Skeletal Radiology

, Volume 46, Issue 11, pp 1575–1578 | Cite as

Incarceration of the medial collateral ligament in the intercondylar notch following proximal avulsion

  • Edward WaltonEmail author
  • Martin Williams
  • James R. Robinson
Case Report


Intra-articular entrapment of the medial collateral ligament (MCL) is a rare but recognised complication of traumatic injury to the posteromedial corner (PMC) of the knee. Considering the MCL is the most commonly injured ligament of the knee this complication is extremely rare with only a handful of cases describing MCL entrapment following distal avulsion of the MCL. We present the first known case of MCL entrapment following proximal avulsion of the MCL and posterior oblique ligament (POL) with the mid-substance of the MCL becoming entrapped in the joint, lying on the superior surface of the medial meniscus and extending up into the intercondylar notch. In addition, the medial patellar retinaculum was also entrapped in the medial aspect of the medial patellofemoral joint. MCL entrapment is best treated with expeditious surgical intervention and it is therefore crucial that the MRI findings are not overlooked. Details of the clinical assessment, MRI and operative findings are presented with a literature review of MCL entrapment.


MCL Posteromedial corner Intra-articular Entrapment Incarceration 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no competing interests.

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© ISS 2017

Authors and Affiliations

  • Edward Walton
    • 1
    Email author
  • Martin Williams
    • 2
  • James R. Robinson
    • 3
  1. 1.Department of RadiologyFiona Stanley HospitalPerthAustralia
  2. 2.Department of RadiologyNorth Bristol NHS TrustBristolUK
  3. 3.Bristol Knee Group, Avon Orthopaedic CentreBristolUK

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