, effective, and timely manner. For more information on available treatment options, physical therapy, or human performance services, fill out the form below.