Chisel tip lets it hug prosthesis to help prevent perforation.

01/12/2017 · The Wagner prosthesi..

K113556 - WAGNER CONE PROSTHESIS SYSTEM

From January 1, 1993 to December 31, 1995, 98 patients were operated upon by the designer, Professor Heinz Wagner and received 132 total hip replacements involving the cone prosthesis. Of this patient population, six patients died and another five could not be contacted for follow-up examinations. After an average follow-up time of 11.5 years (range: 10–14 years), 94 cases (87 patients) were available for clinical and radiographic analysis.

Wagner revision of prosthesis stem [in German]

The short-term results are reported for 43 hip revision operations with the long-stemmed Wagner prosthesis. The patients were followed-up for an average of 25 months. The Charnley scores were; pain 5.2, movement 4.0 and walking 4.0. All patients except one showed abundant new bone formation. The stem subsided more than 20 mm in 5 patients and in 22 the subsidence was less than 5 mm. The major complication was dislocation, which occurred in 9 patients; 8 of these were reoperated and from then on remained stable.

Specific diagnostic indications foruse of the Wagner Cone Prosthesis are:0 patient conditions of noninflammatory degenerative joint disease (NIDJD), e.g.,avascular necrosis, osteoarthritis, and inflammatory joint disease (IJD), e.g.,rheumatoid arthritis;those patients with failed previous surgery where pain, deformity, or dysfunctionpersists;revision of previously failed hip arthroplasty.


Long-term results of the Wagner cone prosthesis - …

The most important part of any prosthesis is the socket, which provides the man-machine interface. During the initial assessment of the amputee, examination of postoperative radiographs and careful palpation of the pelvis are recommended. Some amputees present as "hip disarticulation" when they have a short femoral segment remaining or as "transpelvic" when part of the ilium, sacrum, or ischium remains. Unanticipated bony remnants can become a puzzling source of discomfort. On the other hand, they may sometimes be utilized to assist suspension or rotary control or to provide partial weight-bearing surfaces. Due to the success of ischial containment transfemoral sockets, the importance of precise contours at the ischium and ascending ramus is now more widely recognized. The same principles can readily be applied to hip disarticulation sockets to increase both comfort and control (Fig 21B-11.).

The Wagner revision prosthesis consistently restores …

We prefer to have the amputee simulate weight bearing during the plaster impression technique to create as precise a mold as possible. However, in contrast to the technique advocated by Otto Bock, we believe that careful attention to shaping the medial wall in the ischial region is important to improve control of the prosthesis for both walking and sitting.

Long-term results of the Wagner cone prosthesis (PDF …

The Wagner cone prosthesis is indicated in uncemented total hip replacement of cases with cylinder-shaped femurs, deformed femurs, femurs with increased antetorsion, and in conditions of intramedullary bony scar tissue after previous osteotomies. The objective of this study is to present long-term results. From January 1, 1993 to December 31, 1995, 132 implantations were made with the Wagner cone prosthesis. We report the clinical and radiographic results of 94 cone prostheses with a mean observation period of 11.5 years. The Merle d’Aubigné score improved from a preoperative mean value of 8.8 to a postoperative mean of 16.3. The radiographic evaluation revealed 32 cases with cortical hypertrophy, 73 cases with atrophy of the proximal femur, and 18 cases with complete pedestal formation. Radiolucencies over Gruen zones 1 and 7 occurred in 42 cases; only zone 1 was affected in 24 cases. Complications included three deep infections, three acetabular revisions, five total joint revisions, one recurrent luxation, and three heterotopic ossifications. In spite of the fact that the examined cohort often included patients who had undergone multiple previous operations (a maximum of six) of the proximal femur or the acetabulum, the long-term results of the Wagner cone prostheses were very promising.

The use of the Wagner revision prosthesis in complex …

Torque-absorbing devices are often added to hip dis-articulation/transpelvic prostheses to reduce the shear forces transmitted to the patient and components. Ideally, they are located just beneath the knee mechanism (Fig 21B-9.). This increases durability by placing the torque unit away from the sagittal stresses of the ankle while avoiding the risk of introducing swing-phase whips (which can occur if it is placed proximal to the knee axis). The major justification for such a component is that the high-level amputee has lost all physiologic joints and, hence, has no way to compensate for the normal rotation of ambulation.