The Cervical and Lumbar Vertebrae — An Anthropometric Model

An anthropometric model for human vertebrae in the mid-sagital plane is described, using parameters which were measured from lateral X-rays of the cervical and lumbar regions in normal, healthy men. The data was processed statistically and results are presented. The findings reported are new in the literature. They can be used in many ways, including modelling of the spine, and orthopaedics. Clinically significant parameters are the heights of the vertebral bodies and the intervertebral spacings. The relations between these parameters are presented and discussed.

Atrial natriuretic peptide levels after different types of inferior wall myocardial infarction

BACKGROUND

Atrial natriuretic peptide (ANP) is released from cardiac atrium secondary to increased atrial pressure. The plasma levels of ANP have been found to be related to short- and long-term prognosis after acute myocardial infarction (MI). The purpose of the present study was to investigate the plasma levels of ANP in three groups of patients with inferior wall acute MI classified according to ST-segment depression in the precordial leads.

METHODS

The study population consisted of 18 patients with inferior wall acute MI classified into three types: Type 1 = no precordial ST-segment depression (7 patients), Type 2 = sum of ST-segment depression in leads V1 to V3 equal to or more than the sum of ST-segment depression in leads V4 to V6 (4 patients), and Type 3 = maximal precordial ST-segment depression in leads V4 to V6 (7 patients).

RESULTS

Radioimmunoassay showed that plasma ANP levels were significantly higher in patients with Type 3 acute inferior wall myocardial infarction compared with those with Types 1 and 2 (313.1 +/- 233, 73.0 +/- 27.5), and 84 +/- 32.7 pg/ml, respectively, p = 0.018).

CONCLUSIONS

Plasma ANP levels are higher in patients with Type 3 acute inferior wall MI compared with patients with Types 1 and 2. These findings, together with earlier ones, may contribute to our understanding of the pathophysiology of the presence of ST-segment depression in the precordial leads in inferior wall acute MI.

Persistent ST segment depression in precordial leads V5-V6 after Q-wave anterior wall myocardial infarction is associated with restrictive physiology of the left ventricle

OBJECTIVES

To examine the relationship between the persistence of ST segment depression in leads V5-V6 after Q-wave anterior wall myocardial infarction (MI) and the filling pattern of the left ventricle (LV).

BACKGROUND

Precordial ST segment depression predominantly in leads V5-V6 is associated with increased in-hospital morbidity and mortality after acute myocardial ischemia, perhaps due to reduced diastolic distensibility of the LV.

METHODS

We prospectively studied 19 patients after Q-wave anterior wall MI (>6 months). All patients underwent 12-lead ECG recording, symptom-limited treadmill exercise testing with single photon emission computed tomography thallium-201 imaging, transthoracic Doppler echocardiography, cardiac catheterization and measurement of circulating atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels. Patients were classified based on the presence of ST segment depression in leads V5-V6: Group I = ST segment depression <0.1 mV (n = 10); Group II = ST segment depression > or =0.1 mV (n = 9).

RESULTS

Patients in Group II had greater LV end diastolic pressures (32.4 +/- 6.5 mm Hg vs. 14.8 +/- 6.1 mm Hg; p = 0.0001), higher plasma ANP (44.4 +/- 47.1 pg/ml vs. 10.7 +/- 14 pg/ml; p = 0.04) and BNP levels (89.4 +/- 62.7 pg/ml vs. 23.6 +/- 33.1 pg/ml; p = 0.01), greater left atrium area (20.6 +/- 3.1 cm2 vs. 17.8 +/- 2.4 cm2; p = 0.05), lower peak atrial (A), higher early (E) mitral inflow velocities, a higher E/A ratio and a lower deceleration time (167 +/- 44 ms vs. 220 +/- 40 ms; p = 0.05). Lung thallium uptake during exercise was more common in Group II (78% vs. 10%, p = 0.04).

CONCLUSIONS

Persistent ST segment depression in leads V5-V6 in survivors of Q-wave anterior wall MI is associated with increased LV filling pressure and a restrictive LV filling pattern.

Upper-limb Postures and Movements during Diamond Polishing

Previous occupational health studies of diamond polishers have identified high rates of musculoskeletal disorders of the hands and arms in this population, specifically, ulnar neuropathy in the right elbow. These disorders may be due to the repetitive and forceful motions of the upper extremity required to manipulate the hand-held polishing tools. A video-based, biomechanical analysis of the upper extremities of polishers at several diamond-processing factories in Israel was conducted. Detailed motion measurements of the wrists, elbows, and shoulders of polishers were made while the subjects performed their usual work. During a typical workday, the basic polishing cycle, which involves a series of stereotyped hand and arm movements, is repeated more than 5,000 times. Sustained, extreme flexion of the right elbow, which is the arm holding the eyepiece, may account for the higher rates of ulnar neuropathy in this extremity.

Growth hormone (GH) stimulates insulin-like growth factor-I (IGF-I) and IGF-binding protein (IGFBP)-2 gene expression in spleens of juvenile rats

Growth and development of the spleen involves the growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis. To evaluate the molecular mechanism of these effects we studied the effect of hypophysectomy (Hx) and GH replacement therapy on the expression of IGF-I, the IGF-I receptor and IGF-binding protein-2 (IGFBP-2) in juvenile rats. Hx resulted in a 30% reduction in body weight. GH replacement therapy for seven days partially prevented these effects. IGF-I mRNA levels were reduced 30% by Hx, IGFBP-2 mRNA levels fell 50% whereas IGF-I receptor mRNA levels were unaffected. GH therapy prevented the reduction in IGF-I and IGFBP-2 mRNA levels. These results suggest that the GH effect on splenic growth and development is via local (paracrine) IGF-I expression, in addition to any effect by circulating (endocrine) IGF-I.

Growth hormone (GH) stimulates insulin-like growth factor-I (IGF-I) and IGF-I-binding protein-3, but not GH receptor gene expression in livers of juvenile rats

In the adult rat, expression of the liver GH receptor, insulin-like growth factor-I (IGF-I), and IGF-I-binding protein-3 (IGFBP-3) genes has been shown to be under GH control. Additionally, hypophysectomy and GH treatment have a differential effect on the relative abundance of liver IGF-I mRNA variants in adult rats. To further elucidate the time of appearance and the extent of GH control of liver GH receptor, IGF-I, and IGFBP-3 gene expression, we studied the effect of hypophysectomy and GH and IGF-I treatment in juvenile rats. Male Wistar rats were hypophysectomized (Hx) on postnatal day 26 and received twice daily sc injections of saline, recombinant human GH (2.5 U/kg.day), or recombinant human IGF-I (500 micrograms/kg.day) for 7 days. Sham-operated rats received the same treatment. Hx animals also received T4 (20 micrograms/kg.day). In Hx animals, there was a significant reduction in body weight (69.8 +/- 6.6 vs. 100.4 +/- 5.4 g; P < 0.001). GH, but not IGF-I, treatment increased body weight (79.6 +/- 9.6 g after GH vs. 69.8 +/- 6.6 g before GH; P < 0.05). GH treatment partially maintained liver, kidney, and lung weights in Hx animals and increased them in intact animals, whereas IGF-I treatment did so only in the lungs of intact and Hx animals. Serum GH and IGF-I levels were markedly reduced in Hx animals compared with those in intact controls, and GH treatment maintained, albeit partially, circulating IGF-I levels compared with those in saline-treated Hx animals. IGF-I mRNA levels were markedly reduced in Hx liver (25.0 +/- 5.4%; P < 0.001 compared with intact controls). GH treatment for 7 days increased IGF-I mRNA levels by 4.8-fold over the levels in 9-day Hx animals and increased IGF-I mRNA levels by 2.2-fold in control rats. Hypophysectomy decreased exon 2-containing transcripts by 7.0-fold and exon 1-containing transcripts by 4.1-fold. GH treatment, however, affected both exon 1- and exon 2-containing transcripts similarly. Hepatic IGFBP-3 mRNA levels were reduced in Hx (53.2 +/- 1.8%; P < 0.01 compared with intact controls) and IGF-treated Hx animals, but were not decreased in Hx GH-treated animals (100.6 +/- 9.5). No changes in GH receptor or GH-binding protein mRNA levels were caused by Hx, GH, or IGF-I treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of sodium valproate on the secretion of prolactin, cortisol and growth hormone in migraine patients

A single oral dose of 500 mg sodium valproate had no effect on prolactin, growth hormone and cortisol secretion in 10 migraine patients when compared with five healthy controls and four migraine patients receiving placebo. Basal values of prolactin (PRL), cortisol and growth hormone (GH) were within the normal range, though PRL basal levels were lower in three patients (21.5%) in the migraine group.

A technique for assessment of torso kinesiology

A technique is described for monitoring and analysis of the angular displacement of the human torso. The technique is based on the use of miniature electromechanical inclinometers and video recording. The system was developed for continuous measurement of the angular displacement of spinal segments in the sagittal plane during all stages of lifting. Angular displacements of the cervical, thoracic and lumbar regions were obtained from a dynamic lifting case study using a digital processing system. The geometrical changes of the torso during five prescribed stages were measured. The system revealed good accuracy with high correlation coefficient scores for a wide range of lifting tasks in a comparative laboratory study. This paper describes the monitoring technique; the system's advantages, disadvantages and measuring accuracy are discussed.

Beta-endorphins in acute myocardial infarction

The endogenous peptide B-endorphin (B-EP) is closely connected with different aspects of homeostasis, behavior, and in particular with the perception of pain. The purpose of this study was to investigate the correlation between: the level of plasma B-EP and the intensity of pain in acute myocardial infarction (AMI); and the B-EP and specific enzymes for AMI serum glutamic oxolo-acetic transferase, lactate dehydrogenase, and creatine phosphokinase and some stress hormones (cortisol, growth hormone). Twenty-six patients hospitalized in the CCU for acute MI were studied during the first 72 hours from the onset of symptoms. Seven normal subjects served as controls. Blood was taken for hormone and B-EP evaluation before treating the patients by opiates. Plasma B-EP levels were determined using the protocol of the Immunonuclear Corporation (Stillwater, MN). Statistical analysis of the results showed: Nonsignificant differences between B-EP levels of all MI patients and control group. Unaltered B-EP levels in patients with acute MI suffering from moderate pain. Significant differences in drop of B-EP in the group with most severe pain (p less than 0.025). A tendency toward decreased B-EP in patients suffering from more prolonged pain (greater than 6 hours). Significant negative correlation was shown between B-EP and chest pain intensity (0-4 graduation) (r = 0.8, p less than 0.01); lactate dehydrogenase (r = 0.7, p less than 0.01); serum glutamic oxolo-acetic transferase (r = 0.6, p less than 0.01); creatine phosphokinase (r = 0.6, p less than 0.05; plasma cortisol level (r = 0.5, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

A study of vertebra and disc geometric relations of the human cervical and lumbar spine

Geometric configuration and dimensions of the human vertebra were investigated using x-ray photographs of 157 normal, healthy men. A simplified model of the vertebra in the midsagittal plane is presented and used as a basis for measurements. Geometric considerations and statistical analysis served for correlating significant measurements of vertebral bodies and intervertebral disks of the human spine.

Dimensions of human lumbar vertebrae in the sagittal plane

Geometrical dimensions of the lumbar segments were determined from a series of lateral radiographs. A two-dimensional model of the lumbar vertebra in the sagittal plane is used. The model is based on five landmarks, which enable the determination of twelve geometrical parameters. The sample includes 157 healthy young males, 20-38 years old. Two-dimensional analysis of vertebral body height, depth and intervertebral spacing was performed. In all subjects disc height increases from L1 to L5, while anterior height is always bigger than posterior height, which emphasizes the lordotic shape of the lumbar region. Anthropometrical values are presented and geometrical relations between the lumbar segments are discussed.

Sagittal evaluation of elemental geometrical dimensions of human vertebrae

Geometrical configuration and dimensions of the human vertebra were investigated using radiographs of 157 normal healthy adult men. Measurements were based on five bony reference points, which can be defined in radiographs. The measurements permit the determination of nine dimensions that can be used for anthropometrical evaluation of the cervical and lumbar vertebrae. A simplified model of the vertebra in the sagittal plane is presented and serves as a basis for the geometrical measurements. In the cervical region, average width exceeded average height of vertebral bodies C3 to C7, while in C2 the average width was smaller than the average height; C7 was the longest and C3 the shortest cervical vertebra. In the lumbar region, average width exceeded average height of the vertebral bodies. Values for width and height did not differ significantly from L1 to L5; L3 was the longest and L5 the shortest lumbar vertebra.

Sagittal radiographic measurements of the cervical and lumbar vertebrae in normal adults

Lateral radiographs of 157 healthy adult males have been measured to obtain geometrical dimensions of cervical and lumbar vertebrae. Measurements were based on five bony landmarks which can be easily defined in radiographs. The measurements enable the determination of 11 dimensions that are used for anthropometric evaluations of the human vertebrae. We found the cervical vertebrae increasing slightly in width from C3 to C7, while the width of the lumbar vertebrae remained almost constant. The width and height of lumbar vertebrae were approximately twice those of the cervical ones.

Motion pattern analysis for evaluation and design of a prosthetic hook

This study was designed to evaluate motion patterns of individuals with upper extremity amputations while performing a manual task. The objectives were to analyze performance time of repeatable motion elements that constituted the locomotion of upper extremity amputees, and to develop the performance profile which could be used as an evaluation method of hand prostheses. The findings identified a significant difference in performance ability for motion element grasp, as compared to motion elements reach, move, position, and release. Performance profile of amputee patients was introduced. The profile displayed the contribution of the various motion elements to the overall performance time. The performance profile was used to evaluate the standard prosthetic hook, and served as a criterion for the design of a new functional hook.

Using an elemental analysis of the motion pattern to assess the work performance of amputees

Twelve different objects were manipulated to test the usefulness of a standard industrial engineering method analysis procedure in evaluating amputees' motions. A profile was developed for analyzing the performance of amputees. The profile displays the contribution of the various motion elements to the overall task performance time. The study tested whether this procedure could identify motion elements that produce significant difficulties and time delays in amputees' occupational performance. Actual (measured) performance time of Methods Time Measurement (MTM) elements were compared for two subject groups, amputees and nonamputees. Kinesiological analysis and biomechanical considerations supported the utility of such a profile. Amputees' performance profiles can be used, for example, to improve the design of prosthetic devices that replace the natural hand.