Abstract
The present study was conducted to analyze the specific morphological features of press-fitted quadriceps tendon-patellar bone grafts that determine primary graft stability in ACL-reconstruction.
Ten quadriceps tendon-patellar bone grafts were harvested from fresh frozen human cadaveric knees (age 52–82) and fixed to porcine femora in a press-fit technique. Four specimens were prepared for histological analysis of the bone-tendon junction, while a modified technique for tissue-plastination was applied to 6 specimens to investigate the microscopic and microradiographic features of the bone-to-bone interface.
Analysis of the bone-tendon junction revealed a serious damage of the fibrocartilage at the attachment zone according to the impaction of the patellar bone plug with implantation. Microradiographs and microscopy of the plastinated specimens showed that there is a trabecular interaction between the bony interfaces of the graft and the femoral tunnel, representing an early osseous integration with local increase of radiopacity. In consequence, both elevated compressive forces as well as increased frictional resistance seem to contribute to the primary stability of press-fit fixated grafts.
The stability of quadriceps tendon-patellar bone grafts in press-fit technique to a certain degree depends on bone quality, allowing compressive forces to arise at the bone-to-bone interface. Loss of graft stability, however, is caused by disturbance of the integrity of the bone-tendon junction while impacting the patellar bone plug into the femoral tunnel.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
