This is an excellent question and we applaud you for not only asking it but also for considering donating your physical body for the sake of study. When properly written, your advance directive and will can reflect your intentions to support research efforts to improve medical procedures.
You may want to consider becoming an organ donor as well — this is the gift of life for some people waiting for critical organs needed just to stay alive. There are many studies published in medical journals based on the use of cadavers (human bodies preserved after death for study). Here’s one that crossed our desks this week. The question was asked:
When is surgery indicated for a rotator cuff tear? That is the focus of a cadaver study from the Orthopaedic Biomechanics Laboratory in California. They started with the hypothesis that there is a critical point at which a rotator cuff tear is large enough to cause abnormal joint biomechanics.
Usually surgery is scheduled when the patient has completed a rehab program and is still experiencing significant pain and loss of motion. If loss of motion (and therefore function) depends on the size of the tear, then what is the critical tear stage that just won’t respond to rehab and requires surgery?
This study was done in order to identify the critical stage when rotator cuff tears will progress to the point of needing surgery. The researchers used a custom-built shoulder testing system to measure the effects of varying loads placed on the muscles of the rotator cuff and parascapular muscles.
They loaded the muscles of eight cadavers under three separate conditions: 1) rotator cuff only, 2) rotator cuff muscles with deltoid muscle, and 3) rotator cuff, deltoid, pectoralis major, and latissimus dorsi muscles. They used the traditional staging for rotator cuff tears based on footprint anatomy (that’s where the muscle inserts on the bone).
Stage I was a tear of the front or anterior portion of the supraspinatus tendon (one of the four tendons of the rotator cuff). Stage II represented a complete tear of the supraspinatus tendon insertion. Stage III was a complete tear of the supraspinatus and half of the infraspinatus (another of the four tendons of the rotator cuff). And finally, Stage IV was defined as a complete tear of both the supraspinatus and infraspinatus tendons.
What did the researchers conclude from this information about the critical stage when surgery is needed for rotator cuff tears? Stage II tears signal a change in shoulder external rotation and abduction. Progression to Stage III and Stage IV result in biomechanical changes in the humeral head in relation to the shoulder socket (also affecting motion).
Rehab early on is still recommended as the first line of treatment. The goal is to prevent progression of the tear while restoring normal shoulder joint kinematics. Strengthening the suprascapular muscles is equally important during conservative care (rehab). By strengthening the pectoralis major, latissimus dorsi, and deltoid muscles, it may be possible to restore normal joint movement, reduce pain, and eliminate the need for surgery.
And with the many active athletes (traumatic tears) and older adults (degenerative tears) with this problem, a study such as this is very important to help direct and guide treatment (conservative versus surgical). Of course, this is only one example but a useful one as it is estimated that 17 million people in the United States alone are affected by rotator cuff disorders. One cadaver can make a difference!