Bone tunnel enlargement after anterior cruciate ligament reconstruction with semitendinosus tendon using Endobutton fixation on the femoral side

We evaluated 29 knees with a minimum follow-up of 2 years after anterior cruciate ligament (ACL) reconstruction using doubled autogenous semitendinosus tendons. On the femoral side, a 5-mm Mersilene tape (Ethicon, Norderstedt, Germany) with an Endobutton (Acufex Microsurgical, Mansfield, MA) was used. The tendon was fixed on the tibial side with two staples. Regarding the IKDC score, 66% of the patients were graded as normal or nearly normal. The anterior laxity side-to-side difference (KT 1000, man-max-drawer) was under 3 mm in 55% and under 5 mm in 90%. Radiographs taken in the lateral and anteroposterior projections of the knee showed sclerotic bone tunnel margins. The diameter of the bone tunnels were measured, corrected for magnification, then compared with the original reamed diameter to determine any change in size. Enlargement of at least 2 mm was identified in 72% of the femoral tunnels and 38% of the tibial tunnels. No correlation was found concerning the enlargement of the tunnel and the IKDC score or the residual joint laxity. We conclude that using an Endobutton-Mersilene construct in ACL reconstruction leads to femoral and tibial bone tunnel enlargement at follow-up of 2 years.