A Therapeutic Program for Children with Limb Deformities Preservation of Rudimentary Appendices and Prosthetic Design

Selene Jaramillo, M.D. Hans R. Lehneis, C.P.O.


When a child is born with a deformed or missing limb, the event is so traumatic for his family and the physician that their first impulse is to try to hide the disability. The parents think of eosmesis before function, and frequently the child is fitted with a prosthesis without prior training or readiness for the artificial limb.

There is no question as to the importance of the psychological aspects of the problems confronting the child and his family. On the other hand, fitting a dysmelic child with a heavy and cumbersome prosthesis when he does not have the required muscle power, muscle bulk, or proper balance to manipulate it can be even more frustrating than not having a functional limb at all.

There is a tendency to blame the child's poor attention-span or negativeness on the prosthetist or to blame the family for poor cooperation, whereas the real problem frequently is the lack of pre-prosthetic training by means of a good exercise program.

Early Development Delayed

The infant born without upper extremities is delayed in the early developmental activities of head control, rolling, creeping, and sitting. In this initial period, the mother may be the best therapist. She should encourage the strengthening of neck and trunk flexors, extensors, and rotators and the use of the feet to play with the toys which hang on the child's crib. As the child grows, emphasis should be given to exercises for the shoulder-arm complex: elevation and depression, scapular abduction and adduction, and general chest expansion (respiratory exercises). When the child is able to sit. exercises for the lower extremities should be continued. He must be trained to use his feet at the maximum range in all directions. Trunk flexibility plays a very important role as do hip rotation, abduction, extension, and particularly flexion. He must be encouraged to explore his environment and devise ways of controlling it. His mouth and feet should replace the missing arms. Some clinicians discourage the use of the feet in order to force the child to be a good prosthesis user. However, they do not take into consideration the importance of tactile perception, which is so necessary for the child's mental, social, and emotional development.

Periodic X-rays Needed

While the youngster is developing his joint and spine flexibility, overstress of joint capsules or ligaments may occur. Periodic x-rays should be taken, therefore, to detect deformities (subluxations and/or dislocations, etc.). Amputees with humeral-neck or very short above-elbow-level stumps are frequently poor prosthesis users or do not use the prosthesis at all, largely because of the poor muscle power and limited range of motion of these stumps. This problem is aggravated by a limiting prosthetic shoulder cap. These stumps frequently need revision as the result of imbalance between muscle and bone growth (bony overgrowth). For these children, early exercises are fundamental to prevent deviations of the spine, keep a better bone/muscle balance, and maintain function. In these cases, the fabrication of the prosthesis should allow maximum scapular and humeral freedom, with provision made for the soft tissues to be pulled down with the stump sock.

Short Above-Knee Stumps. In the lower extremities, very short above-knee stumps present the greatest difficulties. Most of them have flexion-abduction contractures which, if not corrected, bring the pelvis into lordosis or lateral tilting. Exercises to stretch these muscles, reduce the deformities, increase the range of motion, and correct gait defects must be instituted early. As these children grow, the forward transference of the center of gravity becomes more difficult, and the patient tries to compensate by increased lumbar lordosis. In such cases, aligning the socket with appropriate initial flexion may minimize this problem and improve posture. If an adduction deformity is the main problem (as seen in coxa vara), a flexible spring-steel joint which provides a dynamic abduction force may improve the gait. Certainly, a continuous program of exercises throughout the prepubertal period is mandatory if the above-mentioned disabilities are to be reduced or avoided.

Bilateral Amelia. Children with bilateral lower-extremity amelia or short above-knee stumps must learn from infancy how to swing-through, supported on their hands. They must be able to lift the trunk in the vertical and horizontal positions and, if possible, to walk on their hands. This skill will enable them to take care of many of their daily living requirements independently, without going through the work of putting on the prosthesis frequently. If the child develops good strength in his upper limbs during the early years, the energy required for these activities will be readily available in later years. In our clinic, children have walked independently with crutches and bilateral Canadian hip-disarticulation prostheses at the ages of 2 1/2 to 3 years.

Balance Training

For children with unilateral dysmelia, balance training is essential. We can expect a child to walk better with a prosthesis if he is able to stand unassisted on the sound leg, to bend and rotate his trunk, and to flex his sound knee without his prosthesis. It is true that most of these children require only minimal training, but it is important that they learn very early to perform correctly and to avoid developing defects in gait or upper-extremity function which are difficult to correct. In this exercise program, the family and the school teachers must be part of the team. Like any other child the amputee should be encouraged to participate in sports and games as early as possible.

The Problem of Scoliosis

Scoliosis is a frequent problem in children with limb deformities, and not infrequently spinal defects are found, such as sacralization of lumbar vertabrae, hemivertabrae, rudimentary vertabral bodies, etc. Therefore, x-rays of the spine should be routinely taken for all such children. The exercise program for the scoliotic child must be well-organized and controlled in order to prevent functional scoliosis from becoming structural. It is frequently necessary to provide these children with specialized bracing or to undertake surgical procedures to limit the scoliotic process. However, the limitations imposed by spinal fusion must be carefully considered in children with bilateral upper-extremity amelia or those with very short stumps, where trunk flexibility is so necessary for foot use.

Preservation of Rudimentary Appendices and Prosthetic Design

Important as the exercise program is, the preservation of rudimentary appendices or digits is essential, even though in the first years of life they do not have any function. By appropriate training, they may later play a useful role in the operation of the prosthesis or in the child's activities of daily living. It has been customary in the past to remove these appendices early in order to avoid the psychological trauma of removal when the child is older or to make possible the fitting of a prosthesis with improved cosmesis. However, as the patients presented in this paper will demonstrate, these digits may eventually develop power and become functional. These digits provide tactile sensations which are so important in the child's life; and which can never be replaced by a prosthesis.

Case No. 1

This 13-year-old female has been seen in our prosthetic clinic since she was 1 1/2 years of age. She has a diagnosis of congenital absence of the left forearm with one digit only on this extremity. She received her first above-elbow prosthesis at the age of 1 1/2 years. It consisted of a closed-end socket incorporating the digit, a passive elbow, and a wafer-hook. As she became older, an elbow lock was added. For the first two years of training, the single linger seemed to be of no functional value since no motor power was evident. It was also a constant source of irritation and discomfort when the prosthesis was worn. Frequent socket modifications were necessary to improve comfort and to allow room for growth of the finger. This problem was aggravated by the fact that the patient refused to have an opening made in the prosthetic socket to allow protrusion of the finger. As the prosthetic problems grew, the psychological status of the child and family deteriorated. The patient refused to wear the prosthesis for long intervals. Removal of the finger was suggested but was rejected by the family. The child became progressively more interested in moving the finger and finally it developed increased motor power, good mobility, and function.

Her present prosthesis was devised to utilize this mobility for elbow-lock control. For this purpose a stump-activated elbow lock, modified by a lever which ran from the lock to a semicircular receptacle for the finger, was used. This method of control not only simplified the harness system but also permitted a less bulky socket configuration. The cross-sectional geometry of the socket resulting from exposure of the digit permitted increased range and control of internal and external humeral rotation. Thus, the need for a high proximal socket lit was eliminated and cosmesis of the shoulder area improved. Aside from the obvious advantage of utilizing the finger for elbow-lock control, the exceptionally great mobility of the linger, almost representing a universal joint, permits its use for other purposes even when the prosthesis is worn, particularly when sensibility is needed (Fig. 1 and Fig. 2 ).

As a secondary problem, a progressive shortening of the child's ipsilateral lower extremity was noted. A tibial epiphysiodesis on the contralateral side was performed six months ago to equalize growth. During the patient's period of hospitalization, she gained considerable weight. We were pleased to note that despite this increase the upper-extremity socket needed no modifications. In the earlier fitting the anterior of the socket had been provided with a longitudinal split to facilitate donning of the prosthesis, and this split permitted accommodation for the change in stump size.

Case No. 2

This two-year-old female was born with bilateral femoral aplasia, a left fibular hemimelia with a severe valgus foot, a right elbow disarticulation, and a left transverse hemimelia with one finger on the stump. As in the first case, this finger was not functional for the first 15 months, although it was noted that the baby used it for "thumb" sucking. This fact alone made us decide against amputation of the digit, even though it appeared to have no other functional use. Fortunately, in recent months she has developed good power and mobility in the finger which aids her in feeding and holding certain objects. A socket similar to the one described in Case #1 (except that no elbow lock was provided) was fitted in order to leave the finger free for better development and to permit its continuous use while the prosthesis was worn. She was fitted with bilateral long-leg braces with a pelvic band at the age of one year to stretch her hip flexors and facilitate standing and ambulation. Now both femurs are in good alignment, and she is starting to walk with the braces as well as without them. Without her prostheses she simply uses the single digit on her left slump to steady herself by touching it to tables and other objects as she moves about. Prior to the bracing, the valgus foot deformity was corrected by weekly casting.

Case No. 3

This five-year-old female was born with absence of the left upper extremity below the elbow. A remnant of the ulna was attached to the humerus, and soft-tissue rays with a few centers of ossification simulated a hand (Fig. 3 ). In previous prosthetic fittings, this ulnar remnant and the soft-tissue rays had always caused discomfort and resulted in a bulky appearance. Because of the excessive stump length, a prosthesis with an internal elbow lock could not be provided. Although external elbow hinges were considered, the child was fitted eventually with a "banana"-type prosthesis at 18 months of age (Fig. 5 ).

A new prosthesis presently being fitted has an open socket to expose the distal portion of the stump. Elimination of socket material distally permits the external elbow-lock hinges to be fitted closer to the stump, and results in a diminished diameter between the joints. This decrease considerably reduces the bulkiness which, with a conventional socket, would have been quite severe. Even though there is no mobility or power in the rudimentary ulna and hand, design of the prosthetic socket to expose this area reduces fitting problems, eliminates a constant source of discomfort, and accommodates growth without frequent socket changes or adjustments. An additional benefit derived from an open socket is use of the sensibility of the distal stump end. As in this case, the stump may also be used in holding or manipulating objects on a table. This is done when the elbow is fully flexed, thus exposing the distal end of the stump. In addition to the sensory feedback provided, exposure of the stump provides better friction when holding objects as compared to the hard socket material. The described prosthetic solution has been well accepted by the parents and the child.

Case No. 4

This is an eight-year-old female with congenital bilateral deficiencies through the upper portions of the thighs. The child had only small fragments of both femurs: one toe was present on the right side (Fig. 5 ). She was fitted at the age of 1 1/2 years with bilateral Canadian-type hip-disarticulation prostheses. By the age of 2 1/2 years, she was completely independent in swing-through gait with these prostheses and crutches. A window was made in the socket to accommodate the toe. As the patient became older, she experienced discomfort at the point of exit of the toe, but the main complaint was its interference with clothing which caused a poor appearance. Both the parents and the child were aware of the problem, and they requested surgery because the toe was not functional. Without her prosthesis, the patient was checked in locomotion, sitting, and balance: and it was believed that this toe was not being used at all. The digit was surgically removed, and it was only a few days after surgery that she realized that she needed her toe for toileting activities. She had used the toe as an anchor to hold herself on the toilet bowl, and now-found it necessary to use a hand for this purpose.

Conclusions

We have presented three patients whose rudimentary appendices (with appropriate modifications of prosthetic design) have been determining factors in the achievement of improved function. A fourth ease illustrates the loss of an important function when a presumably useless digit was removed. We believe that a decision to surgically remove these appendices should never be made precipitously, particularly in the first years of life when their power or mobility is either nonexistent or nonapparent. We have also emphasized the importance of early and continuous exercises for the best prosthetic performance and for the correction or prevention of deformities, particularly in the most severe cases.

Obviously, in the eases described and in similar conditions, prosthetic design must be highly individualized. This requirement, of course, demands a great deal of imagination, time, and discussion on the part of all members of the clinic team and, last but not least, requires the total cooperation of the patient and his or her parents. This effort, however, is well worthwhile in the resulting improvement in prosthetic function and comfort. An open socket tends to increase the life span of a prosthesis by permitting nearly unrestricted growth of rudimentary appendices, and thus has important economic as well as functional advantages.

Selene Jaramillo, M.D. and Hans R. Lehneis, C.P.O. are associated with the Institute of Rehabilitation Medicine New York University Medical Center