USE OF ALLOGRAFTS AFTER FAILED TREATMENT OF RUPTURE OF THE ANTERIOR CRUCIATE LIGAMENT

A prospective study was done of the use of allogeneic tissue to recons truct the anterior cruciate ligament in knees in which an intra-articu lar or an extra-articular operation had failed. Sixty-six consecutive patients (sixty-six knees) had such an operation with use of bone-pate llar ligament-bone allografts; all but one returned for follow-up eval uation twenty-three to seventy-eight months (mean, forty-two months) a fter the operation. A total of 235 previous operations had been perfor med in these sixty-six knees, including eighty-one procedures for rupt ure of the anterior cruciate ligament. The results of the allograft pr ocedure were evaluated with a subjective and objective system that rat ed twenty factors. The anterior-posterior displacement was substantial ly improved in most of the patients. According to data derived from ar thrometric studies and pivot-shift tests of the fifty-seven patients w ho were so evaluated and in whom the condition was unilateral, 53 per cent (thirty) of the reconstructed ligaments were determined to be fun ctional; 21 per cent (twelve ligaments), partially functional; and 26 per cent (fifteen ligaments), a failure. When we calculated the rate o f failure by including ten failures that had occurred within two years after the operation with the fifteen that occurred in patients who ha d been followed for at least two years, the over-all rate of failure w as 33 per cent (twenty-five of seventy-five operations). There was sig nificant improvement in the subjective ratings of functional limitatio ns and symptoms (p < 0.01) and in the over-all rating score (p < 0.000 1). However, there was a significant difference between the scores of the patients in whom the surfaces of the articular cartilage had appea red normal at the index operation and those of the patients in whom th ere had been noteworthy fissuring and fragmentation or exposure of sub chondral bone. After the program of rehabilitation, which included imm ediate motion of the knee, a range of motion of 0 to 135 degrees was r estored in all but five knees, four of which lacked only 5 degrees of this extent of flexion or extension. The results demonstrate that bone -patellar ligament-bone allografts may be used when proper autogenous tissues are not available and that symptoms and abnormal displacement were reduced in most of our patients.