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Transverse sections of the elbow region in man made into transparencies and embedded in plastic in a self-study module.

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THE ANATOMICAL RECORD 210:541-547 (19841
Transverse Sections of the Elbow Region in Man, Made Into
Transparencies and Embedded in Plastic in a Self-study Module
L.M.A. LATASTER, J.W. RENSEMA, H. VAN MAMEREN,
AND J. DRUKKER
Capacity Group Anatomy/Embrydogy, Faculty of Medicine, National
University of Limburg, I? 0. Box 616, 6200 MD Maastricht, The
Netherlands
ABSTRACT
This paper describes a valuable tool for medical teaching. It is
a detailed description of a method to present transparent sections embedded in
plastic, placed in a self-instruction module by means of a vertical storage
system. It includes the use of three-dimensional graphic reconstructions. Other
applications are also indicated.
The medical school of the National University of Limburg a t Maastricht is recently
founded (1975).
The curriculum of this school differs in
some respects from that of older schools. It
puts a heavy emphasis on the self-activity of
the students; in other words, the curriculum
is student-centered and not docent-centered.
A second characteristic of the curriculum is
that it is not subject-based but problem-based.
This means, among other things, that disciplines do not occur as separate entities in the
curriculum, but that the educational offer to
students is of multidisciplinary character.
The study of medical problems of related
nature is clustered into blocks of 6 weeks.
For each period a block book is constructed
in which the problems are assembled. The
docent is to procure the means by which the
student can try to achieve the set goals without any emphasis on direct contact between
docent and student. The goals derived from
each problem during a given block may belong to different disciplinary territories.
Moreover, the assessment of increase in
knowledge and insight is again a primary
task of the student. The teacher has to offer
the facilities for self-evaluation. It is mentioned here in parentheses that next to this
formative evaluation, there exists a system
of summative evaluation. This educational
strategy demands a n entirely different attitude from the teacher as compared with the
situation in docent-centered, subject-based
curricula. It will be clear that especially for
gross anatomy, an educational policy as outlined above poses serious difficulties (Drukker et al., 1981).The anatomist has to expose
students, or rather give students the oppor0 1984 ALAN R. LISS. INC.
tunity to expose themselves, to situations in
which they can improve upon their knowledge of anatomy without relying on formal
lecturing andor formal labs where the body
is systematically dissected or where prosected specimens allow for discipline-oriented studies.
Other resources have to be developed
therefore.
The study of (consecutive) transparent sections offers a unique opportunity to work independently on enhancing one’s insight in
the third dimension, given the understanding that the sections are accompanied by
adequate explanation. Whereas sections
comprise all elements in topographical arrangement, the quality of the accompanying
text influences the direction and the level at
which they are used. The nature of the multidisciplinary problem can thus define the
specific use of the sections in a given case.
The sections should be offered to the students in such a way that their setting fulfils
at least some of the following characteristics:
1) they should allow for, rather stimulate,
docent-independent learning
2) they are to make self-evaluation possible
3) they should be “student-proof’
4) their construction should not be too
time-consuming
5 ) they should have some versatility
6 ) they should consume as little space as
possible
7) they should not be too expensive.
Apart from this set of educational and constructional criteria it should of course be
Received February 13, 1984; accepted June 5, 1984
L.M.A. LATASTER ET AL.
542
\
t’
.
\
V
Fig. 1. The plastic embedding procedure of the anatomical sections. a) The covering of the embedding. b)
The unfinished mounting. A, acrylic embedding con-
tainer; 1,2,3, several layers of catalyzed polyester resin;
B, anatomical section; C, acrylic covering container; D,
line at which the rims of the mounting are sawn off.
stated that the learning goals that can be We made use of a method which has been
attained with such resources must match the developed to preserve transverse sections.
objectives the school has formulated for the They were made transparent by applying
phase of the curriculum in which the stu- methylsalicylate (2-hydroxybenzoic acid
dents are confronted with a given resource.
methyl ester; oil of Wintergreen) according
In the following we will describe the design to Spalteholz (Piechocki, 1979).Subsequently
and construction of a learning resource which they were embedded in polyester resin (Lafulfils most of the given criteria. This has taster and van Mameren, 1983).
been given the appearance of a n educational The plastic embedding is necessary to make
module (Pallie and Brain, 1978; Mc. Phee- the transparent sections accessible as a
ters, 1979).
learning resource because the vapor of methAs a n example the elbow region has been ylsalicylate is harmful to the health. Morechosen.
over the latter preserving method is very
A METHOD FOR TEACHING GROSS ANATOMY
543
Fig. 2. One slide containing six sections and pulled in
front of the display-screen by means of a A) ball-bearingsupported telescopic rail system. In front of the slide a
panel is mounted by means of B) one pair of hinges and
C ) one pair of hook and loop fasteners. On the panel a
space-consuming. Since the embedding procedure must preserve the translucency of the
sections it is obvious that the mounts have
to be as thin as possible, creating two
problems:
1) the mounts become fragile
2) it has to be possible to study them one
by one in front of a display-screen or
some other type of transilluminating
light source.
This shows clearly the necessity for the
special way of presentation described in this
paper.
been fully described elsewhere (Lataster and
van Mameren, 1983).
Transparent sections with a thickness of
0.4 cm are embedded in catalyzed polyester
resin which is poured in a n acrylic container.
After hardening the embedding is covered by
a second, somewhat smaller, acrylic container in a way that resembles the covering
of a microscopical section (Fig. la). Consequently the rims of the hardened mounting
are sawn off a t the inner side of the raised
border of the smallest container to complete
the mount (Fig. lb). The thickness of the
finished mounts is approximately 1.1cm.
After this the mounts are placed in a vertical storage system containing 1)a cassette,
2) an undercarriage, and 3) a guiding system.
1) The cassette is made of 0.15 cm steel
plate (37)with a white, baked-on finish. Each
mount is placed vertically in the cassette by
DESIGN AND BUILDING OF A VERTICAL
STORAGE SYSTEM
Before we describe the design and building
of the vertical storage system it is necessary
to give a summary of the embedding method
developed by two of the authors, which has
key is written.
544
L.M.A. LATASTER ET AL.
-1
3
a
Fig. 3.a) Oblique view on the guiding systedundercarriage: 1, aluminum strip; 2, aluminum front piece; 3 ,
aluminum back piece; 4,ball bearing chamber; 5, steel
axle; 6 , aluminum supports (halfway on the table); 7,
aluminum strip notched on the underside; 8, springtensioned ball bearing resting in an aluminum support.
b) Median-section of the spring-tensioned ball bearing
resting in an aluminum support. 1,spring.
means of a ball-bearing-supported telescopic
rail system (“gliders”; see Fig. 2). Mounted
in front of each slide is an acrylic panel (0.2
cm thick), attached on one side by means of
a pair of hinges and on the other side with
hook and loop fasteners at each corner (Fig.
2). On the panel a key is written by means of
a waterproof felt-tipped pen. The referral
lines are drawn on the backside to minimize
paralax. When the slide is pulled in front of
the display screen this panel can be turned
away.
2) The cassette is mounted on top of a n
undercarriage by means of wing nuts to make
it convertible. The undercarriage consists of
a) an aluminum front piece containing two
ball bearing chambers, b) an aluminum back
piece containing two ball bearing chambers,
c) two aluminum strips connecting the front
and back pieces, and d) a n aluminum strip
notched at the underside and mounted as
indicated in Figure 3a.
3) The undercarriage makes a gliding motion along the guiding system, which consists
of a) four aluminum supports; b) two steel
axles, and c) four stops; each consists of a
metal ring with Allen screw, a rubber ring
(to absorb shocks), and a ring of PerspexR; d)
one spring-tensioned ball bearing resting in
a n aluminum support. Two supports are
mounted at the front and the back of a table,
the other two halfway between (Fig. 3a). The
axles are mounted in the front and back supports and rest upon the other two (Fig. 3a).
The stops are necessary to determine the
range between which the undercarriage is
able to move. The gliding motion is possible
by means of the above-mentioned ball bearing chambers of the guiding system enclosing the axles. The cassette can be moved
forward and backward with a handle. The
spring-tensioned ball bearing resting in a n
aluminum support (Fig. 3a,b) corresponds
with the notches of the above-mentioned strip
of the undercarriage and enables the undercarriage to be fixed in a position that allows
the slide to be as close a s possible to the front
of the display-screen. There is one notch for
each mount.
The complete vertical storage system is
placed on top of a table (200 x 100 x 75 cm)
with a working surface made of TrespaR (1.8
cm thick). On the table are placed, further,
drawn reconstructions of the specific structures in the sections, a display-screen for xrays, acrylic containers to store separated
and articulated bones, x-rays, hard copies of
C.T. scans, scripts, textbooks, keys, etc. (Fig.
4), and a construction made of pieces of foursided chromed steel tubing (2.5 x 2.5 cm),
couplings (T-shaped, corner-shaped, etc.), and
planks made of TrespaR to store models, etc.
DISCUSSION
To obtain insight into the morphology of
the human body several learning resources
are available to medical students. Besides
the “classical” approach of dissecting the hu-
A METHOD FOR TEACHING GROSS ANATOMY
Fig. 4. The complete module, including A, cassette;
B, guiding systemhindercarriage; C, display-screen; D,
acrylic containers to store (1) x-rays and hard copies of
C.T. scans, (2) scripts, text-books, keys, etc., and ( 3 ) sep-
man body in a systematic way (which is not
done in our department except by students
who take this a s an elective) several other
audiovisual media are used.
The following list is a summary of the advantages of using transparent sections as a
learning resource. The advantages of anatomical sections generally have recently also
been stressed by others (Peppler et al., 1983;
Boushey and Stultz, 1983).
The Use of a Vertical Storage System
The advantage of using a vertical storage
system in presenting the embedded sections
is that they are surveyable, which means
that they can easily be studied systematically.
The impact-free storage is necessary because of the fragility of the thin mounts (they
545
arated and articulated bones; E, display-screen for xrays; F, construction made of pieces of four-sided chromed
steel tubing, couplings, and planks.
have to be student-proof) (Bridgman and
Hummelbaugh, 1963). The possible need to
store a large number of mounts demands a
compact design of the cassette. It must be
assembled on top of a n undercarriagelguiding system to allow one to study the mounts
one by one with transilluminating light in
front of a display-screen.
Because of the heavy load, the construction
and the moving parts of the undercarriage
must be strong.
The Use of a Convertible Cassette
It may be profitable to change the contents
of a module. For that reason the cassette
should be convertible. Such a conversion can
be done quickly by using wing nuts. The use
of a limited number of frameworks to house
a larger number of modules decreases the
546
L.M.A. LATASTER ET AL.
Fig. 5. Detail of the module showing the vertical storage system with one slide pulled in front of the displayscreen and the key panel moved away. A, Three-dimen-
sional graphic reconstructions of t h e bony anatomy of
the elbow region seen from two directions.
costs as compared to the costs of the permanent presentation of all modules in their own
framework.
sidered to be too time absorbing, the (self)
study of sections offers a good alternative.
A number of drawings that have been made
to reconstruct the series of sections give a
clearer understanding of their mutual relation. These drawn reconstructions show the
sequence of a series of cross sections in perspective with their serial numbers indicated.
A number of separate structures are reconstructed also, such as the bony anatomy (Fig.
5), the muscles, the connective tissue system, etc.
The transparent sections are not only useful in teaching at the undergraduate and
graduate level. They can-with a n adequate
description-also meet the needs of postgraduate training or of continuing education of
health-care professionals.
This especially holds true for the training
which is offered by the self-study of consecutive sections through a given region of the
The Possibility of Self-Evaluation
The fact that the sections are labelled by
placing movable PerspexR panels covered
with text in front of each plastic mount, attached on one side by means of a pair of
hinges, makes the mounts suitable for selfevaluation: when the panels are moved away,
the students can study the sections and are
able to check their knowledge (Fig. 5).
The Worth of Transparent Sections
The advantage of using transparent sections is the ability (in combination with other
specimens) to obtain complete awareness of
all spatial relations.
Where nowadays the dissection of the entire body by each student is frequently con-
A METHOD FOR TEACHING GROSS ANATOMY
body for those who have to orient themselves
in sections, e.g., in C.T. scans of that region.
Though the system has been devised as a
consequence of the needs induced by the
teaching in a student-centered, docent-independent system, it is emphasized that it is
useful as well in all kinds of teaching situations, especially in small groups, whether or
not in the presence of a teacher.
The Construction Time
The estimated net production time required to construct the various parts of the
described module amounts to cassette 40
hours, undercarriage and guiding system, 40
hours, framework 50 hours, embedding procedure 50 hours, and overlays 40 hours.
If one wishes to cover the cross-sectional
anatomy, making use of transparent sections
in vertical storage systems, our estimation is
that about 1,800 hours will be needed.
The development of this learning resource
has shown to us the necessity of the collaboration of experts in several disciplines (Evans and Eldridge, 1978). In this particular
case a medical doctor, a head of the dissection
room, a n instrument-maker, and a medical
artist were involved.
ACKNOWLEDGMENTS
The authors are indebted to Th. Gulikers
(instrument-maker) for his technical advice
547
and building both the framework and the
vertical storage system for the mounts.
LITERATURE CITED
Boushey, D.R., and W.A. Stultz (1983) The preparation'
of human cross sections. Anat. Rec., 207t379-383.
Bridgman, C.F., and F.A. Hummelbaugh (1963) Plastic
embedded specimens in medical teaching. Med. Biol.
Ill. 13t177-185.
Drukker, J., H. van Mameren, H.W.M. van Straaten, F.
Thors, J.C. van der Wal, E.L.M.J. Wiertz-Hoessels, and
W.G.M. Witkam (1981) The teaching of anatomy in a
non-traditional medical curriculum. Acta Anat.,
lllt35-36.
Evans, E.M., and W.S. Eldridge (1978) Audiovisual media, a combined operation. J. Audiovis. Media Med.,
1:140-142.
Lataster, L.M.A., and H. van Mameren (1983) Eine
Methode zur Einbettung von Aufbellungspraparaten
in Kunstharz. Praparator, 29:165-172.
Peppler, R.D., T.E. Kwasigroch, and M.W. Hougland
(1983) Cross-sectional anatomy: preparation of teaching specimens. Anat. Rec., 206:341-344.
Mc. Pheeters, V. (1979) Learning resource centers-past,
present and future. J. Audiovis. Media Med., 2:173174.
Pallie, W., and E. Brain (1978) Modules in morphology
for self study: a system for learning in a n undergraduate medical programme. Med. Educ., 12:107-113.
Piechocki, R. (1979): Makroskopische Praparationstechnik, 3e Auflage. Gustav Fischer Verlag, New York, Vol.
I Wirbeltiere, pp. 245-272.
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