From January 1981 to September 1983 forty knees had replacement of a
torn anterior cruciate ligament with a tendon xenograft. In six of the
first thirty knees that were operated on severe synovitis developed within
eight months after the operation, and total synovectomy and removal of the
graft was required. Because of this complication we changed the recommended
rinsing procedure for the graft in the last ten knees, and no synovitis
occurred in these. Approximately half of all of the grafts ruptured between
twelve and twenty months after the operation.