MRI findings of Stener-like lesion of the knee: A case series with surgical correlation.

PURPOSE

To describe the MRI findings of the "Stener-like" lesion of the knee and its distinction from simple medial collateral ligament (MCL) tear. A "Stener-like" lesion of the superficial medial collateral ligament is a tear involving the distal fibers, where the torn fibers become displaced superficial to the pes anserinus fibers, a displacement which can prevent healing.

METHODS

Nine cases of Stener-like lesion were prospectively diagnosed on MRI. Retrospective, IRB-approved, HIPAA-compliant chart review was performed to determine correlation of surgical and MRI findings. Seven cases were surgically confirmed and are included in the series.

RESULTS

MRI is useful in making the diagnosis of Stener-like lesions and prompting the surgeon to explore the distal MCL. Coronal MRI shows variable proximal retraction of the torn ligament. It has a lax contour and abuts the pes anserinus. The proximity of the torn ligament end to the pes can result in misdiagnosis of a partial tear. Axial images are useful to confirm position of the ligament superficial to the pes. All cases had associated tear of the deep MCL fibers, as well as sprains of the proximal superficial MCL.

CONCLUSIONS

It is important to recognize the Stener-like lesion because this lesion is usually managed surgically, while most MCL tears are managed conservatively. The presence of injury to the proximal MCL is usually present, and may be a distractor from the distal injury. Care must be taken to include the distal attachment of the sMCL on coronal MRI images.