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3.
J Am Diet Assoc ; 100(8): 911-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10955049

RESUMO

OBJECTIVES: To evaluate the feasibility of implementing 3 specific prompting methods among students in the first and fourth grades (mean age = 7.2 and 10.1 years, respectively), to validate recall accuracy of first- and fourth-grade students against observation, to develop a single measure of inaccuracy that cumulated errors in reporting food items and amounts without allowing underreporting and overreporting to cancel each other, and to establish information regarding the measure of inaccuracy for use in future studies. DESIGN: Children were interviewed the morning after they were observed eating lunch provided by the school. Interviews included free recall, nonsuggestive prompted recall, and specific prompted recall (either preference, food category, or visual). SUBJECTS/SETTING: Ninety-six children (48 students per grade) were studied--32 per the specific prompting method--stratified by grade, sex, and ethnicity (African-American or white). Specific prompting method was randomly assigned to children within strata. STATISTICAL ANALYSIS: Food items were categorized and weighted as: combination entree = 2, condiments = 1/3, and other = 1. To calculate inaccuracy of recall, absolute differences between amounts reported and observed eaten were calculated for each item and then multiplied by each item's weight; these values were then summed across all items for each child. Inaccuracy of recall was determined before specific prompting and after specific prompting and for the difference (inaccuracy after specific prompting minus inaccuracy before specific prompting). RESULTS: Before specific prompting, median inaccuracy was 2.7 servings for the 48 first-grade students and 1.7 servings for the 48 fourth-grade students. The median difference in inaccuracy from before to after specific prompting was 0 for both grades. Specific prompting increased recall accuracy for 9 first-graders and 12 fourth-graders, but decreased recall accuracy for 21 first-graders and 7 fourth-graders, and did not change recall accuracy for 18 first-graders and 29 fourth-graders. Among children whose recall accuracy increased after specific prompting, 5 first-graders and 8 fourth-graders received prompting for food category. APPLICATIONS/CONCLUSIONS: Among first-grade students, specific prompting (either preference, food category, or visual) may hurt more than help recall accuracy. Among fourth-grade students, prompting for food category yields small gains in recall accuracy with minimal losses. Validation studies are needed with larger sample sizes to determine prompting methods that produce more accurate dietary recalls from children of various socioeconomic status groups, other racial/ethnic groups, and at other meals.


Assuntos
Registros de Dieta , Serviços de Alimentação , Instituições Acadêmicas , Análise de Variância , Criança , Estudos de Viabilidade , Feminino , Humanos , Entrevistas como Assunto , Masculino , Rememoração Mental , Reprodutibilidade dos Testes , Fatores de Tempo
4.
Med Sci Sports Exerc ; 31(11): 1619-22, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10589866

RESUMO

PURPOSE: High levels of day-to-day or intraindividual variability implies unreliability of a measure of physical activity. Unreliability in a measure leads to attenuation of correlations with other variables. As intraindividual variability increases, the number of days necessary to assess physical activity to achieve the desired level of reliability increases. The use of an intraclass correlation to assess day-to-day reliability in a measure assumes compound symmetry. METHODS: This study reports on these issues in a sample of 165 elementary school teachers who maintained a 7-d record of physical activity each year for 3 yr. Analyses were conduced with physical activity measured as minutes, MET minutes, and kcal. Analyses were conducted with PROC MIXED in SAS controlling for the clustering effect by school. RESULTS: Compound symmetry could not be supported across 7 d of the record. The weekdays tended to intercorrelate, Saturday correlated at very low levels, and Sunday correlated with Monday only. Compound symmetry was supported across the three weeks. CONCLUSIONS: To achieve a reliability of 0.8 using a 7-d activity record requires 2 wk of assessment. The reliability of measures of physical activity require more careful attention, and likely require more points of assessment to achieve desired levels.


Assuntos
Exercício Físico , Prontuários Médicos , Atividades Cotidianas , Distribuição de Qui-Quadrado , Estudos de Coortes , Metabolismo Energético , Feminino , Humanos , Funções Verossimilhança , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Esportes , Fatores de Tempo
5.
Nutrition ; 15(11-12): 848-53, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10575659

RESUMO

This study investigated the impact of entree and liking for foods on the accuracy and order of reporting on children's school lunch recalls. Data were collected during a series of studies to investigate children's lunch recalls from a cognitive processing approach to understand better how children remember what they have eaten. Fourth-grade children from four schools were randomly selected, observed eating lunch, and interviewed the same (n = 89) or next (n = 148) day. Foods were classified as matches (observed and reported eaten), omissions (observed but not reported eaten), or phantoms (not observed but reported eaten), and corresponding rates were calculated. Statistical analyses included z tests and permutation tests. For same- and next-day recalls, children were more likely to report entree than other meal components earlier in the interview. For next-day recalls, the phantom rate for the remaining items was lower for children who reported entrees accurately versus inaccurately. For items liked "a lot" compared with items "not liked a lot," match rates were higher for next-day recalls, and phantom rates were lower for both same- and next-day recalls. Because entree and liking for foods appear to play salient roles in children's dietary recalls, these results provide guidance regarding the development of specific prompts to increase the accuracy of children's dietary recalls.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Registros de Dieta , Preferências Alimentares , Rememoração Mental , Criança , Humanos , Sensibilidade e Especificidade
6.
Invest Radiol ; 34(9): 558-65, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10485070

RESUMO

RATIONALE AND OBJECTIVES: To evaluate the effect of the transverse ligament on translation of the menisci. METHODS: Six cadaveric knees were examined by MR imaging inside a positioning device before and after transecting the transverse ligament. The knees were examined at various positions: extension, 30 degrees of flexion, 60 degrees of flexion, and full flexion. Sagittal T1-weighted spin-echo images were generated at each knee position and evaluated for statistical differences with regard to anterior-posterior meniscal excursion. RESULTS: Statistically significant differences in meniscal excursion were found before and after transsecting the transverse ligament for anterior-posterior meniscal motion of the anterior horn of the medial meniscus at 30 degrees of knee flexion. No such significant differences were found, however, at 60 degrees of flexion and full flexion in anterior-posterior meniscal excursion of the anterior or posterior horn of either meniscus before and after transsecting the transverse ligament. CONCLUSIONS: The transverse ligament has a restricting effect on anterior-posterior excursion of the anterior horn of the medial meniscus at lower degrees of knee flexion.


Assuntos
Articulação do Joelho/anatomia & histologia , Ligamentos Articulares/anatomia & histologia , Imagem Cinética por Ressonância Magnética , Meniscos Tibiais/fisiologia , Amplitude de Movimento Articular , Idoso , Idoso de 80 Anos ou mais , Artroscopia , Fenômenos Biomecânicos , Cadáver , Feminino , Humanos , Articulação do Joelho/fisiologia , Ligamentos Articulares/fisiologia , Masculino , Meniscos Tibiais/anatomia & histologia
7.
Assessment ; 6(3): 225-34, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10445960

RESUMO

Internal consistency, temporal stability, and principal components structures of two self-report anger expression scales used in pediatric health research were examined in 415 youth (216 White, 199 Black; 191 boys, 224 girls; mean age 14.7 years). Participants completed the Anger Expression Scale (AXS) and the Pediatric Anger Expression Scale (PAES) on two occasions separated by approximately 1 year. Psychometric properties of the two scales were examined and compared with those reported by the scale authors. For both the AXS and the PAES, estimates of internal consistency (Cronbach s alpha) were acceptable and comparable to values reported by scale authors. Temporal stability of both scales was significant over 1 year. Principal components structures for both scales were similar to those reported by scale authors. Results were generally consistent for age groupings (<13, 13 years), ethnicity, and gender. It is concluded that further research using the AXS and PAES is warranted. The stability of anger expression over time and the assessment of anger suppression is discussed.


Assuntos
Ira , Emoções Manifestas , Testes Psicológicos , Psicometria/métodos , Adolescente , Adulto , Negro ou Afro-Americano/psicologia , Fatores Etários , Criança , Análise Fatorial , Feminino , Humanos , Masculino , Fatores Sexuais , População Branca/psicologia
9.
Ann Plast Surg ; 40(3): 235-40, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9523605

RESUMO

A retrospective study of 350 reduction mammaplasties by the inferior pedicle technique performed over a 3-year period allows a critical evaluation of postoperative complications and patient satisfaction. The procedure can be done in a timely manner on an outpatient basis and is applicable to breasts of different shapes and sizes. The rate of postoperative complications (5%) was comparable with previous studies. Patient satisfaction was high (98%), with near-total relief of preoperative symptoms. Concern about the resultant scars was low (2%) when the incisions followed the natural contour of the breast.


Assuntos
Mamoplastia/métodos , Adulto , Feminino , Humanos , Satisfação do Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Retalhos Cirúrgicos
10.
J Am Acad Dermatol ; 38(1): 27-31, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9448201

RESUMO

BACKGROUND: Numerous telemedicine programs have been created in the United States, but studies documenting the fidelity and effectiveness of telemedicine for evaluation of skin diseases are lacking. OBJECTIVE: We attempted to determine the percentage of encounters in which two different dermatologists, one using telemedicine and one on-site, could independently arrive at the same primary diagnosis. METHODS: Two clinical telemedicine sites linked through the Georgia Statewide Telemedicine Program were used in this study of 60 patients with skin problems. One dermatologist evaluated the patients on telemedicine (interactive television) and a second then took the patients into a separate examination room and evaluated them on-site. Each investigator recorded their diagnoses with no discussion with each other. As a control group, the investigators independently and in a blinded fashion (to each other's diagnoses) recorded diagnoses for a group of patients from a third dermatologist's clinic. Raw data were evaluated and classified by this third dermatologist who assigned diagnoses to categories of complete agreement, partial agreement, or disagreement. RESULTS: There were no significant differences with regard to disagreement. However, there was a higher probability of complete agreement between the two dermatologists when each examined the patient on-site and in person than when one evaluated the patient on telemedicine and one examined the patient on-site and in person. CONCLUSION: Our results suggest that telemedicine is an effective means of diagnosing cutaneous diseases. However, because partial interobserver agreement on diagnoses was greater for the telemedicine group than for the control group (p < 0.05), it is likely that optimum use of medical assistants at the remote site will be necessary to increase the likelihood of complete agreement on diagnoses among dermatologists using interactive television.


Assuntos
Consulta Remota , Dermatopatias/diagnóstico , Dermatologia , Georgia , Humanos , Variações Dependentes do Observador , Exame Físico , Assistentes Médicos , Projetos Piloto , Probabilidade , Método Simples-Cego , Televisão
11.
J Am Diet Assoc ; 97(11): 1293-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9366868

RESUMO

OBJECTIVE: To validate fourth-graders' self-reports of school lunch by comparing their reports to lunch observations, and to determine the impact on accuracy of gender, ethnicity, meal component, and time interval between eating and reporting. DESIGN: Students were randomly selected, observed eating lunch, and interviewed the same day, next day, or Monday regarding Friday's lunch. Accuracy of reporting items was determined by tallying matched foods (items reported and observed), phantom foods (items reported but not observed), and omitted foods (items not reported but observed). Accuracy of reporting amount eaten was determined by calculating absolute and arithmetic differences. SUBJECTS: Subjects were 260 students: 89 same-day, 148 next-day, and 23 Monday recalls; 59 whites (30 boys) and 201 blacks (103 boys) from four schools. STATISTICAL ANALYSES: Rates for matched, phantom, and omitted foods; analysis of variance; Friedman's nonparametric analog of analysis of variance; Student-Newman-Keuls' post hoc comparisons. RESULTS: In regard to reporting items, the respective rates for matched, phantom, and omitted foods were 84%, 5%, and 16% for same-day recalls; 68%, 13%, and 32% for next-day recalls; and 38%, 48%, and 62% for Monday recalls. Rates for omitted and phantom foods were higher for Monday recalls than for next-day recalls, which were higher than for same-day recalls (P < .05 for all). In regard to reporting amounts, analysis by gender, ethnicity, and time interval failed to yield significant main or interaction effects. When children correctly reported items eaten, they were quite accurate in reporting amounts eaten. Omitted food rates were lowest for beverage, followed by entree, and highest for miscellaneous and condiment. APPLICATIONS: Even under the best conditions (ie, reporting within 90 minutes after eating school lunch), children have difficulty accurately reporting what they have eaten. As the time interval between eating and reporting increases, accuracy decreases markedly. Techniques that improve reporting of items eaten should result in improved accuracy of reporting amounts eaten.


Assuntos
Alimentos , Rememoração Mental , Análise de Variância , Criança , Etnicidade , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Fatores Sexuais , Fatores de Tempo
12.
Am Surg ; 63(3): 205-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9036884

RESUMO

Various studies of the effect of hyperbaric oxygen (HBO) in a wide variety of disease entities have been carried out. In the treatment of burns, animal and human studies have yielded somewhat contradictory results. Controlled studies in humans are limited. A randomized study on the effect of HBO was conducted involving 125 burn patients admitted within 24 hours of injury who were matched by age, burn size, and presence or absence of inhalation injury. Patients in the treatment arm received oxygen at two atmospheres of pressure for 90 minutes twice a day for a minimum of 10 treatments and a maximum of one treatment per total body surface per cent burn. The control group was treated in a similar fashion, except for the absence of HBO. There were no statistically significant differences between the two groups for the outcome measures of mortality, number of operations, and length of stay for the survivors. In this large clinical trial, we were unable to demonstrate any significant benefit to burn patients from the use of HBO.


Assuntos
Queimaduras/terapia , Oxigenoterapia Hiperbárica , Adulto , Queimaduras/mortalidade , Queimaduras/cirurgia , Distribuição de Qui-Quadrado , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Análise de Sobrevida , Resultado do Tratamento
13.
J Am Diet Assoc ; 97(1): 31-6, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8990414

RESUMO

OBJECTIVE: To develop and validate a consensus set of retrieval categories for how children remember what they have eaten, and to relate retrieval categories to accuracy of reporting items eaten during school lunch. DESIGN: A Delphi technique study was conducted using 10 psychologists. The subject matter consisted of responses transcribed from interviews conducted with 89 randomly selected fourth graders within 90 minutes of eating. Retrieval categories were evaluated for accuracy by comparing students' self-reported lunch intake with observation. STATISTICAL ANALYSES: For round 1, a centroid hierarchical cluster analysis was used to identify common sets of rating pairs to propose categories for reaching consensus. For rounds 2 and 3, percent of agreement was calculated. Accuracy was tabulated across meal items and student use by retrieval category. RESULTS: After round 3, we found that 23 "near-consensus" categories were used by at least eight raters. Six categories were used 60% of the time, 4 were used 20% of the time, and 5 were used 15% of the time. Less frequently used categories were combined with similar, more frequently used categories for a total of 16 categories. Students used a large variety of retrieval categories when accurately reporting consumption. Of the 16 categories, 12 were used similarly by both accurate and inaccurate students. Where there were differences in accuracy by retrieval category, the more accurate students used "taste/smell/texture" and "visual" in deference to "order items consumed" and "oral cue still present." APPLICATIONS: These categories provide insight into the broad range of retrieval categories that children use and provide direction for researchers to design and study specific cues to enhance the accuracy of children's self-reports of diet.


Assuntos
Técnica Delphi , Ingestão de Alimentos , Rememoração Mental , Criança , Humanos , Entrevistas como Assunto , Reprodutibilidade dos Testes
14.
Am J Sports Med ; 24(3): 286-92, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8734877

RESUMO

We conducted this cadaveric study to define a biomechanical rationale for rotator cuff function in several deficiency states. A dynamic shoulder testing apparatus was used to examine change in middle deltoid muscle force and humeral translation associated with simulated rotator cuff tendon paralyses and various sizes of rotator cuff tears. Supraspinatus paralysis resulted in a significant increase (101%) in the middle deltoid force required to initiate abduction. This increase diminished to only 12% for full glenohumeral abduction. The glenohumeral joint maintained ball-and-socket kinematics during glenohumeral abduction in the scapular plane with an intact rotator cuff. No significant alterations in humeral translation occurred with a simulated supraspinatus paralysis, nor with 1-, 3-, and 5-cm rotator cuff tears, provided the infraspinatus tendon was functional. Global tears resulted in an inability to elevate beyond 25 degrees of glenohumeral abduction despite a threefold increase in middle deltoid force. These results validated the importance of the supraspinatus tendon during the initiation of abduction. Glenohumeral joint motion was not affected when the "transverse force couple" (subscapularis, infraspinatus, and teres minor tendons) remained intact. Significant changes in glenohumeral joint motion occurred only if paralysis or anatomic deficiency violated this force couple. Finally, this model confirmed that rotator cuff disease treatment must address function in addition to anatomy.


Assuntos
Manguito Rotador/fisiopatologia , Articulação do Ombro/fisiopatologia , Idoso , Fenômenos Biomecânicos , Cadáver , Humanos , Úmero/fisiopatologia , Pessoa de Meia-Idade , Movimento , Contração Muscular , Músculo Esquelético/fisiopatologia , Paralisia/fisiopatologia , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Rotação , Lesões do Manguito Rotador , Ruptura , Escápula/fisiopatologia , Lesões do Ombro , Tendões/fisiopatologia
15.
J Am Coll Nutr ; 15(1): 56-64, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8632116

RESUMO

OBJECTIVE: We developed, pilot-tested, and field-applied a stages of change questionnaire regarding fruit and vegetable (F&V) consumption among fourth- and fifth-grade students. METHODS: The design included cross-sectional assessment of internal consistency and construct validity, and 2-week and 7-week longitudinal assessment of test-retest reliability. Subjects included 134 students from one school for pilot-testing and 252 from two schools for field application. Thirty-two questions from McConnaughy et al's stages of change questionnaire were adapted and pilot-tested; minor revisions were made for field application. Statistical analyses included principal components analysis to identify subscales; cluster analysis to identify subgroups within students; Cronbach's alpha coefficient to assess internal consistencies; Pearson product-moment correlations to assess test-retest reliabilities; and oneway ANOVA's by F&V stages of change clusters with actual F&V consumption, F&V self-efficacy subscales, F&V preferences, and F&V outcome expectations subscales to determine construct validity. RESULTS: Principal components analysis from the field application indicated two subscales (precontemplation and beyond precontemplation) accounting for 39.5% of variance. Cluster analysis indicated 6 interpretable clusters; 2 (n = 63) provided responses inconsistent with the stages of change theory and 4 (n = 189) provided responses consistent with the theory. Internal consistencies and test-retest reliabilities were acceptable. Students in the "beyond precontemplation" clusters had higher levels of self-efficacy and outcome expectations regarding eating F&V. CONCLUSIONS: Measuring stages of change other than the precontemplation stage in F&V consumption among elementary school children is problematic. Perhaps the theoretical concept does not apply to children, or elementary school children lack the ability to comprehend the questions measuring the concept, or the approach used was not entirely appropriate.


Assuntos
Alimentos , Frutas , Verduras , Atitude Frente a Saúde , Criança , Análise por Conglomerados , Promoção da Saúde , Humanos , Projetos Piloto , Reprodutibilidade dos Testes , Inquéritos e Questionários
16.
J Clin Periodontol ; 22(12): 953-7, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8613565

RESUMO

This study was conducted to determine whether the gingival tissue lateral to the periodontal sulcus contributes resistance to the advancement of a periodontal probe tip into the sulcus under different applied pressures. An electromechanical device was used to advance a probe tip 0.6 mm in diameter into the facial sulcus at a constant speed until resisting forces of 0.70 N were encountered. The device registered the resisting force and probe advancement simultaneously. The gingiva of all 2nd incisors, 2nd premolars, and 1st molars of 4 young adult male beagle dogs were tested. After the first measurement, the buccal gingiva of experimental sites were incised mesiodistally from the gingival margin to the alveolar crest and the sulcus was reprobed. 2 experimental and control quadrants were selected randomly resulting in 6 sets of both experimental and control data from each animal. The data were analyzed with analysis of variance. The analysis demonstrated significant variation from site to site, and dog to dog; therefore, only changes between the 1st and 2nd probings at the same sites could be compared. Less variability of probing distance in different animals occurred at higher forces; however, the incision had a significant effect on probing distance at these forces. The pressure at which probing distance had less variability among animals and least affected when the gingival sulcular wall was incised was estimated to be 106 N/cm2. This corresponds to 30 g force on the 0.6 mm diameter probe.


Assuntos
Gengiva/fisiologia , Periodontia/instrumentação , Análise de Variância , Animais , Dente Pré-Molar , Cães , Desenho de Equipamento , Gengiva/anatomia & histologia , Gengiva/cirurgia , Incisivo , Masculino , Dente Molar , Periodonto/anatomia & histologia , Periodonto/fisiologia , Pressão , Estresse Mecânico
17.
Neurology ; 45(8): 1494-9, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7644047

RESUMO

The relative effects of antiepileptic drugs (AEDs) on cognition are controversial. We compared the cognitive effects of phenobarbital, phenytoin, and valproate in 59 healthy adults using a randomized, double-blind, incomplete-block, crossover design. Cognitive assessments were conducted at baseline, after 1 month on each drug (two AEDs per subject), and at two repeat baselines 11 weeks after each AED treatment. The neuropsychological battery included 12 tests, yielding 22 variables: Choice Reaction Time, P3 Event-Related Potential, Finger Tapping, Lafayette Grooved Pegboard, Selective Reminding Test, Paragraph Memory, Complex Figures, Symbol Digit Modalities Test, Stroop Test, Visual Serial Addition Test, Hopkins Symptom Checklist, and Profile of Mood States. More than one-half of the variables exhibited AED effects when compared with nondrug baselines, and all three AEDs produced some untoward effects. Differential AED effects on cognition were present for approximately one-third of the variables. Phenobarbital produced the worst performance; there was no clinically significant difference between phenytoin and valproate.


Assuntos
Cognição , Fenobarbital/farmacologia , Fenitoína/farmacologia , Ácido Valproico/farmacologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Valores de Referência
18.
J Biomech ; 28(7): 869-74, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7657685

RESUMO

A dynamic shoulder testing apparatus has been developed to examine unconstrained glenohumeral joint motion in human cadaveric full upper extremities. Six computer-controlled hydraulic cylinders are used to simulate muscle action, while the corresponding tendon excursions and six-degree of freedom joint motion are measured. Trials showed that the testing apparatus creates highly reproducible glenohumeral joint motion in the scapular plane. The apparatus can be used to examine the function of the shoulder musculature and capsuloligamentous structures during normal and pathologic motion at the glenohumeral joint.


Assuntos
Articulação do Ombro/fisiologia , Computadores , Ergometria/instrumentação , Humanos , Úmero/fisiologia , Artropatias/fisiopatologia , Ligamentos Articulares/fisiologia , Movimento , Contração Muscular , Músculo Esquelético/fisiologia , Rotação , Escápula/fisiologia , Tendões/fisiologia
19.
J Shoulder Elbow Surg ; 4(3): 199-208, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7552678

RESUMO

Muscle force values and tendon excursions across the glenohumeral joint during unconstrained glenohumeral abduction in the scapular plane were evaluated with a dynamic shoulder testing apparatus. This evaluation was achieved by simulated rotator cuff and middle deltoid activity applied in four plausible muscle force ratios: (1) equal force to each tendon, (2) 2:3 ratio of force applied to the middle deltoid/supraspinatus tendons, (3) 3:2 ratio of force applied to the middle deltoid/supraspinatus tendons, and (4) zero force applied to the supraspinatus tendon to simulate supraspinatus paralysis. The glenohumeral joint was then moved to 5 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, and maximum glenohumeral abduction while muscle forces, tendon excursions, and glenohumeral joint kinematics were monitored. Full glenohumeral abduction was achieved in all four test conditions. When the muscle force combination favored the middle deltoid, the smallest supraspinatus force was required from 30 degrees to maximum glenohumeral abduction; however, when the supraspinatus was favored, the largest supraspinatus force was necessary to achieve maximum glenohumeral abduction. With simulated supraspinatus paralysis the middle deltoid required the greatest increase in force from 15 degrees through 45 degrees of glenohumeral abduction. These results indicate that muscle efficiency during glenohumeral abduction is highly dependent on the ratio of applied force between the middle deltoid and supraspinatus. A larger contribution of force from the supraspinatus was required near the beginning of motion, whereas the middle deltoid was more important near the end of glenohumeral abduction in the scapular plane. Tendon excursion for the middle deltoid (6.4 +/- 0.2 cm) and supraspinatus (3.8 +/- 0.2 cm) were proportionately larger than those for the subscapularis and infraspinatus. Humeral head translations on the glenoid were less than 2 mm in all four conditions evaluated; therefore the glenohumeral joint behaves kinematically as a "ball-and-socket" articulation during glenohumeral abduction. Simulated supraspinatus paralysis does not change normal joint kinematics and does not prevent full glenohumeral abduction.


Assuntos
Manguito Rotador/fisiologia , Articulação do Ombro/fisiologia , Ombro/fisiologia , Idoso , Cadáver , Humanos , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Amplitude de Movimento Articular/fisiologia
20.
J Periodontol ; 66(3): 184-90, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7776162

RESUMO

The purpose of this study was to locate the position of the periodontal probe tip using a pressure of 126 N/cm2 (force of 0.30N using a round periodontal probe tip with a diameter of 0.55 mm). The influence of gingival inflammation on this position was also studied. Subjects with three levels of periodontal health and disease were entered into the study and each contributed one experimental tooth. At each site a standardized probing system was used to place a probe into a clinical pocket. The probe tip was luted to the test tooth surface. The tooth with its gingival tissue and probe tip was extracted, fixed, and processed for histological measurements. Distances in mm were obtained from the cemento-enamel junction (CEJ) to the probe tip, to the base of the crevice/pocket, and to the most coronal connective tissue attachment. Analysis of the data indicated that clinical inflammation was not a factor in the placement of the probe tip at crevice/pocket's landmarks relative to the CEJ; however variability of probing may have caused the non-significance. The probing system placed the probe tip 0.66 mm apical to the base of the crevice/pocket and 0.06 mm coronal to the most coronal connective tissue attachment. These conclusions corroborated the results of the previous study in dogs which predicted probe placement of 0.44 mm apical to the base of the crevice using the standardized pressure of this probing system.


Assuntos
Instrumentos Odontológicos/normas , Doenças Periodontais/diagnóstico , Periodontia/instrumentação , Análise de Variância , Diagnóstico Bucal/instrumentação , Feminino , Gengivite/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Bolsa Periodontal/diagnóstico , Pressão
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