Ortho Dx: A double posterior cruciate ligament sign - Clinical Advisor

Ortho Dx: A double posterior cruciate ligament sign

Slideshow

  • Magnetic resonance imaging of a 31-year-old man with right knee pain following a soccer injury shows a double posterior cruciate ligament sign

    Slide

    Magnetic resonance imaging of a 31-year-old man with right knee pain following a soccer injury shows a double posterior cruciate ligament sign

  • Coronal magnetic resonance imaging of this patient shows absence of the medial meniscus in the medial compartment and a meniscal fragment in the inferior medial intercondylar notch

    Slide

    Coronal magnetic resonance imaging of this patient shows absence of the medial meniscus in the medial compartment and a meniscal fragment in the inferior medial intercondylar notch

A 31-year-old man presents with right knee pain after a soccer injury 1 week earlier. He was running and making a cutting movement when he felt something in his knee “pop.” He was unable to continue playing, and his knee has been swollen ever since. The patient is also having trouble bearing weight and cannot fully extend his right knee. Magnetic resonance imaging shows a double posterior cruciate ligament sign.

This case has been brought to you in partnership with the Journal of Orthopedics for Physician Assistants.

The patient presents with a large bucket handle medial meniscus tear with a large meniscal fragment displaced into the intercondylar notch. This appears as a second smaller posterior cruciate ligament (PCL) on sagittal magnetic resonance images (double PCL sign). The...

Submit your diagnosis to see full explanation.

The patient presents with a large bucket handle medial meniscus tear with a large meniscal fragment displaced into the intercondylar notch. This appears as a second smaller posterior cruciate ligament (PCL) on sagittal magnetic resonance images (double PCL sign). The displaced meniscus lies parallel and anterior inferior to the PCL.

A double PCL sign is highly specific for a displaced bucket handle meniscus tear. The coronal magnetic resonance image taken of the patient described also shows absence of the medial meniscus in the medial compartment and a meniscal fragment in the inferior medial intercondylar notch.1

A displaced bucket handle tear often causes a mechanical block to knee extension, as seen in this patient. Bucket handle tears commonly occur in conjunction with other ligamentous injuries, including medial collateral and anterior CL tears.

A true vertical bucket handle meniscus tear that occurs in the red zone or vascular zone is usually amenable to repair. The decision to repair or resect the tear is often made at the time of arthroscopic surgery. Meniscus repair, which is often done in conjunction with anterior CL reconstruction, is preferable in the younger population (age <35-40 years) to preserve articular cartilage over time. Meniscectomy is generally preferred in those aged older than 40 years, in whom chondral wear is already present.2

Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor-in-chief of the Journal of Orthopedics for Physician Assistants (JOPA).

References

  1. Weerakkody Y, Gaillard F. Double PCL sign. Radiopaedia.org. https://radiopaedia.org/articles/double-pcl-sign. Accessed January 3, 2017.
  2. Sommers J, Collins M. Meniscal Tears: Repair or Resect. Journal of Orthopaedics for Physician Assistants. 2013;1:11-15. 
Next hm-slideshow in Ortho Dx