Studies of the Upper-Extremity Amputee III. The Treatment Process
Warren P. Springer, M.A.†
The amputees who took part in the NYU Upper-Extremity Field Studies obtained
their new prostheses through a treatment process characterized by seven
clear-cut steps. These were preprescription examination, prescription,
preprosthetic therapy (if indicated), fabrication of the prosthesis, initial
checkout, training, and final checkout.
The preprescription examination was conducted at the beginning of the
treatment process in order to obtain information that would be useful in
formulating the prescription and planning the entire treatment program for the
As for prescription, the research and educational program strongly encouraged
the clinic-team approach, wherein the physician, as clinic chief, involved the
prosthetist, the therapist, the patient, and frequently other individuals, such
as the social worker or the vocational counselor, in the prescription process.
The resulting prescription not only covered the strictly medicosurgical aspects
of management but also specified the type of prosthesis and components that were
to be used and the training the patient was to receive.
The preprosthetic phase of treatment, when indicated, was directed toward
providing the patient with the necessary strength and range of motion to operate
his prosthesis and toward conditioning his stump for wearing it.
In the fabrication process, the prosthetist, working with the patient,
carried out the construction and fitting of the prosthesis in accordance with the specifications
of the prescription.
Initial checkout, which was done on a team basis, consisted of a systematic
inspection and evaluation of the prosthesis to ensure that accepted standards of
construction and function were achieved. This step was accomplished before the
amputee received training and before he was permitted to wear his prosthesis for
any extended period.
Training consisted essentially of two partsócontrols training and use
training. The purpose of controls training was to develop the ability to open
and close the terminal device, control prehension force, operate the wrist unit,
interchange terminal devices, and, in the above-elbow cases, flex the prosthetic
elbow and operate the elbow lock. Use training was designed to develop the
ability to utilize the prosthesis in practical tasks related to daily-living
activities and to occupational requirements.
Final checkout was performed after the completion of training or after an
initial period of wear. It paralleled initial checkout in that many
biomechanical evaluation procedures were repeated to determine if wear had given
rise to any difficulties or deficiencies. But in addition to the evaluation of
the prosthesis itself final checkout also included an evaluation of training and
of the amputee's ability to use the prosthesis at a practical level.
This paper is primarily an account of the experiences and opinions pertaining
to the treatment process as obtained from interviews with 359 adult, male amputees
both at the beginning and at the end of their participation in the studies. The
information concerning checkout and training is supplemented by clinical data from
records of an additional 410 amputees who participated in clinical aspects of the study.
The general characteristics of the research group of 359 amputees closely
parallel those of the 1630 amputees in the survey group (Section II). Between
the two groups there were no significant differences with respect to age,
height, weight, marital status, cause of amputation, or strength and range of
motion on the side of the amputation, although there were slight differences in
educational level, in experience with arm prostheses, and in the relative
frequency of below- and above-elbow types.
In interpreting the data in this section, certain considerations should be
kept in mind. First of all, a considerable portion of the information is based
on the amputees' recollections of past events. The differences that may exist
between the recollection of events and the events as they actually happened
constitute a possible source of error. A second consideration has to do with the
amputees' interpretations of the questions asked during the interviews,
especially at the beginning of the study. Terms such as "clinic,"
"prescription," "checkout," "physical therapy," and "training" may have had
widely varying meanings for different subjects. For example, a subject might
have said that the prosthesis he was wearing at the beginning of the study had
been subjected to a checkout when in reality it had been given only a cursory
inspection instead of the systematic examination and evaluation that constituted
a "checkout" in our meaning of the term.
A third factor has to do with the number of amputees who were able to give
meaningful responses to these questions. In some instances and for various
reasons usable responses were not obtained from the entire group. In some cases
questions were not answered. In most instances, however, classifiable responses
were obtained from at least 80 percent of the group, and it seems reasonable
that these responses are representative of the attitudes of the entire
On the positive side, there is good reason to assign a considerable degree of
importance to the opinions and reactions expressed by the subjects, since, in
the last analysis, the amputee is the final judge of his prosthesis. The extent
to which he accepts and approves of the process through which he obtains his
prosthesis may have considerable bearing on the extent to which he accepts and
uses the device.
Prior to their participation in the research studies, only 17 percent of the
amputees had ever received an arm that was prescribed by a clinic team
(physician, limbfitter, and therapist). In the great majority of cases,
decisions as to the type of limb and components had been made either on an
individual basis by the limbfitter or the amputee or jointly by both limbfitter
and amputee. Fifty-six percent of the amputees approved of this procedure, the
most frequent reason (21 percent) given for approval being that they were
consulted concerning their choice.
In the group (44 percent) that did not approve of the preprogram procedure
through which they had received a limb, 14 percent reacted negatively to the
fact that they were not consulted. It was somewhat surprising to find that an
additional 18 percent expressed the opinion that the amputee should not be
consulted. Of the total group, 12 percent felt that the doctor should prescribe
the prosthesis. Apparently a significant number of amputees prefer to trust the
judgment of others in the matter of prosthetic replacement. Others (and the
number probably increases with their prosthetic experience) prefer to become
personally involved in the selection of components best suited to their
Since all of the prescriptions for the new prostheses and related treatments
were arrived at on a clinic-team basis, the amputees were asked the following
question to obtain their reactions to the team method of prescription: Do you
think that prescription of a new arm by a clinic consisting of a doctor,
limbfitter, and therapist is a good procedure? Ninety-four percent of the
amputees answered in the affirmative. Compared to the mixed reactions concerning
the preprogram procedures, the figure of 94 percent clearly indicates that the amputees preferred the new
procedure. By far the most frequent reason given for this response was that the
combined experience which could be obtained through the clinic procedure was
useful. Typical comments were:
". . . more heads are better than one."
". . . experience of several people is helpful."
". . . no aspect is overlooked."
Other reasons that were mentioned relatively frequently can be classified
under these headings:
". . . prevents errors."
". . . team members act as a check on each other."
". . . amputee becomes involved in the prescription."
Among the 6 percent who did not approve of the procedure, the most common
reason offered was that:
"An old wearer knows what he needs."
To obtain information on the parts the various clinic members played in
prescription, the amputees were asked: Who was most influential in deciding the
kind of arm you should havef The replies are summarized in the accompanying
The next two charts show the relative frequency with which the various types
of terminal devices were prescribed in the research study. For purposes of
comparison, data on the hands and hooks that were being worn at the beginning of the study are included under the heading "Old Prosthesis."
In interpreting the prescription data on hands and hooks, consideration
should be given to the fact that it was a policy of the research program to
encourage the prescription of APRL hands and hooks in order to obtain additional
data for evaluation of these devices. This accounts for part, but by no means
all, of the changes in terminal components of the old and the new prostheses.
Other factors involved in the changes were related to an increasing tendency on
the part of clinic groups to prescribe aluminum hooks and hooks with rubber or
neoprene facings and to a natural interest in the possibilities of
voluntary-closing terminal devices with their wide range of grasp forces. In the
case of the APRL hand, the wide range of grasp forces was combined with improved
appearance. This natural curiosity and interest in new devices is reflected in
the increased use of the Sierra two-load hook also.
The new prostheses showed a marked increase in the prescription of
positive-locking wrist units with the "quick-change" disconnect. The chief
reasons for this increase related to:
- Specific vocational or avocational indications for a positive
lock to control rotation.
- Prescription of both hand and hook for approximately four out of
five subjects. A substantial majority of these cases required a wrist unit with
a "quick-change" feature to facilitate interchange of hand and hook. (Fig. 1)
There were only two wrist-flexion units on the old prostheses. Both cases
were bilateral amputees. Twenty-two wrist-flexion units were prescribed in the research group. Ten were for bilateral amputees; six were
for above-elbow, four for shoulder-disarticulation, and two for below-elbow
amputees. (Fig. 2, Fig. 3)
A marked increase in the number of flexible hinges prescribed reflects the
increased awareness of the value of utilizing residual rotation of the forearm
stump whenever possible so that the need for pre-positioning the terminal device
with the sound hand can be reduced or eliminated entirely. An additional
advantage of flexible hinges is that they are less likely to damage the sleeves
of the wearer's clothes.
Prescription for below-elbow cuffs showed a marked change toward smaller
cuffs and elimination of straps. This change is a result of increased
recognition of the desirability of providing a cuff large enough to give
adequate stability and suspension but which would also have minimum bulk, would
restrict motion as little as possible, and would give greater comfort.
A guiding principle in the prescription of prosthetic elbow units for
above-elbow and shoulder-disarticulation prostheses was that locking should be
accomplished independently by controls attached to the harness, without recourse
to operation of controls by the sound hand. The extent to which this principle
was applied can be seen from the data, which show that all elbow units
prescribed were harness-operated. This is a highly significant change from the
data relating to the old prosthesis, which show that only 46 percent of the old
elbow units were harness-operated.
Practically all of the prescriptions for the new prostheses specified plastic
laminate as the material to be used in fabricating the socket. The data on the
socket material used in the old prostheses show that 37 percent were made of
plastic, 28 percent were made of leather with a steel frame, and the remainder
were made of fiber and metal, wood, or leather. Approximately four out of five
of the new prostheses had double-wall sockets, as compared to less than one out
of five of the old prostheses. Twelve percent of the old and 14 percent of the
new below-elbow sockets were of the split-socket, step-up type in both the old
and the new prostheses. (Fig. 4, Fig. 5)
The data on harnesses show a highly significant increase in the number of
figure-eight harnesses prescribed for below-elbow and above-elbow cases with the
new prostheses as compared with the old. The reasons for this increase are
related to the favorable attitude of the program toward this simple type of
harnessing, except for cases wherein heavy lifting was expected. Practically all
of the shoulder-disarticulation amputees had chest-strap harnesses on both the
old and the new prostheses.
Vinyon tape was specified in 96 percent of the prescriptions for new
prostheses, and cotton webbing or nylon or dacron tape were prescribed in the
remaining 4 percent. (Fig. 6, Fig. 7)
In the old prostheses, 83 percent of the harnesses were made of cotton
webbing, 8 percent were of leather, and the remaining 9 percent were made of
vinyon or nylon tape. The marked shift to the use of vinyon tape was due
primarily to the presumably superior characteristics attributed to vinyon with
respect to dimensional stability, washability, fraying, and resistance to
bacteria and fungi.
All of the prescriptions for new prostheses called for the use of the Bowden
cable in the control system. In the old prostheses, 58 percent utilized Bowden
cable; the remainder utilized nylon cord, leather, or steel cable without a
housing. The change to Bowden cable was effected to take advantage of its higher
efficiency in transmitting forces.
Four out of ten subjects said they had received treatment by some form of
exercise or other physical therapy prior to their entrance into the study. The
same proportion of the group indicated that their stumps had been bandaged to
bring about shrinkage.
In response to the question, Do you think these [preprosthetic] treatments
were helpful?, 79 percent replied in the affirmative and offered the following
reasons (in order of decreasing frequency): increased strength, increased range
of motion, helped stump shrinkage, reduced pain, improved function, reduced
During the course of the research studies, preprosthetic exercise or other
physical therapy was prescribed for 13 percent of the amputees treated. That
only a relatively small proportion of the subjects received
preprosthetic treatment is accounted for by the fact that most of the amputations occurred
quite some time before the amputees participated in the program. In most cases,
treatment consisted primarily of exercise to increase strength and range of
motion of the stump. Other physical-therapy measures, such as diathermy,
massage, and hydrotherapy, accounted for a relatively small proportion of
treatments. Almost all of the subjects indicated that treatment was received
daily. (Fig. 8, Fig. 9)
Seven percent of the amputees had their stumps bandaged to cause shrinkage.
About two thirds of this small group indicated that bandaging had been continued
over a period of 4 to 12 weeks; the remainder of the group said that bandaging
had been continued for more than 12 weeks.
Of those who did receive preprosthetic treatment, 88 percent considered the
treatments helpful. The reason given most frequently was that the treatments
increased strength and range of motion. About one out of five subjects mentioned
stump shrinkage as the chief beneficial effect.
With reference to arms worn prior to entrance into the program, the subjects
were asked: Was your arm checked for fit, comfort, and function before it was
delivered to youf Four out of five indicated that their prostheses had been
subjected to some form of initial checkout or evaluation, even though this was
not done on a formal basis. One third of this group said that the limbfitter had
made the check. Thirteen percent designated the physician as having made the
check, and 9 percent said the check was made at the hospital. The others did not
provide specific information as to who performed the checkout or evaluation.
A basic principle guiding operations in the Field Studies was that the
amputee would not be permitted to wear his new prosthesis or proceed to training
until initial checkout had been passed successfully. If deficiencies were
encountered that would interfere with wear or training, recommendations for
correction were made, and the amputee was scheduled to appear again so that
initial checkout could be completed.
Several factors serve to explain why a relatively large proportion of
amputees had to appear before the clinic two or more times in order to pass
initial checkout. One is that the checkout procedure proved to be highly
effective in directing attention to the necessary corrections and adjustments in
individual components and to the prosthesis as a whole. A second related to the
relatively high and rigid standards established by the checkout procedure. A
period of time was generally required before the prosthetic experience necessary
to meet these standards was gained. The relatively greater frequency with which
above-elbow and shoul-der-disarticulation amputees failed to pass initial
checkout on the first appearance, as compared to below-elbow amputees, was for
the most part due to difficulties in harnessing. In addition, the relatively small number of
shoulder disarticulations seen meant that it took correspondingly longer to
obtain substantial experience in their fitting and harnessing. (Fig. 10)
While a majority of prostheses passed initial checkout on the first
presentation, this does not mean that no deficiencies were found at initial
checkout in these cases. More often than not, a number of minor deficiencies
were found, which resulted in a "provisional pass" rather than a "pass." When a
provisional pass was given, recommendations were made for correction of the
minor deficiencies found. When the amputee reported for his first training
period, a check was made to see that the recommended changes had been
Among the below-elbow subjects, the most frequent deficiencies found at
initial checkout were in connection with sockets. With above-elbow amputees, the
deficiencies found most frequently were in connection with harnessing. The
fewest deficiencies were encountered with wrist units. The charts show the order
in which the various components ranked according to the number of deficiencies
The amputees taking part in the study were asked: Do you think it was worth
while that the new arm was checked for fit, comfort, and function before it was
delivered to you? Ninety-four percent of the replies were yes. The most common
reasons given for these replies were:
". . . to correct and prevent problems."
". . . provides a check on fit."
". . . provides a check on comfort."
". . . provides a check on prescription."
Some of the comments of those few who did not think it was a good procedure were:
". . . made no necessary changes to arm."
". . . am intelligent enough to decide for myself if it is comfortable."
". . . could be checked out at limbshop."
". . . had to wear it first to see if anything was wrong."
The data pertaining to previous training showed that 42 percent of the
amputees had received prosthetic training sometime prior to the beginning of the
study. Eighty-nine percent of this group expressed the opinion that this
training was helpful. Three fourths of the amputees who received no previous
training said they thought training would have been helpful, while the remaining
fourth thought it would have been of no use.
Data obtained from the clinical studies showed that 81 percent of the
subjects received training, that 14 percent received no training, and that owing to incomplete
records the training status was indefinite for the remaining 5 percent. Among
the amputees who received no training, the most common reasons offered were: the
amputee had worn a prosthesis before and previous training was considered
adequate; the amputee passed the prosthetic-use test without training; the
amputee declined training. (Fig. 11)
In response to a query concerning the value of prosthetic training, four out
of five amputees replied in the affirmative. Among the most frequent reasons
given for the affirmative answer were:
". . . training gives an idea of what can be done with the prosthesis."
". . . learned mechanical operation of components."
". . . expedited use of arm."
Of the group who did not believe that training was valuable, there were
proportionately twice as many below-elbow as above-elbow amputees. They offered
such comments as:
". . . using an arm is easy."
". . . training was not well organized."
". . . I would rather learn my own way."
". . . amputee was left on his own too much."
". . . training helped very little."
". . . training was not long enough "
In response to the question, Do you believe the training you were given in
the use of your new prosthesis could be improved?, 41 percent answered in the
affirmative. About one fourth of those who answered in the affirmative expressed
the opinion that there should be more training in activities of daily living. An
equal number thought that more time was needed. Among the group that expressed
the opinion that more time was needed there were more than three times as many
above-elbow amputees as there were below-elbow amputees.
Other suggestions for improvement of training were:
". . . there should be more enforced training."
". . . provide a training manual which would allow the amputee to practice at home."
". . . adapt training to occupational needs."
". . . there is not enough supervision of training."
The total training time for an individual amputee ranged from half an hour to
99 hours, but more than nine out of every ten amputees received less than 20
hours of training. Except for bilateral amputees, more than eight out of every
ten amputees received 10 hours or less of training. The average number of hours
of training for each amputee type is based on the great majority of amputees (94
percent) who required less than 20 hours of training. Of the small remaining
group of amputees (6 percent), one half received from 21 to 30 hours of
training; the other half received from 30 to 99 hours. It must, however, be
emphasized again that the larger part of this group had had previous prosthetic
experience. (Fig. 12)
The average length of individual training sessions for the amputees in the
clinical studies was one hour and forty minutes. There was no significant
difference in the figures for below-elbow, above-elbow,
shoulder-disarticulation, and bilateral amputees. For almost 50 percent of the
amputees, the length of the individual sessions was one hour.
In reply to the question, Did any difficulties arise in connection with the
operation or comfort of your new prosthesis during training or the initial
period of use?, 54 percent of the amputees replied in the affirmative. Among the
below-elbow subjects, the socket was the most frequent source of difficulties
relating to fit and comfort, while among the above-elbow group the harness
constituted the major source of trouble. With respect to function, operation of
terminal devices and the control system were the most troublesome. The control
system was the most common source of difficulty with respect to maintenance.
Prior to participation in the Field Studies, less than 30 percent of the
amputees had had their prostheses rechecked for fit, comfort, and function after
the period of initial wear or training. In accordance with the procedures
described in Section I, all prostheses in the Field Studies were subjected to
final checkout after the completion of training or the initial period of wear.
At this time not only was the prosthesis given a systematic and thorough
inspection and evaluation but, in addition, an appraisal was made of the
patient's ability to use the prosthesis, and a careful examination was made to
see if there were any medical or surgical problems that might interfere with
successful wear and use. Clinics considered that an amputee had "passed" final
checkout only when there were no further surgical, medical, or prosthetic
problems of any kind that required attention.
Sixty percent of the prostheses passed final checkout on first presentation,
26 percent passed on second presentation, and 14 percent required more than two
appearances to pass final checkout. This compares with 69 percent, 24 percent,
and 7 percent, respectively, for initial checkout.
The decrease in the number of prostheses that passed final checkout on first
presentation, as compared with initial checkout, was due chiefly to the results
of wear of the prosthesis, the emphasis on the amputee's ability to use the
prosthesis, the apparent need for additional training, and the need for
modifications which had been overlooked at the initial checkout or on which judgment had been
withheld until the effect of wear could be determined. The actual number of
deficiencies found at final checkout was, however, smaller by far than the
number at initial checkout. Among the below-elbow amputees, the total number of
deficiencies recorded at final checkout was only 339 as compared with 801 at
initial checkout. The corresponding figures for above-elbow amputees were 358 at
final checkout and 970 at initial checkout. These figures show clearly that the
prostheses were far better at final checkout than they were at initial checkout,
even though it took a little longer to get through the checkout procedure. (Fig. 13)
As was the case at initial checkout, the difficulties found most frequently
at final checkout were related to socket fit for the below-elbow amputee and to
harnessing for the above-elbow amputee. The fewest difficulties were encountered
in relation to wrist units. The order in which various components ranked
according to the number of deficiencies found is to be seen in the combined data
for initial and final checkout.
The effects of wear and use were to be seen in the continued difficulties
with fit and comfort of the below-elbow socket at final checkout and also in the relative increase in deficiencies encountered with terminal
devices. The more common deficiencies in the latter case were related to
malfunctions of hand or hook, staining of or damage to the cosmetic glove, and
excessive backlash with voluntary-closing devices.
At both checkouts, deficiencies of the elbow unit rank fairly high on the
list. Analysis indicates, however, that most of these difficulties were not with
the internal mechanism but rather with other factors such as adjustment of the
harness and control attachments that activate the elbow lock.
In response to the question, Do you think it was worth while that your arm
was rechecked for fit, comfort, and function after training and initial period
of wear?, 90 percent of the replies were in the affirmative. The most frequent
reason for this reply was that the recheck permitted problems to be corrected.
Typical comments were:
". . . gives an opportunity to correct problems after wear."
". . . experts can see difficulties better."
". . . it is important to find out if arm still functions properly."
". . . it provides a general check."
The amputees' experience in the field-studies program differed quite markedly
from their previous prosthetic experience with respect to prescription and final
checkout. Prior to their participation in the study, less than one out of five
had ever had a prosthesis that was prescribed by a clinic team, and less than
one third had had their previous prostheses subjected to a final comprehensive
checkout. (Fig. 14)
The differences with respect to preprosthetic treatment, initial checkout,
and training were less marked. Relatively fewer amputees received preprosthetic
treatment in connection with the new prostheses than was the case in connection
with the prostheses that were being worn at the beginning of the study. This, of
course, can be accounted for by the lessened need for these services with
increased prosthetic wear.
Although a substantial majority of the amputees said that their previous
prostheses had been subjected to some form of initial checkout or evaluation,
these had not been done on any formal or systematic basis and had in general not
involved the application of standards of acceptance.
Forty-two percent of the amputees who had worn a prosthesis prior to the
beginning of the study had received training in its use, although the nature or
extent of this training is not clear from the data. More than eight out of ten
subjects received training with the prostheses obtained in the research
Amputee opinion pertaining to the treatment process, as indicated by the data
gathered, was for the most part strongly in favor of the new procedures. Ninety-four percent of the amputees approved of the
team method of prescription. Eighty-eight percent of those who received
preprosthetic treatment said the treatments were helpful. Ninety-four percent
were of the opinion that initial checkout was worth while.
Four out of five amputees were of the opinion that the training they received
in the use of their prostheses was valuable. But 41 percent of the group thought
that training could be improved. The most frequent suggestions for improvement
were to increase the amount of training time and the amount of training in
meaningful activities of daily living.
The final checkout to which all of the prostheses in the research studies
were subjected was particularly comprehensive and designed to uncover any
medicosurgical, prosthetic, training, or other factors that might interfere with
successful wear and use. Nine out of ten amputees were of the opinion that this
procedure was worth while.
All in all, the treatment process inaugurated as part of the studies was
considered valuable and achieved a high degree of amputee acceptance.