Applicability Of The Patellar Tendon Bearing Prosthesis To Skeletally Immature Amputees

Claude N. Lambert, M.D.


This article presents the salient points of a verbal report given by Dr. Lambert at the Conference of Child Amputee Clinic Chiefs on January 24, 1964 at Chicago.

Following the apparently successful application of the Patellar Tendon Bearing Prosthesis to adult patients with below-knee amputations, a number of child amputee centers, including the University of Illinois, began fitting this type prosthesis to children. However, in some quarters reservations have been expressed concerning the possibly deleterious effects which may accrue with this prosthesis when applied to skeletally immature patients. It is postulated that the omission of supporting side hinges and thigh corsets in the basic PTB Prosthesis, with resulting increased stress on the bony and ligamentous structures of the amputated limb might have undesirable results. In view of this possibility, therefore, we undertook a study of children fitted with the PTB Prosthesis through the University of Illinois Amputee Clinic. This report presents our experience to date.

Twenty-Four Patients

Since April, 1960, 40 children have been fitted with patellar tendon bearing type prostheses through our amputee clinic. Knee hinges and thigh corsets were added to the prostheses of 16 of the 40 children for better stability and these 16 children therefore were not included in this critical study. Thus we are reporting on 24 patients, one with bilateral amputations, involving a total of 25 limbs fitted with the basic patellar tendon bearing below-knee prosthesis.

Fifteen of the experimental group are males (including one bilateral) and nine are females. The age distribution of the series at the time of fitting was eleven months to fourteen years. All, of course, had open epiphyses.

The male bilateral amputee has had but one prosthesis for each leg, while nine other males and four females fitted unilaterally also had only one PTB Prosthesis. Three males and two females have each had two prostheses and two males and three females have had three prostheses each. This makes a total of 40 prostheses fitted.

Routine X-rays of the involved knee joints to show the tibial stump and the proximal tibial and distal femoral epiphyses have been taken on an annual basis. In many cases also, both AP and lateral X-rays were taken of the child standing in the prosthesis. This has given us additional information concerning the actual weight-bearing areas and specifically whether or not the patients are actually bearing weight on the patellar tendon.

Conclusion

The children in our series have now been wearing their prostheses for periods ranging from one to almost four years.

Our observations to date, both as a result of clinical examination and analysis of X-rays taken, have not revealed any change in the epiphysial line, the epiphysis, or stump that we could attribute to the wearing of a patellar tendon bearing type of prosthesis.

In essence, our experience thus far has not identified any contraindication to fitting the Patellar Tendon Bearing Prosthesis. We shall therefore continue to use and recommend it for juvenile amputees.

Claude Lambert is Clinic Chief, University of Illinois Amputee Clinic, Chicago, Illinois