Learning objectives
To describe the normal magnetic resonance (MR) imaging appearance of the intrinsic muscles of the hand.
To review normal anatomy and function of the intrinsic muscles of the hand including the lumbrical,
interosseous,
thenar and hypothenar muscles.
To discuss anatomical variants and common pathologies such as denervation syndromes,
trauma- and exercise-induced changes,
myositis,
and (pseudo-) tumors.
Background
Like other skeletal muscles,
the intrinsic muscles of the hand can be affected by various conditions resulting in change of morphology or MR imaging appearance.
Detailed knowledge about normal MR imaging appearance,normal anatomy,
as well as common normal variants and pathologies is always crucial for correct diagnoses.
This educational poster will review the anatomy and function of the intrinsic muscles of the hand and will use clinical cases to illustrate some typical findings in common pathologies as followed:
Normal Imaging Findings
Function and Anatomy
Hypothenar...
Imaging findings OR Procedure Details
Normal Imaging Findings
Normal MR imaging appearance of the intrinsic muscles of the hand is not different from the appearance of other skeletal muscles.
On non fat suppressed T1,
T2 and intermediate weighted MR images,
muscles are typically intermediate intense compared with the hyperintense signal of fat or the hypointense signal of cortical bone.
On fat suppressed T1,
T2 and intermediate weighted images,
muscles typically appear hypointense as compared to cartilage or joint fluid on T2 weighted sequences.
Other than at larger extremities as for...
Conclusion
Evaluation of the intrinsic muscle of the hands needs detailed knowledge about the normal anatomy and normal variants.
Various abnormalities may affect the muscles but can reliably be detected when radiologists are familiar with the muscles' normal MR imaging appearance and typical MR imaging findings of common pathologies.
References
Acknowledgements:
Musculoskeletal images (Fig.
2,
Fig.
3,
Fig.
4,
Fig.
5)are from the University of Washington "Musculoskeletal Atlas: A Musculoskeletal Atlas of the Human Body" by Carol Teitz,
M.D.
and Dan Graney,
Ph.D.
Selection of References:
Yu JS,
Habib PA.
Normal MR imaging anatomy of the wrist and hand.
Magn Reson Imaging Clin N Am 2004;12(02):207–219.
Andreisek G.MRI of the Intrinsic Muscles of the Hand.Seminars in Musculoskeletal Radiology,21(4),
392-402.
Timins ME.
Muscular anatomic variants of the wrist and hand:findings on MR imaging.
AJR Am J...