Search

In a matched-pair study of primary total hip arthroplasty, 45 all-polyethylene cemented acetabular components were compared with 45 cementless, hemispheric, titanium acetabular components. At 9 to 12 years, 1 of the cemented acetabular components was revised for aseptic loosening, and 14 (31%) were radiographically loose. Nine (20%) cemented acetabular components had pelvic osteolysis. In the cementless acetabular component group, 2 well-fixed components were revised. No components were radiographically loose, and 3 (7%) had pelvic osteolysis. Thirty-eight (97%) of the patients in each group were satisfied with the surgery. The clinical results of the cemented and cementless components were excellent. The cementless components had less loosening (P <.001) than the cemented components.

In most circumstances, NF-kappaB, which is essential for osteoclastogenesis, is activated following serine 32/36 phosphorylation of its cytosolic inhibitory protein, IkappaBalpha. In contrast to other cell types, IkappaBalpha, in bone marrow macrophages (BMMs), which are osteoclast precursors, is tyrosine-phosphorylated by c-Src kinase. To address the role of IkappaBalpha phosphorylation in osteoclastogenesis, we generated TAT fusion proteins containing wild-type IkappaBalpha (TAT-WT-IkappaB), IkappaBalpha lacking its NH(2)-terminal 45 amino acids (TAT-IkappaB(46-317)), and IkappaBalpha in which tyrosine residue 42, the c-Src target, is mutated into phenylalanine (TAT-IkappaB(Y42F)). TAT-IkappaB efficiently enters BMMs, and the NF-kappaB-inhibitory protein, once intracellular, is functional. While TAT-WT-IkappaB only slightly inhibits osteoclastogenesis, osteoclast recruitment is diminished >80% by TAT-IkappaB(46-317), an event mirrored by dentin resorption. The fact that TAT alone does not impact osteoclastogenesis, which also resumes following withdrawal of TAT-IkappaB(46-317), establishes that the mutant's anti-osteoclastogenic properties do not reflect toxicity. Affirming a functional role for IkappaB(Tyr(42)) in osteoclastogenesis, TAT-IkappaB(Y42F) is as efficient as TAT-IkappaB(46-317) in blocking osteoclast differentiation. Thus, dominant-negative IkappaBalpha constructs block osteoclastogenesis, and Tyr(42) is essential to the process, increasing the possibility that nonphosphorylatable forms of IkappaBalpha may be a means of preventing pathological bone loss.

Eighty-eight primary femoral reconstructions in 80 patients were performed with the Harris-Galante uncemented femoral stem by 1 surgeon between March 1984 and December 1987. Seventy-seven femoral components in 72 patients were followed for an average 126 months or until femoral revisions. The average age at operation was 54 years (range, 30-70 years). Fifty-two patients were men, and 20 were women. The present article documents the incidence of femoral osteolysis and femoral revision in this series of this type of femoral component at an average of 10 years. Fifteen femoral components (15 of 77, 19%) were revised, 14 (14 of 77, 18%) for aseptic loosening, osteolysis, or fracture through osteolysis. The remaining 62 femoral components were functioning well (average Harris Hip Score 89 points), but 7 (11%) were loose, and 32 (52%) had femoral endosteal lysis. Overall, 19 (25%) were revised or loose, and 46 (46 of 77, 60%) had lysis. The high incidence of femoral lysis and aseptic loosening with this early design of uncemented femoral stem continues to increase at 10-year follow-up.

One hundred and twenty-one primary hybrid total hip replacements were performed in 107 patients. A titanium, porous-coated, hemispherical acetabular component was fixed with screws, and a collared, chromium-cobalt femoral stem, with a roughened surface and a thin layer of methylmethacrylate on the proximal third, was inserted with contemporary cementing techniques (that is, use of a femoral medullary plug, a cement gun, and centrifugation and pressurization of the cement). Fifteen patients (fifteen hips) died before a minimum duration of follow-up of seven years, four patients (four hips) were too ill for a detailed follow-up examination at the time of the study, and two patients (two hips) refused to be evaluated at the time of the latest follow-up. None of these twenty-one hips had had a revision or a reoperation at the time of the latest follow-up. Eighty-six patients (100 hips) were available for clinical follow-up at an average of 120 months (range, eighty-four to 153 months) and for radiographic follow-up at an average of 118 months (range, eighty-four to 153 months). The average age of the patients at the time of the index arthroplasty was sixty-five years (range, forty-five to eighty-seven years). Three acetabular components were revised because of dissociation of the liner in association with a fracture of a locking tine. One well fixed acetabular component was revised because of pelvic osteolysis, and the femoral stem in the same patient was revised because of aseptic loosening. None of the ninety-six remaining acetabular components migrated, was classified as radiographically loose, or was revised because of aseptic loosening. Osteolytic lesions were identified adjacent to five acetabular components, and one of them was treated with bone-grafting around the well fixed acetabular shell. Two hips had a continuous radiolucent line at the interface between the acetabular implant and the bone. Three femoral stems had evidence of radiographic debonding (a radiolucent line that was one millimeter wide or less between the cement and the prosthesis), and they were classified as radiographically loose despite excellent clinical results. Seven hips had osteolytic areas located in the proximal aspect of the most proximal zones of Gruen et al., and five had small osteolytic regions in more distal areas. The Harris hip score for the eighty-two patients (ninety-six hips) who did not have a revision improved from 48 points (range, 22 to 70 points) preoperatively to 92 points (range, 53 to 100 points) at the most recent follow-up examination. Eighty-one patients had no, slight, or mild pain in the hip, and they were satisfied with the clinical result. In the present study, the hybrid total hip replacement with use of the Harris-Galante acetabular component and the Precoat femoral stem continued to provide an excellent result for most patients at an average of approximately ten years after the operation.

Two hundred and thirty-seven consecutive primary acetabular reconstructions were performed, in 213 patients, with use of a Harris-Galante porous-coated acetabular component with screw fixation between January 1984 and December 1987. Twenty-four patients (twenty-seven hips) died before a minimum duration of follow-up of eighty-four months, five patients (five hips) were too ill to return for a detailed follow-up examination at the time of the study, four patients (four hips) refused clinical and radiographic follow-up (but one of these patients had more than eighty-four months of follow-up for one side of a bilateral total hip replacement), two patients (two hips) were lost to follow-up, and two patients (two hips) refused radiographic follow-up but had adequate clinical follow-up. In addition, one patient who had had a bilateral total hip replacement had a resection arthroplasty on one side because of a late infection 115 months after the index procedure. Thus, 196 hips (83 per cent) in 177 patients were available for radiographic and clinical review after an average duration of follow-up of 122 months (range, eighty-four to 155 months). The average age of these 177 patients at the time of the operation was fifty-nine years (range, twenty-three to eighty-seven years). Eight well fixed acetabular shells (4 percent) were revised: three were revised because of dissociation of the liner in association with fractures of the tines, three were revised during revision of the femoral component, and two were revised because of retroacetabular osteolysis. In eight other hips, the acetabular liner was exchanged during revision of a loose femoral component. No acetabular component migrated, was classified as radiographically loose, or was revised because of aseptic loosening. There was no evidence of fragmentation or disruption of the titanium porous mesh of any cup. One of 528 screws broke. There were no complications associated with the insertion of the acetabular fixation screws. Osteolytic lesions were identified adjacent to nine (5 percent) of the 188 acetabular components that were in place at the time of the most recent examination. One hip, which had discontinuous osteolytic lesions in all three acetabular zones, was treated with bone-grafting around the well fixed acetabular component. Eight hips had a discontinuous radiolucent line that was 1.0 millimeter wide or less in all three zones and another two had a continuous radiolucent line that was 0.5 millimeter wide in all three zones. The average Harris hip score for the 188 hips (169 patients) that did not have revision of the acetabular shell improved from 47 points (range, 22 to 71 points) preoperatively to 89 points (range, 35 to 100 points) at the time of the latest examination. One hundred and thirty-four hips had an excellent result; twenty-six, a good result; nineteen, a fair result; and nine, a poor result. All nine hips that had a poor result were in patients who had other factors, unrelated to the acetabular component, that contributed to the low Harris hip score. In the present study, the Harris-Galante porous-coated acetabular component continued to provide excellent fixation and clinical results for most patients at an average of approximately ten years after the operation.

Quantification of argyrophilic nucleolar organizer regions has been proposed as a technique that may aid in diagnosing and predicting the biologic behavior of a variety of neoplasms. A 1-step silver staining technique was used to identify and quantify argyrophilic nuclear organizer regions in a series of 96 bone tumor specimens. Malignant bone tumors had a higher mean argyrophilic nuclear organizer region count (3.05 +/- 0.82) than giant cell tumors (1.39 +/- 0.14, p < 0.001) and benign bone tumors (1.51 +/- 0.42, p < 0.001). Despite these differences in mean counts, an overlap of argyrophilic nuclear organizer region scores was observed in some benign and malignant cases. The argyrophilic nuclear organizer region counts of the osteosarcomas were analyzed to determine whether they correlated with tumor behavior. The mean argyrophilic nuclear organizer region count of specimens from patients in whom metastatic disease developed was not significantly different than that of patients who remained disease free.

Between 1981 and 1990, twenty-two patients with incomplete neurologic deficits after thoracolumbar junction fractures were treated by anterior decompression and stabilization. Two patients were unavailable for follow-up examination, eleven underwent spinal canal decompression within 48 hours of injury (Group A); and nine patients underwent surgical decompression in an average of 61 days after injury (Group B). Neurologic recovery was analyzed by a modified Frankel grading system, the ASIA motor point scale and conus medullaris function. Patients were followed for an average of 3.5 years (range, 6-92 months). No patients had any deterioration in neurologic function after surgery. Patients in Group A had a modified Frankel grade improvement with a median of two grades and a mean American Spine Injury Association motor point improvement of 21.1 +/- 4.1. Four of nine patients with conus medullaris deficits demonstrated complete functional bladder and bowel return postoperatively. Those patients in Group B had a modified Frankel grade improvement with a median of one grade and a mean ASIA motor point improvement of 7.6 +/- 1.7. None of the six patients with conus medullaris injuries showed complete improvement in bladder or bowel function postoperatively. The modified Frankel grade and ASIA motor point score improvements were significant when the two groups were compared (P less than 0.04 and P less than 0.01, respectively). In this series of patients, early anterior decompression for traumatic injuries at the thoracolumbar junction was associated with improved rates of neurologic recovery when compared to late decompression.