The transtibial vs. anteromedial portal technique for ACL reconstruction: is there a difference in MRI signal intensity of the graft

Rupture of the anterior cruciate ligament (ACL) is a frequently seen (sport)
injury mostly induced by a non-contact deceleration motion and can be treated
by ACL reconstruction surgery. There are two primary surgical techniques to
reconstruct the ACL: transtibial (TT) technique or anteromedial portal (AMP)
technique. Currently, there is no evidence which surgical technique elicits the
best clinical and functional outcomes. However, these assessments are an
indirect measure of the graft integrity and require large numbers of patients
to detect differences between both operation techniques. There is a need for a
quantitative in vivo measurements method for the evaluation of the
biomechanical performance of the ACL graft. MRI-derived measures of the signal
intensity (SI) of the ACL graft have been described as an independent predictor
of graft properties. MRI assessment with proton density weighted imaging (PDWI)
fails to correlate with actual graft function. A more promising technique is
T2*-weighted gradient-echo MRI imaging which has been reported as a useful
imaging modality to assess graft integrity. This leads to our research
question: Is there a difference in SI of the ACL graft on MRI, one year after
ACL reconstruction, between TT and AMP reconstruction technique?

To conduct a randomised controlled trial to determine differences in outcomes
of the TT and AMP ACL reconstruction techniques by means of MRI signal SI of
the ACL graft. Secondly, differences in clinical, functional and
patient-oriented outcomes of the TT and AMP ACL reconstruction techniques will
be assessed. Additionally, differences between MRI SIR assessment with the
current MRI protocol (PDWI and PDWI SPAIR imaging protocol) and the additional
T2*WI gradient echo protocol will be assessed.

A randomised controlled trial will be executed. Patients will be randomly
allocated to undergo ACL reconstruction by means of the TT and AMP drilling
technique. The trial will be conducted at the department of Orthopaedics of the
Martini Hospital Groningen.

Patients in the study group will undergo ACL reconstruction using the AMP
technique. This technique will be compared to the conventional TT technique for
ACL reconstruction in the control group.

Since both the TT and AMP technique for ACL reconstruction are standard
techniques for ACL reconstruction, no additional risks are associated with
participation of the study. No additional risks are involved with the MRI.