Introduction
In the Antero Cruciate Ligament reconstruction (ACLR) with hamstrings tendon, the graft anchoring needs a several weeks, and a post-operative rehabilitation might severely affect the strength of the graft anchoring.
The purpose of this study was to compare the difference of an influence between the early rehabilitation and the standard rehabilitation after ACLR to the knee stability and bone tunnels enlargement. The hypothesis was that the knee stability will be better and bone tunnel enlargement will be smaller with the standard rehabilitation than with the early rehabilitation.
Methods
Between 2015 and 2017, 40 consecutive patients undergoing anatomical double-bundle ACL reconstructions with hamstrings tendon were studied. (25 male and 15 female) patients were divided to two groups. Group A (N = 20) consisted of patients with the early range of motion (ROM) exercise and weight bearing rehabilitation undergoing surgery between 2015 and 2016, and Group B (N = 20) consisted of patients with standard rehabilitation undergoing surgery between 2016 and 2017. (Figure 1)
At the 1 year after the operation, Anterior drawer test (ADT), Pivot shift test (PST), Anterotibial translation (ATT) measured by knee arthrometer (KneeLax3), Range of motion were evaluated. The Lysholm knee score was also recorded as a subjective scoring. A 64-slice multidetector CT scanner was used for all knee and 3D image was used to evaluate the bone tunnel enlargement. The bone tunnel enlargement rate was calculated from the tunnel diameter. In a statistical analysis, Student’s t-test and Fisher’s exact test were used to compare the contralateral differences between the group A and group B. (P<0.05)
Results
As for Range of motion, Lysholm score, no significant difference between two groups were found. In the KneeLax3 testing, ATT was 1.9±1.3 at the group A and 0.3±1.3 at the group B. ATT of group B was significantly lower than ATT of group A. It the manual testing, the number of patients who had a positive ADT and positive PST were one and three at the group A, and all negative at the group B. In the CT evaluation, the tunnel enlargement rate for AM tunnel was 32.7±14.1 at the group A and 25.6±13.7 at the group B. In addition, the tunnel enlargement rate for PL tunnel was 33.5±12.7 at the group A and 34.8±13.7 at the group B.
At the AM tunnel, the tunnel enlargement of group B was significantly lower than group A.
Conclusions
It was reported that fibrous tissue continuity was re-established between the bone and the tendon after ACLR with hamstrings tendon. However, graft movement in the bone tunnel is a one of the factors to disturb the bone tendon healing. Therefore, our results showed that the early ROM exercise and weight bearing(WB) rehabilitation may prevent the graft mature and affect the knee stability at the clinical result.