Chestley L. Yelton, M. D.
Much research is now being done to explain the various deformities, deficiencies, reduplications and redundancies which may be found in the human infant at birth.
It is not the purpose of this article to discuss the experimental and clinical evidence concerning the causes of congenital developmental anomalies. Suffice to say that at least one type of congenital malformation in human beings, mongolism, can now be definitely ascribed to a genetic mechanism. On the other hand, the recent thalidomide episode indicates that an external causative agent may also be the responsible factor. In this case, the type and extent of damage appears closely related to the stage of embryonic development at which the teratogenic agent is effective.
One group of congenital defects which has been of particular interest to the participating clinic chiefs, as well as others, is in the area of femoral deficiencies. At meetings of the child amputee research group, both Dr. George T. Aitken, of Grand Rapids, Michigan, and Dr. Ernest M. Burgess, of Seattle, Washington, have discussed various aspects of this condition: types and surgical and prosthetic management.
Dr. Richard E. King, of Atlanta, Georgia, in an earlier article in the Inter-Clinic Information Bulletin (Volume I, Number 2, November, 1961), proposed to place infantile and congenital coxa vara in the same group and include proximal femoral focal deficiencies. An excellent recent article by Amstutz and Wilson1 identified three distinct groups: congenital short femur with coxa vara, congenital bowed femur with coxa vara and congenital coxa vara.
Despite the manifest interest, one finds in searching the literature that reports of congenital defects of the femur are rare. In Birmingham, we have not encountered sufficient cases to develop a comprehensive series. We have, however, followed several patients with femoral deficiencies over a period of years. The characteristics of their deficiencies and the changes which occur with growth are intriguing and, at times, puzzling. We are therefore presenting several selected cases in the hope that they will be equally interesting to our colleagues and perhaps contribute to the sum total of knowledge concerning the condition. Comments from readers of the Inter-Clinic Information Bulletin would be appreciated.
Case 1: Fig. 1A is that of a year-old infant with an apparent absence of the left femur. Fig. 1B depicts the deficiency at four years of age and reveals a bone mass which has appeared at the upper end of the tibia. Fig. 1C shows the deficiency at 10 years of age. Note the protuberance on the medial aspect of the upper end of the tibia which resembles a lesser trochanter.
Case 2: Fig. 2 is that of a male child. Of interest here is the shortened fibula with its proximal end situated much more distally than is normal and revealing a definite epiphyseal line. Note the spherical bone at the acetabulum - is this the femoral head? No patella is evident.
Case 3: Fig. 3A is that of a six-months-old male with apparent absence of the femur, bilateral. There is a suggestion of rudimentary ossification of the left femoral condyle (see arrow). Fig. 3B depicts the same child at six years of age. A large ossification center for the femoral condyle is present, bilaterally. This case is active and we hope to keep him under observation and X-ray him at intervals to follow further femoral development.
Case 4: Fig. 4 . A male with only the femoral condyle and adjacent spherical bone articulating with the acetabulum area, bilateral.
Case 5: Fig. 5 . A female, age 16 years, similar to Case A but also having a bilateral paraxial fibula hemimelia. Bilateral congenital absence of femur and fibula is extremely rare. What are the bony masses above the acetabuli?
Chestley Yelton is Professor of Orthopaedic Surgery, University of Alabama Medical College and Chief, Birmingham Child Amputee Clinic Birmingham, Alabama
1. Amstutz, H.C, and Wilson, P.D., "Dysgenesis of the Proximal Femur (coxa vara) and its Surgical Management", Journal of Bone and Joint Surgery, AA-A, pp. 1-2A, January, 1962. (An abstract of this article appears on Page 6.)