Absent Anterior Cruciate Ligament
S Vanden Bossche1, B Vanzieleghem1, H Declercq1
1Department of Radiology, AZ Sint-Blasius, Dendermonde, Belgium.
Journal of the Belgian Society of Radiology
|July 25, 2018
Summary
This case report details MRI findings for congenital anterior cruciate ligament aplasia, often with posterior cruciate ligament hypoplasia. Surgical intervention is typically unnecessary due to knee adaptation to altered biomechanics.
Area of Science:
- Orthopedic Surgery
- Radiology
- Medical Imaging
Background:
- Congenital aplasia of the anterior cruciate ligament (ACL) is a rare condition.
- Associated hypoplasia of the posterior cruciate ligament (PCL) can occur, classified as Manner type 2.
- Altered knee biomechanics are present from birth.
Purpose of the Study:
- To present the characteristic MRI findings of ACL aplasia with PCL hypoplasia.
- To highlight radiographic signs aiding in diagnosis.
- To discuss the implications for operative treatment.
Main Methods:
- Case report presentation.
- Magnetic Resonance Imaging (MRI) analysis of knee structures.
- Radiographic assessment including femoral notch width and tibial spine morphology.
Main Results:
- MRI demonstrated complete absence of the ACL.
- Associated PCL showed hypoplasia (Manner type 2).
- Radiographic findings included a shallow femoral notch and hypoplastic tibial spines (dromedar sign).
Conclusions:
- Congenital ACL aplasia can be diagnosed via specific MRI and radiographic features.
- The knee often adapts to the altered biomechanics, making surgery unnecessary in most cases.
- Conservative management is generally recommended.
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