Phew, it’s been a crazy few weeks at school since my last post. Midterms are over so time for the second installment of the injury analysis posts. Today I want to discuss one of the most injury prone parts of the body for climbing: the shoulder. The reason the shoulder is so prone to injury is because of how useful it is! Think about the range of motion you have in your shoulder; it’s really pretty impressive mechanically. To allow for that range of motion, the shoulder joint is not very sturdy, like say a knee or elbow. So unlike the simple hinge joint of the knee or elbow, the shoulder requires much more musculature to create stability. The muscles of the shoulder are known as the rotator cuff, which consists of four different muscles seen below.
This is something that I, as an engineer, really love to do when looking at anatomy. If you look at the attachments of the muscles you can start to see how they each function. The infraspinatus and teres minor connect at the outside of the shoulder and the back edge of the shoulder blade, so when these contract, the humerus is rotated externally. The supraspinatus connects at the top of the humurus and the upper edge of the shoulder blade. When this muscle contracts, it creates torque at the top of the humurus and raises the arm out to the side. Finally, the subscapularis connects on the inside of the shoulder blade and wraps forward following the rib cages then curves back out to attach to the front of the humurus. Here’s a better picture:
This one is in opposition to the external rotators. Pretty cool right? All these muscles working in harmony to create an extremely functional joint. Now if you think about these muscles, or rather the motions they produce, while climbing you can start to see why shoulder impingement is so common. When’s the last time you were climbing and had to do a really hard external rotation? I’d guess never. What about internal rotation, e.g. a twist lock? Well there’s a name for that movement, so obviously it’s common! This results in overdeveloped internal rotators, and weak externals. Sorry, I’m getting a little sidetracked. Point of this ramble is, get a theraband and do shoulder exercises. ALL. THE. TIME.
Ok, so if you look at the first picture you can see all the space between the bone and the muscles, specifically above the humurus. This is called the subacromial space (that crooked bone connecting to the clavicle is called the acromion). What fills this space is something called a bursa. A bursa is a fluid filled sack that provides a buffer between, in this case, the acromion and suprasinatus.
With repeated overhead exercise (and/or due to genetic predisposition), the bursa can get squeezed in that space and become irritated and inflamed. For shoulder pain due to rotator cuff weakness, the fix is pretty straightforward: strengthen the weak points, but a bursa is just a sack of fluid. How do you work out fluid?! Maybe Navier or Stokes know, but I don’t. So what is there to do except wait? If you’re following the latest trends, you’ve sworn off anti-inflammatories and icing, but for this issue, icing is key! Now, I’ll admit this is purely anecdotal, but for me icing was an immediate and long lasting fix. The best way I’ve found to ice for this is to use an ice cube. It makes it much easier to pinpoint just the bursa. I’ll usually wrap the back half in a paper towel so I don’t freeze my fingers off and to keep the dripping to a minimum. You’ll want to feel around to find the subacromial space, then just dig that ice cube right in for a few minutes. After that, just try not to aggravate it the rest of the day. By the next day my shoulder is typically completely fine. So if you’ve ruled out a rotator cuff issue, try this little tip and hopefully you’ll get back to crushing in no time!