Learning objectives
Recognize the various accessory muscles around the ankle on MR imaging and delineate their relationship to adjacent structures.
Diagnose them as incidental findings and correlate their clinical significance in symptomatic patients.
Differentiate between accessory muscles and soft tissue tumors.
Learn the origin,
insertion and course of various accessory muscles of the ankle.
Background
Various Accessory muscles around the ankle are recognized.
Most of them are typically asymptomatic and diagnosed as incidental findings,
butin symptomatic patients they can cause pain,
nerve compression,
compartment syndrome,
orhind foot rigidity.
At times they mimicsoft tissue tumors.
Magnetic resonance imaging (MRI) is the modality of choice in diagnosing accessory muscles,
delineating their relationship to adjacent structures and differentiating them from soft tissue tumors.
Accessory muscles are isointense to skeletal muscle on all pulse sequences while soft tissue neoplasms show increased signal intensity on...
Findings and procedure details
MR Imaging of Ankle
MRI is the best imaging modality for diagnosing accessory muscles around the ankle.
The general sequences used in a non-contrast enhanced study include
T1 weighted images
T2 weighted images
STIR
PD weighted images
Images are taken in all three planes.
Comparison with other modalities
MRI is superior toother modalities like CT or ultrasound by giving better contrast resolution and delineating the course of the muscles which differentiates it fromother soft tissue tumors.
Accessory Ankle Muscles
1.
Flexor digitorum accessorius Longus
Origin:...
Conclusion
Diagnosing accessorymuscles is crucial in the setting of asymptomatic as well as symptomatic patients,to avoid misdiagnosis and also to aid treatment options.
MRI is the modality of choice for detecting accessory muslces,
their specific location and course.
MRI aids in differetiating them from soft tissue masses through their specific MR characteristics.
Personal information
Dr.
Samra Abid Qureshi
Clinical Fellow in Women's Imaging
Clinical Imaging Deratment
Hamad Medical Corporation
Doha,
Qatar
+974-66100898
[email protected]
[email protected]
Dr.
Hiba Esmayil
Radiology Resident
Clinical Imaging Department
Hamad Medical Corporation
Doha,Qatar
+974-66804708
[email protected]
Dr.
Syed Intikhab Alam
Specialist
Musculoskeletal Imaging
Hamad Medical Corporation
Doha,
Qatar
+974-55176759
[email protected]
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Bilateral four-headed biceps brachii muscles: the median nerve and brachial artery passing through a tunnel formed by a muscle slip from the accessory head.Clin Anat1998; 11:209–212.
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