Rotator cuff muscles

The four rotator cuff muscles work with each other synergistically to allow shoulder movement in various positions. We make use of the shoulder in almost every yoga pose and it is important to know to anatomy of the delicate and unstable muscles.

As a group, the rotator cuff directs and stabilizes the humeral head within the glenoid while the larger extrinsic muscles like the ltissimus dorsi, pectoralis major and deltoid produce the forces necessary for gross arm and shoulder movements.

Rotator cuff Muscles
The rotator cuff muscles are SITS :
supraspinatus, infraspinatus, teres minor and subscapularis.

1. Supraspinatus
Location: The supraspinatus originates from the supraspinatus fossa of the scapula and inserts at the greater tubercle of the humerous

Function: Supraspinatus work closely with the deltoid to raise the arm in flexion and abduction.

2. Infraspinatus
Location: The infraspinatus originates from the infraspinatus fossa on the posterior surface of the scapula and inserts at the greater tubercle of the humerus

Function: Infraspinatus primarily acts with the arm in neutral. The infraspanatus have diagonal fibers. The diagonal orientation of the fibers create external rotation of the arm and shoulder.

3. Teres Minor
Location: The teres minor originates at the lateral border of the scapula and inserts to the greater tubercle of the humerus.

Function: Like the infraspinatus, the teres minor also create external rotation of the arm and shoulder.

4. Subscapularis
Location: The subscapularis originates from the subscapular fossa on the anterior surface of the scapula, and inserts on the lesser tubercle of the humerus.

Function: Subscapularis is the main internal rotator of the shoulder.

In short, this 4 muscles wrap around the scapulae from the top, posterior, anterior and bottom. They have different functions but work together to stabilize the shoulder.

Injury prevention
The most common injuries to the rotator cuff include: primary & secondary impingement, tendonitis , rotator cuff tears.
Factors leading to injuries are as follow: acute or repetitive trauma, excessive tension, improper exercise selection and technique.

As rotator cuff injuries are common, it is important to strengthen these muscles and not overwork them. Knowledge of the biomechanics aids in selecting stretching exercises. In order to prevent injury, exercises to isolate and strengthen the rotator cuff muscles are important.

Some of the asanas that we can choose to stretch and strengthen shoulder are :Melting Heart Posture (Anahatasana), Eagle Pose (Garudasana), Rabbit Pose(Sasangasana), Bow Pose (Dhanurasana), Intense Side Stretch Pose( Parvottanasana), Pose dedicated to the Sage( Marichiyasana), Downward Dog (Adho Mukha Svanasana), Plank(kumbhaksaana), Headstand (sirsasana).

ZJ Chung