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Abstract
A prospective cohort study was undertaken to determine calf-level factors that affected calf health status between birth and 6 months of age. A convenience sample of approximately 3300 female Holstein calves born in 1991 on two large Florida dairy farms was used for the study. Data collected on each calf at birth included farm of origin, weight, height at the pelvis, birth date, and serum total protein (a measure of colostral immunoglobulin absorption). Birth season was dichotomized into summer and winter using meteorological data collected by University of Florida Agricultural Research Stations. Health data including date of initial treatment and number of treatments were collected for the diseases diarrhea, omphalitis, septicemia and pneumonia. All calves were followed for 6 months. Cumulative incidences of mortality and occurrence of diarrhea, omphalitis, septicemia and pneumonia were 0.12, 0.35, 0.11, 0.24 and 0.21, respectively. Serum total protein (TP) was a significant risk factor for mortality. The association of TP and mortality was quadratic and showed a dramatic decrease in mortality as TP increased from 4.0 to 5.0 g/dl, a small improvement from 5.0 to 6.0 g/dl and virtually no improvement in mortality rates as TP increased over 6.0 g/dl. The hazard mortality ratio was constant from birth to six months, indicating that the increased risk of mortality associated with low levels of TP was evident through six months of age. No interactions between TP, farm, season, or birth weight were found in these analyses. Serum total protein concentration was a significant risk factor for the occurrences, age of onset and severity of septicemia and pneumonia. The association between TP and septicemia was linear and an interaction with birth season was found. The association between TP and pneumonia was quadratic, and in contrast to the TP-and-septicemia relationship, the morbidity hazard ratio for pneumonia was not constant over the time measured; that is, colostral immunity protected the calf from developing pneumonia early in life, but this effect disappeared as the calf got older. Total protein was not a significant risk factor for diarrhea or omphalitis.
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Affiliation(s)
- G A Donovan
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-0136, USA.
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2
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Abstract
A prospective cohort study was undertaken to determine calf-level factors that affect performance (growth) between birth and 14 months of age in a convenience sample of approximately 3300 female Holstein calves born in 1991 on two large Florida dairy farms. Data collected on each calf at birth included farm of origin, birth date, weight, height at the pelvis, and serum total protein (a measure of colostral immunoglobulin absorption). Birth season was dichotomized into summer and winter using meteorological data collected by University of Florida Agricultural Research Stations. Data collected at approximately 6 and 14 months of age included age, weight, height at the pelvis, and height at the withers. Growth in weight and stature (height) was calculated for each growth period; growth period 1 (GP1) = birth to 6 months, and growth period 2 (GP2) = 6 to 14 months. Health data collected included data of initial treatment and number of treatments for the diseases diarrhea, omphalitis, septicemia, pneumonia and keratoconjunctivitis. After adjusting for disease occurrence, passive transfer of colostral immunoglobulins had no significant effect on body weight gain or pelvic height growth. Season of birth and occurrence of diarrhea, septicemia and respiratory disease were significant variables decreasing heifer growth (height and weight) in GP1. These variables plus farm, birth weight and exact age when '6 month' data were collected explained 20% and 31% of the variation in body weight gain and pelvic height growth, respectively, in GP1. The number of days treated for pneumonia before 6 months of age significantly decreased average daily weight gain in GP2 (P < 0.025), but did not affect stature growth. Treatment for pneumonia after 6 months of age did not significantly affect weight or height gain after age 6 months. Neither omphalitis nor keratoconjunctivitis explained variability in growth in either of the growth periods.
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Affiliation(s)
- G A Donovan
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-0136, USA.
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Fischgrund JS, Mackay M, Herkowitz HN, Brower R, Montgomery DM, Kurz LT. 1997 Volvo Award winner in clinical studies. Degenerative lumbar spondylolisthesis with spinal stenosis: a prospective, randomized study comparing decompressive laminectomy and arthrodesis with and without spinal instrumentation. Spine (Phila Pa 1976) 1997; 22:2807-12. [PMID: 9431616 DOI: 10.1097/00007632-199712150-00003] [Citation(s) in RCA: 585] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
STUDY DESIGN This prospective study analyzed the influence of transpedicular instrumented on the operative treatment of patients with degenerative spondylolisthesis and spinal stenosis. OBJECTIVES To determine whether the addition of transpedicular instrumented improves the clinical outcome and fusion rate of patients undergoing posterolateral fusion after decompression for spinal stenosis with concomitant degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA Decompression is often necessary in the treatment of symptomatic patients who have degenerative spondylolisthesis and spinal stenosis. Results of recent studies demonstrated that outcomes are significantly improved if posterolateral arthrodesis is performed at the listhesed level. A meta-analysis of the literature concluded that adjunctive spinal instrumentation for this procedure can enhance the fusion rate, although the effect on clinical outcome remains uncertain. METHODS Seventy-six patients who had symptomatic spinal stenosis associated with degenerative lumbar spondylolisthesis were prospectively studied. All patients underwent posterior decompression with concomitant posterolateral intertransverse process arthrodesis. The patients were randomized to a segmental transpedicular instrumented or noninstrumented group. RESULTS Sixty-seven patients were available for a 2-year follow-up. Clinical outcome was excellent or good in 76% of the patients in whom instrumentation was placed and in 85% of those in whom no instrumentation was placed (P = 0.45). Successful arthrodesis occurred in 82% of the instrumented cases versus 45% of the noninstrumented cases (P = 0.0015). Overall, successful fusion did not influence patient outcome (P = 0.435). CONCLUSIONS In patients undergoing single-level posterolateral fusion for degenerative spondylolisthesis with spinal stenosis, the use of pedicle screws may lead to a higher fusion rate, but clinical outcome shows no improvement in pain in the back and lower limbs.
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Affiliation(s)
- J S Fischgrund
- William Beaumont Hospital, Department of Orthopaedic Surgery, Royal Oak, Michigan, USA
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Stedman CM, Montgomery DM, Richardson AF. Advantages of a second-generation obstetrical outcome report that stratifies by payer category and accounts for maternal transfers. Am J Obstet Gynecol 1997. [DOI: 10.1016/s0002-9378(97)80484-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Payne DH, Fischgrund JS, Herkowitz HN, Barry RL, Kurz LT, Montgomery DM. Efficacy of closed wound suction drainage after single-level lumbar laminectomy. J Spinal Disord 1996; 9:401-3. [PMID: 8938608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The use of closed suction drainage after spinal surgery remains controversial. The purpose of this study was to determine the indications for closed suction drainage after single-level lumbar surgery. Two hundred patients who were scheduled to undergo single-level lumbar surgery without fusion were prospectively randomized into two groups. One group had a closed wound suction drain placed deep to the lumbodorsal fascia before routine closure, whereas the second group had no drain placed. Hemostasis was achieved in all patients before the surgeon had knowledge of the randomization outcome. All drains were removed on the 2nd postoperative day, and the amount of drainage was recorded. After surgery, the patients were evaluated for signs and symptoms of continued wound drainage, hematoma/seroma formation, and/or infection as well as evidence of an acquired neurologic deficit. One hundred three patients had a drain placed before closure and two patients developed postoperative wound infection, both of which were successfully treated with orally administered antibiotics. Of the 97 patients who had no drain placed after the surgical procedure, one patient developed a postoperative wound infection that was treated with surgical incision and drainage, as well as intravenously administered antibiotics. Statistical analysis revealed that the presence or absence of a drain did not affect the postoperative infection rate. No new neurologic deficits occurred in any postoperative patient. The use of drains in single-level lumbar laminectomy without fusion did not affect patient outcome. There was no significant difference in the rate of infection or wound healing and no patient developed a postoperative neurologic deficit.
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Affiliation(s)
- D H Payne
- Department of Orthopaedic Surgery, William Beaumont Hospital, Royal Oak, MI 48073, USA
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Bradnam MS, Montgomery DM, Evans AL, Keating D, McClure EA, Damato BE, McFadzean R. Objective detection of hemifield and quadrantic field defects by visual evoked cortical potentials. Br J Ophthalmol 1996; 80:297-303. [PMID: 8703877 PMCID: PMC505452 DOI: 10.1136/bjo.80.4.297] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
AIMS/BACKGROUND An objective method for detecting hemifield and quadrantic visual field defects has been developed using steady state visual evoked cortical potentials (VECPs), an adaptive noise canceller (ANC), and Hotelling's t2 statistic. The purpose of this study was to determine the sensitivity and specificity of the technique. METHODS Nine subjects (mean age 44 years) were investigated with field loss due to a variety of causes including both anterior and posterior visual pathway lesions. Dynamic perimetry was performed by means of a Goldmann or Tübingen perimeter. VECP recordings were made from each visual field quadrant (23 degrees X 23 degrees) by means of a steady state reversing checkerboard (7.7 rev/s). The central 5 degrees of the visual field and the vertical and horizontal meridians were masked during these measurements. Recordings were made from three electrode sites, positioned over the visual cortex, relative to a mid frontal electrode. Each recording lasted 2 minutes, during which time fixation was monitored. The data from each recording were divided into 4 second segments, and the amplitude and phase of the VECP signal measured using the ANC. Hotelling's t2 statistic was applied to determine the probability of signal detection. Receiver operating characteristic curves were used to find the optimum signal detection threshold for identification of the visual field defects. RESULTS The results of the study confirmed patterns of subjective visual field loss. The technique had a sensitivity and a specificity of 81% and 85%, respectively, for detecting 'non-seeing' areas in the inferior visual field, and 82% and 89%, respectively, for detecting 'non-seeing' areas in the superior visual field. CONCLUSION These results demonstrate that the technique is of potential clinical value to ophthalmologists and neurologists when subjective perimetry is not possible.
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Affiliation(s)
- M S Bradnam
- Department of Clinical Physics and Bio-Engineering, Yorkhill NHS Trust, Glasgow
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Jonas JB, Montgomery DM. Determination of the neuroretinal rim area using the horizontal and vertical disc and cup diameters. Graefes Arch Clin Exp Ophthalmol 1995; 233:690-3. [PMID: 8566824 DOI: 10.1007/bf00164670] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND This study evaluated whether the neuroretinal rim area can be calculated on the basis of the horizontal and vertical diameters of the optic disc and cup applying the formula of an ellipse. METHODS Color stereo optic disc photographs of 587 normal subjects and 1193 patients with glaucoma were morphometrically examined. In a first method, the areas of the optic disc and cup were planimetrically measured and the area of the neuroretinal rim was determined as optic disc area minus cup area. In a second method, the optic disc and cup were assumed to have an elliptical shape. Their areas were calculated by applying the formula of an ellipse, taking into account their horizontal and vertical diameters. As in the first method, the rim area was then determined as disc area minus cup area. RESULTS The values of the neuroretinal rim area as measured using the first method differed by 0.05 +/- 0.05 mm2 from the values as calculated by the second method. The average error was 2.8 +/- 2.9% for the normal group and 8.2 +/- 20.8% for the glaucoma patients. It increased with decreasing neuroretinal rim area and increasing mean visual field defect. CONCLUSIONS For clinical purposes, the neuroretinal rim area can be determined on the basis of the horizontal and vertical diameters of the optic disc and cup. The horizontal and vertical disc and cup diameters being determinable upon ophthalmoscopy, this finding is important for the direct measurement of optic disc morphology during any ophthalmoscopic examination.
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Affiliation(s)
- J B Jonas
- Department of Ophthalmology, University Eye Hospital, Erlangen, Germany
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Montgomery DM, Dean AC, Wiffen P, Macaskie LE. Phosphatase production and activity in Citrobacter freundii and a naturally occurring, heavy-metal-accumulating Citrobacter sp. Microbiology (Reading) 1995; 141 ( Pt 10):2433-41. [PMID: 7582003 DOI: 10.1099/13500872-141-10-2433] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The ability of a naturally occurring Citrobacter sp. to accumulate cadmium has been attributed to cellular precipitation of CdHPO4, utilizing HPO4(2-) liberated via the activity of an overproduced, Cd-resistant acid-type phosphatase. Phosphatase production and heavy metal accumulation by batch cultures of this strain (N14) and a phosphatase-deficient mutant were compared with two reference strains of Citrobacter freundii. Only strain N14 expressed a high level of acid phosphatase and accumulated lanthanum and uranyl ion enzymically. Acid phosphatase is regulated via carbon-starvation; although the C. freundii strains overexpressed phosphatase activity in carbon-limiting continuous culture, this was approximately 20-fold less than the activity of strain N14 grown similarly. Citrobacter strain N14 was originally isolated from a metal-contaminated soil environment; phosphatase overproduction and metal accumulation were postulated as a detoxification mechanism. However, application of Cd-stress, and enrichment for Cd-resistant C. freundii ('training'), reduced the phosphatase activity of this organism by about 50% as compared to Cd-unstressed cultures. The acid phosphatase of C. freundii and Citrobacter N14 had a similar pattern of resistance to some diagnostic reagents. The enzyme of the latter is similar to the PhoN acid phosphatase of Salmonella typhimurium described by other workers; the results are discussed with respect to the known phosphatases of the enterobacteria.
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Montgomery DM, Egan IF, Pollard HP. Palpable unilateral sacral prominence as a clinical sign of lower limb anisomelia: a pilot study. J Manipulative Physiol Ther 1995; 18:353-6. [PMID: 7595109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To examine the role of oblique-axis sacral torsion in the presence of true or apparent short leg. DESIGN Prospective blind trial of eighteen subjects. SETTING A suburban chiropractic practice, a hospital and a university campus. SUBJECTS Of 33 subjects selected, 27 completed the study, 8 exhibited elimination criteria, and 1 X-ray was nondiagnostic. MAIN RESULTS 3 x 3 contingency table showed the presence of unilateral sacral prominence as statistically significant (p > .001) in subjects with LLI. The incidence of unilateral sacral prominence on the short leg side was also significant (p > .05). Weighted kappa confirmed both (alpha > .001). CONCLUSIONS Oblique-axis sacral torsion may play a role in intrapelvic adaptation to anisomelia of the lower limb; further examination of this prospect is warranted.
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Affiliation(s)
- D M Montgomery
- School of Medical Radiation Technology, Faculty of Health Sciences, University of Sydney, Australia
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Bradnam MS, Montgomery DM, Moseley H, Dutton GN. Quantitative assessment of the blue-light hazard during indirect ophthalmoscopy and the increase in the "safe" operating period achieved using a yellow lens. Ophthalmology 1995; 102:799-804. [PMID: 7777279 DOI: 10.1016/s0161-6420(95)30954-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
PURPOSE The indirect ophthalmoscope presents a blue-light hazard with the potential for causing photochemical injury to the retina. In this study, this hazard was assessed with respect to the threshold limit values (TLVs) recently adopted by the American Conference of Governmental Industrial Hygienists. METHOD Spectral radiometric measurements were made from a standard indirect ophthalmoscope headset used in conjunction with either a clear or a yellow lens. The results were weighted spectrally with the published blue-light hazard function. RESULTS When the clear lens was used, the TLV was exceeded after approximately 2.5 minutes. The yellow lens filtered out the more hazardous blue wavelengths of light and this increased the "safe" operating period by a factor of approximately 20. CONCLUSION In clinical practice, with a clear lens, the TLV could be exceeded easily if the patient is subjected to prolonged or repeated examination because the blue-light hazard is additive in a linear manner for periods as long as 3 hours with a potential for a cumulative effect over longer periods. Furthermore, some ophthalmic patients, such as those with aphakia, are less tolerant of blue-light than healthy subjects. In the interests of patient safety, it is recommended that yellow lenses are considered for use for routine indirect ophthalmoscopy.
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Affiliation(s)
- M S Bradnam
- West of Scotland Health Boards' Department of Clinical Physics and Bio-Engineering, Glasgow
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12
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Abstract
Translational motion of low-grade spondylolisthesis is traditionally assessed with lateral flexion and extension radiographs. Maximum motion in an unanesthetized patient may be limited by patient cooperation, pain, or muscle spasm. Twenty-four patients with degenerative or isthmic spondylolisthesis were assessed with preoperative lateral flexion and extension radiographs. A lateral radiograph was obtained on the operating room table after administering an anesthetic, exposing the spine, and performing a laminectomy. The percentage slip decreased from 24 to 15 to 6% on flexion, extension, and intraoperative lateral radiographs, respectively (p < 0.001). The amount of reduction did not correlate with disc height, slip angle, slip level, or type of spondylolisthesis. Many low-grade spondylolisthesis deformities reduce almost completely on the operating table. Translational motion of spondylolisthesis is greater than preoperative flexion and extension radiographs indicate.
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Affiliation(s)
- D M Montgomery
- Department of Orthopaedic Surgery, William Beaumont Hospital, Royal Oak, Michigan
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Bradnam MS, Evans AL, Montgomery DM, Keating D, Damato BE, Cluckie A, Allan D. A personal computer-based visual evoked potential stimulus and recording system. Doc Ophthalmol 1994; 86:81-93. [PMID: 7956688 DOI: 10.1007/bf01224630] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A system for recording electroretinograms and visual evoked cortical potentials has been constructed with the use of a personal computer and a digital signal processing card. The system is based on widely available commercial hardware. It has been designed to be capable of performing routine visual electrophysiology as well as allowing the development of novel visual stimuli and signal detection techniques. The system enables both transient and steady-state stimulation rates. Pattern stimuli can be presented in pattern-reversal, pattern-onset, pattern-offset or motion-onset modes. In addition to conventional signal averaging, the digital signal processing card can also provide on-line Fourier analysis and is facilitating the development of adaptive filtering techniques for the detection of steady-state visual evoked cortical potentials. This versatile system is in regular clinical use for the measurement of electroretinograms and visual evoked cortical potentials.
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Affiliation(s)
- M S Bradnam
- West of Scotland Health Boards, Department of Clinical Physics and Bio-Engineering, Glasgow, UK
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Abstract
A photographic questionnaire has been used to investigate whether or not clinicians have realistic expectations of their ability to distinguish optic discs associated with glaucomatous visual field loss from discs of healthy eyes. The questionnaire consisting of 30 non-stereoscopic fundus photographs from 15 patients was administered to 40 ophthalmologists of varying experience and 10 optometrists. Each group displayed large discrepancies between their expected and achieved scores suggesting that clinicians may overestimate their ability to recognize the glaucomatous optic disc. This could lead to diagnostic errors especially in cases where tonometric and visual field parameters are considered equivocal. An over-reliance on the cup/disc ratio appeared to be the most likely cause of error.
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Affiliation(s)
- D M Montgomery
- Tennent Institute of Ophthalmology, University of Glasgow, Western Infirmary, UK
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Abstract
This study investigated the inter-observer reproducibility of measurements of the optic nerve head as carried out with a clinical optic disc biometer. This instrument employs a modification of indirect ophthalmoscopy to enable measurement of fundus structures. Measurements were made independently by two observers on 84 eyes of 47 patients. The median inter-observer differences for each measurement were as follows: maximum disc diameter, 0.085 mm; minimum disc diameter, 0.080 mm; maximum cup diameter, 0.098 mm; minimum cup diameter, 0.078 mm; disc area, 0.225 mm2; neuroretinal rim area, 0.215 mm2. Utilising the above measurements, the instrument automatically calculates a 'rim index' to take account of variations in disc size. It then interprets the disc as normal, suspicious or glaucomatous. The optic disc biometer produced seriously conflicting interpretations in 8 discs, 7 of which had been judged by both observers to have indistinct boundaries of the disc or cup.
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Affiliation(s)
- A A Pyott
- Department of Ophthalmology, Southern General Hospital, Glasgow, UK
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Fischgrund JS, Montgomery DM. Diagnosis and treatment of discogenic low back pain. Orthop Rev 1993; 22:311-318. [PMID: 8474769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Low back pain (LBP) is very prevalent in the general population. Treatment of nonradicular back pain, in the absence of deformity, continues to be controversial. Recently, anatomic dissections, magnetic resonance imaging studies, and the use of provocative discograms (pain-related response during the injection similar to the typical pattern of pain reported prior to the procedure) have contributed to our understanding of the etiology of discogenic back pain. Various techniques of spine fusion, with and without instrumentation, have altered the natural history of LBP unresponsive to conservative treatment. This review discusses the etiology and diagnosis of discogenic back pain and the treatment options available to the spine surgeon.
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Affiliation(s)
- J S Fischgrund
- Department of Orthopaedic Surgery, William Beaumont Hospital, Royal Oak, Michigan
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Abstract
PURPOSE To assess the potential of a clinical method of optic disc measurement in the detection of early neuroretinal rim loss in glaucoma. METHODS A method of disc biometry based on indirect ophthalmoscopy was used to estimate disc and neuroretinal rim areas in 81 ocular hypertensive eyes of 43 patients and in 28 fellow eyes with normal visual fields of patients with unilateral visual field loss from primary open-angle glaucoma. The results were compared with those from age-matched visually normal patients. RESULTS Neuroretinal rim area was significantly smaller in both hypertensive and fellow eye groups compared with controls (P < 0.0001; P = 0.0009). Disc area also was smaller in both groups (P = 0.0034; P = 0.046); however, this was inadequate to explain the differences in rim area, which, when corrected for disc size, were still highly significant (P < 0.0001; P = 0.0001). CONCLUSION The differences in neuroretinal rim area observed are likely to indicate that a proportion of the eyes studied had suffered a reduction of neuroretinal rim area, which was measurable by this method at a stage before the development of demonstrable visual field loss.
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Affiliation(s)
- D M Montgomery
- Tennent Institute of Ophthalmology, Western Infirmary, Glasgow, Scotland
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Montgomery DM, Brower RS. Cervical spondylotic myelopathy. Clinical syndrome and natural history. Orthop Clin North Am 1992; 23:487-93. [PMID: 1620540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A wide-based spastic gait is the classical presentation of the patient with cervical spondylotic myelopathy. A complete neurologic evaluation is needed to determine the degree of involvement and to classify the clinical syndrome. The natural history seems to be one of static neurologic deficit or episodic progression.
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Affiliation(s)
- D M Montgomery
- Department of Orthopaedic Surgery, William Beaumont Hospital, Royal Oak, Michigan
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Abstract
A simple device is described which both facilitates and significantly extends the scope of indirect ophthalmoscopy.
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Affiliation(s)
- D M Montgomery
- Tennent Institute of Ophthalmology, University of Glasgow
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Montgomery DM, Stedman CM, Robichaux AG, Joyner JC, Scariano SM. Cord blood gas patterns identifying newborns at increased risk of group B streptococcal sepsis. Obstet Gynecol 1991; 78:774-7. [PMID: 1923195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effect of group B streptococcal sepsis acquired in utero on umbilical cord gas values is not known. Hypothesizing that fetal acid-base balance may be affected, we sought to identify a pattern of cord gas values that might detect newborns at increased risk of group B streptococcal sepsis. This review encompassed all newborns from January 1, 1986 to March 31, 1990 who manifested group B streptococcal sepsis as confirmed by a positive blood culture. An increased-risk cord gas profile was identified as an arterial pH less than 7.18 with either an arterial carbon dioxide pressure less than 59 mmHg or bicarbonate level less than 19 mEq/L. This pattern was found in four of 11 newborns with group B streptococcal disease but in only 43 of 4290 controls, yielding a relative risk of 51.7 (95% confidence interval 13.1-224.9). Our results suggest that a mild metabolic acidosis characterized by these indices may serve as an indicator of increased risk of early-onset group B streptococcal disease.
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Affiliation(s)
- D M Montgomery
- Department of Obstetrics and Gynecology, Ochsner Clinic, New Orleans, Louisiana
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Asrat T, Lewis DF, Garite TJ, Major CA, Nageotte MP, Towers CV, Montgomery DM, Dorchester WA. Rate of recurrence of preterm premature rupture of membranes in consecutive pregnancies. Am J Obstet Gynecol 1991; 165:1111-5. [PMID: 1951524 DOI: 10.1016/0002-9378(91)90481-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The reported incidence of preterm premature rupture of membranes ranges between 1% and 2% of all pregnancies. The rate of recurrence is poorly defined. The goal of this study was to establish the frequency of recurrence in a high-risk referral practice. Over a 5-year period we identified 121 patients with preterm premature rupture of membranes who had a minimum of two consecutive pregnancies under our care, resulting in a total of 255 pregnancies for analysis. Recurrent preterm premature rupture of membranes occurred in 39 of 121 patients, for a rate of 32.2% (95% confidence interval, 23.9 +/- 40.5). We were unable to demonstrate an association between the estimated gestational age at the time of rupture in the index pregnancy, latency period, interval between pregnancies, and the probability of repeat preterm premature rupture of membranes in the next pregnancy. We conclude that patients with preterm premature rupture of membranes should be counseled regarding the significant risk of recurrence and need to have close follow-up in their subsequent pregnancies.
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Affiliation(s)
- T Asrat
- Department of Obstetrics and Gynecology, University of California, Irvine
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Abstract
A technique based on indirect ophthalmoscopy has been devised to enable measurement of structures in the posterior pole of the eye. It has been used to measure clinically the maximal and minimal diameters of both the optic disc and cup of 130 normal eyes from 66 patients and 33 optic discs from 20 patients with glaucomatous visual field loss. The disc area and neuroretinal rim area were derived mathematically for each eye. In the normal group the neuroretinal rim area was strongly correlated with the disc area (r = 0.89, P less than 0.0001). Only 9.1% of the glaucomatous group fell within the 95% prediction interval for the normal group, indicating a high degree of sensitivity and specificity for predicting the presence of visual field loss. Discs associated with mild field loss could be discriminated from those associated with moderate or severe field loss on the basis of disc and rim area measurements.
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Affiliation(s)
- D M Montgomery
- Tennent Institute of Ophthalmology, University of Glasgow, Scotland
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Montgomery DM, Aronson DD, Lee CL, LaMont RL. Posterior spinal fusion: allograft versus autograft bone. J Spinal Disord 1990; 3:370-5. [PMID: 2134450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effectiveness of allograft bone for posterior spinal fusion in neuromuscular scoliosis is controversial. Thirty patients with cerebral palsy, treated with posterior spinal fusion, were divided into two groups. Group 1 consisted of 18 patients treated by posterior spinal fusion using autogenous bone graft. Group 2 consisted of 12 patients treated by posterior spinal fusion using freeze-dried allograft bone. The average preoperative curve of 70 degrees in Group 1 was corrected to 35 degrees (50% correction). At 3.2 years average follow-up, the curves averaged 51 degrees (46% loss of correction). The average preoperative curve of 80 degrees in Group 2 was corrected to 39 degrees (51% correction). At 3.5 years average follow-up, the curves averaged 54 degrees (38% loss of correction). Anesthesia time decreased from 344 to 281 minutes (p less than 0.05), and intraoperative blood loss decreased from 2730 to 1740 ml (p less than 0.025) when allograft bone was used as a substitute for autograft bone. Freeze-dried allograft bone is a readily available, safe, and effective substitute for autogenous bone graft in patients with cerebral palsy undergoing posterior spinal fusion.
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Affiliation(s)
- D M Montgomery
- Department of Orthopaedic Surgery, Wayne State University School of Medicine, Children's Hospital of Michigan, Detroit
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Abstract
The effect of pupil dilatation with tropicamide 1% on visual acuity and accommodation was assessed in 100 eyes of 52 consecutive patients attending the general ophthalmic outpatient clinic. Snellen visual acuity remained unchanged in 55 eyes and deteriorated by one line in 41 eyes. The remaining four eyes deteriorated by two lines. Tropicamide gave rise to a reduction in the amplitude of accommodation which tended to vary inversely with the age of the patient. However, all patients who wore reading glasses for presbyopia were still able to read when their pupils had been dilated.
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Affiliation(s)
- D M Montgomery
- Tennent Institute of Ophthalmology, Western Infirmary, Glasgow
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Abstract
Resolving osteochondromas were previously thought to be uncommon. Two cases are presented, including the first report of a resolving solitary osteochondroma of the proximal tibia. These cases, along with previous reports, suggest resolution may occur, especially in boys under age 12 years. Surgical excision should be delayed in this group of patients provided malignant transformation or neurovascular compromise is not a concern.
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Affiliation(s)
- D M Montgomery
- Department of Orthopedic Surgery, Wayne State University School of Medicine, Detroit 48201
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Sangeorzan BJ, Montgomery DM, Manoli A. Unusual penetrating injury of the knee joint. A case report. Clin Orthop Relat Res 1988:153-5. [PMID: 3342559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Although not commonly recognized, glass may be radiopaque in soft tissue. Its density can be similar to that of bone, and it may be misinterpreted as fracture fragments. The radiodensity of glass is dependent on its varying quantities of iron, silicon, dioxide, aluminum, calcium, magnesium, and sodium salts. The awareness that the radiodensity of glass can be similar to that of human bone on roentgenogram can help the surgeon avoid the pitfall of misdiagnosis. Roentgenograms may be used to detect intraarticular glass and to assist in a localization of glass imbedded in the soft tissue.
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Affiliation(s)
- B J Sangeorzan
- Department of Orthopaedic Surgery, Wayne State University School of Medicine, Detroit, Michigan
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Sodd VJ, Fortman DL, Montgomery DM. Follow-up investigation of the 89Sr, 90Sr and 238Pu, 239Pu and 240Pu content in fission-produced 99Mo-99mTc generators. Health Phys 1980; 38:71. [PMID: 6821537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Affiliation(s)
- V J Sodd
- Nuclear Medicine Laboratory, FDA, BRH, Cincinnati General Hospital, OH 45267
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