Hey everyone! I’ve been diving deep into anatomy for my massage therapy studies, and I thought I’d share some insights on the rotator cuff muscles. These muscles get a lot of attention because they’re crucial for shoulder stability, but also prone to injury. Whether you’re into anatomy, massage therapy, physical therapy, or just curious about how your body works, here’s a quick overview:

The Rotator Cuff Muscles (aka “SITS” Group)

The rotator cuff is made up of four key muscles, often remembered by the acronym “SITS”:

• Supraspinatus
• Location: Runs along the top of the shoulder blade (scapula)
• Action: Initiates abduction of the shoulder (raising the arm out to the side)
• Common Issues: Prone to impingement because of its position under the acromion
• Infraspinatus
• Location: Just below the spine of the scapula
• Action: Externally rotates the shoulder (turns the arm outward)
• Common Issues: Often tight in people with poor posture or heavy lifting habits
• Teres Minor
• Location: Along the outer edge of the scapula, below the infraspinatus
• Action: Assists with external rotation and helps stabilize the shoulder joint
• Common Issues: Rarely injured alone but can work overtime if the other muscles are weak
• Subscapularis
• Location: On the front surface of the scapula, sitting directly against the rib cage
• Action: Internally rotates the shoulder (turns the arm inward)
• Common Issues: Can become tight with repetitive pushing motions, which can cause shoulder pain

Functions and Importance

• Stabilization: The rotator cuff muscles work together to hold the head of the humerus securely in the shallow shoulder socket (glenoid cavity). Without them, the shoulder would be at a high risk of dislocation.
• Range of Motion: These muscles allow for a wide range of shoulder movements, from lifting to rotating, which are essential in sports, daily activities, and physical work.