01/06/2026
💡 Master the Rotator Cuff: The "SITS" Muscles Explained! 🧠
Studying the shoulder complex doesn’t have to feel like an uphill battle. Whether you are a student prepping for exams or a clinician reviewing the basics, mastering the SITS muscles is fundamental to understanding shoulder stability and biomechanics.
As shown in the infographic, here is your quick-reference breakdown of the four dynamic stabilizers of the glenohumeral joint:
1️⃣ Supraspinatus
Main Action: Starts arm lifting.
Clinical Role: Helps shoulder abduction.
Easy Tip: This is the most commonly injured rotator cuff muscle!
2️⃣ Infraspinatus
Main Action: Rotates the arm outward (external rotation).
Clinical Role: Provides vital joint stability.
Easy Tip: Highly active during throwing movements.
3️⃣ Teres Minor
Main Action: Assists with external rotation.
Clinical Role: Supports overall shoulder control.
Easy Tip: Works hand-in-hand as a duo with the infraspinatus.
4️⃣ Subscapularis
Main Action: Rotates the arm inward (internal rotation).
Clinical Role: Acts as a powerful dynamic stabilizer for the front of the shoulder.
Easy Tip: This is the largest muscle of the rotator cuff group.
⚠️ Why It Matters Clinically
When these muscles are functioning optimally, they ensure smooth, pain-free arm movement. However, when injury or weakness occurs, patients often present with pain, weakness, or significantly reduced motion.
📌 Bookmark this post so you can easily pull up this quick revision guide during your study sessions or clinical practice!