Mr Matija Krkovic is one of the few specialist orthopaedic surgeons in the UK who is able to use osseointegration in limb replacement surgery for amputee patients. This cutting edge surgery is a breakthrough in amputation surgery and helps amputee patients who cannot tolerate using a socket prosthesis.
Osseointegration is the medical term used to describe bone growing into a metal (usually titanium) implant. Osseointegration has successfully been used for decades in dentistry (for dental implants) and joint replacement surgeries, however, it has only recently been used in amputation surgery with remarkable results. In Osseointegration limb replacement surgery, a titanium prosthesis is directly connected to the skeleton, and is aligned with the residual limb.
Osseointegration was first used in clinical practice in 1965, with Professor Per-Ingvar Branemark who successfully inserted titanium implants into the upper and lower jaw as anchor points for dental implants. Whilst it became well accepted technique in dentistry soon after the initial implementation in 1965, it’s first use in an amputee took place in 1990 where prof Brånemark’s son inserted the first transcutaneous femoral intra-medullary prosthesis in a patient with an above knee amputation.
Osseointegration limb replacement surgery can be performed in the following bones:
With traditional socket prostheses, some patients have a poor fit between their residual limb and the prostheses, despite multiple adjustments. This is because there can be significant changes in the size and shape of their stump in the first 24 months after amputation.
The most commonly reported problems with standard socket type prosthesis are:
As a direct consequence of the above problems, certain amputees cannot use their prostheses more than a few hours per day and quite often not even on a daily basis.
Apart from physical problems with the socket type prostheses, which are related in a majority of the cases to socket-skin interface, people will also notice:
Both consequences are as a direct consequence of increased energy consumption (oxygen consumption) which is very likely directly related to the level of amputation in the lower limb.
In a standard socket prosthesis, force to the prosthesis is delivered from the muscles, which move the bone stump. During movement, the soft tissue in the stump (i.e. muscles, subcutaneous fat and skin) are compressed against the prosthesis socket. This can cause significant pain, discomfort and swelling over time for amputee patients.
In osseointegration implantation, the amputated bone stump is directly connected to the prosthesis with no “slack” in the system. Muscles are moving the bone stump together with the metal stem inserted. This avoids the need to compress the soft tissue inside a socket prosthesis as before, making it a more efficient mode of travel. Because the prosthesis does not need to be attached to a socket, all socket related problems are completely removed, thanks to osseointegration. This includes heating or sweating in the prosthetic socket, sores or skin irritation from the socket and the inability to walk in woods and open fields.
Patients who undergo osseointegration surgery for amputation report the following advantages over patients with socket prostheses:
An additional benefit is that an osseointegrated implant prosthesis can in fact it can save money when compared to a standard socket prosthesis.
Haggstrom et al showed in their work that osseointegrated patients need fewer follow-up visits and that the average total annual cost for new prostheses, service, repairs and adjustments was 14% lower for osseointegrated implant prostheses compared to socket-suspended prostheses.
Patient having problems with conventional socket prostheses like:
In addition to the above, patients must:
Have reached full skeletal maturity (i.e. not suitable for children)
Have typical skeletal anatomy
Be aged between 18 and 70 years old
Be suitable for surgical procedure on the basis of medical history and physical examination (i.e. don’t have significant other medical conditions)
Agree to comply with the treatment program and follow-up.
Patients with the following conditions may not be suitable for osseointegration surgery at our Cambridge clinic. We recommend arranging a consultation to discuss whether or not you are suitable. These conditions include:
Every patient who undergoes Osseointegration amputation surgery is looked after by a multidisciplinary team of healthcare professionals. Each member of the team is essential in looking after different aspects of care for the patient. The team includes:
Osseointegration surgery is very safe for all types of amputation, however like all surgery it is important to be aware of the possible complications. The main complications related to osseointegration procedure are:
Many patients who undergo osseointegration surgery will experience superficial infections which can present with pain, redness, swelling and discharge from around the stoma. These are referred to as ‘superficial’ as they only involve the skin and subcutaneous tissues and the bacterial has not penetrated deeper inside the limb. Depending on the severity of the infection and type of bacteria involved, this infection will be treated with oral or intravenous antibiotics.
It is well accepted that superficial infection rate is 100%, meaning that it is extremely likely that every osseointegrated implant patient will experience this complication at least once, therefore every single patient we treat at our Cambridge clinic has to be aware of it but also be able to recognise early signs and react upon them as soon as possible. Even a few hours delay can result in prolonged treatment and increased pain.
Deep infections are not as common with osseointegration. Deep infections are ones which have penetrated deeper into the limb and can involve the bone and prosthesis. Around 20% of patients will experience deep infection/osteomyelitis (infection of the bone) in the first 10 years post osseointegration. Almost half of them (9% of all patients) will need their implant removed and be treated for osteomyelitis. If the osteomyelitis is successfully treated, the stem can be reinserted.
Periprosthetic fractures, or fractures in the bone around the osseointegrated implant prosthetic, can happen during the insertion of the implant into the bone during surgery or can happen at a later stage, mainly because of a fall or other traumatic incident. The incidence of periprosthetic fractures is between 10-25%. The fractures are treated using standard implants for bone fracture fixation, only in specific cases, custom made implants must be used for the osseointegration process.
Aseptic loosening is when there is the failure of the bond between an osseointegrated implant and amputated bone in the absence of infection. Aseptic loosening is a complication in many forms of orthopaedic surgery, including for example hip replacement surgery.
It is not clear if aseptic loosening is not actually a low-grade infection. Treatment involves the removal of the implant and microbiological evaluation of the samples from the medullary canal taken during the surgery. If all samples are negative, the stem can be re-inserted earlier otherwise we will follow the same pathway as in confirmed deep infection cases.
The average hospital stay at our London and Cambridge clinics is three to four days. The growth of the bone into the implant takes about three months. Most patients can walk without crutches within about three months post first stage surgery or shortly after the second stage.