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F Dorey

Publications and source records attributed to F Dorey.

At least 19 recordsLinked to original sources
PubMed1997

The efficacy of prophylaxis with low-dose warfarin for prevention of pulmonary embolism following total hip arthroplasty.

The selection of a prophylaxis regimen and its implementation have been influenced considerably by the decreased duration of hospital stays and the pressures of cost containment. The purpose of the present study was to determine the rate of symptomatic pulmonary embolism both before and after discharge, the number of days required to achieve an adequate level of anticoagulation, and the complications associated with the use of low-dose warfarin after total hip arthroplasty. Between 1987 and 1993, 1099 primary and revision total hip arthroplasties were performed in 940 patients who received low-dose warfarin for prophylaxis against thromboembolic disease. The average duration of prophylaxis was fifteen days (range, one to twenty-nine days). The target level of anticoagulation (as indicated by a prothrombin time of fourteen to seventeen seconds) was achieved an average of three days (range, one to sixteen days) after the operation. The level of anticoagulation was lower than the target range at the time of discharge after 257 total hip arthroplasties (23.4 per cent), and the target level was never achieved during the period of hospitalization after fifty-four such procedures (4.9 per cent). Twelve total hip arthroplasties were associated with a symptomatic pulmonary embolism; the over-all prevalence of this complication therefore was 1.1 per cent (95 per cent confidence interval, 0.4 to 1.9 per cent). Four pulmonary emboli were diagnosed before discharge and eight, after discharge. A fatal pulmonary embolism occurred after one procedure (0.1 per cent). Patients who had a history of symptomatic venous thromboembolic disease had a significantly increased risk of symptomatic pulmonary embolism after total hip arthroplasty (p = 0.001, Fisher exact test). A major bleeding episode occurred after thirty-two total hip arthroplasties (2.9 per cent). Patients who had a prothrombin time of more than seventeen seconds had a significantly increased risk of hematoma formation (p = 0.003, chi-square analysis). Prophylaxis with low-dose warfarin is safe and effective for the prevention of pulmonary embolism after total hip arthroplasty.

Adult↗
PubMed1996

Wear and morphology of ultra-high molecular weight polyethylene wear particles from total hip replacements.

The wear rate of ultra-high molecular weight polyethylene total hip replacement components is known to be influenced by various factors such as material and design. However, it is not known if these factors affect the size or morphology of the wear particles. The aim of this study was to compare the polyethylene wear particles from hip replacements of differing bearing materials and designs. Tissues were obtained at the revision surgeries of patients with surface replacements with titanium alloy or cobalt-chrome alloy femoral components up to 51 mm in diameter, and stem-type hip replacements with cobalt-chrome or alumina ceramic femoral components that were 28 or 32 mm in diameter. The polyethylene particles were isolated following tissue digestion and density gradient separation, and then studied by scanning electron microscopy. A computerized image analysis system was used to measure the diameter and length of the particles. The majority of wear particles were submicron in diameter. No systematic differences in size and morphology were found between the groups in this study. The similarity in size and morphology of the wear particles suggested that the same basic wear mechanisms were occurring in these components.

Adult↗
PubMed1996

Differences between patients' and physicians' evaluations of outcome after total hip arthroplasty.

The purpose of this study was to compare patients' and physicians' evaluations of the results of 147 total hip arthroplasties. The patients and physicians independently evaluated pain and over-all satisfaction with the outcome of the procedure using a 10.0-centimeter visual-analog scale. They also answered a questionnaire with which they assessed general health, functional ability, and pain. The mean (and standard deviation) analog rating for pain (with 0.0 centimeters indicating no pain and 10.0 centimeters, severe pain) was 1.7 +/- 2.6 centimeters as assessed by the patients and 1.1 +/- 1.8 centimeters as assessed by the physicians (p < 0.001, paired t test). The mean analog rating for over-all satisfaction (with 0.0 centimeters indicating poor and 10.0 centimeters, excellent) was 8.6 +/- 2.1 centimeters as assessed by the patients and 8.8 +/- 1.7 centimeters as assessed by the physicians (p = 0.07, paired t test). There was a marked disparity between the patients' and the physicians' scores when the patients assigned a low score to a particular area. For the thirty patients who rated the pain as more than 4.0 centimeters, the mean analog rating was 6.8 +/- 2.1 centimeters according to the patients, while it was 3.6 +/- 2.7 centimeters according to the physicians (p < 0.001, linear regression). The mean analog rating for over-all satisfaction according to the nineteen patients who rated this parameter as less than 7.0 centimeters was 3.8 +/- 2.0 centimeters, while the mean rating according to the physicians 6.5 +/- 2.8 centimeters (p < 0.001, linear regression). The patients' and physicians' evaluations were similar regarding the results of the total hip arthroplasty when the patients had little or no pain and were satisfied with the result. However, the disparity increased as the patients' ratings for pain increased and their ratings for over-all satisfaction decreased. This study highlights a discrepancy between patients' and physicians' evaluations of the results of total hip arthroplasty. This discrepancy increased when the patient was not satisfied with the outcome. The use of patients' self-administered questionnaires as well as traditional physician-generated assessments may provide a more complete evaluation of the results of total hip arthroplasty.

Activities of Daily Living↗
PubMed1996

Quantitative polymerase chain reaction does not improve preoperative prostate cancer staging: a clinicopathological molecular analysis of 121 patients.

PURPOSE: To improve on current staging and monitoring methods for prostate cancer, we applied the technique of quantitative polymerase chain reaction to measure the degree of tumor burden in the circulation and correlate this with pathological tumor stage. A reproducible, highly sensitive and specific, reverse transcriptase-polymerase chain reaction amplification technique to quantify prostate specific antigen (PSA) and prostate specific membrane antigen gene expression in the peripheral circulation was developed. Using a 32phosphorus-gamma-adenosine triphosphate-5'PSA and prostate specific membrane antigen primer incorporation assay, the ribonucleic acid signal extracted from a single neoplastic cell (LNCaP) premixed in 10 cc normal whole blood could be amplified. PSA and prostate specific membrane antigen polymerase chain reaction indexes have been created for clinical application. MATERIALS AND METHODS: From September 1994 through July 1995 specimens from 121 patients were prospectively analyzed for PSA and prostate specific membrane antigen signals. RESULTS: Circulating PSA producing cells were present in 29 of 33 patients (88%) with metastatic prostate cancer. Two of 19 patients (11%) with no known prostate cancer exhibited positive signals (1 later had prostate cancer), establishing a sensitivity of 88% and specificity of 94% for our assay. Positive PSA polymerase chain reaction signals were detected in 30 of 51 patients (59%) with stages pT1 and pT2 disease and in 13 of 18 (72%) with stage pT3 cancer. No statistically significant relationship of a positive PSA polymerase chain reaction signal to pathological stage, tumor grade, apical involvement or positive surgical margins was found, and no benefit was derived by measuring the quantity of circulating PSA polymerase chain reaction signals. Circulating prostate specific membrane antigen polymerase chain reaction signals were identified mostly in patients with advanced prostate cancer and offered no benefit to preoperative staging. CONCLUSIONS: Given the high incidence of false positive signals in patients with pathologically determined localized disease, in our experience polymerase chain reaction based assays offer no immediate benefit for preoperative prostate cancer staging. The prognostic significance of detecting circulating prostate specific signals awaits longer followup in this cohort of patients, which is currently under study.

Antigens, Neoplasm↗
PubMed1995

Endoprostheses for osteonecrosis of the femoral head. A comparison of four models in young patients.

Eighty-eight hip arthroplasties were carried out in 75 patients, all aged 50 years or less, with osteonecrosis. All the operations were carried out by one surgeon. Four different methods were used: a standard cemented arthroplasty; a cemented THARIES surface replacement; an uncemented surface replacement; a cemented titanium femoral surface hemiarthroplasty. Comparable clinical improvement occurred in all 4 groups initially. Aseptic loosening, with intersurface degradation and osteolytic lesions, was the most common cause of failure in the 3 types which had a polythene bearing. Polyethylene is the major contributor to bone loss around the endoprosthesis and loosening. Fixation of the surface hemiarthroplasty remained intact in every patient and failure was secondary to wear of the acetabular cartilage. We recommend surface hemiarthroplasty as an interim solution for young patients with stage III or early stage IV osteonecrosis because this procedure conserves bone stock, there is little osteolysis and it can easily be revised.

Adolescent↗
PubMed1995

Total femoral endoprosthetic reconstruction.

Twenty-one consecutive total femoral replacements performed at 2 institutions were reviewed. The surgical indications varied and included bone loss caused by tumor resections (12 patients), failed prior massive partial femoral endoprostheses (6 patients, 5 of whom had prior tumor resections), or difficult to treat fractures and nonunions (3 patients, 2 of whom had prior endoprostheses). Two patients with tumors died within 2 months. The results in the 19 longer-term survivors were satisfactory in 16 patients (good in 7, fair in 9) and poor in 3. Although not commonly used, when this method was indicated it provided an option to hip disarticulation, which often was the only other viable option. Age was the prime determinant of clinical outcome. Average active hip and knee range of motion was better in younger patients (< 60 years old, 66 degrees and 81 degrees, respectively) than in older patients (> or = 60 years old, 43 degrees and 49 degrees, respectively). All household ambulators required walkers and had a mean age of 81 years; community ambulators requiring 1 cane had a mean age of 46 years; and community ambulators using no walking aids had a mean age of 22 years.

Adolescent↗
PubMed1994

The incidence and significance of detectable levels of serum prostate specific antigen after radical prostatectomy.

A total of 601 patients who underwent radical retropubic prostatectomy for localized prostate cancer at our institution was followed with serial prostatic specific antigen (PSA) determinations. Three separate groups were delineated by pathological stage: 293 patients with organ confined disease, 215 with involvement of the capsule or positive margins and 93 with extension to the seminal vesicles. Followup ranged from 12 to 237 months (median 34). Five and 10-year disease-free survival rates for the 601 patients were 86 +/- 2% and 78 +/- 3%, respectively. The rate of detectable PSA (greater than 0.4 ng./ml.), used as an indicator of cancer progression, revealed 5 and 10-year disease-free rates of 69 +/- 2% and 47 +/- 3%, respectively. When comparing the patients from an earlier series to those who underwent surgery after 1986, an improvement in the 5-year clinical disease-free rate was noted (78 +/- 2% versus 93 +/- 2%, respectively). Similarly, an improvement in the 5-year disease-free survival rate with nondetectable PSA level was demonstrated in our contemporary series (80 +/- 3%) compared to our historical series. Of the 601 patients 123 had a detectable post-prostatectomy PSA level with or without clinical evidence of metastasis. A PSA doubling time before onset of adjuvant therapy was determined in 94 patients. Post-prostatectomy PSA doubling times were significantly different when comparing the patients who ultimately had progression to distant metastases (median 4.3 months) to those with either clinical local recurrence or a PSA elevation as the sole indicator of recurrence (median 11.7 months). Radical retropubic prostatectomy, whether assessed by clinical or biochemical means, has demonstrated excellent disease-free survival rates, especially since the advent of PSA and anatomical radical prostatectomy.

Adult↗
PubMed1994

Pulmonary metastases of stage IIB extremity osteosarcoma and subsequent pulmonary metastases.

PURPOSE: This study investigated prognostic factors in nonmetastatic high-grade extremity osteosarcoma and the prognosis following resection of subsequent pulmonary metastases, with emphasis on the effect of chemotherapy-induced tumor necrosis. PATIENTS AND METHODS: We reviewed 111 consecutive patients with high-grade nonmetastatic extremity osteosarcoma treated with preoperative chemotherapy and surgical resection, with additional review of 36 patients who had subsequent pulmonary metastases resected. RESULTS: The overall 5-year survival rate was 53%. In resected primary tumors, tumor-free resection margin (P < .001) and increasing chemotherapy-induced tumor necrosis (> 90% threshold, P < .003) correlated with increased metastasis-free survival. Relative risk factors for metastases were as follows: tumor-containing resection margin (most likely to metastasize); poor response to preoperative chemotherapy and/or lack of postoperative chemotherapy (next worse prognosis); and excellent response to preoperative chemotherapy (> or = 90% necrosis) combined with postoperative chemotherapy (best prognosis). The 5-year survival rate following pulmonary metastasis resection was 23%, whereas a 0% 4-year survival rate followed development of bony metastases (P < .001). The extent of tumor necrosis in resected pulmonary metastases did not affect prognosis. Survival was best in patients with three or fewer pulmonary nodules (P < .048), four or fewer recurrent pulmonary nodules (P < .047), unilateral pulmonary metastases (P < .037), or longer intervals between primary tumor resection and metastases (P < .082). CONCLUSION: Intensive preoperative and postoperative chemotherapy combined with complete resection of both primary and metastatic pulmonary osteosarcomas is justified, with a goal of 100% tumor necrosis and excision. Although current treatment regimens allow effective salvage therapy for a few patients with pulmonary metastases, more effective systemic treatment is needed.

Adolescent↗
PubMed1994

Anterior cruciate ligament tear. A new diagnostic index on magnetic resonance imaging.

An objective index of anterior cruciate ligament (ACL) tears based on posterior cruciate ligament (PCL) shape has been introduced. The PCL shapes on magnetic resonance imaging (MRI) were measured in 67 patients (31 normal ACL, 31 torn ACL, and five partial ACL tears, all confirmed by arthroscopy). All of the measurements were performed in a blinded manner, without previous knowledge of the MRI or arthroscopy diagnosis. The index consisted of the ratio B/A, with B equaling the length of the line between the posterior inferior tibial and the superior anterior femoral attachment of the PCL, and A equaling the maximum perpendicular distance from this line to the PCL. All measurements were performed twice, and the mean was used for statistical significance. The average index ratio was 5.4 and 3.9 for normal ACL and torn ACL, respectively. Using a cutoff value of 4.75, the sensitivity of the index was 87% and the specificity was 84%. An objective and reproducible index measurement of PCL shape for normal and injured ACL has been established. It provides additional information for both orthopaedic surgeons and radiologists in the diagnosis of ACL injury.

Adolescent↗
PubMed1993

Collagenase versus placebo in the treatment of Peyronie's disease: a double-blind study.

We investigated 49 men with Peyronie's disease in a prospectively randomized placebo controlled double-blind study, comparing the effects on plaque size and penile deformity of intralesional purified clostridial collagenase and saline placebo. For the group as a whole, treatment out-performed placebo (p < 0.007). When patients were analyzed with respect to disease severity, those with lesser deformity responded more favorably to treatment. The absolute angular change in patients responding to treatment was small. No significant side effects were noted within a 3-month followup.

Collagenases↗
PubMed1992

Adjuvant radiotherapy in patients post-radical prostatectomy with tumor extending through capsule or positive seminal vesicles.

Between 1976 and 1989, 115 patients at UCLA had radical retropubic prostatectomy for clinically localized prostate cancer with positive surgical margins, penetration of tumor into or through the capsule, or positive seminal vesicles. Twenty-four of those received adjuvant radiotherapy after having recovered from surgery. Complications of adjuvant treatment were uncommon and included urethral strictures in 3 patients and transient leg edema in 1. No patient in this group has had proved clinical disease progression though 6 have isolated detectable serum prostate-specific antigen (PSA) values. Clinical disease-free survival at five and seven years was 92 percent. If detectable PSA is also considered as evidence of tumor recurrence, the corresponding disease-free survival rates were 75 percent at five years and 54 percent at seven years. The 91 patients who received no postoperative radiotherapy had a clinical disease-free survival of 67 percent at five years and 56 percent at seven years. Disease-free survival drops to 43 percent and 24 percent, respectively, if detectable follow-up PSA is considered an indicator of disease progression. The comparisons of the survivorship curves in this retrospective study for the two treatment groups are statistically significant both for disease-free survival (p = 0.041), and disease-free survival with undetectable PSA (p = 0.043). Adjuvant radiotherapy has a beneficial effect after radical prostatectomy in patients with local tumor extension.

Aged↗
PubMed1992

Prostate specific antigen levels after radical prostatectomy in patients with organ confined and locally extensive prostate cancer.

A total of 230 patients with localized prostate cancer underwent radical retropubic prostatectomy at UCLA (pathological stage T1-3 N0, M0). Classification into groups included 115 patients with organ confined disease (group 1), 82 with invasion into or through the capsule (group 2) and 33 with seminal vesicle involvement (group 3). Median followup was 48 months. The 10-year, cause-specific survival was 96%, 90% and 63%, and 5-year, clinical, disease-free survival was 91%, 79% and 58% for the 3 groups, respectively. Recent prostate specific antigen (PSA) levels were measured in most patients, even those operated upon many years ago. Of the patients 41 had detectable (0.4 ng./ml. or greater) PSA levels without any other clinical evidence of progression and 15 with clinical evidence of progression had PSA levels in the detectable range at the time of clinical progression. When isolated detectable PSA was also considered an indicator of progression the 5-year and 10-year, disease-free rates were 61% and 41%, respectively. These data show that radical prostatectomy performed in patients with even microscopic invasion into the capsule, positive margins and seminal vesicle involvement is associated with a higher clinical progression rate than organ confined disease. If isolated detectable PSA is also considered an indicator of recurrence the disease-free survival after radical prostatectomy might be less than indicated by previous studies. The relationship among survival, local tumor extension and PSA must be carefully examined.

Adult↗
PubMed1992

Arthroplasty of the first metatarsophalangeal joint with a double-stem silicone implant. Results in patients who have degenerative joint disease failure of previous operations, or rheumatoid arthritis.

Sixty-six patients who had a total of eighty-six double-stem silicone implants in the first metatarsophalangeal joint were followed prospectively for an average of 5.8 years (range, two to fifteen years). There were two groups of patients: thirty-four patients (thirty-seven implants) who had degenerative joint disease (including those who had hallux rigidus or in whom a previous operation on a bunion had failed) and thirty-two patients (forty-nine implants) who had rheumatoid arthritis. The implants were used only if the patient was a candidate for an excisional arthroplasty or an arthrodesis; they were not used in patients who wished to maintain or adopt very active use of the foot (such as in running, jogging, and tennis) or to wear very high heels. Twenty-eight (82 per cent) of the thirty-four patients in the first group were completely satisfied and three (9 per cent) were somewhat satisfied. However, three patients (9 per cent), all of whom had had a failed bunionectomy, were dissatisfied; the ages of these three patients were less than the average age of all patients in the first group. Radiographs showed a fracture in three implants, but the patients had a good clinical result and an additional operation was not warranted. Twenty-seven (84 per cent) of the thirty-two patients in the second group were completely satisfied, four (13 per cent) were somewhat satisfied, and one (3 per cent) was dissatisfied. Radiographs showed a fracture in five implants. Four of the implants caused no symptoms, and the result was good; the fifth one was fragmented and was removed because of symptoms. Radiographs showed radiolucent areas around the implant and hypertrophic changes in many patients. There was no evidence of synovitis, such as that caused by silicone, either clinically or radiographically. We found that the double-stem silicone implant was effective in reconstructing the first metatarsophalangeal joint but emphasize our belief that it should be used only in carefully selected patients.

Adult↗
PubMed1991

Total knee arthroplasty using the total condylar III knee prosthesis.

Twenty-seven total knee arthroplasties (TKAs) were performed in 24 patients using the total condylar III knee prosthesis (TCP III) and were evaluated clinically and radiographically with a mean follow-up period of 4 years. Eighteen were revision TKAs, and nine were primary knee arthroplasties. Evaluations were made using the Hospital for Special Surgery (HSS) knee scale as well as the Knee Society radiographic evaluation method. Clinical results for all knees were 11% (3 of 27) excellent, 70% (19 of 27) good, 15% (4 of 27) fair, and 4% (1 of 27) poor. The one poor rating resulted from an intraoperative vascular injury. The results showed no statistical difference between revision and primary TKA. After operation, pain relief, range of motion, walking, function, and activity level improved in both the primary and revision patients. Radiolucencies 2 mm or greater in width were found in 6 of the 27 tibial components, in none of the 27 femoral components, and in 1 of the 19 patellar components. Only two tibial implants showed progressive radiolucencies. No correlation was found between the radiographic position of the implants and the clinical results. The authors conclude that the TCP III is a satisfactory choice for TKA in selected knees in which there is significant instability and in which intramedullary fixation is required.

Adult↗
PubMed1991

Prostatic specific antigen related to clinical status 1 to 14 years after radical retropubic prostatectomy.

Serum prostatic specific antigen (PSA by Tandem-R immunoassay) was measured in 190 patients after radical prostatectomy for prostate cancer. Serial measurements were made in all patients operated on in the past 3 years; 131 had undetectable levels and 59 had levels in the detectable range. Only 10% of the patients with undetectable PSA following surgery had seminal vesical involvement or positive lymph nodes. None of the patients with undetectable PSA have had clinical recurrence within the 41 months of mean follow-up. In 14 patients who had PSA serially measured since surgery, detectable levels were found within 6 months of operation and 7 of these patients had clinical progression within 2 years; 39 patients had detectable PSA after radical prostatectomy with no clinical evidence of recurrence. Biopsy of the anastomosis was performed in 11 patients with isolated detectable PSA after surgery and local recurrence was established in 4. PSA was detectable later in the follow-up of 45 patients operated on before the PSA assay became available but the date when PSA actually became detectable is not known. A relatively new method of estimating that date and constructing a corresponding Kaplan Meier curve is presented. PSA is an effective marker for monitoring patients after radical prostatectomy as it often detects early persistent disease in patients with detectable measurements 6 months post-operatively or recurrent disease in patients with later rising levels.

Aged↗