MR patterns of denervation around the shoulder

Area of Science:

• Radiology
• Neurology
• Orthopedics

Background:

• Shoulder pain diagnosis traditionally relies on clinical assessment and electrophysiologic studies.
• Magnetic Resonance Imaging (MRI) plays a crucial role in evaluating shoulder pain of uncertain origin.
• MRI can identify direct and indirect signs of neuropathy, nerve compression, and space-occupying lesions.

Purpose of the Study:

• To present the relevant anatomy, causes, clinical features, and MR appearances of nerve injury and muscle denervation in the shoulder girdle.
• To highlight MRI's utility in diagnosing denervation injury as a cause of shoulder pain.
• To guide clinicians in utilizing MRI findings for accurate diagnosis and management.

Main Methods:

• Review of relevant anatomical structures of the shoulder girdle.
• Discussion of common causes of nerve injury and muscle denervation.
• Presentation of characteristic MRI findings associated with nerve injury and denervation.
• Correlation of clinical features with imaging findings.

Main Results:

• MRI can confirm the presence of nerve compression and identify space-occupying lesions.
• Indirect signs of muscle denervation, such as fatty infiltration and atrophy, are detectable by MRI.
• MRI assists in excluding other intrinsic shoulder pathologies.

Conclusions:

• MRI is valuable in determining the morphologic cause, precise location, and duration of nerve injury and muscle denervation.
• Knowledge of anatomy and imaging findings aids in making treatable diagnoses and avoiding unnecessary procedures like biopsy or surgery.
• MRI findings are critical for differentiating nerve injury from inflammatory or neoplastic conditions.