Biomedical subjects

T I Younger

Publications and source records attributed to T I Younger.

6 recordsLinked to original sources

PubMed1995

Extended proximal femoral osteotomy. A new technique for femoral revision arthroplasty.

An osteotomy technique for removal of distally fixed cemented and cementless femoral components is described. The anterolateral proximal femur is cut for one third of its circumference, extended distally, and levered open on an anterolateral hinge of periosteum and muscle. This creates an intact muscle-osseous sleeve composed of the gluteus medius, greater trochanter, anterolateral femoral diaphysis, and vastus lateralis, and exposes the fixation surface as well as distal cement. This technique combines the advantages of an extremely wide exposure of component fixation surfaces and preservation of soft tissue attachments to cut bone. In addition, it allows alteration of the proximal femur to facilitate accurate and safe distal cement removal and canal machining under direct vision. The possibility of placing the component in varus is eliminated. The proximal femur is allowed to conform more accurately to the revision prosthesis, a weakened or damaged trochanter is protected from iatrogenic injury, and soft tissue tension can be adjusted. The osteotomy is then repaired with cerclage wires or cables. The first 20 patients treated with this technique are reviewed. Excellent cement and component removal and optimal revision component implantation were obtained with no change in postoperative regimen and reliable healing.

Adult↗

PubMed1995

Removal of a well-fixed cementless femoral component with an extended proximal femoral osteotomy.

Removal of a stable, well-fixed cementless femoral arthroplasty component occasionally is necessary because of infection, component malposition, persistent pain, or incompatibility with a femoral revision component. Restricted access to ingrowth surfaces may make implant removal exceedingly difficult and increases the risk of iatrogenic damage to the proximal femur. A new extended proximal femoral osteotomy technique is described for use in removing well-fixed cementless femoral components. Previous techniques have been modified to allow access to the bone-implant interface and to provide straight-shot access to the femoral canal for proper sizing and positioning of the revision implant. The osteotomy can be extended to accommodate the entire length of the porous coating on the revision component. If a shorter osteotomy is desired, access to the prosthesis for transection with a metal-cutting burr is possible. The osteotomy is easily repositioned with cerclage wires or cables and reliable healing has been demonstrated.

Aged↗

PubMedDate not supplied

Classification of bone defects in failed prostheses.

The authors report a classification system in grades, based on preoperative x-rays of the bone loss surrounding a loosened implant that may be cemented or cementless. Moreover, this classification system allows for the prior choice of which prosthesis to use at the time of reimplantation, and which type of graft depending on whether or not the residual bone guarantees mechanical hold of the implant.

Acetabulum↗

PubMedDate not supplied

Femoral reconstruction with massive allograft and cementless prosthesis.

Classification of loss of bone substance in cases of prosthetic loosening allow for planning of the most suitable type of reconstructive surgery. The use of cemented prostheses has revealed negative long-term results. For this reason a cementless implant which is entirely coated is preferred in order to allow for distal anchoring (particularly in type 2B and 2C loosening). In more severe cases cancellous or cortical bone grafts stabilized by wiring will be used.

Bone Resorption↗

PubMedDate not supplied

Acetabular reconstruction with massive allograft and cementless prosthesis.

The authors standardize the method to use for a correct approach to acetabular reconstruction in relation to the loss of bone tissue. In type 1 or 2A and C loss, cancellous bone and porous hemispheric acetabula may be used. In type 2B loss there are 3 options: a small acetabulum with a high rotation center, a larger component leaving 30% of the superoexternal portion uncovered, or a larger component with a supporting superoexternal graft. Type 3A requires a supporting graft of distal femur or proximal tibia fused with screws to which a porous hemispheric component with screws is applied. Finally, type 3B loss requires the use of a massive homologous graft fused to the ilium with screws and a component in cemented polyethylene.

Acetabulum↗

PubMedDate not supplied

Hip revision surgery with cemented, cementless or hybrid prosthesis.

The authors report how the choice of a prosthesis for implantation (cemented or cementless), must be made only after a careful evaluation of the type of osteolysis present. This preoperative evaluation, based on a classification that was previously described, will also guide the choice of any grafts that may be of small size to massive depending on the loss of substance.

Bone Cements↗