Prosthetic Fitting Following Amputation For Bone Tumor: A Preliminary Report

George T. Aitken, M.D.


One of the controversial problems in the management of the Juvenile amputee is to determine whether or not a fitting should be attempted in those cases where the extremity has been removed because of a malignant tumor.

The Area Child Amputee Center has treated 47 amputees where the etiology of amputation was a primary bone tumor. The majority of these cases were amputated elsewhere and referred to us for a decision concerning prosthetic fitting. In all instances an effort was made to acquire a duplicate slide of the pathological specimen. When such slides were obtainable, they were checked with other pathologists who confirmed the malignancy of the lesion. Occasionally, a difference arose in the designation of the type of tumor, but in no case was there disagreement concerning its malignancy. This article presents preliminary findings from our data on these patients with respect to wear of prostheses. A more comprehensive analysis and report will be presented at a later date.

The distribution of the 47 cases comprising our sample was 22 males and 25 females. Forty-one lower extremity and six upper extremity amputations had been performed, a ratio of almost 7:1. The types of lower extremity amputations were: one be low-knee, 31 above-knee, seven hip-disarticulations, and two hemi-pelvectomies. The upper extremity distribution was: one below-elbow, two above-elbow, two shoulder-disarticulations, and one forequarter.

Four Groups

Twenty-two of these patients are known to be deceased, seven were lost to follow-up and 18 are still alive. In investigating whether these patients were suitable subjects for prostheses, the most meaningful determination to be made from our data was the known period of prosthetic wear. To obtain this statistic, we arbitrarily categorized our patients into four groups:

1. Those who were never fitted:

4

2. Those who died while under care:

17

3. Those lost to care but alive at the time they were lost:

14

4. Those still under care:

11

One patient of the original 47 is not included in this breakdown. Although he was fitted and is known to have died, we have no reliable information concerning the date of his death or the length of time he wore the artificial limb.

In Group 1, those who were never fitted, three of the four patients have expired and the outcome in the remaining case is unknown.

Group 2, those who died while under care, involved 17 patients, all of whom were fitted with prostheses. The shortest period of wear in this group was two months and the longest was four years. Bight children wore their prostheses for at least one year, the average period of survival being 1.2 years.

Group 3, those lost to follow-up, contained 14 cases. Some of these were lost because they became 21 years of age and could no longer be treated in our clinic. Others simply disappeared from our service for unknown reasons. The longest wear period in this group was nine years and nine months, the shortest was two months, and the average was 3.2 years, with eleven of the children obtaining at least one year's use of their prostheses. These figures, of course, do not give a complete picture in that some of those lost to follow-up are still presumably alive. We have not been able to locate these patients and thus have no idea of the full length of time they have worn their prostheses.

In Group 4, those patients actively under care at the present time, the longest period of wear among the 11 subjects is seven years and eleven months. The shortest wear period is three months and the average is 2.8 years. This group also includes four long-term wearers who have worn their prostheses for periods of six years and one month, five years and six months, three years and ten months, and two years and ten months. Three other patients have worn their limbs longer than one year. Thus a total of eight of the eleven subjects in this category have obtained at least one year of use from the prescribed prosthesis.

Summary

In this initial analysis of our data we have not attempted to relate the character of the tumor or its location to a prognosis for prosthetic fitting. Suffice to emphasize at this time the overall indication that regardless of the type or location of the tumor amputations in children for a malignancy are not an "a priori" contraindication to fitting. In the group who died while still under care, the average period of wear was 1.2 years. In those lost to follow-up the average was 3.2 years, and in those still under care the average is 2.8 years. Moreover, of the 42 children on whom meaningful (although in some instances incomplete) data is available, 27 or 63 per cent (almost two out of three) lived at least a year following the fitting of a prosthesis. Some, of course, survived as long as five, seven and nine years following fitting.

These figures appear to substantiate the philosophy that children who lose an extremity because of a malignancy are entitled to prosthetic fitting in spite of an uncertain prognosis. At the present time the science of medicine cannot provide us with a sufficiently accurate prognosis of longevity on which we can make judgments concerning prosthetic fitting. It is recommended therefore that patients amputated for primary bone tumors who have a stump that is satisfactory for fitting and who have negative X-rays of the chest and of the stump should be fitted. Adherence to such a philosophy would provide many children with an extended period of active, useful function. Since the ratio of lower extremity to upper extremity cases is approximately 7:1, the provision of some mechanism in order that this large group may ambulate without the use of crutches seems almost mandatory, particularly when viewed against the background of our experience.

George Aitken is Medical Co-Director, The Area Child Amputee Center Michigan Crippled Children Commission, Grand Rapids, Michigan