The Journal of bone and joint surgery. American volume
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J Bone Joint Surg Am · Jan 1999
The porous-coated anatomic total hip prosthesis, inserted without cement. A prospective study with a minimum of ten years of follow-up.
One hundred consecutive primary total hip arthroplasties performed with use of a porous-coated anatomic total hip prosthesis, fixed without cement, in ninety-one patients were followed prospectively for a minimum of ten years. At the time of the most recent follow-up, twenty patients (twenty-three hips) had died and seventy-one patients (seventy-seven hips) were living. The average age of the living patients was sixty-six years (range, thirty-two to ninety-two years), and their average Harris hip score was 84 points (range, 33 to 100 points). ⋯ Femoral osteolysis occurred in thirty-nine hips: in the proximal aspect of thirty-one hips, in the distal aspect of four, and in both the proximal and the distal aspect of four. The durability of the femoral fixation documented in this study is especially encouraging in view of the fact that this was our initial experience with devices fixed without cement and that a so-called first-generation femoral component was used. However, the study also demonstrated that not all acetabular components fixed without cement function well over the long term and that specific design considerations (adequate initial fixation, congruency between the liner and the shell, an optimum shell-liner capturing mechanism, and a smaller femoral head) are warranted.
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The records concerning ten consecutive years of experience with Monteggia fractures in adult patients at a level-one trauma center were retrospectively reviewed. Forty-eight patients who had been followed for a minimum of two years (average, 6.5 years; range, two to fourteen years) were identified. There were twenty-five women and twenty-three men, and the average age was fifty-two years (range, eighteen to eighty-eight years). ⋯ The results of the present series are much better than those reported in most earlier studies, suggesting that stable anatomical fixation of the ulnar fracture (including associated fracture fragments of the coronoid process) with a plate and screws inserted with use of current techniques of fixation leads to a satisfactory result in most adults who have a Monteggia fracture. The posterior (Bado type-II) fracture is the most common type of Monteggia fracture in adults. Problems with the elbow related to fractures of the coronoid process and the radial head, which are common with Bado type-II Monteggia fractures, remain the most challenging elements in the treatment of these injuries.
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J Bone Joint Surg Am · Nov 1998
Polyethylene wear after total hip arthroplasty: the effect of a modular femoral head with an extended flange-reinforced neck.
The use of modular components in total hip arthroplasty has been thought to contribute to accelerated polyethylene wear. Specifically, a modular femoral head with a flange extension and a longer neck may cause increased wear. The purpose of the current study was to evaluate the effect of a flange extension on polyethylene wear. ⋯ Multivariate analysis showed that the presence of a flange extension was associated with increased polyethylene wear to a greater degree (F = 2.86) than were all other variables that were measured, including a younger age (F = 1.72), a more vertical angle of the acetabular component (F = 0.49), a heavier weight (F = 0.14), male gender (F = 0.11), and a smaller initial thickness of the polyethylene (F = 0.02). These data support an association between the presence of a modular femoral head with a flange extension and an accelerated rate of polyethylene wear. The presumed mechanism is an increase in peripheral, or so-called rim, impingement of the flange-reinforced neck on the acetabulum due to a decrease in the ratio between the diameters of the femoral head and neck.