Not to put too fine a point on it, but the thumb is part of the hand. Hooked onto the hand by a complicated little saddle joint and a fair amount of tissue, it is a hard worker at lunch grabbing and other functional issues requiring grasping.
I first paid real attention to the thumb and the parts holding it on and moving it in a class at Boston University which covered the 600-ish human body muscles and their origins and attachments. The final exam featured the teacher, her assistant, and a table with all 600-ish of the muscles on file cards spread out face down. One chose 6 cards, turned them over, and for one’s whole final grade one regurgitated the origin and attachments of the 6 muscles.
This one luckily turned over 6 thumb muscles, one after another. The teacher looked at me with pity and said, “Go ahead and put 4 back and pick some others if you want.” I smiled bravely and said, “Oh no, these are the ones I chose, and I will do them.” Then I rattled off the answers, to her shock.
Here’s how that “rattling off” happened: not 5 minutes before that my study group went over all the thumb muscles, in our last desperate attempt to know everything. My “rattling off” felt so cool, reinforcing the oft-told adage of my father that it is better to be lucky than good, if you have to choose.
Now, years into my practice, that information is still graven in my brain. It comes with the whole megillah, the table, the teachers, and the exultance.
Here are some things I have learned since that time.
Make sure the small bones of the hand, the metacarpals, are not jammed up and misplaced. They can really cause the thumb to not ride smoothly in the saddle joint. The techniques for doing this can vary, depending on the tissue and the amount of jamming. Often the trapezoid, trapezium, and scaphoid bones are frozen and misplaced, held in those places by the soft tissue so that the thumb cannot ride easily in the misplaced saddle. Others of the small bones can be jammed, too, and often are. The whole thing needs to be restored to function.
Here’s one picture you get when you Google: hand structure. This will clearly show you what all is involved in support for the thumb.
When working with hands, I begin by horizontalizing the tissues, including the thumb. Basically horizontalizing the tissues is to take the strain out of them. Then working gently and carefully I tease the bones apart, having them find their more appropriate homes through the process. I might take the bones together and then apart, so there is a gentle unwinding. I might do a gentle pulling apart. I might use some gentle “muscle energy” techniques to get the nerve signals to the muscles to reset. It depends on how the hand is tied up.
Of course, as you see on the internet, there can be arthritis in the joints which complicate these procedures. Unless the joint is really chewed up and macerated with all the cartilage gone, these procedures can help.
The thumb is like a door in a frame; if the frame is good, the door has a chance to swing freely with all of the functions available to it.
Don’t stretch the thumb. You have little chance of doing it the right way for your thumb issues. Though maybe you will get lucky, too. (lol)