The term for the science of size, proportion, weight, and height is ______________.

Direct anthropometry

Farkas was the first to apply medical anthropometry to children with repaired bilateral cleft lip.61 His reference book is invaluable.62 It contains normative values for 28 nasal and 18 labial linear/angular measurements in a North American Caucasian population from birth (0–5 months and 6–12 months) and each year up to age 18. Direct anthropometry requires training, practice, and patience. The tools are a sliding Vernier caliper and a Castroviejo caliper. Locating the soft-tissue landmarks and measuring nasolabial dimensions are usually easily accomplished in a child older than 5 years, but difficult to impossible in a younger child. Intraoperative anthropometry is used to assess severity of the deformity prior to the procedure and immediately after repair as a record of baseline nasolabial dimensions.6 In an analysis of 46 consecutive repairs of bilateral complete cleft lip, intraoperative anthropometry confirmed the strategy of design in three dimensions in anticipation of the fourth dimension. All fast-growing nasolabial features were set smaller than age and sex-matched normal infants. The only exception was central vermilion–mucosal height (median tubercle) that purposely was made overly full (on average 155% of normal). The slow-growing features, nasal protrusion, and columellar height, were also constructed longer than normal, 130% and 167%, respectively.

Direct anthropometry can be repeated as the child grows and compared to normal values based on sex and age. This was shown in a retrospective longitudinal analysis of 12 children with bilateral complete cleft lip who underwent repair with the same procedure as described herein.4 Through age 4 years, nasal height and protrusion, as well as columellar length and width, were within 1 standard deviation of normal values. The interalar dimension was overly wide, about 1 standard deviation above normal. Nevertheless, the nose often did not appear wide because children with bilateral cleft lip tend to have minor orbital hypertelorbitism. The cutaneous lip was intentionally set short because this is less eye-catching than the typical long lip appearance in these patients. Thus, total lip height was 1–2 standard deviations below normal, whereas, height of the median tubercle was 1 standard deviation above normal at 4 years. Fullness of the central red lip usually falls below normal in older children. Depending on the show of the permanent incisors, the median tubercle either is augmented or excess mucosa is trimmed. An example of an 8-year-old boy with repaired bilateral complete cleft lip/palate is shown inFig. 22.19 with intraoperative and postoperative anthropometry.

Serial direct anthropometry in 32/48 patients with repaired bilateral incomplete cleft lip was compared to Farkas's normative values.63 Females, African-Americans, and Asians were excluded because of their small numbers, leaving 22 Caucasian males in the long-term study. Nasal measurements demonstrated: interalar dimension (al–al) widened in early childhood and followed line of normal growth thereafter; nasal tip protrusion (sn–prn) grew in parallel above the normal line; columellar height (sn–c) crossed the normal line in early childhood and remained slightly below into adulthood. Labial measurements showed: Cupid's bow width (cphi–cphi) was normal into late adolescence; upper philtral width (cphs–cphs) remained below the normal line; philtral height (sn–ls) stayed below the normal line; median tubercle (ls–sto) grew slowly, sometimes dropping below the normal line during adolescence; total labial height (sn–sto) closely approximated Farkas's normal line throughout childhood and adolescence.

Discussion

Anthropometry and anthroposcopy have been the most important research tools in biological and forensic anthropology. These two methods of observation and data collection can be made both on the living and on skeletonized human remains. As research tools, they have contributed to the analysis of human variation in terms of race, sex and body dimensions, such as stature. These areas of research have explained those dimensions and morphological features that describe sexual dimorphism, and the differences between sexes that may have been caused by social and physical environmental factors or simply by evolutionary mechanisms, such as selection. Many growth studies of the musculoskeletal system have been based on anthropometry of children. Predictions can be made from such studies; for example, to determine whether a child has the chromosomal mutation that will cause the Down syndrome, or what the predicted height will be at a given age.

Forensic anthropological anthropometric (and osteometric) dimensions have been used to develop many discriminant function formulae to determine sex and race from the skeleton. They are also used to estimate stature from long bones. These and other uses assist the police in identifying both the unknown victim and the culprit who may have committed the crime. The same dimensions in the study of a video recording of a crime scene, facial size and proportions of facial features can be estimated: for example, the length of a person's nose can be estimated from a video image and a photograph. Some anthropologists even attempt to estimate stature and the proportions of one part of the body to another in video surveillance images recorded during the commission of a crime.

Morphological analysis of unmeasurable features usually falls into the area of anthroposcopy. These features are assessed qualitatively (without using any measuring device) by an experienced person. While some anthropologists use models to compare morphological features, experience is extremely important because of the geographic diversity of the human species and resulting differences between them. Its use in forensic anthropology is mainly seen in the analysis of the skeletal remains rather than living individuals. An exception to this may be the evaluation of facial images in a photograph and video tapes. To these one may add the study of growth-related changes in the human body, especially when there is the question of age estimation from the picture of a person who was thought to be a child. Morphological assessment of osteological remains are important areas of observation in forensic osteology. It provides not only features of sex and race but also shows variation in the human skeleton that may be explained in terms of asymmetry, pathology or anomaly. Each of these features may provide information about age, pathology and trauma, time since death, effects of animals on the skeleton, and information as to whether a particular feature was caused ante mortem, perimortem or post mortem.

Anthropometry

Anthropometric techniques are those in which a quantitative measure of the size, weight, or volume of a body part is used to assess protein and calorie status. Historically, one of the most commonly used anthropometric parameters has been weight for height. This is a useful parameter when neither the patient nor family can provide reliable historical information, but it is less desirable than a history of unintentional weight loss, because it requires the patient’s weight to be judged against a normative standard that has been established in a large control population, and inter-individual variability in the population limits this method’s accuracy for correctly predicting PEM in one individual.Table 5.6 displays the 1959 Metropolitan Life Insurance Company “desirable body weights” that were established with prospective mortality data. The 1959 table remains preferable to the 1983 tables largely because of concerns that the latter did not include an adequate sampling of certain segments of the population, and was therefore biased. In the context of the Metropolitan table, desirable weight for height is defined as that figure associated with maximal longevity. In general, individuals whose weight is less than 85% of the standard can be considered to have a clinically significant degree of PEM. Of note is that desirable weights in this table are substantially less than average weights in North America.

Body mass index (Table 5.18), defined as weight (in kilograms) divided by height (in meters squared), has been supplanting the use of weight for height, in part because it precludes the need to use normative data tables. BMIs outside the desirable range (18.5 to 24.9 kg/m2) help identify patients at increased risk of adverse clinical outcomes. A BMI modestly above the desirable range has been shown to be predictive of adverse outcomes in the surgical management of many diseases76-78 and in the medical management of conditions like alcoholic liver disease.79 Similarly, a low BMI has been shown to be a robust independent risk factor in surgical and medical patients.80 Extremely underweight adult patients (BMI <14 kg/m2) are at high risk of death and should be strongly considered for admission to the hospital to initiate intensive nutritional support.

The BMI, like weight for height, is a surrogate and imperfect measure of body composition. A low BMI (<18.5 kg/m2) is interpreted as an indication of PEM, and a high BMI (>24.9 kg/m2) is interpreted as excessive fat mass (overweight or obesity). Although BMI is accurate in this regard for the vast majority of adults, it can be just as misleading as other measures that rely on body weight without a direct evaluation of body composition.81 For example, the individual with excessive fluid accumulation, where actual fat and body cell mass (BCM) are less than that implied by the BMI, and the muscle-bound athlete, where a high BMI is indicative of an extraordinarily large lean mass, are two examples of how the underlying assumptions inherent in the BMI are false. Sex and race are also confounding variables, although the differences are clinically irrelevant. More important are the remarkable changes in body composition that accompany development, making the interpretation of BMI in childhood and adolescence very complex.82

Introduction

What is the reason, we might ask, for the human preoccupation with measurement of the human body? We are weighed and measured not just from the cradle to the grave, but now from only a few weeks after conception. While these preoccupations can bring benefits to health, they can also trip over into concerns that have a detrimental effect on well-being (e.g., in body image distortion in eating disorders).

Anthropometry is the technical name for this preoccupation. It is the measurement of the body’s physical features, and these measures can play a key role as variables in epidemiology, psychology, and anthropology studies. The precise and unambiguous measurements of the body’s physical dimensions and underlying composition should allow us not only to accurately characterize our current health, but also to make predictions about outcomes as diverse as our physical attractiveness, ability to reproduce, and our long-term survival. However, as this article shall outline, most of the common techniques are less precise than we would wish and, although they have a reasonable validity at the population level, can give misleading results when looking purely at an individual.

There are a host of potential anthropometric measures that could be included in any review of this type. However, this article shall concentrate primarily on those relating to body mass and body shape as these seem to be the best predictors of health and reproductive potential, although some other common measures will be considered as well.

Body Composition and Anthropometry

Body composition profiling is designed to provide a relatively detailed analysis of an individual’s muscle, fat, and bone mass.178,182 Anthropometry may be used to determine the individual’s body type (mesomorphic, endomorphic, ectomorphic) to see whether he or she is properly suited for the desired activity, exercise, sport, or position played in a sport.

Anthropometry also involves body fat measurements, such as skinfold measurements or underwater weighing.183 Of the two, skinfold measurement is more common because it is easier and faster. Seven skinfold sites are most commonly used (Fig. 17.5), although some people believe that measurement at three sites is sufficient (i.e., a different three for males and females).183 Most males should fall below 12% to 15% body fat. Endurance athletes (e.g., distance runners, gymnasts, wrestlers) are often below 7%. Football, baseball, and soccer players average 10% to 12%.184 No one should be below 5% body fat. If the percentage of body fat is greater than the upper normal limit of 14% for males and 17% for females, the patient should be put on a weight-loss program or on weight training to increase lean body mass; but again, this depends on the activity in which the patient wishes to participate.

Other methods of body composition measurement include girth measurements, bone diameter measurements, ultrasound measurement, and radiographic measurements of the arm.182

Anthropometry

Anthropometry includes measurements of body weight (estimated dry weight for dialysis patients), height, triceps skinfold, abdominal circumference, calf circumference, midarm muscle circumference, elbow breadth, and subscapular skinfold. These values provide information about the distribution of body fat and skeletal muscle mass, and over time, identify nutritional deficiencies or excesses in calorie and protein reserves compared with standardized percentiles. One of the problems with using anthropometric measurements to assess the nutrition status in CKD is that reference values are derived from healthy individuals. This is a potential pitfall given the known alterations in body composition associated with uremia and the presence of edema. Anthropometry is usually performed on the nondominant arm, but in hemodialysis patients the dominant arm is used if the contralateral arm has a vascular access in place. To minimize the interference of edema, measurements should be made during the last hour of dialysis. For routine care, anthropometric measurements are recommended every 3 to 6 months.

Neck circumference, reflecting upper body subcutaneous fat, is another anthropometric measurement that is receiving increasing attention because of its association with cardiovascular risk. The utility of this measurement in CKD populations is currently being evaluated. Other methods of assessing body composition include dual-energy x-ray absorptiometry (DEXA) and bioelectrical impedance. These techniques are accurate, but at present their use is limited to research purposes because of equipment availability, radiation dose, patient acceptance, and cost.

SOLUTE DISTRIBUTION VOLUME

To ensure that patients of varying sizes receive the same dose of dialysis, clearances are adjusted for body size. This adjustment is analogous to the practice of adjusting creatinine clearance to body surface area. For mathematical convenience, dialysis clearance is typically normalized to total body water, which is equal to the volume of distribution of urea (V), an intrinsic element in the term Kt/V. Various methods can be used to calculate V, including indicator dilution,41 bioimpedance,127 anthropometric methods,128–130 and formal urea kinetic modeling.41 The most common methods used in clinical practice are anthropometry and formal urea kinetic modeling.

Anthropometry

Anthropometric techniques are readily portable and inexpensive. The equipment required includes a tape measure, height stick, scales, and skinfold callipers. Various formulae have been developed which allow the rapid calculation of different aspects of body composition, including percentage fat derived from triceps skinfold (Table 2), and the following anthropometric equations:

Table 1. Summary of body composition measurement techniques

HPLC, high-performance liquid chromatography.

Table 2. Percentage fat derived from triceps skinfold

Adapted from Durnin JVGA and Wormersley J (1974) Body fat assessed from body density and its estimation from skin fold thickness: Measurements on 481 men and women aged from 16 to 72 years. British Journal of Nutrition 32: 77–97.

Body mass index (BMI) or Quetelet's index can be readily calculated from height and weight data: BMI = (weight in kilograms)/(height in meters)2

arm muscle circumference = mid upper-arm circumference − (n × triceps skinfold)

abdominal circumference-to-gluteal circumference ratio

abdominal circumference

In populations, an increased BMI has a good correlation with body fatness, as measured by other techniques, and correlates well with morbidity and mortality in the obese individual. In underweight populations, a reduced BMI correlated well with loss of FFM. In individuals, the BMI should be treated as an index of nutrition with more caution, since other factors determining it, such as fitness or the presence of edema, are of nutritional importance.

Trunk circumferences define fat distribution. An abdominal circumference to-gluteal circumference ratio greater than 0.95 (males) and greater than 0.85 (females) is consistent with abdominal obesity, as is an abdominal circumference greater than 103 cm in males and 93 cm in females. The abdominal circumference is measured at the midpoint between the costal margin and the iliac crest in the midaxillary line. The gluteal circumference is measured at the maximal gluteal circumference.

Skinfold thicknesses have been used to measure body fat. This method assumes that subcutaneous fat measurements represent total body fat. Various sites can be assessed and equations applied to derive body density and hence subcutaneous fat mass. Durnin and Womersley developed the regression equation using four skinfolds (biceps, triceps, subscapular, and suprailliac), gender, and age. Equations have been developed using multiple or single skinfold sites.

Precision of skinfold measurement depends on the skill of the operator as well as the character of the subcutaneous fat. In general, the error is 5%, although this can be higher in the very obese individual.

Measurement of the midarm muscle circumference has been used to estimate total body protein stores. The triceps skinfold thickness by itself has been used as a measure of total body subcutaneous fat (Table 3).

Table 3. Error of the methods

Sources: unpublished data from the Body Composition Laboratory, Monash Medical Centre, Melbourne, Australia; Lohman (1981); Lukaski et al. (1985); Mazess et al. (1989); Mazess et al. (1990): see Further Reading for details.

The arm muscle circumference (or arm muscle and bone circumference) can be derived from the arm circumference and the triceps skinfold, and it gives a good indication of protein stores. This correlation holds true particularly in underdeveloped countries, where populations tend to have little subcutaneous fat, and it can be a useful tool in diagnosis and monitoring of progress in the management of protein-energy malnutrition.

In the nonambulant elderly, knee height can be used to predict stature.

2.1 Anthropometry

Anthropometric data is used for the study of human body measurement for anthropological classification and comparison. It includes body measurements, such as height, weight and hand size, and functional measurements, principally concerning how far people can reach in different directions.

The distribution of these measurements in a population tends to follow a typical ‘bell-shaped’ curve, as illustrated in Figure 6.2. It has been common practice to design for the middle 90% of this variation. However, this approach can exclude the smallest 5% and the largest 5%, who are likely to find the product hard or impossible to use. In practice, the numbers excluded are likely to be even higher, as those who are excluded by height may not be the same as those excluded by arm length, etc.

It is also important to take into account the variation in data distribution by gender, age and geographical location. For example, a product which includes 90% of UK men may include only a small proportion of UK women, a small proportion of men over 75 or fewer than 90% of men from another country.

Anthropometric data is relatively easy to find, with basic data available for many countries. However, consistency across different data sets, and often within the same data set, is less easy to find. Data for seemingly related measurements is often gathered using different population samples, making more detailed comparative analysis difficult.

More recently, some efforts have been made to recognize the variation of measurement by age. For example, the UK Department of Trade and Industry (DTI) has published separate data for children (Norris and Wilson, 1995), adults (Peebles and Norris, 1998) and older adults (Smith et al., 2000). This provides a useful introduction to the anthropometric variation that may be associated with an aging population.

Anthropometric Measurements

Anthropometric tests have the benefit of objectivity, rapidity, and ease of interpretation. A variety of anthropometric measurements have been tested with respect to degree and risk of malnutrition, such as mid arm circumference and triceps skin-fold thickness (Durnin & Womersley, 1974). Although these modes of assessment are cheap and easy to perform, they are rarely, if ever, used for NA in patients undergoing HPB operations. Others have used surrogates of muscle wasting, such as hand-grip strength, to assess protein-energy malnutrition (Alvares-da-Silva et al, 2005). These assessments have largely been demonstrated to be incompletely characteristic of nutritional state, although they can be used in conjunction with other scoring systems to provide a clinical picture of nutrition.