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The double ACL sign: an unusual bucket-handle tear of medial meniscus

Koji Takayama1, Takehiko Matsushita, Tomoyuki Matsumoto

  • 1Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Chuo-ku, Kobe, 650-0017, Japan.

Knee Surgery, Sports Traumatology, Arthroscopy : Official Journal of the ESSKA
|February 22, 2011
PubMed

Insights

A new magnetic resonance imaging (MRI) sign, the "double anterior cruciate ligament (ACL) sign," helps identify bucket-handle meniscus tears. This finding aids in diagnosing displaced medial meniscus tears, improving knee injury assessment.

Area of Science:

  • Orthopedic Surgery
  • Radiology
  • Sports Medicine

Background:

  • Meniscal bucket-handle tears are common knee injuries.
  • Characteristic magnetic resonance imaging (MRI) signs are used for diagnosis.
  • Accurate identification is crucial for effective treatment planning.

Observation:

  • A 17-year-old male presented with left knee pain.
  • Preoperative MRI revealed a medial meniscus tear with a displaced fragment.
  • The displaced fragment mimicked a second anterior cruciate ligament (ACL).

Findings:

  • A novel MRI sign, termed the "double ACL sign," is described.
  • This sign represents a bucket-handle medial meniscus displaced anteriorly.
  • Arthroscopy confirmed a longitudinal tear from the anterior to posterior horn of the medial meniscus.

Implications:

  • The "double ACL sign" offers a new diagnostic marker for bucket-handle meniscus tears.
  • This finding can enhance MRI interpretation accuracy for knee injuries.
  • Improved diagnosis can lead to timely and appropriate surgical intervention.

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