Revision: Hip Prosthesis Operation
What exactly is it?
Total hip replacement surgery is performed in order to maintain a functional life for people who cannot even perform their daily activities due to uncontrollable hip pain. However, problems that may develop may necessitate the replacement of the prosthesis. The process of replacing some or all parts of artificial hip joints (prostheses) that were put in during hip prosthesis surgery is called revision hip prosthesis. The purpose of this operation is to reduce the pain and restore functionality, just like in the first operation.
Why and when do we need it?
There are numerous reasons for a hip prosthesis to be replaced, which can be divided into two categories: mechanical and infectious.Infectious causes include infected prosthetic equipment and its surrounding soft tissue and bone.Mechanic reasons are painful and unfunctioning events such as disintegration (being loose) of the prosthesis and bone, corrosion of metal and/or plastic prosthesis parts, instability (abnormal movement), prosthesis bulging, bone fracture around the prosthesis, and eburnation.
Revision hip prosthesis due to infection:
Infection is a potential problem that may occur after all surgical procedures. We can define prosthetic infection as the appearance of bacteria in the prosthetic parts and/or the surrounding bone. Infection occurring in the first 6–8 weeks after surgery is called the “early period,” while infection occurring after this period is called the “late period.” Treatment is planned according to this classification.
In early-stage infections, debridement and limited component replacement (insertion) are usually performed. Cultures taken around the prosthesis during this surgery determine the antibiotic treatment to be applied in the next period. In addition, artificial joint parts are washed with special solutions. Antibiotic treatment after surgery is permitted and allowed to be effective.
In late-stage infections, there is a factor that causes infection in artificial joint parts and adjacent bones. Usually, a single or two-stage surgical procedure is performed, which will require the replacement of all artificial joint parts.
In a single-stage surgical procedure, the primary prosthesis is removed in the same operation and the adjacent bone is mechanically cleaned. Cleaning is the removal of dead tissue. The remaining bones and joint space are washed with special solutions, and a new prosthesis is placed. Antibiotic treatment is started according to the microbes produced as a result of cultures taken from the prosthesis and bone. Follow-up is done with the infection parameters in the blood.
In two-session revision surgery, the bone is debrided after the infected prosthesis is removed. A temporary prosthesis made of antibiotic bone cement is placed to fill the gap. Appropriate antibiotic therapy is given against the causative microorganisms. By monitoring the infection parameters in the blood values, it is decided when the second surgery will be performed. This period varies between six and eight weeks. When suitable conditions are met, the temporary prosthesis is removed and a revision knee prosthesis is attached. An average of six months of antibiotic therapy may be required after this surgery.
Revision surgery due to relaxation and corrosion:
The factors causing loosening may change according to the technological condition and the technique of the first-placed prosthesis. The disruption of the knee prosthesis’ grip on the bone is called relaxion. The micro movements that occur as a result of relaxation cause pain and bone corrosion.In some cases, the microfragments that are sourced from plastic material at the environment of friction of prosthesis parts cause the activation of the immune system by gathering around the prosthesis. This reaction may affect the bone around the prosthesis, and bone loss called osteolysis may develop. This loss means the relaxation of the connection between the prosthesis and bone. In revision surgery, due to loosening and wear, mostly all artificial joint parts are replaced. However, in cases where the bone has lost volume and is weak, additional implants, apparatus, and bone grafts can be used to attach the revision prosthesis to the bone.
Revision surgery due to repetitive dislocation
For hip prostheses to work properly, the ball-shaped head must be mobile in a lair. In cases of harmony disturbances with some positions and movements, hip prosthesis dislocation is in question. In cases of repetitive dislocation, revision surgery is needed to replace the prosthesis placement positions or to place materials to avoid dislocation.
Revision surgery due to a fraction of bone around the prosthesis
A periprosthetic fracture is the loss of bone around a prosthesis caused by trauma. The revision surgery is subject to change based on the prosthesis’ grip on bone and the geometry of the fracture. If the prosthesis’s connections to the bones are not damaged, bone detection methods (plate, screw, wire, etc.) are used instead of replacing the prosthesis, whereas the hip prosthesis is replaced with a revision hip prosthesis if there is damage.
