The course of the patellar tendon after reharvesting its central third for ACL revision surgery: a long-term clinical and radiographic study

The choice of the optimal graft for anterior cruciate ligament (ACL) revision surgery is still controversial. Reharvesting the patellar tendon has been suggested as one graft alternative. Our hypothesis was that in the long-term, ACL revision surgery using reharvested patellar tendon autografts would render a good clinical outcome and a normal patellar tendon at the donor site as seen on magnetic resonance imaging (MRI). Fourteen consecutive patients (five women, nine men), who underwent ACL revision surgery using reharvested ipsilateral patellar tendon grafts, were included in the study. They underwent bilateral MRI evaluations of the patellar tendon and were tested for clinical outcome 26 (20–35) and 115 months (102–127) after the revision procedure. On the second occasion, they also underwent standard weight-bearing X-ray examinations.

The serial MRI evaluations revealed that the thickness of the patellar tendon at the donor site was significantly increased compared with the non-harvested, normal contralateral side and that the donor-site gap was still visible after 10 years. No significant differences were seen between the 2- and 10-year MRI evaluations. Standard weight-bearing X-ray examinations revealed signs of mild degenerative changes in all patients. Clinical results in terms of the Lysholm score, IKDC evaluation system, one-leg-hop test, KT-1000 laxity test and the knee-walking test revealed no significant differences between the 2- and 10-year assessments. In overall terms, the clinical results were considered to be poor on both occasions. The patellar tendon at the donor site had not normalised 10 years after the reharvesting procedure, as seen on MRI. Furthermore, the clinical results were poor after ACL revision surgery using reharvested patellar tendon autograft.