The shoulder labrum is a piece of soft cartilage in the socket-shaped joint in the shoulder bone. It cups the ball-shaped joint at the top of the upper arm bone, connecting the two joints.
A group of four muscles called the rotator cuff helps the labrum keep the ball in the socket. This allows your upper arm to rotate.
Types of shoulder labrum tears-
The shallow, socket-like opening of the shoulder where the labrum is located is called the glenoid. Shoulder labrum tears can happen anywhere around the glenoid socket.
There are three main types of labrum tears:
- SLAP tear or lesion: When the tear is above the middle of the glenoid, it’s called a SLAP tear or SLAP lesion. SLAP stands for “superior labrum, anterior to posterior,” which means front to back.
- Bankart tear or lesion: When the damage is to the lower half of the glenoid socket, it’s called a Bankart lesion or tear. Bankart tears are more common in younger people with dislocated shoulders.
- Posterior labrum tear: Injuries to the back of the shoulder joint can cause a posterior labrum tear.
Traumatic injury and wear and tear from repetitive motion of the upper arm can both cause labrum tears.
Some specific causes of labrum tears include:
- A fall on an outstretched arm
- A direct hit to the shoulder
- A violent blow while reaching overhead
- A sudden tug on the arm