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W H Harris

Publications and source records attributed to W H Harris.

At least 145 records · Page 8Linked to original sources
PubMed1993

High failure rate of bulk femoral head allografts in total hip acetabular reconstructions at 10 years.

The authors evaluated the radiographic appearance and functional performance of 30 cemented total hip arthroplasty acetabular reconstructions in 28 patients in whom bulk, weight-bearing, femoral head allografts were used to augment severe acetabular bone deficiency with a mean follow-up period of 10 years (range, 8-13.3 years). The average age of the patients was 51 years. The current study group represents the 10-year subset of a larger series of 38 hip reconstructions previously reported. The graft was bolted within the acetabulum in 12 hips and to the lateral wing of the ilium in the other 18 hips. On average, these grafts supported approximately 60% of the acetabular component. All grafts united. Failure of fixation of the acetabular component occurred in 47% of the acetabular reconstructions (14 hips in 14 patients). Four were diagnosed as loose on the basis of radiographic criteria alone and the other 10 hips had a loose acetabular component at reoperation. Loosening occurred in 58% (7 of 12) of the sockets with intraacetabular graft and in 40% (7 of 18) of those bolted to the lateral ilium. The failure rate of 47% in these reconstructions at 10 years is in sharp contrast to high success rates at less than 5 years and argues against the use of bulk weight-bearing allografts for most situations unless the only alternative is resection arthroplasty.

Acetabulum↗
PubMed1993

Autopsy studies of the bone-cement interface in well-fixed cemented total hip arthroplasties.

Although knowledge of the clinical status of the implant is important, only instrumented mechanical testing of retrieved specimens provides quantitative assessment of implant fixation. This measurement allows placement of the implant along a continuum of loosening and is the foundation for the interpretation of subsequent findings. Analysis of implants that have been proven to be well fixed by instrumented testing reveals significant differences in the initial events in the loosening of femoral and acetabular components. Although radiolucencies were observed around all of these well-fixed femoral and acetabular components, the histology (and therefore the etiology) of the radiolucency is different and variable on the two sides of the articulation. The majority of femoral radiolucencies appear to be due to age and stress-related remodeling while particulate-induced bone resorption plays an important role in acetabular radiolucencies. A finding common to both sides of the articulation in these stable components, however, was intimate contact of bone with cement without any interposed soft tissue even after 17.5 years of service. Primary incompatibility and/or failure of the cement was not identified as a factor in initiating either femoral or acetabular component loosening. These studies document the long-term compatibility of bone with cement in bulk form. Improvements in cemented femoral component fixation should focus on stem design and cementing technique. Long-term acetabular component fixation can be improved by reduction or elimination of polyethylene wear and optimization of the bone-implant interface.

Biocompatible Materials↗
PubMed1993

Hybrid total hip replacement. A 6.5-year follow-up study.

We have reviewed 97 consecutive primary hip replacements with a cemented femoral component and a porous-ingrowth acetabular component at a minimum five-year follow-up (average 6.5 years). The average Harris hip score was 93, and 85 hips had no pain or only slight pain. There had been no deterioration in the results since the two-year follow-up. The hybrid hip is successful for up to eight years and appears to be suitable for many patients. Long-term femoral fixation has been shown to improve with second-generation cementing techniques and in this series was excellent with third-generation techniques, in that only one stem was revised for loosening. No cementless acetabular component was revised for loosening.

Adult↗
PubMed1993

Complications related to modularity of total hip components.

We report complications from the use of modular components in 20 hip replacements in 18 patients. Fifteen complications (in 13 patients) were related to failure of a modular interface after operation. Femoral head detachment from its trunnion was seen in 6 hips from trauma (3), reduction of a dislocation (2), and normal activity (1). In one case the base of the trunnion fractured below an extra-long modular head. In seven other hips the modular polyethylene liner dislodged from its shell, causing severe damage to the shell in four cases with extensive metallosis. In one other hip an asymmetrical polyethylene liner rotated, resulting in impingement of the femoral component and recurrent dislocation. Operative errors were seen in five cases: implantation of a trial acetabular component in one; and mismatching between the size of the femoral head and the acetabular component in the others. Surgeons who use hip replacements with modular components should be aware of the potential for operative error and of the importance of early treatment for postoperative mechanical failure.

Adult↗
PubMed1993

The value of aspiration of the hip joint before revision total hip arthroplasty.

The role of aspiration of the hip joint before revision of a total hip arthroplasty remains controversial. To address this issue, we reviewed the results of 270 consecutive hips in which aspiration had been attempted before revision procedures that were performed between 1980 and 1988. All hips had intraoperative findings and clinical follow-up of at least two years to confirm the presence or absence of infection. Only six (2 per cent) of the 270 hips were determined to be infected. Aspiration had been attempted in all six hips, but fluid could be obtained from only four. All six hips also had clinical or radiographic signs, or both, of infection, including increasing pain within three years after the arthroplasty (four hips), inability of the patient to attain pain-free status after the original procedure (four hips), radiographic findings compatible with infection (six hips), and a positive finding on culture of a specimen obtained from a previous aspiration (two hips). Because of these factors, aspiration was attempted a second time in four of the six hips and a third time in three of the four. The four hips from which fluid could be obtained had a total of ten successful aspirations; the cultures of specimens obtained from six of these procedures were positive and those from four were negative. The appearance of the capsular tissue at the time of the operation suggested infection in five of the six infected hips. Histological sections were positive for inflammation in all six: there was acute inflammation only in one, chronic inflammation only in two, and acute and chronic inflammation in three. No organisms were seen on gram stains of specimens from any of the six infected hips. Of the 254 hips that did not have an infection and had been aspirated successfully, thirty-two (13 per cent) had a false-positive result on culture of a specimen of the aspiration fluid. Only two (6 per cent) of the thirty-four hips that had a positive result on culture of fluid from the initial aspiration had a true-positive result. No hip had a true-positive result on culture of fluid that had been aspirated preoperatively without also having clinical and radiographic evidence of infection. On the basis of these findings, we recommend that aspiration be performed in selected patients rather than routinely. It also should be performed only if a detailed clinical history suggests infection or if radiographs demonstrate focal lysis, aggressive non-focal lysis, or periostitis.

Aged↗
PubMed1993

Production of cytokines around loosened cemented acetabular components. Analysis with immunohistochemical techniques and in situ hybridization.

The chronic inflammatory response to wear particles from orthopaedic joint implants is believed to cause osteolysis and to contribute to prosthetic loosening. Previous in vitro experiments have demonstrated that particulate debris from joint implants causes cells in culture to release products that have been implicated in this pathological bone resorption. The purpose of the current study was to investigate the in vivo features of this complex process in patients who had had a total hip replacement. Membraneous tissue was obtained from the cement-bone interface of ten polyethylene acetabular components that had been revised for aseptic loosening in ten patients. The immunoperoxidase technique, which involves the use of specific antibodies for each cell type, showed that macrophages were the predominant cellular constituents but also that fibroblasts, many of which were not identified on plain histological study, were present and were actively producing collagen. T lymphocytes were present variably, but they generally composed less than 10 percent of the cells. Particulate debris (polyethylene, methylmethacrylate, and metal) was present in all membrane specimens but was intracellular only in macrophages and multinucleated giant cells. 35S-labeled nucleic-acid probes, complementary to human interleukin-1-beta and to platelet-derived growth-factor-2 messenger RNA (mRNA), were hybridized with serial tissue sections. Hybridization demonstrated interleukin-1-beta mRNA predominantly in macrophages, and not in fibroblasts or in T lymphocytes to any major extent. In contrast, immunolocalization demonstrated interleukin-1-beta protein on both macrophages and fibroblasts, suggesting that macrophages release interleukin-1-beta, which then binds to both fibroblasts and macrophages. Platelet-derived growth-factor transcripts were found in both macrophages and fibroblasts.

Aged↗
PubMed1993

Routine use of adjusted low-dose warfarin to prevent venous thromboembolism after total hip replacement.

The efficacy and safety of routine use of adjusted low-dose warfarin for twelve weeks--without sonography or venography--for the prophylaxis of deep-vein thrombosis after total hip replacement was assessed in 268 patients (134 men and 134 women) who were between the ages of forty and eighty-five years (average, sixty-one years). The patients were given warfarin orally both before and after the operation. The initial dose was usually ten milligrams on the night before the operation and five milligrams on the night after the operation. Thereafter, the dose was adjusted to keep the prothrombin time between fourteen and sixteen seconds. The control time was ten to twelve seconds. The partial thromboplastin time was also measured, and the dose of warfarin was reduced if the value was more than fifty seconds. All 268 patients continued to take low-dose warfarin for twelve weeks after the operation. There were 170 primary and ninety-eight revisional total hip-replacement operations. Thirty-four patients (13 per cent) had a history of thromboembolic disease or venous stasis in a lower limb. Neither phlebography nor sonography was done routinely. All of the patients were followed for six months after the operation. There were no fatal pulmonary emboli during the period of the study and no known pulmonary emboli after any patient was discharged from the hospital. Two non-fatal pulmonary emboli were identified, both during hospitalization. Ten patients (4 per cent) had an episode of major bleeding--a wound hematoma in nine and a gastrointestinal hemorrhage in one--during hospitalization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Histology of porous-coated acetabular components. 25 cementless cups retrieved after arthroplasty.

25 hemispherical acetabular components retrieved from patients who had a total hip arthroplasty (THA) were studied histologically. All of the components had titanium fiber metal porous coatings and were implanted with adjuvant screw fixation, 18 in primary THA and 7 in revision THA. None of the cups had been removed because of infection or failure of fixation. The components had been in place an average of 30 (1-140) weeks. 18 cups had bone ingrowth into the porous coating. Up to one third of the available void space within the porous coating was occupied by bone, while the maximal proportion of the area of the bone-implant interface with bone ingrowth was over 80 percent. Bone ingrowth was more often observed at the dome and in the vicinity of sites of screw fixation than elsewhere. Peripherally, bone ingrowth was less consistent, and in isolated areas fibrocartilage and mineralized fibrocartilage were occasionally observed. The longer-term cases had more bone ingrowth than the shorter-term cases. Apparent metallic debris was observed within histiocytes adjacent to screw holes, and the amount of this material increased with duration of implantation.

Acetabulum↗
PubMed1993

Bulk versus morselized bone graft in acetabular revision total hip replacement.

Use of bulk femoral head autografts and allografts as structural members in complete reconstruction of deficient acetabulae in total hip replacements is associated with a high failure rate after about 5 years. The failures are usually catastrophic requiring reoperations. The reoperation failure rate is eight times greater than those used in primary total hip replacement without structural bone grafting. Contemporary alternatives to bulk structural grafting involves the use of hemispherical, porous, cementless acetabular components fixed with screws and supplementary nonstructural bone grafting. These procedures have proven to be very successful over the short term, and it is hoped that they will provide results superior to those obtained with bulk femoral head allografts. There is also no need to use the bulk femoral head grafts to bring a high hip center down to the normal level.

Bone Screws↗
PubMed1993

High assembly strains and femoral fractures produced during insertion of uncemented femoral components. A cadaver study.

The assembly strains produced in cadaver femurs during uncemented femoral arthroplasty were measured using strain gages and photoelastic coatings. Resecting the femoral neck, reaming the canal with power drills, and rasping with an optimal size rasp, as determined by preoperative radiographic templating, produced small assembly strains, up to 300 microstrain. Insertion of an optimal-size prosthesis after preparing the femoral canal with instruments the same size as the prosthesis produced moderate assembly strains, up to 1,000 microstrain. Half a millimeter press-fit of optimal prostheses produced larger assembly strains, up to 2,000 microstrain. Half a millimeter press-fit of a prosthesis that was also one size (1.0 mm) larger than that determined to be optimum produced even larger assembly strains (2,000-6,000 microstrain) and longitudinal linear fractures in the femoral cortex. Insertion of prostheses that were smaller than the rasps produced minimal strains in the femoral cortex. The magnitude of peak strains produced by press-fitting the femoral components and the small amounts of disparity between the size of the recess and the prosthesis necessary to produce these strains show the narrow range of tolerances available to the surgeon. Cementless femoral arthroplasty requires great care in preparing the femoral canal to the appropriate size as determined from preoperative templating, using accurate and precisely toleranced instrumentation and prosthetic components in order to avoid femoral fractures, yet obtain a stable fit.

Adult↗
PubMed1993

Techniques of extraction of well-fixed cemented and cementless implants in revision total hip arthroplasty.

Removal of well-fixed cemented and cementless components in total hip arthroplasty is technically demanding and requires a multitude of surgical techniques and tools. The wide array of modular prostheses currently in use adds to the complexity of this task. The authors describe the several techniques that facilitate extraction of well-fixed cemented and cementless total hip prostheses, as well as the bone cement. A working knowledge of these techniques should result in easier implant extraction and less bone destruction during this process.

Acetabulum↗
PubMed1993

Contemporary algorithms for evaluation of the painful total hip replacement.

Current data on the interpretation of nuclear medicine scans following total hip replacement are reviewed along with a new diagnostic test--the dynamic computed tomographic scan. Intraoperative diagnostic tests include frozen section, Gram's stain, and mechanical testing. This information is consolidated with that previously presented into a series of algorithms for evaluating the painful total hip replacement.

Algorithms↗
PubMed1993

Effects of Pasteurella haemolytica culture supernate on bovine tracheal smooth muscle.

Pasteurella haemolytica leukotoxin is a ruminant specific leukotoxin that has been implicated in the pathogenesis of shipping fever in cattle. The present study was undertaken to determine the effect of this toxin on bovine airway smooth muscle. In vitro, the addition of culture supernate containing leukotoxin to bovine tracheal smooth muscle resulted in contraction of 55% of the muscle strips tested. Maximum responses were reached rapidly during cumulative additions of this material. In 95% of the muscle strips that responded, maximum responses were obtained after the addition of one or two cumulative doses. Repeated additions of culture supernate resulted in decreased responsiveness. Since responsiveness to other agonists was not affected, these results suggest the development of a condition similar to tachyphylaxis. The contractions were inhibited by antihistamines. Diphenhydramine, at a concentration of 10(-6) M (dose-ratio 7), and mepyramine, at a concentration of 2 x 10(-7) M (dose-ratio 56), blocked the contractions by 84% and 100% respectively. In addition, the contractions were blocked by the muscarinic antagonist atropine, but this inhibition was much weaker (46%) and was present at high concentrations only. Inhibition of the contractions by H1 receptor antagonists suggests that the contractions are mediated via H1 receptors. Since the dose-response relationship is not typical of a drug-receptor interaction, it appears unlikely that the leukotoxin is a direct agonist of H1 receptors. It is proposed that an indirect mechanism of action involving the release of histamine by tissue mast cells is responsible for the leukotoxin-induced contractions.

Animals↗
PubMed1993

Total hip replacement in the middle-aged patient. Contemporary cementing for fixation of the femoral component.

Important advances have been made in the preparation and use of cement and the design of femoral components. Additionally, we have a greater understanding of the biologic basis of osteolysis, previously considered a manifestation of 'cement disease.' The results now emerging as an outcome of modern cementing techniques and component designs represent a major step forward and raise serious doubts about the justification for cementless fixation of the femoral component, given the present state of the art.

Adult↗
PubMed1993

Management of the deficient acetabulum using cementless fixation without bone grafting.

Based on the extensive experience with bulk femoral head augmentation of the acetabulum that began in 1973 and the disturbing incidence of failure that has been substantial and progressive, it is argued that sufficient justification, apart from exceptional circumstances, for the use of this reconstructive technique no longer exist. Instead, technical and technologic advances in the use and design of components that stabilize by biointegration now offer a more attractive alternative.

Acetabulum↗