Andrew Luck suffered a subluxation of his throwing shoulder. A subluxation is a partial dislocation, where the shoulder comes partially out of joint, then relocates (goes back in) before it dislocates. In other words, the ball (humeral head) of the shoulder came partially out of the socket (glenoid), then was pulled back in by the muscles and tendons before it fully dislocated.
The Bones of the Shoulder
Luck’s shoulder subluxation may or may not require an arthroscopic stabilization after the season, depending on how loose the shoulder is following rehabilitation. During rehabilitation, the shoulder and shoulder blade muscles are strengthened to try to compensate for any ligament stretching that occurred. The ligament stretching that Luck suffered will lead to some degree of shoulder laxity.
Luck missed one game, but is expected to play this week. That’s possible. I think he should be able to play, but may lack top range (i.e. The ability to throw his usual top distance) and top velocity for ‘a while.’ This is because throwing far and throwing fast require full shoulder abduction-external rotation (ABER). ABER is the position that occurs when a thrower cocks his shoulder fully back to throw. It’s also the position of instability for Luck. In this position he may feel pain and/or instability, so he may not be able to cock his shoulder all the way back.
Importance of the Labrum & Ligaments of the Shoulder
I’ve read that Luck’s in-season availability will be affected by whether or not his labrum is torn. The labrum is important because the shoulder ligaments attach to the bone via the labrum, which is a meniscus-like structure around the glenoid (shoulder socket). However, I’ll respectfully disagree with this point of view. Luck’s ability to play or not this season is affected only by how unstable his shoulder is. And by how far back he can cock his shoulder into ABER during throws without feeling pain or instability. The presence or absence of a labral tear is mainly important from a technical surgical standpoint after the season if Luck elects to have his shoulder surgically repaired.
Click here too see a video of me performing an arthroscopic Bankart Repair.
Diagram of a normal shoulder, Bankart lesion, and a repaired labrum.
Arthroscopic view of a Bankart Lesion
The ligaments of the shoulder are not really defined structures like the ACL of the knee. They’re really just thickenings of the joint capsule, the balloon around the shoulder joint. Tear two chicken bones apart; the structure you tore to separate the bones is the joint capsule. There is always some degree of capsule stretching with shoulder instability. It’s like pulling on a shirt. It will stretch. It may or may not tear. Same with the shoulder’s ligaments.
The ligaments of the shoulder (SGHL, MGHL, aIGHL, pIGHL) are really just thickenings of the joint capsule (sheet of tissue between the humerus (ball) and glenoid (socket).
A shoulder with a labral tear will, on average, be less stable than one without a labral tear, but not always. So whether or not there is a labral tear is not the major issue here. How stable the shoulder feels to Luck, and whether or not he can comfortably cock his shoulder back to throw is what will determine his ability to play, and be effective, this season. From what I hear, he feels fairly comfortable throwing. He knows better than anyone but, again, he’ll still have some (as yet unknown) loss of range and velocity.
Dr. Jeffrey E. Budoff is a board-certified orthopedic surgeon who wades through misleading coach-speak and vague team injury information to offer advice for your fantasy team.