Search PubMed⌕ Search

Biomedical subjects

R B Greer

Publications and source records attributed to R B Greer.

At least 19 recordsLinked to original sources
PubMed1992

Open and arthroscopic synovectomy in hemophilic arthropathy of the knee.

Open and arthroscopic synovectomies of the knee in patients with classic hemophilia were evaluated with regard to effectiveness in reducing bleeding episodes, the effect on range of motion (ROM), and roentgenographic progression of hemophilic arthropathy. Eleven patients underwent 13 synovectomies (eight open, five arthroscopic). The average follow-up periods were 7.9 years and 2.2 years for the open and arthroscopic groups, respectively. Both procedures significantly reduced recurrent hemarthroses. Knee ROM in the open synovectomy group was decreased or unchanged in 75% and minimally increased in 25%, whereas there was an increased in 80% and a decrease in 20% of the knees in the arthroscopic group. Furthermore, 62.5% of the knees required manipulation to improve ROM in the open synovectomy group, versus 0% in the arthroscopic group. Hemophilic arthropathy progressed in most knees in both groups. The arthroscopic group had a longer operative procedure (122 versus 59 minutes), but required less hospitalization (9.4 versus 23.1 days) and 25.6% less Factor VIII replacement. Both techniques reduce hemarthroses. There is usually a net loss of ROM with the open versus a net gain with the arthroscopic procedure, and roentgenographic progression hemophilic arthropathy is slowed but not halted after synovectomy.

Adolescent↗
PubMed1992

Gerhard Domagk.

Explore the source record for details and available documents.

Bacteriology↗
PubMed1992

On fellowships.

Explore the source record for details and available documents.

Curriculum↗
PubMed1992

Role modeling.

Explore the source record for details and available documents.

Female↗
PubMed1990

Threaded acetabular components for primary and revision total hip arthroplasty.

A clinical and radiographic review of 48 total hip arthroplasty patients with threaded acetabular components was undertaken at 24-44 months of follow-up study. Twenty-five patients had primary hip arthroplasties and 23 had revision procedures. Clinical scores revealed good to excellent results in 60% of primary and 30% of revision procedures. Radiographic analysis revealed stable acetabular components in 88% of primary and 61% of revision procedures. Potentially loose acetabular components were noted in 8% of primary and 4.3% of revision procedures and loose acetabular components in 4% of primary and 34.7% of revision procedures. The rate of acetabular component loosening was considered unacceptably high in revision cases and an area of concern in primary cases. Discretionary use of these components is advised.

Acetabulum↗
PubMed1990

The association between students' research involvement in medical school and their postgraduate medical activities.

The authors examined the impact of students' research involvement during medical school on their postresidency medical activities. The three medical schools involved--The Pennsylvania State University College of Medicine (PSU), The University of Connecticut School of Medicine (UCONN), and The University of Massachusetts Medical School (UMASS)--have nearly indistinguishable applicant, matriculant, and curriculum profiles. However, at PSU a research project is a curriculum requirement for students who did not do medical research prior to entering medical school. Questionnaires were sent to all graduates from the classes of 1980, 1981, and 1982. A total of 567 graduates completed the questionnaires, an overall response rate of approximately 76%. Medical school research experience was reported by 83% (183) of the PSU graduates, 34% (52) of the UCONN graduates, and 28% (54) of the UMASS graduates. When compared on a school-by-school basis, the graduates from the three schools did not differ with respect to residency specialty training, fellowship training, academic appointments, career practice choices, or postgraduate research involvement. However, when all the graduates studied were examined as a single group, medical school research experience was found to be strongly associated with postgraduate research involvement.

Academic Medical Centers↗
PubMed1989

Total knee arthroplasty using the kinematic rotating hinge prosthesis.

Patients receiving a Kinematic Rotating Hinge total knee prosthesis with a 25-month minimum follow up were reviewed. A total of 46 patients and 54 knees were included in the study. A detailed clinical assessment was available on 38 knees. Twenty of these knees had primary arthroplasties performed with the Kinematic Rotating Hinge prosthesis and 18 knees had revision arthroplasty. Ninety-five percent of primary knees and 83% of revision knees caused no or mild pain postoperatively. Using the Brigham and Women's Hospital and Harvard Medical School knee rating system, 80% of primary knees and 61% of revision knees were rated as good to excellent. Using the criteria defined in this article, 90% of primary knees and 83% of revision knees were labeled as having a satisfactory result. Forty-five percent of primary components and 52% of revision components demonstrated lucent lines on radiographic review. Seven percent of primary knees and 20% of revision knees showed evidence of aseptic lucency progression in one or more zones. No radiographic evidence of aseptic loosening was noted in this review. Documented sepsis occurred in one primary knee and two revision knees. Patellar instability occurred in 21% of primary knees and 36% of revision knees, representing the major complication. The Kinematic Rotating Hinge prosthesis is intended for use in arthroplasty cases where there is functional absence of collateral ligament stability. This review suggests that a high percentage of satisfactory clinical results can be achieved with this prosthesis with long-term radiographic stability.

Activities of Daily Living↗
PubMed1988

Early vertebral trabecular bone loss in normal premenopausal women.

The precise timing for the onset of trabecular bone loss in women is a matter of controversy. To address this issue, we studied the relationship between age and vertebral trabecular bone density (measured by computed tomography) in 74 healthy premenopausal women from 18 to 48 years old. We also measured radial cortical bone density (by single photon absorptiometry) in 28 of these subjects. Trabecular bone density levels (milligrams per milliliter, mean +/- standard error of the mean, SEM) were significantly (p less than 0.05) higher in the second (178 +/- 8) and third (171 +/- 6) decades than in the fourth (158 +/- 4) or fifth (140 +/- 12) decades, and were inversely correlated with age (r = -0.39, p = 0.0006), diminishing at a rate of 1.3 mg/ml (0.73%) per year. Radial cortical bone density levels (grams per square centimeter) were similar in the third (0.711 +/- 0.021), fourth (0.721 +/- 0.012), and fifth (0.736 +/- 0.012) decades and were not related to age (r = 0.17, p = 0.39). We conclude that vertebral trabecular bone loss in women commences during or prior to the third decade. In contrast, radial cortical bone density does not decline during the premenopausal years.

Adolescent↗
PubMed1988

Effect of declining renal function on bone density in aging women.

The factors that are responsible for trabecular bone loss in aging women are not completely understood. To evaluate declining renal function as a possible factor, we studied 19 Caucasian women (average age 67) who were from 6 to 41 years postmenopausal. Trabecular bone density was quantitated by computerized tomography of the spine. Serum calcium, phosphorus, and creatinine were normal in all subjects. Creatinine clearance averaged 74 ml/min (range 38-122), decreased with age (r = -0.60, P = 0.003), and was inversely related to serum creatinine (r = -0.51, P = 0.01). Bivariate regression demonstrated that bone density decreased with age (r = -0.59, P = 0.004); controlling for the effect of creatinine clearance weakened this correlation to r = -0.45 (P = 0.03); controlling additionally for 1,25-dihydroxyvitamin D [1,25(OH)2D] and parathyroid hormone (PTH) reduced the correlation coefficient to r = -0.34 (P = 0.11). Bone density also decreased in direct proportion to the decrement in creatinine clearance (r = 0.44, P = 0.03); controlling for the effects of 1,25(OH)2D and PTH reduced this correlation coefficient to r = 0.34 (P = 0.11). These results suggest that occult renal insufficiency may contribute to bone loss in aging women, and that this effect may be mediated in part by 1,25(OH)2D and PTH. In this age group renal function should be assessed by measuring creatinine clearance rather than the serum creatinine concentration since renal insufficiency can be masked by apparently normal circulating creatinine levels.

Aged↗
PubMed1988

Determinants of atraumatic vertebral fracture rates in menopausal women: biologic v mechanical factors.

In menopausal women, the susceptibility to atraumatic vertebral fractures is thought to be governed by both mechanical factors (as represented by bone density) and by biologic factors such as age, body size, and dietary calcium. Whether these biologic factors independently influence fracture rates beyond the effect of bone density is a matter of controversy. To compare the relative importance of mechanical and biologic factors on vertebral fractures, we elucidated the determinants of atraumatic compression fractures in 63 menopausal women who had no chronic diseases other than osteopenia. Trabecular bone density was determined by quantitative computerized tomography of the spine. Fracture frequency was expressed as the number of compressed vertebrae per person between T5 and L4. The analysis showed that fracture frequency, bone density, and the biologic factors were closely interrelated. Fracture frequency was inversely correlated to bone density [R2 (spline model) = .40, P less than .0001], body size (r = -.26, P = .05), and dietary calcium (r = -.28, P = .04), and directly correlated with age (r = .46, P = .0002). Bone density decreased with age (r = -.65, P less than .0001), increased with body size (r = .37, P = .004), and tended to increase with dietary calcium (r = .24, P = .08). After controlling for bone density, there was no perceptible residual relationship between fracture frequency and any of these biologic factors. We conclude that mechanical factors overshadow age, body size, and dietary calcium as determinants of vertebral fracture frequency. The apparent influence of these biologic factors on fracture frequency is explained by their surrogate effects on bone density.

Aged↗
PubMed1988

Should the patella be resurfaced in total knee arthroplasty? Efficacy of patellar resurfacing.

To assess the long-term efficacy of patellar resurfacing, 100 knees were evaluated in 84 patients. The operations were performed between 1978 and 1982. The follow-up period ranged from 60 to 103 months. The diagnosis was degenerative joint disease (DJD) in 83%, rheumatoid arthritis in 12%, and miscellaneous in 5% of the knees. The implant (47 knees) and nonimplant (53 knees) groups were comparable with respect to age, body size, and length of follow-up period. The analysis revealed equivocal results. Considering all diagnostic categories combined, rest pain was marginally better in the resurfaced group (p = 0.04), but this difference resulted from an unequal distribution of subjects between mild and zero pain categories. Pain with walking, maximum walking distance, ability to climb stairs and rise from a chair, active arc of motion, extensor lag, and quadriceps strength were similar in the two groups. When the DJD group was considered separately, no significant difference emerged. There was little evidence to support a recommendation for routine patellar resurfacing in total knee arthroplasty.

Activities of Daily Living↗
PubMed1988

A comparison of the risk of vertebral fracture in menopausal osteopenia and other metabolic disturbances.

The risk of atraumatic compression fracture in postmenopausal women increases as vertebral trabecular bone density decreases. To determine whether the risk is similar for patients who have other metabolic disorders, we compared eight-nine patients who had various disturbances affecting bone and sixty-three postmenopausal women who had no evidence of underlying disease. Trabecular bone density was measured by quantitative computed tomography of the lumbar spine. The relationship between frequency of fracture and bone density was modeled mathematically with spline threshold, quadratic polynomial, and decaying exponential functions. Analysis of covariance showed that the diagnostic category did not influence the relationship between frequency of fracture and bone density in any of the three models. We concluded that the risk of atraumatic compression fracture, as assessed by measurement of vertebral trabecular bone density using quantitative computerized tomography, is independent of the underlying metabolic disturbance.

Adult↗
PubMed1987

AML bipolar arthroplasty for degenerative hip arthritis.

Primary total hip arthroplasty using an uncemented AML porous coated femoral component and a bipolar acetabular component was performed on 50 consecutive patients with degenerative arthritis. Of the 50 patients, 43 (48 hips) were available for review at 2 to 3 years follow up. The data obtained in this review suggest that total hip arthroplasty using this prosthesis provides a consistently reliable hip replacement with few related complications and a high patient satisfaction rate. A stable radiographic appearance of both the femoral and acetabular components can be expected.

Acetabulum↗
PubMed1987

Assessment of the risk of vertebral fracture in menopausal women.

The decision to institute prophylaxis in women with menopausal osteopenia is hampered by the absence of quantitative criteria for appraising the risk of fracture in the individual. We have developed standards for assessing the risk of fracture by relating the prevalence of atraumatic vertebral compression fractures to bone density in sixty-five menopausal women, forty-nine to ninety-two years old. To define the upper limit of the spectrum of bone density, we also studied thirty-one young women, seventeen to twenty-two years old. The density of trabecular bone in a vertebral body was determined by quantitative computed tomography and expressed in terms of milligrams per milliliter of dipotassium hydrogen phosphate. Twenty-five of the menopausal women exhibited at least one fracture (range, one to six fractures), and forty had no fracture. The bone density ranged from -9 to sixty-nine milligrams per milliliter in those with fractures and from twelve to 122 milligrams per milliliter in those without a fracture. The densities in the young women averaged 173 milligrams per milliliter and ranged from ninety-five to 248 milligrams per milliliter. The percentage of subjects with fractures increased as the bone density decreased. It was zero per cent in women with a density of seventy milligrams per milliliter or more, 38 per cent in women with a density between fifty and less than seventy milligrams per milliliter, 71 per cent in those with a density between thirty and less than fifty milligrams per milliliter, and 82 per cent in women with a density of less than thirty milligrams per milliliter.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗