Biomedical subjects

Y Itami

Publications and source records attributed to Y Itami.

At least 19 recordsLinked to original sources

PubMed1983

A clinical study of the results of cementless total hip replacement.

We introduce our total hip prosthesis, its operation technique, and report the clinical results. Ours does not use bone-cement, but its design, together with the use of original bone and new bone formation surrounding it, results in a biological anchoring. Since 1978, we developed for this new type of total hip prosthesis 6 sizes of stem to fit more rigidly within the intramedullary canal of femur. The new femoral component also has larger notches on its surface than did the old one. Our results of 144 cases (147 joints) ranging from 2 to 10 postoperative years giving an average of 4.4 years, are quite satisfactory. Blood loss during the operation is as little as 480 ml. The few complications observed differ from those of the Charnley type, and will be reduced greatly when the operation is yet more cautiously and skillfully done. Unilateral replacement in bilaterally affected patients improved the condition of the unoperated side in 30% of the cases.

Adult↗

PubMed1982

The direct fixation system of total hip prosthesis. Research of the possibilities of fixing total hip prosthesis directly to bone.

There are two methods for the fixation of prostheses to bone; one is a method using bone cement and another is the direct fixation of the prostheses to bone. Four types of animal experiments were performed to compare the two methods of fixation. A small pyramid shaped test piece was used to compare the fixation capacity of the socket spike. Also, a special test piece was used to study the time of bone formation, to check the fixation capacity of bone bar formation occurring in the hole in the based part of the prosthetic component. furthermore, models of prosthetic stem and socket were made and attached to the femur and ilium of dog to perform fixation tests and fatigue tests. As a result, any of the tests proved that the direct fixation method without the usage of bone cement was superior to the fixation method using bone cement.

Acetabulum↗

PubMed1982

A cementless system of total hip prosthesis. Experimental studies on total hip prosthesis in dogs.

It is essential that the prosthetic material should not be harmful to the human body, it should be strictly fitted to the body and it should have sufficient durability. To investigate those conditions of an artificial joints as mentioned above, it is important to have experimental studies using a model of the artificial joint in animals instead of a simulator. The authors have developed their own total hip prosthesis for a dog since 1970. These prostheses were fixed to the bone without bone cement. These dogs were killed periodically from 8 weeks to 3 years after surgery of total hip replacement. Not only were pathohistological studies on the joint capsule and bony tissue of the femur surrounding the prosthesis performed, but also scanning electron microscopic examination on capsule and the surface of the prosthetic head were performed. The results were excellent. Ther was no loosening or wear when the new type of acetabular socket with large spikes was used. On the other hand, in the case of the old type socket with its smooth surface and smaller spikes, loosening of the socket and prosthetic stem occurred within one year after surgery.

Animals↗

PubMed1978