CLS;AC;LASnC

Surg Radiol Anat (2009) 31:665–674
DOI 10.1007/s00276-009-0500-4
O R I G I N A L A R T I CL E
A normal data-base of posteroanterior radiographic
measurements of the wrist in healthy Egyptians
Mona Hassan Mohammed Ali
Received: 14 October 2008 / Accepted: 16 March 2009 / Published online: 8 April 2009
© Springer-Verlag 2009
Abstract The roentgenographic morphology of the wrist
has been described in textbooks and in articles but no ethnographic diVerences were reported. This study aims to
identify normal radiographic anthropometry reference values and variations according to age and sex of carpal bones
and joints in healthy Egyptians that might be useful in clinical practice. Selected landmarks were digitized on 300
posteroanterior wrist radiographs of asymptomatic volunteers. Men and women were equally represented as were
two age groups (20–40 years and above 40–60 years). The
roentgenograms were made, with standard exposure with
the wrist and forearm in the neutral positions. It was found
that in all age groups, males showed higher values than
females in most of the measurements. The width of the distal radio-ulnar joint space, ulnar variance and length of the
3rd metacarpal were reduced in older subjects while radius
of radio-carpal joint arc, carpal height, carpal–ulnar ratio
and radial inclination were increased in older subjects. In
ulnar variance and radial inclination, there were diVerences
with respect to those reported in Mexicans and in Japanese.
Information regarding normal values in wrist measurements could be used as the normal reference value for the
evaluation of surgical management and follow-up of the
wrist abnormalities.
Keywords Wrist · Carpal bones · Radiography ·
Anthropometry · Anatomy · Egyptians
M. H. Mohammed Ali (&)
Department of Anatomy and Embryology,
Faculty of Medicine, Suez Canal University, Ismailia, Egypt
e-mail: [email protected]
Introduction
Anthropometry in physical anthropology refers to the measurement of living human individuals for the purposes of
understanding human physical variation. It involves measurements that are important for studies of human growth,
population variation and clinical treatment [1]. Biological
anthropometry is always seeking accurate methods and
techniques in order to determine accurately the measurements [2]. Morphological diVerences have been shown to
exist within gender and racial groups as well as among
monozygotic twins. Therefore, every population should
have its speciWc measurements to achieve accurate sex and
age determination [3]. Morphological variation in the wrist
structures are increasingly seen as factors that may lead to
problems with the wrist [4]. Many diseases of the wrist can
be recognized by radiographic changes and quantiWed by
radiographic measurements [5]. Despite the availability of
new imaging technologies, plain radiographs are the most
frequently used for evaluating wrist bony structures [6]. To
deWne normal wrist architecture and quantify abnormalities,
distances and angles measured from bone landmarks on lateral and posteroanterior radiographs have been developed
as carpal indices. Because carpal indices were developed
and validated using posteroanterior and lateral Wlms, it is
commonly accepted that they can be reliably measured
from these views [7].
Clinicians use carpal indices among other measurements
in diagnosing and treating wrist disorders. For example,
palmar tilt, radial inclination, and ulnar variance describe
the shape of the distal radius and are used to diagnose distal
radius fractures and assess adequacy of fracture reduction
[8]. Abnormal carpal indices may lead to a decision to treat
a fracture surgically or even to reconstruct a malunited fracture. Other carpal indices such as carpal height and ulnar
123
666
translocation provide information about general collapse and
malalignment of the carpal bones and are useful both clinically and as research tools with regard to wrist arthritis [9].
The purpose of the present study is to provide an antecedent on normality with respect to the measurements of
the carpus among Egyptians, that it serves like an anthropometric catalog for the diVerent problems that aZict this
region, contributing to be useful in clinical practice and to
diminish the possibility of subcorrection or anatomofunctional subcorrection.
Subjects and methods
This is a prospective and cross-sectional study. Measurements were performed on the posteroanterior roentgenograms of the dominant wrists of 300 normal Egyptians
subjects, 150 left wrists and 150 right wrists, with Egyptians parents and grandparents who were born in Egypt.
They had been recruited on a volunteer basis and a written
consent was taken from them. In our study, we depended on
the approval and the written consent provided by the participants after explanation of the aim and the procedures of the
work. They were evenly divided into two groups according
to sex and age (middle age group from 20 to 40 years and
old age group >40–60 years) and the study subjects were
carefully selected to represent equally both sexes and both
age groups. Individuals who had a history of previous operative intervention, fractures, diabetes mellitus, rheumatoid
arthritis, congenital and/or traumatic diseases in the upper
extremities were excluded from the study.
X-ray technique and assessment
The X-rays were obtained in the Department of Radiology
of Suez Canal University Hospital in Ismailia, Egypt. Each
subject was radiologically photographed separately and
was wearing gonadal shielding. The shoulder was abducted
at 90°, the elbow Xexed at 90° and the forearm placed on
the X-ray table. One view for every subject was taken, the
posteroanterior view (PA).
In this study, true PA radiograph was deWned as one in
which there was least overlap between the radius and ulna
and the carpometacarpal joints at the base of the third metacarpal were most symmetrically open [10]. The phalanges
and metacarpal of the middle Wnger of the upper limb were
positioned coaxial to the radius and ulna (neutral position)
and the Wngers were spread slightly and completely
extended and in good contact with the Wlm. The central ray
passed through the third metacarpophalangeal joint and the
forearm was immobilized just above the wrist by means of
a sand bag [11].
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Surg Radiol Anat (2009) 31:665–674
The measurements were performed on digitizing
enlargements (mean enlargements, 2.90) of the roentgenograms that allowed precise identiWcation of the key anatomical landmarks (Figs. 1a, b, 2a, b). The enlarged
photographs of the roentgenograms were digitized with a
GRAF/PEN sonic digitizer (model GP-3) and a computer
program was designed to calculate the ratios with the use of
digitized landmarks. The measurements were corrected for
both photographic and roentgenographic magniWcations.
Normalization is a mathematical technique for the minimization of errors in measurement due to magniWcation
imposed by the divergence of the X-ray beam, as well as
for the reduction of variation when dealing with hands of
diVerent sizes.
Measurements were made in millimeters of the length
of the cord of the radio-carpal joint arc, the radius of the
radio-carpal joint arc, the space (width) and length of the
radial and ulnar sides of the distal radio-ulnar joint, the
ulnar variance, the uncovered length of the lunate, the
length of the capitate, the carpal height, the carpal–ulnar
distance, the carpal–radial distance, the length of the third
metacarpal, radial length and the lunate fossa inclination.
Apart from the alternative carpal height ratio, the other
indices, expressed as percentages (the carpal height ratio,
carpal–ulnar ratio, lunate uncovering index and carpal–
radial ratio). The alternative carpal height ratio was not
reported in percent to be able to compare our results with
other studies not given in percent. The angles measured in
degrees included those between the radius and the third
metacarpal, the radius and the capitate and the radial inclination.
Osseous Landmarks and measurements on posteroanterior
image
The osseous landmarks including the theoretical center of
rotation are not speciWc points but were selected because
they were the most reproducible points on the roentgenograms.
Distal end of the radius
The cord of the arc of the radial part of the radio-carpal
joint (BE, Fig. 1a) was the distance between the radial styloid (B, Fig. 1a) and the point of intersection between the
radial sclerotic line on the distal radio-ulnar joint and the
most distal dense line on the radio-carpal joint at the level
of the sigmoid notch (E, Fig. 1a). The axis of the distal end
of the radius (AC, Fig. 1a) was drawn by bisecting the last
6 cm of the distal end of the radius. The angle between the
radio-carpal joint line and the radial part of the distal radioulnar joint (BER, Fig. 1a) was also measured.
Surg Radiol Anat (2009) 31:665–674
667
Fig. 1 a, b Determination of the key landmarks. a Distal end of the
radius: Line AC the bisection of the last 6 cm of the radius. B The radial
styloid. E The point of intersection between the most distal sclerotic
line of the radial part of the radio-carpal joint and the sclerotic line corresponding to the radial part of the distal radio-ulnar joint (R line). BE
The cord of the arc of the radial part of the radio-carpal joint. Distal end
of the ulna: Line HI the bisection of the last 6 cm of the ulna. Third
metacarpal: line ZY the axis of the third metacarpal. Z The most proximal point of the third metacarpal along its longitudinal axis. Y The
most distal point of the third metacarpal along its longitudinal axis.
Capitate. WX the axis of the capitate. W The most proximal point of the
capitate along the principal axis. Y The most distal point of the capitate
along its main axis. T The theoretical center of rotation for radial–ulnar
deviation of the wrist, located in the head of the capitate, 1 mm ulnar
to the principal axis of the bone, at one-quarter of the total length of the
capitate, distal to its proximal end. b Distal radio-ulnar joint: E (described in a). F The point located on the sclerotic line corresponding to
the radial part of the distal radio-ulnar joint, at mid-joint and corresponding to point K located on the sclerotic line along the ulnar part of
the distal radio-ulnar joint at mid-joint. G The most proximal point of
the dense line corresponding to the radial part of the distal radio-ulnar
joint and corresponding to point J which is the most proximal point of
the ulnar part of the distal radio-ulnar joint. L The most distal point of
the ulnar part of the distal radio-ulnar joint. EG Length of the radial
part of the distal radio-ulnar joint. JL Length of the ulnar part of the distal radio-ulnar joint. CRD Carpal–radial distance. CUD Carpal–ulnar
distance. Lunate. PO Uncovered length of lunate. OQ covered length
of lunate
Distal part of the ulna
side of the distal radio-ulnar joint. The index was calculated
by dividing the length of the uncovered lunate by the projection of the entire lunate on the same line (PQ, Fig. 1b).
The axis of the distal end of the ulna (HI, Fig. 1a) was
drawn by bisecting the last 6 cm of the distal end of the
ulna.
Distal radio-ulnar joint
The width of the space at the middle of the distal radioulnar joint (FK) and the length of the radial (EG) and ulnar
(LJ) sides of the distal radio-ulnar joint were measured
(Fig. 1b).
Carpus: lunate
The uncovered portion of the lunate (PO) was measured on
a line perpendicular to the longitudinal axis of the radial
Capitate
The length of the capitate was measured along its main longitudinal axis (WX, Fig. 1a) [9].
The carpal height, carpal height ratio, carpal–ulnar
ratio, and carpal–ulnar distance were measured and calculated according to the method described by Youm [12]
and Stahelin [13]. The axis of the third metacarpal bisects
the shaft of the metacarpal and goes through the center of
the capitate while intersecting the third carpometacarpal
joint and radial articular line (Fig. 1a). This line was
extended proximally to the most distal sclerotic line of the
radius (D).
123
668
Surg Radiol Anat (2009) 31:665–674
Fig. 2 a, b Determination of the
key landmarks. a curved line M
Length of the third metacarpal.
Curved line CH Carpal height.
Angular measurements: RCA
angle between the radius and the
capitate, RMA angle between the
radius and the third metacarpal,
RI radial inclination. b A Longitudinal axis of ulna, B longitudinal axis of radius, C sclerotic
line of radius, D line perpendicular to long axis of distal ulna.
UV Ulnar variance and LFI
lunate fossa inclination
1. Carpal height (CH): is the distance between the distal
articular surface of capitate to distal articular surface of
radius (Fig. 2a) [9].
2. Carpal height ratio: carpal height/length of third metacarpal [9].
3. Alternative carpal height ratio: carpal height/length of
capitate [14].
4. The carpal–ulnar distance (CUD, Fig. 1b): is the perpendicular distance between the center of rotation of
the carpus and the longitudinal axis of the ulna projected distally [9].
5. The carpal–ulnar ratio: the carpal–ulnar distance/length
of the third metacarpal [9].
6. The carpal–radial distance (CRD, Fig. 1b): is the perpendicular distance from the center of rotation of the
carpus (T, Fig. 1a) to a line from the radial styloid that
extends distally and parallel to the axis of the distal end
of the radius. The center of rotation of the wrist was
located in the head of the capitate (T, Fig. 1a), 1 mm to
the ulnar side of the principal axis of the bone, at a
point one-fourth of the total length of the capitate, just
distal to its proximal end [9].
7. The carpal–radial ratio: carpal–radial distance/length
of the third metacarpal [9].
8. Radial length: measured by marking two lines perpendicular to the long axis of the radius, Wrst line intersects
tip of the radial styloid, second line intersects the distal
articular surface of the ulnar head and the distance
between the two lines is called the radial length [15].
9. Radial inclination (RI, Fig. 2a): describes relative angle
of distal radial articular surface to a line perpendicular
to long axis of the radius. It is measured as the angle
123
between a line from the ulnar side of the carpal side of
the carpal surface of the radius to the tip of the radial
styloid and a line perpendicular to the axis of the ulna
[16].
10. Lunate fossa inclination (LFI, Fig. 2b): is the angle
between the sclerotic line of the lunate fossa of the
radius and a line perpendicular to the long axis of the
distal ulna [15].
11. Ulnar variance (UV, Fig. 2b): after identifying the
longitudinal axis of the radius, a line is drawn through
the distal ulnar aspect of the radius that is perpendicular to its longitudinal axis. The distance between this
line and the distal cortical rim of the ulna is then
measured [15].
Statistical analysis
Each parameter was measured three times and the mean
value was used to reduce the intraobserver error (the margin of error was within 0.3° and 0.1 mm). Data was analyzed using Statistical Package for Social Science (SPSS)
version 14.0. The mean, standard deviation, Student T test
and linear and non-linear regression methods were used to
analyze the data. The level of signiWcance was P < 0.05.
Cumulative distributions were used to determine the 2.5
and 97.5 percentiles of each measurement within the general population and within men and women separately, and
these Wgures were used as the normal values. In clinical
practice, the carpal height and carpal–ulnar ratios are considered abnormal if decreased; hence, the normal values of
these indices were deWned as the Wfth and one-hundredth
percentiles. Conversely, the normal values of the carpal
Surg Radiol Anat (2009) 31:665–674
669
radial ratio, an index considered abnormal if increased,
were deWned as the 0 and 95 percentiles.
Results
Simple descriptive statistical data for the studied measurements are represented in Tables 1, 2, 3, and 4.
Table 1 represents the measurements in the middle age
group. A signiWcant diVerence between the two sexes was
found where males showed higher measurements than
females. Cord of radio-carpal joint arc, carpal height,
ulnar variance, radial length, length of capitate, carpal–
ulnar and carpal–radial distances, length of third metacarpal, radial inclination, carpal–ulnar and radial ratios and
lunate uncovered length showed the most signiWcant sexual dimorphism where P < 0.0001 for each while the carpal height ratio and lunate fossa inclination showed the
lowest signiWcance (P < 0.005). However, there was no
statistically signiWcant diVerence between both sexes in
length of radius of radio-carpal joint arc, alternative carpal height ratio, lunate uncovering ratio or in the other
angular measurements.
Table 1 Descriptive statistical
data for the measured parameters in the middle age group
Parameter
Table 2 represents the measurements in old age group.
Also, a signiWcant diVerence between males and females
was found where males presented with signiWcantly greater
mean values for most of the measurements than females.
As found in middle aged group, the old aged group showed
the highest sexual signiWcance in cord of radio-carpal joint
arc, carpal height, lengths of third metacarpal and capitate,
lunate uncovered length, radial length, radial inclination,
carpal–radial and ulnar distances while the lowest were in
carpal height ratio, lunate fossa inclination and lunate
uncovering ratio.
Changes in the anatomy of the wrist according to age are
summarized in Table 3. The width of the distal radio-ulnar
joint was 0.3 mm less in the group of older subjects; this
diVerence was found to be signiWcant (P = 0.03). Also, the
diVerences between ulnar variance, radius of radio-carpal
joint arc, the ratios of carpal height, alternative carpal
height and lunate uncovering was found to be signiWcant.
There was no relationship between age and carpal–ulnar
and radial distances or carpal height.
Table 4 summarizes changes in the anatomy of the wrist
according to sex. Most measurements that pertained to
length were shorter in women, as were the carpal–radial
Males
Females
Min.
Max.
Cord of radio-carpal joint arc (BE)
28.7
33.9
Radius of radio-carpal joint arc
28.4
50.9
Distal radio-ulnar joint space
0.9
3.5
Ulnar variance (UV)
0.40
0.43
Lunate uncovered length
4.6
12.1
Mean § SD
Min.
Max.
30.8 § 1.8
Mean § SD
Lengths (mm)
Length of capitate
20.5
26.1
Carpal height (CH)
32.9
39.9
Carpal–ulnar distance (CUD)
14.6
25.8
Carpal-radial distance (CRD)
18.1
23.7
Length of third metacarpal
61.4
73.2
Radial length
10.2
17.1
Lunate fossa inclination (LFI)
11.31
15.6
Carpal height ratio (%)
49.9
62.7
Alternative carpal height ratio
1.1
1.91
Carpal-ulnar ratio (%)
20.3
42
Lunate uncovering ratio (%)
28.79
63.8
Carpal–radial ratio (%)
26.9
35.3
Indices
Angles (°)
*P < 0.0001
**P < 0.005
Radius-third metacarpal (RMA)
0.5°
0.9°
Radius-capitate (RCA)
0.9°
1.4°
Radial inclination (RI)
24°
30°
24.4
29.4
36.7 § 7.0
26.6
53.6
1.8 § 0.68
0.9
2.7
0.42 § 1.51
0.38
0.41
6.3 § 2.6
2.3
8.7
23.2 § 1.8
17.8
23.6
35.6 § 4.4
28.4
35.9
18.7 § 3.5
11.7
19.7
20.3 § 1.4
16.1
20.2
66.1 § 4.0
56.5
68.9
9.8
14.4
10.7
13.4
53.8 § 3.06
48.3
54.2
1.53 § 0.16
1.3
1.99
29.1 § 4.7
19.8
33.6
32.4 § 10.4
28.5
63.9
31.5 § 2.1
24.8
33.5
13 § 0.081
13.61 § 4.4
0.7° § 6.1
1.1 § 10.4°
27° § 3
0.3°
0.7°
1.8°
2.7°
22°
26°
27.0 § 1.5*
36.8 § 7.34
1.5 § 0.4
0.40 § 0.95*
5.4 § 1.7*
20.7 § 1.6*
32.1 § 3.3*
15.7 § 2.4*
18.6 § 1.4*
63.1 § 3.3*
11.5 § 0.06*
12.1 § 3.2**
50.8 § 0.07**
1.55 § 0.21
26.4 § 0.5*
32.9 § 10.3
29.9 § 2.2*
0.5° § 5.6
2.1° § 11.3
24° § 4*
123
670
Table 2 Descriptive statistical
data for the measured parameters in the old age group
Surg Radiol Anat (2009) 31:665–674
Parameter
Males
Females
Min.
Max.
Mean § SD
Cord of radio-carpal
joint arc (BE)
29
34.3
Radius of radio-carpal
joint arc
30.2
Distal radio-ulnar
joint space
Mean § SD
Min.
Max.
31.2 § 2.3
25
30.4
27.4 § 2.1*
52.1
38.4 § 6.8
28.6
53.6
38.4 § 6.3
0.7
3.1
1.5 § 0.5
0.6
2.5
1.2 § 0.21
Ulnar variance (UV)
0.39
0.41
0.37
0.40
Lunate uncovered
length
4.1
11.2
0.40 § 1.6
6.8 § 2.3
2.0
8.1
0.39 § 0.89
Length of capitate
19.4
24.3
Carpal height (CH)
33.8
40.5
22.0 § 1.3
Carpal–ulnar
distance (CUD)
14.9
Carpal–radial
distance (CRD)
Lengths (mm)
5.1 § 1.43*
20.0 § 0.9*
17.7
23.1
29.0
36.4
26.1
36 § 3.4
18.9 § 3.4
11.9
19.9
18.0
23.3
20.1 § 1.8
16.0
20.0
18.4 § 1.7*
Length of third
metacarpal
61.0
72.2
65.3 § 5.09
56.0
68.4
62.5 § 3.9*
Radial length
10.2
17.1
Lunate fossa
inclination (LFI)
12.9
14.6
13 § 0.081
9.8
14.4
13.61 § 4.4
11.3
13.7
32.9 § 0.8*
16.0 § 3.2*
11.5 § 0.06*
12.1 § 3.2**
Indices
Carpal height ratio (%)
51.7
64.1
60.0
1.1
2.0
56.2 § 3.8
49.7
Alternative carpal
height ratio
1.46 § 0.16
1.0
1.9
30.3 § 3.9
20.5
33.9
33.7 § 9.8
29.7
65
34.1 § 8.4
29.3 § 2.5*
Carpal-ulnar ratio (%)
20.7
42.9
Lunate uncovering
ratio (%)
29.6
64.5
Carpal-radial ratio (%)
26.7
35.0
31.3 § 2.0
24.4
33.7
Radius-third
metacarpal (RMA)
0.5°
0.9°
0.7° § 6.4
0.49°
0.55°
Radius-capitate (RCA)
0.8°
1.7°
2.9°
25.3°
29.4°
1.0° § 7.0
1.1°
Radial inclination (RI)
22.7°
27.0°
Angles (°)
*P < 0.0001
**P < 0.005
and carpal–ulnar ratios. The alternative carpal height ratio,
length of radius of radio-carpal joint arc, lunate uncovering
ratio and the angle of radius-third metacarpal were very near
in men and women. The diVerences in the angular measurements were not signiWcant except for radial inclination.
Table 5 shows the relationships between the various anatomical parameters. The parameters assessed included
height and lengths of both third metacarpal and capitate,
ulnar variance and the lunate uncovering index; the carpal–
ulnar ratio and the carpal height ratio; the lunate uncovering
ratio and the carpal–ulnar ratio; the carpal–radial ratio and
the carpal height ratio; the carpal–radial ratio and the angle
of radial inclination; and the lengths of the capitate and the
third metacarpal. The relationships between the various
anatomical parameters were signiWcant but they had weak
coeYcients of correlation (range in R2, 0.04–0.47). In this
123
27.2° § 46
54 § 13.2**
1.44 § 0.21
26.9 § 0.43**
0.52° § 5.0
2.0° § 10.2
25° § 37*
study, the level of statistical signiWcance was set at
P < 0.05. There was a particularly close relationship
between the lengths of the capitate and the third metacarpal
and height and lengths of capitate and length of third metacarpal. There was no statistical relationship between the
ulnar variance and either the radial inclination or the carpal
height ratio but a signiWcant non-linear relationship
(P < 0.01) was found between the ulnar variance and the
lunate uncovering ratio. A quasi-linear relationship
(P < 0.001) was found between the carpal–ulnar ratio and
the carpal height ratio. There was also a signiWcant relationship (P = 0.01) between the carpal–ulnar ratio and the
lunate uncovering ratio. There was no correlation between
the carpal–radial ratio and the lunate uncovering ratio, the
ulnar variance, or the carpal–ulnar ratio. However, there
was a linear relationship between the carpal–radial ratio
Surg Radiol Anat (2009) 31:665–674
671
Table 3 Changes in the anatomy of the wrist according to age
Table 4 Changes in the anatomy of the wrist according to sex
Parameter
Parameter
Middle age group
mean § SD
Old age group
mean § SD
Lengths (mm)
Cord of radiocarpal joint arc (BE)
28.9 § 2.7
29.3 § 2.3
Radius of radio-carpal
joint arc
36.75 § 5.2
38.4 § 8.6*
1.65 § 0.5
1.35 § 0.5**
0.41 § 1.4
0.39 § 1.5**
Distal radio-ulnar
joint space
Ulnar variance (UV)
Lunate uncovered
length
Length of capitate
Carpal height (CH)
Carpal–ulnar
distance (CUD)
Carpal–radial
distance (CRD)
Length of third
metacarpal
Radial length
Lunate fossa
inclination (LFI)
5.85 § 2.3
21.95 § 2.2
33.85 § 3.4
17.2 § 3.4
19.45 § 1.8
64.6 § 5.0
12.25 § 0.3
12.86 § 0.6
5.95 § 2.1
21.0 § 2.1
34.45 § 8.0**
17.45 § 3.2
19.25 § 1.6
63.9 § 3.9**
12.25 § 0.21
12.85 § 0.71
Indices
Carpal height
ratio (%)
52.6 § 3.8
55.1 § 3.5*
Alternative Carpal
height ratio
1.54 § 2.3
1.45 § 3.1
Cord of radio-carpal
joint arc (BE)
Length of distal
radio-ulnar joint
1.65 § 0.7
1.35 § 1.0
Ulnar variance (UV)
Lunate uncovered
length
0.41 § 1.4
6.55 § 3.0
39.5 § 1.6*
Length of capitate
22.6 § 2.7
20.35 § 2.1*
Carpal–ulnar
distance (CUD)
18.8 § 2.9
15.85 § 4.0*
Carpal–radial
distance (CRD)
20.2 § 2.4
18.5 § 1.9*
Length of third
metacarpal
65.7 § 5.7
62.8 § 4.3*
Carpal height (CH)
Radial length
Lunate fossa
inclination (LFI)
Carpal height ratio (%)
Alternative Carpal
height ratio
Carpal–ulnar
ratio (%)
Lunate uncovering
ratio (%)
28.6 § 5.0**
Lunate uncovering
ratio (%)
32.65 § 9.8
33.2 § 12.1
Radius-third
metacarpal (RMA)
30.7 § 2.2
30.9 § 2.4
Radius-capitate (RCA)
0.60° § 6.1
0.61° § 5.0
Radius-third
metacarpal (RMA)
Radius-capitate (RCA)
Radial inclination (RI)
1.6° § 10.4
25.5° § 7.1
1.5° § 9.8
27.1° § 6.8*
*P < 0.0001
**P < 0.005
and the carpal height ratio (P < 0.001) and the angle of
radial inclination (P = 0.01). Finally, there was a signiWcant
relationship between the lengths of the capitate and the
third metacarpal and the height and lengths of the capitate
and the third metacarpal (P < 0.001).
Discussion
The roentgenographic morphology of the wrist has been
described in textbooks [4, 17] and in articles [9, 18]. The
27.2 § 1.3*
37.6 § 8.0
27.75 § 5.3
Angles (°)
31 § 2.0
Females
mean § SD
37.55 § 6.3
Radius of radio-carpal
joint arc
Carpal–ulnar
ratio (%)
Carpal–radial
ratio (%)
Males
mean § SD
Carpal–radial ratio (%)
Radial inclination (RI)
35.8 § 6.0
13 § 0.7
13.61 § 3.0
52.3 § 6.3
5.25 § 2.8*
32.5 § 5.1*
11.5 § 0.81*
12.1 § 3.6**
53 § 7.0
1.46 § 2.1
1.44 § 1.8
29.7 § 7.0
26.65 § 8.4*
33.05 § 11.2
33.5 § 12.9
31.4 § 3.1
29.6 § 2.7*
0.7° § 4.0
1.05° § 10.2
28.1° § 8.1
0.6° § 3.6
1.6° § 9.7
24.5° § 5.9*
*P < 0.0001
**P < 0.005
progression of degenerative disease, carpal instability, osteonecrosis, and osteoarthrosis can be followed by notation of
the changes in the radiographic carpal bone measurements
[9]. The position of the wrist, forearm, and arm as well as
the orientation of the X-ray beam, has been shown to aVect
the appearance and location of the osseous landmarks and
this in turn can aVect the measurements [6, 19]. In this
study we used true PA radiograph in the neutral position as
this position can be adjusted easily in living persons as well
as in corpses in order to obtain accurate measurements [6].
The results of this study clariWed that bony structures
forming wrist showed age and sex related diVerences and
most of these diVerences were proven to be signiWcant.
These diVerences were those related to lengths including
width (length) of distal radio-ulnar joint space, ulnar variance, radius of radio-carpal joint arc and length of third
123
672
Table 5 Relationships between
the anatomical parameters
Surg Radiol Anat (2009) 31:665–674
Anatomical parameter
Y
X
P value
R2
Regression
equation
Height
Length of capitate
<0.001
0.47
Y = 0.71 + 0.34X
Height
Length of third
metacarpal
<0.001
0.48
Y = 0.70 + 0.32X
Length of capitate
Length of third
metacarpal
<0.001
0.47
Y = 0.71 + 0.33X
Ulnar variance (UV)
Lunate uncovering
ratio
<0.01
0.09
Y = ¡3.49 + 0.l3X ¡ 0.001X2
Carpal–ulnar ratio
Carpal height ratio
<0.001
0.13
Lunate uncovering
ratio
Carpal–ulnar ratio
<0.01
0.04
Y = ¡10.1 + 0.95X ¡ 0.005X2
Carpal–radial ratio
Carpal height ratio
<0.01
0.06
Y = 16.86 + 0.25X
Carpal–radial ratio
Radial inclination (RI)
<0.01
0.06
Y = 26.90 + 0.14X
metacarpal. Also ratios related to length measurements
were aVected including carpal height ratio, alternative carpal height ratio and lunate uncovering ratio. Radial inclination was the most aVected angle that showed age and sex
related signiWcant diVerences. These results are in accordance with similar results reported by Crisco [20] and by
Gonzalez [21] on their study on Mexicans.
The Wnding concerning the carpal height in our study is
of such relevance, that it can inXuence in the cut point used
to specify with respect to sex the criteria for the disease of
Kienböck, as well as for the traumatic aVections of
scaphoid that cause carpal collapse. These statistically signiWcant diVerences between men and women contribute
partly to explain the greater incidence of carpal tunnel syndrome in females as reported by Elveback Lila [22]. The
decreasing in dimensions of bones could approximate the
bones to each other, and this in turn; make the carpal tunnel’s edges nearer to each other and trapping of the nerve
easier to occur.
Nattrass [14] refers three training groups (corpses, normal and patient people with rheumatoid arthritis), in which
they existed statistically signiWcant diVerences in the carpal
height, with a smaller average for the group with rheumatoid arthritis. The result of the length of the third metacarpal in our study was in parallel with those reported by
Schuind [9] and Gonzalez [21] and contrary to those two
studies which showed values without diVerences with
respect to sex [22, 23]. This measurement is necessary to
realize that some indices work to determine carpal collapse,
as well as stops ulnar deviation of the carpus. The carpal
height ratio in this study nearer is to that described by Schuind [9] and Gonzalez [21] but diVer a little to those demonstrated by Stahelin [13] and McMurtry [24]. The method of
positioning of the wrist when the roentgenograms are made
aVects the measurements. We kept the wrist in a neutral
position; Stahelin [13] placed the entire palm Xat on the
123
Y = ¡16.1 + 3.7X ¡ 0.07X2
table, which kept the wrist in palmar Xexion with apparent
shortening of the length of the third metacarpal which is not
the case in this research, as we kept the wrist in neutral
position.
This measurement is useful to evaluate the clinical evolution of the patients with disease of Kienböck, as well as
the patients with rheumatoid arthritis, as much presurgical
arthritis. Nattrass [14] publishes in Canada an alternative
method for measurement of the carpal height ratio, with
the use of the length of the capitate bone (alternative carpal height ratio); in his group healthy control with result of
1, 57 § 0, 05 and in the group with rheumatoid arthritis of
1, 40 § 0.11. In our study we had a 1.53 § 0.16 for males
and 1.55 § 0.21for females in the middle age group which
are in the normal range of healthy controls while we had
1,46 result § 0,16 for males and 1.44 § 0.21 for females
in the old age group. It would be excellent to consider this
parameter in our population to measure the carpal collapse, since our values in healthy subjects in the old age
group were similar to the parameters described by Nattrass
[14] for subjects with rheumatoid arthritis, which could
aVect to healthy subjects misdiagnosing them to be
patients.
Conditions of carpal collapse are frequently associated
with ulnar translocation that can be evaluated by estimation
of the carpal–radial and carpal–ulnar ratios. The index of
carpus–ulnar distance with third metacarpal (carpal–ulnar
ratio) in our study was in average to reported by Schuind
[9].The angle of radial inclination is commonly used to
assess the adequacy of the reduction of fractures of the distal end of the radius [25]. The angle of radial inclination
reported here similar to that demonstrated by Taleisnik [5]
and Schuind [9] but contrary to Gonzalez [21] we found a
statistically signiWcant diVerence between two sexes. Ethnographic factors may explain these diVerences. DiBenedetto [26] demonstrated a correlation between the changes in
Surg Radiol Anat (2009) 31:665–674
the angles of radial inclination and non-dissociative patterns of carpal instabilities.
It has been found by Schuind [9] the only signiWcant
related change in the anatomy of the wrist according to age
was related to width (length) of distal radioulnar joint space
while those related to sex included those measurements
related to lengths. The diVerences related to age could be
attributed to degenerative changes [27]. This could be conWrmed by that; ulnar variance showed age related signiWcant diVerence as has been reported previously that people
who are between 45 and 60 showed degenerative changes
in the triangular Wbrocartilage causing changes in the ulnar
variance [28]. The results of this study are similar to Crisco
[20] who reported that all of the measurements of the carpal
bones and joints were shorter in women suggesting that the
wrist is relatively narrower in women.
Unlike the results of this study, Tornvall [19] in their
study reported that ulnar variance to be the same in both
sexes and Tanaka [29] who found that ulnar variance to be
smaller in men than women. This could be related to the
fact that ulnar variance demands a standard radiographic
technique with standard positioning of the arm, since
ulnar variance changing with pronation and supination
[6]. These diVerences may also be due to ethnographic
factors.
Our results are in accordance with that reported by
Gonzalez [21] and Baratz and Larsen [30] and contrary to
the results reported by Taleisnik [5] who documented that
there was no relationship between ulnar variance or carpal
height and the age of the subjects, even when men and
women were evaluated separately.
Conclusion
Our study documents the normal roentgenographic measurements, relationships and variations according to age
and sex between the bones of the wrist among Egyptians
serving as a reference point. It also can be used to follow
the progression of carpal instabilities, osteonecrosis, osteoarthrosis, or rheumatoid arthritis, in clinical research and in
the design of wrist implants.
Acknowledgments We would like to thank Dr. Tarek Abd El Aziz,
assistant professor of Orthopedic, faculty of medicine, Suez canal university, Ismailia, Egypt for his help in choosing the proper subjects for
the study, and Dr. Amany Wahid, assistant professor of community
medicine, faculty of medicine, Suez canal university, Ismailia, Egypt
for her great help in doing statistical analysis of this study.
References
1. Farkas LG, Munro IR (1987) Anthropometric facial proportions.
In: Medicine. Charles C Thomas, SpringWeld, p 344
673
2. Bidmos MA, Asala SA (2004) Sexual dimorphism of the calcaneus of South African blacks. J Forensic Sci 49:446–450
3. Franklin D, Freedman L, Milne N (2005) Sexual dimorphism and
discriminate function sexing in indigenous South Africans. Homo
55(3):213–228
4. Linscheid RL (1986) Kinematic consideration of the wrist. Clin
Orthop 202:27–39
5. Taleisnik J (1985) Radiographic examination of the wrist. In: The
wrist. Churchill Livingstone, New York, pp 79–104
6. Cassandra R, Randy EE, Tom G et al (2002) The sensitivity of carpal bone indices to rotational malpositioning. J Hand Surg
27A:435–442
7. Gilula LA, Weeks PM (1978) Post- traumatic ligamentous instabilities of the wrist. Radiology 129:641–651
8. Mann FA, Kang SW, Gilula LA (1992) Normal palmar tilt is dorsal tilting really normal? J Hand Surg 17B:315–317
9. Schuind FA, Linscheid RL, Chao EYS (1992) A normal data base
of posteroanterior roentgenographic measurements of the wrist.
J Bone Joint Surg 74A(9):1418–1429
10. Belsole RJ (1984) Radiography of the wrist. Clin Orthop 187:52–64
11. Meschan Isadore MA (1990) Radiographic positioning and related
anatomy, 2nd edn. W.B. Saunders Company, Philadelphia
12. Youm Y, McMurtry RY, Flatt AE et al (1987) Kinematics of the
wrist I. An experimental study of radio-ulnar deviation and Xexion-extension. J Bone Joint Surg 60A:423–431
13. Stahelin A, PfeiVer K, Senwald G et al (1989) Determining carpal
collapse. An improved method. J Bone joint Surg 71A:1400–1405
14. Nattrass G, King G, McMurtry R et al (1994) An alternative method for determination of the carpal height ratio. J Bone Joint Surg
76A:88–94
15. Thienpont E, Mulier T, Rega F et al (2003) Radiographic analysis
of anatomic risk factors for scapholunate dissociation. Acta Orthop Belg 69(3):246–251
16. Nakamura R, Hori M, Imamura T et al (1989) Method for measurement and evaluation of carpal bone angles. J Hand Surg
14A:412–416
17. Destouet JM, Gilula LA, Remus WR (1988) Roentgenographic
diagnosis of wrist pain and instability. In: Lichtman DM (ed) The
wrist and its disorders. W. B. Saunders, Philadelphia, pp 82–95
18. af Ekenstam F, Hagert CG (1985) Anatomical studies on geometry
and stability of the distal radioulnar joint. Scand J Plast Reconstr
Surg 19:17–25
19. Tornvall AH, af Ekenstam F, Hagert CG et al (1986) Radiologic
examination and measurement of the wrist and distal radio-ulnar
joint. New aspects. Acta radiol Diagn 27:581–588
20. Crisco JJ, Coburn JC, Moore DC et al (2005) Carpal bone size and
scaling in men versus in women. J Hand Surg (Am) 30(1):35–42
21. Gonzalez TR, Valencia FM, Figueroa SF (2006) Radiographic
measurements of the wrist in healthy Mexicans. Cir Cir
74(5):335–342
22. Elveback L (1973) The population of healthy persons as a source
of reference information. Hum Pathol 4:9–16
23. Linscheid RL, Dobyns JH, Beabout JW et al (1972) Traumatic
instability of the wrist. Diagnosis, classiWcation, and pathomechanics. J Bone Joint Surg 54A:1612–1632
24. McMurtry RY, Youm Y, Flatt AE et al (1978) Kinematics of the
wrist II. Clinical applications. J Bone Joint Surg 60A:955–961
25. Schuind F, Donkerwolcke M, Rasquin C et al (1989) External Wxation of fractures of the distal radius: a study of 225 cases. J Hand
Surg 14A:404–407
26. DiBenedetto MR, Lubbers LM, Coleman CR (1991) Relationship
between radial inclination angle and ulnar deviation of the Wngers.
J Hand Surg 16A:36–39
27. Zanetti M, Gilula LA, Jacob HAC et al (2001) Palmar tilt of the
distal radius: inXuence of oV-lateral projection-initial observations. Radiology 220:594–600
123
674
28. Epner RA, Bowers WH, Guilford WB (1982) Ulnar variance—the
eVect of wrist positioning and roentgen Wlming technique. J Hand
Surg 7:298–305
29. Tanaka Y (1989) Ulnar variance. A study of ulnar variance. J Jpn
Soc Surg Hand 6:120–130
123
Surg Radiol Anat (2009) 31:665–674
30. Baratz ME, Larsen CF (1996) Wrist and hand measurements and
classiWcation schemes. In: Imaging of the wrist and hand. Saunders, Philadelphia, pp 225–259