Should your prosthesis be anchored to the bone?

Traditionally a prosthesis is fitted onto the place of amputation with the help of a socket. However, osseointegration could do away with sockets for good – at least for the right candidate

Bone anchoring prosthesis or osseointegration refers to a prosthesis attached directly to a patient’s skeleton or bone at the place of injury or amputation. The first patient to receive this treatment in South Africa was operated on in Cape Town on November 5, 2018.

This technology emerged in the late 1950s, with dental implants followed by facial and silicone finger attachments. For trans-femoral prosthesis (above-the-knee amputation) the procedure starts with the surgically insertion of a titanium rod into the marrow space of the bone. Six months later a titanium extension called an abutment is attached to the titanium rod.

The attachment protrudes through the soft tissue and the skin at the bottom of the patient’s stump. Over the following six months a very strict rehabilitation programme gradually introduces weight bearing on a prosthesis that is attached directly to the abutment.

Usually, a patient who receives this surgery has a 12-week rehabilitation programme during which they make  use of two crutches for six weeks and a single crutch for the following six weeks.

This particular surgery can have many benefits for the patient, but also involves a number of challenges. The Amputation Coalition of America lists some of the benefits and disadvantages on its website:

What are the advantages?

• No sweating or skin irritations, as is common with a socket;

• None of the pain, pressure or discomfort caused by a socket;

• The prosthesis can be put on and taken off easily;

• Excellent suspension;

• No restriction of hip movement;

• Comfort in the sitting position;

• Osseoperception – a more natural sensation of the prosthetic limb; and

• An increase in bone and muscle mass.

What are the disadvantages?

• Long rehabilitation process (a total of up to 18 months);

• Risk of infection;

• Risk of fractures and loosening of the implant;

• Poor cosmesis (restoration of physical appearance) due to permanent abutment;

• No high-impact activities such as running or jumping are permitted; and

• Swimming at public facilities are not recommended.

It should be clear from the above that not everybody is an ideal candidate for osseointegration. However, for the right person it could be a life-changing surgery.

Heinrich Grimsehl is a prosthetist in private practice and a member of the South African Orthotic and Prosthetic Association (SAOPA). email: info@hgprosthetics.co.za