Children With Amputations

Elizabeth J4 Davies, M.A. Barbara R. Friz, M.S. Frank W. Clippinger, Jr., M.D.


Descriptive record forms on amputees being fitted with prostheses were completed by 44 prosthetic facilities representing 30 states during a period of approximately two years, ending June 30, 1967. A total of 8,323 amputees with 8,698 amputations were included in the study.

Entitled "The Facility Case Record Study," this project was initiated by the Conference of Prosthetists of the American Orthotic and Prosthetic Association to encourage the development of a system of permanent, inclusive record-keeping on amputee patients. Duplicate copies were submitted to the Committee on Prosthetic-Orthotic Education,+ National Research Council, so that data of special significance could be extracted, coded, and analyzed.

This paper presents data of interest relating to the child amputee.

Parameters

Children receiving their first prosthesis, or amputations being fitted for the first time, were considered as "new" cases. Children receiving replacement prostheses, or amputations being fitted with replacement prostheses, were considered to be "old" cases.

For the purpose of this study, individuals up to and including 20 years of age were classified as children and were grouped in the following age categories:

  1. 5 years and under

  2. 6 to 10 years

  3. 11 to 17 years

  4. 18 through 20 years

These particular groups were selected to provide categories representing the very young child, the child who had not yet reached the age of rapid growth, the child during the years he was growing rapidly, and the late teen-ager.

Ages reported throughout the study refer to the ages of the amputee at the time of fitting. In instances where new amputees are analyzed in relation to age, it should be borne in mind that actual age at time of amputation would, to a variable degree, be lower than that which is recorded, depending upon the time lapse between amputation and delivery of the prosthesis .

Causes of amputations were considered in four categories: congenital, tumor, trauma, and disease. Cases of infection, gangrene, or osteomyelitis resulting from trauma were classified under "trauma." Any cases of trauma associated with vascular disease were classified under "disease."

Nine hundred sixty eight unilateral, 78 bilateral, three double, and two triple amputees comprised the sample of 1,051 children with 1,136 amputations studied. Of these 1,136 amputations 471 were "new" and 665 were "old." Causes of amputation were reported for 1,036 children having 1,118 amputations.

Data in this report relate to age, sex, level, and cause of amputation(s), reamputation(s) for bony overgrowth, prosthetic components prescribed, months to delivery of prostheses for "new" cases, age of replaced prostheses by level, reasons for replacement, and sources of payment for prostheses.

Age, Sex, Site of Amputation

Of the 1,136 amputations, 740 occurred in males and 396 in females, a ratio of almost 2:1. There were 775 amputations of the lower extremity and 361 of the upper extremity (Table 1 ).

In the lower extremity, the left side was involved 380 times and the right 395 times, the difference being without statistical significance. The left upper extremity was involved 194 times as compared to 167 times for the right, the difference being statistically significant at the 1-per-cent level of confidence.

The most frequent level of amputation in the lower extremity was below-knee, accounting for 54 per cent of all lower-extremity amputations. In the upper extremity, below-elbow was the most frequent level of amputation, accounting for 61 per cent of all upper-extremity amputations (Table 2 ),

Eighty-three amputees, 50 males and 33 females, had two or more amputated extremities. The occurrence of multiple amputations is recorded in Table 3 .

Causes of Amputation

In 1,118 amputations where the causes were known, congenital amputations accounted for 52 per cent, trauma for 35 per cent, tumor for 9 per cent, and disease for 4 per cent of the cases (Table 4 ). These percentages refer to all amputations, both "old" and "new," being fitted with prostheses. There appeared to be no significant difference between the number of males and females amputated for tumor or disease; however, males outnumbered females almost 5:1 in incidence of amputations for trauma and 1.3:1 in incidence of congenital anomalies.

The analysis of the data for both "new" and "old" amputations at the time of prosthetic fitting revealed some interesting comparisons (Table 5 ). Of the 466 "new" amputations where causes were known, trauma accounted for 42 per cent of the amputations, congenital anomalies for 37 per cent, tumor for 17 per cent, and disease for 4 per cent. In contrast to this distribution, the 652 "old" amputations with known causes fell into the following categories: 63 per cent were of congenital origin, 29 per cent were caused by trauma, 4 per cent were caused by tumor, and 4 per cent by disease.

The larger numbers of children with "old" congenital deficiencies as compared to "new" apparently reflect the fact that the majority of congenital amputees receive their first prosthesis before the age of 5 years, and so would be expected to receive several replacement prostheses before reaching age 20. Amputations resulting from trauma did not peak until after the age of 10 years, so fewer replacement prostheses would be required by the age of 20. Actually, the number of trauma cases being fitted for the first time was almost equal to the number being fitted with replacement prostheses. The number of "new" tumor cases was approximately triple that of the "old" tumor cases being fitted. As in the trauma cases, this finding may indicate a higher age at the time of first fitting. It may also be that, because of reduced life expeotancy, some patients who lose a limb because of tumor do not require replacement prostheses.

A further analysis of the data for "new" amputations considered causes in relation to the age, sex, and site of amputation (Table 6 ).

Congenital - "New" Amputations

Of the 171 "new" congenital amputations, 99 occurred in the upper extremity as opposed to 72 in the lower. Males accounted for more congenital amputations than females: 94 to 77, with 61 per cent fitted prior to the sixth birthday, and 25 per cent fitted after the eleventh birthday.

Tumor - "New" Amputations

Amputations of the upper extremity were few with the incidence essentially constant in relation to age throughout childhood. In contrast, amputations of the lower extremity showed a sharp increase in incidence from the age of 11 years on. Eighty-four per cent of amputations for tumor occurred in children between the ages of 11 and 20; 89 per cent of all new tumor cases involved the lower extremity.

In comparing the incidence of tumor in children with that of adults, it was found that tumor occurred more frequently in the second decade than in any other.

Trauma - "New" Amputations

Of the 198 "new" trauma amputations, 121 occurred in the lower extremity, 77 in the upper. There were 173 amputations in males, accounting for 87 per cent of the total number in this category. The incidence of trauma rose sharply after the age of 11 years, accounting for 77 per cent of the cases.

Table 7 indicates the age and sex of "new" patients as they relate to types of trauma. Automobiles accounted for 26 per cent of all accidents where the causes of trauma were known. Excluding causes listed under "other," the leading cause of traumatic amputations in males was car accidents (24 per cent), followed by industrial accidents (11 per cent), and train and farm accidents (10 per cent each). Interestingly, the number of accidents from lawn mowers was approximately equal to the number of car accidents for boys under 11 years of age. However, the number of cases involved was small.

Car accidents accounted for 36 per cent of the 25 known causes of traumatic amputations in females.

Disease - "New" Amputations

Disease appears to be a minor cause of amputations in children, being so designated in only four per cent of the cases in this study.

Reamputations for Bony Overgrowth

Only seven child amputees were reported as having reamputations for bony overgrowth. This information may not present a true picture, since "revisions" were not coded as reamputations, and it is possible that some problems of bony overgrowth fell into this category. Of the seven, tibial overgrowth was cited in four cases, fibular overgrowth in two, and the bone involved was not specified in one case. Four of the children were wearing patellar-tendon-bearing (PTB) sockets; three were wearing hard, open-end sockets.

Comparisons with Other Studies

Some comparisons can be made between this study, a normative survey sample obtained by Kay and Fishman from 1959 to 19631, and a patient census at child amputee clinics taken by Munson and Dolan in 19672 (Table 8 ).

The children (1,036) in our study with known causes of amputation were used for the comparisons. It should be noted, however, that there are some basic differences in the three populations:

  1. The Kay-Fishman and Munson-Dolan data related to children treated in organized child amputee clinics where one would be apt to find more complicated cases, such as children with congenital limb deficiencies. On the other hand, the data for the present study derived from prosthetic facilities where patients may be referred from an amputee clinic or in uncomplicated cases may be referred directly by a physician.

  2. The cut-off age limit in the Kay-Fishman study was 15 years,while in the Munson-Dolan and in the present study it was 21 years.

  3. While the Kay-Fishman and the present study involve slightly more than 1,000 children, almost 4,000 subjects were included in the Munson-Dolan study.

The present study shows a higher percentage of males (65 per cent) than did either that of Kay and Fishman (56 per cent) or Munson and Dolan (57 per cent). The ratio of congenital to Unilateral Amputations, Sex, and Cause acquired amputations was lower in the present study than in either of the other studies, being almost 1:1, whereas the Kay-Fishman survey showed a ratio of 2.6:1 and the Munson-Dolan 2:1. Both the Kay-Fishman and Munson-Dolan studies showed a greater number of upper-extremity than lower-extremity unilateral amputees. In our study, the ration of upper- to lower-extremity amputations among unilateral amputees was approximately 1:2; in the Kay-Fishman survey, approximately 2:1; and in the Munson-Dolan census, 1.2:1.

Thus, the present study is characterized by relatively higher ratios of males to females, acquired to congenital, and unilateral lower- to upper-extremity amputations. In part, these differences may be attributed to the influence of the older male children in the sample with acquired unilateral lower-extremity amputations. For example, 83 per cent of the children in the Munson-Dolan study were "old" cases compared to 58 per cent "old" cases in the present survey. If we consider the "old" cases only in our study, the ratio of congenital to acquired amputations becomes 1.7:1, which more closely approximates the 2:1 ratio of the census study. However, these factors do not adequately explain the low ratio of unilateral upper- to lower-extremity amputations in the present study. The reason for this situation is not readily apparent.

In a further comparison between our study and that of Kay-Fishman, the type of amputation in relation to sex and cause may be analyzed (Table 9 ). Among congenital amputees with unilateral involvement, where the proportion of males to females was almost equal in the Kay-Fishman survey, our study showed a slightly higher ratio of males to females, 1.3:1. In the Kay-Fishman study, the upper extremity of unilateral congenital amputees was involved almost three times as frequently as the lower, whereas in our study the lower: extremity was involved 1.2 times as frequently as the upper.

These data underscore the point made above, that for some reason a lower proportion of children with unilateral congenital upper-extremity deficiencies was included in the present sample.

Among children with unilateral acquired amputations, Kay and Fishman found that upper- and lower-extremity losses were approximately equal. In our study, lower-extremity losses exceeded upper by more than 3:1. Kay and Fishman also found that males outnumbered females approximately 2:1, while our study indicated that males outnumbered females approximately 3:1. These differences may relate in part to the higher age groups included in our study. However, the high proportion of unilateral lower-extremity losses is still noteworthy.

In a comparative examination of acquired amputations, liberty was taken in separating the tumor category from other categories included under "disease" in the Kay-Fishman survey (Table 10 ). In the survey, two-thirds of the 285 children with acquired amputations were amputated because of trauma. Of the 515 children with acquired amputations in our study, 72 per cent were amputated because of trauma.

Both our study and the Kay-Fishman study found the number of tumor cases was equal or almost equal for boys and girls. Of interest is the fact that our study showed that the lower-extremity involvement was nine and one-half times more frequent than the upper, as opposed to the findings of Kay and Fishman that the lower extremity was involved only slightly more than twice as frequently.

Prosthetic Components

Prescriptions for certain prosthetic components for children were compared with prescriptions for adults (Table 11 and Table 12 ).

The SACH foot was used much more frequently for children than for adults. For above-knee amputations, it was used in 81 per cent of fittings as opposed to 53 per cent, and for below-knee amputations, 95 per cent as opposed to 70 per cent.

The knee cuff alone was the choice of suspension for patellar-tendon-bearing sockets, accounting for 64 per cent of the suspension mechanisms for children, approximately the same as the 61 per cent used for adults. Closer study of the data reveals that for children under five years of age only 34 per cent of prescriptions for suspension of PTB sockets was for the knee cuff alone. However, the percentage rapidly increased until it reached 73 per cent for children in the 11 to 17 age group and 74 percent for children in the 18 to 20 year old category, which is considerably higher than the adult average.

Suction alone and suction in combination with other means of suspension for above-knee amputations was used almost twice as frequently in children as in adults (49 per cent versus 27 per cent). Adults depended upon pelvic belts twice as frequently as children.

On below-elbow amputations, the double wall socket was used to a greater extent by adults (81 per cent) than children (70 per cent). The preflexed socket was prescribed over three times as frequently for children (15 per cent) as for adults (5 per cent). At the above-elbow level, children and adults used the double-wall socket with almost equal frequency.

Months to Delivery

"New" amputees in the 11 to 20 year old age group were studied to determine the number of months from birth or date of amputation to delivery of their first prosthesis. Children with amputations for tumor were considered as a group and compared with children with amputations from all other causes. The median number of months to delivery of the prosthesis for children with tumor was four months, as opposed to five months for children with amputations for other causes.

The number of months from birth to delivery of the prosthesis was determined for congenital amputees who did not have surgery, and from date of surgery to delivery of prosthesis for those who did. No attempt was made to study this particular area by age of amputee, so some adults were included in the reported data; however, the vast majority were children. The median number of months to delivery of the prosthesis for congenital amputees following surgery was three months and for congenital amputees without surgery, 31-36 months. The months to delivery in the latter instance ranged from six months to 99 months or more.

Age of Replaced Prosthesis

The average age of the child's prosthesis at time of replacement was 2.5 years. The average age of adult prostheses was 6.7 years. In considering prostheses for above- and below-elbow, and above- and below-knee amputations, above-elbow prostheses appeared to have the longest life for both children and adults; below-knee prostheses had the shortest life. This replacement rate presumably reflects the extent of use of the devices (Table 13 ). The age of the replaced prosthesis was correlated with the age of the child and level of amputation (Chart A ). It is interesting to note that, as the age of the child increased, the wear-life of the prosthesis for the four levels analyzed also increased, with the exception of the be low-elbow prosthesis, the life of which remained constant at 2.8 years from ages 6-20. The average life of prostheses for the four levels was 1.7 years at the 0-5 year age level; 2.2 years at the 6-10 year level; 2.5 years at the 11-17 year level; and 3.6 years from 18-20 years of age.

Reason for Replacement

As would be expected, the main reason for replacement of prostheses in children where causes of amputation were known was that the prostheses had been outgrown. "Outgrown" was mentioned as the sole cause of replacement in 46.7 per cent of the cases. "Outgrown" and "worn out" were given as reasons, either singly or jointly, in 81.5 per cent of the cases.

An analysis by age group (Chart B ) reveals that "outgrown" was listed as the sole reason for prosthetic replacement in 62 per cent of the amputations at the 0-5 age group, and that this reason declined steadily to a low of 31 per cent by the ages of 18-20 years. Conversely, "worn out" increased steadily as a reason for replacement from a low of one per cent for the 0-5 age group to 26 per cent for the 18-20 age group. The percentages listed do not reflect those instances where "outgrown" and "worn out" were listed jointly as reasons for replacement.

Source of Payment

The Children's Bureau supported purchases of prostheses for 46 per cent of the children. Welfare provided financial support for 18 per cent, and the family paid for 17 per cent of the prostheses. Other sources of payment are listed in Table 14 .

Summary

A sample of 1,051 child amputees ranging in age from less than six months to 20 years, with 1,136 amputations, was studied. The data analyzed included the age and sex of the amputee, the level and cause of amputation, re-amputations due to bony overgrowth, comparison between selected prosthetic components prescribed for children and for adults, comparisons of the ages of replaced prostheses for children and for adults, reasons for replacement of prostheses, and sources of payment.

The findings in this study were compared with the Kay-Fishman Normative Survey and the Patient Census at Child Amputee Clinics by Munson and Dolan. The sample on which the present report is based was characterized by relatively higher ratios of male to female, acquired to congenital, and unilateral lower- to upper-extremity amputations than the two other studies.

The causes of amputation were divided into four categories: congenital, tumor, trauma, and disease. Causes were correlated with age, sex, and extremity for "new" amputees, i.e., amputees being fitted for their first prosthesis.

Trauma accounted for 42 per cent of the amputations in "new" amputees, with 77 per cent occurring after the age of 11 years. In the category of "new" traumatic amputations, males outnumbered females 7:1.

Congenital anomalies were responsible for 37 per cent of "new" amputations. Involvement of the upper extremity was greater than that of the lower, 99 to 72; amputations in males outnumbered those in females 94 to 77. Only 61 per cent of amputations in congenital amputees were fitted before the child was six years of age.

Tumor causes 17 per cent of "new" amputations. Eighty-four per cent of these amputations occurred after the eleventh birthday, and 89 per cent were amputations of the lower extremity.

Disease was a minor cause of amputation in children.

In analyzing the prescription for selected components for the lower-extremity prosthesis, the SACH foot for both above-knee and below-knee amputations, the knee-cuff for PTB suspension, and suction for above-knee socket suspension were all prescribed more frequently for the child than the adult. For the upper extremity, the double-wall socket was prescribed less frequently for the child than for the adult but the reverse was true in the prescription of preflexed sockets.

The median number of months from date of birth or amputation to delivery of prostheses for "new" cases in the 11 to 20 year-old category was four months for children with tumor and five months for all other cases considered together.

The average age of a replaced prosthesis for the child was 2.5 years; for the adult, 6.7 years. The below-knee prosthesis had the shortest life, the above-elbow the longest.

The Children's Bureau was the source of payment for 46 per cent of all prostheses, exceeding any other single source by a wide margin.

The Committee on Prosthetic-Orthotic Education is supported by the Social and Rehabilitation Service, Department of Health, Education, and Welfare, and by the Prosthetic and Sensory Aids Service of the Veterans Administration.

Elizabeth J4 Davies, M.A. and Barbara R. Friz, M.S. are Professional Assistant and Executive Secretary, respectively, Committee on Prosthetic-Orthotic Education, Division of Medical Sciences, National Academy of Sciences, National Research Council, Washington, D.C.

Frank W. Clippinger, Jr., M.D. is the Professor of Orthopaedic Surgery, Duke University; Chairman,Subcommittee

References:
1. Kay, Hector W., and Sidney Fishman: 1018 Children with Skeletal Limb Deficiencies, New York University Post-Graduate Medical School, Prosthetics and Orthotics, March 1967. 
2. Munson, Nancy K., and Clyde M.E. Dolan: Patient Census at Child Amputee Clinics - 1967, New York University Post-Graduate Medical School, Prosthetics and Orthotics, May 1968.