Transplantation of the extensor apparatus
(extensor mechanism allograft)
Transplantation of the extensor apparatus is one of the most delicate and complex process of reconstructive knee surgery.
It is indicated in those patients that have been placed a knee prosthesis and no significant injury or anywhere incompetence extensor mechanism. Also in patients with knee arthrodesis to which it can be fitted for a prosthesis.
The knee extensor consists quadriceps tendon, the patella and patellar tendon. The integrity of its components is vital to the knee to function properly. When the patellar tendon, the quadriceps extensor apparatus or full irreparably injured, after placement of a total knee replacement, or due to a tumor or malformation, a very difficult problem to treat arises. Luckily, this occurs infrequently (an 0,17 a un 2,5% of total prostheses total Rodilla).
Si any of the components of the extensor apparatus is injured, a loss of the ability to extend the knee occurs. It is a very debilitating injury that prevents the patient walk normally. Walking, the patient has to wear a brace, that is a device that locks the knee straight, and in case that it can not make, you must use a wheelchair. Also, muscle loss and high forces exerted on the total knee components make loosening soon. For example, if the patellar tendon ruptures, ascends the patella quadriceps muscle strength. If not treated properly, the consequences are devastating: on the one hand, knee loses functionality and we must resort to a wheelchair to move around and, other, looseness in the knee occurs in less than 1 year. Due to loosening is necessary to change the total knee replacement at the time of rebuilding the injured extensor, so that the patient can walk normally again.
June 2006, University Hospital Son Dureta, el Dr. Andrés Camprodon performed the first transplant complete extensor. He rebuilt a knee that had lost tissue after severe infection.
The transplantation of extensor apparatus consists of grafting a new quadriceps tendon, A new spherical, a new patellar tendon and tibial tuberosity fragment of a donor (these are obtained from the Tissue Bank, that ensures their safety and quality). This transplant has the added difficulty that almost always change the total knee replacement in the same operation. The change of prosthesis must do it in extremely difficult scenarios in which there has been a disproportionate loss of bone. Full allograft extensor apparatus consists of a complete fragment of tibial tuberosity, the patellar tendon, the patella and quadriceps tendon frozen, to replace the absent or deficient, and implanted by a meticulous technique.
Since 2006 el Dr. Camprodon has successfully rebuilt numerous roller that lacked extensor apparatus. It is a very demanding technical, requiring a long learning curve. Mostly involves changing the knee in the same surgical procedure, scenarios bone mass loss.
Restoration of the bone around the knee
Bone loss around the knee at around total knee replacement is a challenge for orthopedic surgeons. When bone loss is a good choice are massive massive bone allografts, pose for a durable and solid reconstruction, allowed to bear weight and regain mobility.
Sometimes, when the surgeon has to perform a knee replacement prosthesis or a change has to face a loss of bone mass, because of previous infections, tumors, trauma. In these cases it is impossible to place or change a knee without restoring bone mass. Transplantation of the extensor apparatus requires a meticulous technique, where every detail counts. This procedure requires a unique skill, thus placing the new dentures went really must be perfect to ensure the success of the extensor apparatus replacement. You need to give it the proper tension, for if the voltage is too, the patient can not flex the knee fully, conversely, if the voltage is insufficient, extension will not be complete.
Recovery To ensure the success of this operation is necessary to follow the instructions of the orthopedic surgeon in detail. Strict rehabilitation protocol and lengthy set that includes the complete immobilization in a cast for 9 weeks.
Dr. Camprodon is one of the few surgeons worldwide who perform successful transplantation of the knee extensor.