Background
One of the most widespread procedure to restore anterolateral stability is the lateral extra-articular tenodesis (LET). Clinical outcomes after association of a LET to ACL reconstruction (ACL-R) have been widely investigated, however potential influence of LET over the ACL ligamentization process have not been taken in account yet.
Purpose
To compare on a 10 months postoperatively MRI, the maturity of the grafts after ACL hamstring autograft reconstruction associated or not with a LET.
The hypothesis was that when modified Lemaire LET (MLLET) is performed, the MRI parameters of ACL graft maturity are modified.
Study Design:
Retrospective comparative cohort study
Methods
Patients who had undergone an anatomic ACL-R combined or not with MLLET and had had MRIs 10 months postoperatively from December 2017 to December 2018 were included.
30 isolated ACL-R and 22 ACL-R plus MLLET were included. The two groups were comparable based on all the criteria analyzed.
To evaluate graft maturity, the signal-to-noise quotient (SNQ) was measured in three regions of interest (ROIs) of the proximal, mid-substance and distal ACL graft. Lower SNQ ratios indicate less water content and theoretically better maturity and healing of the graft.
Results
The mean SNQ was 4.62 (SD 4.29; range 3.12-6.19) for the isolated ACL-R group and 7.59 (SD 4.68; range 4.38-8.04) in the ACL plus MLLET (P = 0.012).
Upon comparing the mean values of the three portions of one group to those of the other group, we found that only at the proximal and middle portions was there a significant difference between the 2 groups (p=0.007 and p=0.049, respectively) while no differences were identified (p=0.369) in the distal third.
Conclusion
At the 10-month follow-up, hamstring tendon autografts for anatomic ACL reconstruction associated with MLLET do not show the same MR signal intensity compared to an isolated hamstring anatomic ACL reconstruction.
Keywords: ACL reconstruction; ligamentization; lateral extra-articular tenodesis. graft incorporation.