Magnetic resonance imaging after anterior cruciate ligament reconstruction: A practical guide

Abstract

Anterior cruciate ligament (ACL) reconstruction is one of the most common orthopedic procedures performed worldwide. In this regard, magnetic resonance imaging (MRI) represents a useful pre-operative tool to confirm a disruption of the ACL and to assess for potential associated injuries. However, MRI is also valuable post-operatively, as it is able to identify, in a non-invasive way, a number of aspects and situations that could suggest potential problems to clinicians. Graft signal and integrity, correct tunnel placement, tunnel widening, and problems with fixation devices or the donor site could all compromise the surgical outcomes and potentially predict the failure of the ACL reconstruction. Furthermore, several anatomical features of the knee could be associated to worst outcomes or higher risk of failure. This review provides a practical guide for the clinician to evaluate the post-surgical ACL through MRI, and to analyze all the parameters and features directly or indirectly related to ACL reconstruction, in order to assess for normal or pathologic conditions.

Assessment of Anterior Cruciate Ligament Graft Maturity With Conventional Magnetic Resonance Imaging: A Systematic Literature Review

“…6,18,57 MRI signal intensity (SI) measurements are also being used increasingly in clinical studies to assess maturity of the ACL graft in humans. 21 In the 1990s, Howell et al 26 were among the first to propose an MRI grading system that categorized the signal measured in the ACL graft as low, intermediate, or high, where the lower the SI, the more “mature” the reconstructed graft was assumed to be. However, SI in conventional “weighted” MRIs is expressed in relative units that are dependent on acquisition parameters and scanner characteristics.…”

Clinical and radiological outcome after Anterior Cruciate Ligament Reconstruction using the T-Lock Osteotrans resorbable Tendon Anchor: Early Experience and Midterm Follow-up

“…The MRI evaluation with 1 year and in some patients till 3 year postoperatively can be relatively short since evolving biologic activity and graft incorporation continues well beyond 1 year following ACLR [14]. Yet graft maturation was very good with only 1 patient showing a hyperintense signal on the MRI which suggests an incomplete graft maturation [8]. In patients with follow-up MRIs, no tunnel enlargement was seen compared to the 1-year result.…”

Review of magnetic resonance imaging features of complications after anterior cruciate ligament reconstruction

“…tears of the patellar tendon, bursitis and haematoma. (8) Following harvesting, it is normal to see tendon thickening and a central gap within the patellar tendon corresponding to the site of tendon harvesting, which usually fills in with reparative tissue by two years. (9) Donor site complications of hamstring tendon grafts are relatively rare, with the most common complication being a fluid collection at the donor site.…”