End-bearing characteristics of patellar-tendon-bearing prosthesis--a preliminary report.

The present work was aimed at investigating the degree of participation of the stump end in the weightbearing process in PTB prostheses. Despite the belief that the stump end is not capable of withstanding high loads, it was revealed that most patients can bear from 15 percent up to 45 percent and more of their weight on the stump end. The limited number of patients studied diminishes the statistical significance, but the results of this work do suggest that the weightbearing mechanism of a PTB prosthesis can be further improved by transferring more load through the stump end. It is suggested that a nondestructive technique for assessing the end-bearing efficiency of the prosthesis be developed. Also, the criteria for design of the socket end in order to produce the desired load-bearing features needs further investigation.