Six months ago when I started thinking about shoulder surgery, I realized I didn’t know a whole lot about how shoulders work. Since then I have learned:

• It’s one of the most complicated joints in my body, a ball-and-socket joint that lets my arm move in a bunch of different directions.
• It’s a very unstable joint, as the ball (the humerus) is much bigger than the socket (the glenoid cavity). This instability is great for range of motion but makes it prone to injury.
• (In case you don’t know, ligaments attach bones to bones, while tendons attach muscles to bones.)
•  There are four rotator cuff muscles (supraspinatus, infraspinatus, teres minor, subscapularis) and their tendons join together to form the rotator cuff.  This cuff, along with the ligaments in the glenoid cavity, stabilize the humerus to keep it in the shallow glenoid socket.

WebMd has two short articles with nice drawings of the shoulder bones, muscles, & tendons:

• What is my rotator cuff and why does it hurt?
• Picture of a Shoulder

I have watched a bunch of YouTube videos about the rotator cuff and the shoulder. Here are the ones I liked best:

• Here’s a pretty good video explaining the four rotator cuff muscles.
• Here’s another good video on the rotator cuff.
• And this video gives a good explanation of all the parts of the shoulder.
• This video actually  shows the inside of the shoulder during an arthroscopic evaluation of a normal shoulder. It’s not as gory as it sounds.

Here are the results of my MRI, first in the original Spanish and then translated by Google:

• El estudio demostró ruptura a nivel de la inserción del tendón supraespinoso
• Cambios en la intensidad de señal a nivel del tendon del subescapular mas presencia de lesiones de tipo osteocondral
• Cambios inflamatorios sobre el ligamiento gleno-humeral y proceso de artrosis a nivel de la articulación acromioclavicular.  Mismo tendón muestra cambios intrasustancia
• Relación articular estable en el espacio gleno-humeral

• The study showed rupture at the insertion level of the supraspinatus tendon
• Changes in signal intensity at subscapular tendon level plus presence of osteochondral-type lesions
• Inflammatory changes on the glenohumeral ligament and process of osteoarthritis at the level of the acromioclavicular joint. Same tendon shows intrasubstance changes
• Stable articular relationship in the glenohumeral space

So, I have a rupture or tear in the supraspinatus tendon where it attaches to the humerus.  This tear will be repaired and the tendon reattached to the humerus.

I have problems with my subscapular tendon, including lesions (I think they are like cysts) which I think leaked from a tear in the bursa.These cysts will be cleaned out and any tears repaired. I’m  not sure how la intensidad de señal (signal intensity) should have been translated. It might be “scar” or “amount scarring.”

I have inflammation in one of the glenohumeral ligaments; the glenohumeral joint is what the doctors call the shoulder ball and socket. .If this involves the long head of the biceps (which attaches in this area), my doctor may move this bicep tendon to a better location. I’m not sure what else he might do in this area.

And I may have bone spurs on the bottom of the acromion bone (“process of osteoarthritis at the level of the acromioclavicular joint”). If so, these will be smoothed off to provide more space between the acromion and the humerus and prevent the bone spurs from causing pain and damage.

(If one of you medical types spots an error in the translation or my statements, please let me know. Thanks!)