Make a Splint for Your Sore Thumb Joint

Arthritis of the joint at the base of the thumb is one of the most common types of arthritis in the hand. The joint is called the carpometacarpal (CMC) joint. A splint worn to support the joint is one of the best things for dealing with this problem, preventing pain and more soreness in the joint. This splint, or brace, can be made easily and inexpensively. It is machine washable and dryable (low heat). One of its most important features is that it can be worn under gloves. The Velcro attachment is on the palm part of your hand where there is a hollow area to accommodate the bulk under the gloves, and the back of the hand has just a thin strap where there is less room under the gloves.

How I got here

I am a dentist, and have had this problem for about twenty years. I at first thought that I might have to give up my profession and my hobbies because I had so much pain. I have seen four physicians, two of them were hand specialists, and also two physical therapists about this problem. They asked me “Do you ever do any pinching movements with your fingers and thumb?” I said “Yes, all day every day in both my work and my hobbies”. Age makes you more likely to get this, and so does activity that stresses the joint.

The best thing that happened to me was using a splint to support the joint. The problem is not curable without surgery. Surgery involves wearing a cast for six weeks, further recovery that may take as long as a year, possible shortening of the thumb, and it may only last 15 years. I have been happily doing what I want for twenty years. Yes, it is still sore, but it is nothing I can’t deal with. There are other things that can be done as well (more on this later). I do many things to help my joint, and have done them since my problem started. But my problem started with the right hand, and I did everything except the splint for both hands, and only wore the splint on my right hand. Five years ago my left hand started with the problem. I made a splint for my left hand, and within two months my left hand had improved to the same level as my right hand.

When you pinch something with your thumb and fingers, it causes the base of the thumb to slide out away from the base of your hand, which aggravates the joint. The splint supports the thumb joint, and prevents it from sliding out at the base. Then it can hinge at the joint without the pain-inducing sliding.

There are a number of splints available online, and others that can be made by a physical therapist. These are great, but I had some requirements that these did not handle.

1. I needed it to be worn under rubber gloves, without being too bulky. Splints with rigid parts pinch against the hand from the tension of the rubber glove.

2. It must be machine washable. During a long appointment on a warm day, my hands perspire, and the splint is wet at the end of the appointment. It is nice to have a dry, clean one to replace it.

3. If it is inexpensive, I can make a bunch of them. Some are for work, and some are for my workshop at home. It is easy to change to another if one becomes dirty or wet.

All of these materials can be obtained at your fabric store or from amazon.com.

1. Knit nylon fabric. It must be stretchy. I chose beige color so that it would look less visible. Use a material that won’t fray at the edges.

2. Elastic 1 ½ inches wide. Dritz 1 ½ inch Soft Waistband Elastic 9577W is perfect. There are some elastics that are thicker, which work but have more tension than is needed, are bulkier, and are more challenge to sew.

3. Elastic ¾ inch wide. Dritz Ribbed Non-Roll Elastic 9301W

4. Velcro 1 ½ inches wide.

First print the pattern. I chose to print it on heavy paper. I punched holes where I wanted to mark important places on the materials. I printed separate patterns for the right and left hands. You can use the same pattern and flip it over for the other hand, but is easy to forget that everything needs to be reversed, and mistakes in positioning the parts are easier to happen.

I have made patterns for three different sizes: small, medium, and large. I have tested the small and medium, and have not tested the large. The patterns can also be made smaller or larger by choosing to print it scaled to a different size. Only two dimensions are really important for the size: the length of the elastic circling the thumb and the distance between the top border on the thumb and the bottom border below the thumb joint. The strap can adjust to different sizes, and the Velcro gets sewn on in a position that fits your hand. The tightness of the thumb circle can also be adjusted by where you sew it closed.

I have made a chart showing the dimensions of some of the pieces. The elastic strap and its sheath may be a little long for some hands, but these can be trimmed shorter when you try the splint on and before you sew on the strap’s Velcro. You might need them even longer for larger hands.

This project requires only straight and zigzag stitches, with mostly zigzag because it will stretch. I have noted the stitch width, stitch length, and thread tension. If the width is zero, then it is a straight stitch. The tension is a guideline, and your sewing machine may be different than mine. If a stitch says “4W,2L,9T”, then it is a zigzag 4 mm wide, stitch length of 2 mm, and a tension of 9. Most stitches are locked at the beginning and end going about 5 stitches forward, reverse, and forward. I apologize for using inches and mm in different places, but my materials are in the U.S. system, and the sewing machine reads out in mm.

Begin by sewing the rectangular sheath that covers the strap: pin it to the width of the elastic strap, sew it 4.5W,1.4L,9T. Lock it at one end. At the other end stop ½ inch from the end without locking it. This end may be trimmed when the splint is almost done, and may be trimmed shorter to fit your hand at that time. Cut off the excess near the stitching, and turn it inside out.

Sew darts in the outer cover of the strap. These will make the splint curve around the base of the thumb. Make sure that the material that is sticking out is on the inside of the splint, toward your hand. The excess material will be covered up by the elastic.

Sew the darts in the elastic of the strap: straight stitch 0W,2.5L,8T. This time the material sticking out is toward the outside of the splint, away from your hand, where it will be covered up by the outer cover of the splint. Then, cut the folded out triangle of material close to the stitches, and run a zigzag stitch over the seam 4W,1.2L,9T. This will reinforce and flatten the strap in the reshaped spots, and will make it smoother where it lies against your thumb.

Next, sew the thumb elastic onto the cover 4W,2L,9T. There is line on the pattern for the bottom edge of the thumb elastic. The cover wraps over the elastic and ¼ inch is tucked under the elastic. If you are going to make splints for both hands, sew this with matching thread for one hand, and use a different color thread for the other hand. Then it is easy to spot which splint is for which hand. Pin it first in the center, then pull the material at the ends of the thumb elastic to get it around and follow the curve. Then sew it.

Then hem the side seams only at the top 1 to 1 ½ inches, folding it over twice and sewing 4W,2L,9T. If you do this now, it will be easier to manage the fabric when sewing the lower part of these seams.

First, put the strap cover over the elastic, with the stitches facing the inside of the strap in the center. Then sew it to the elastic going across the strap, ¾ inch from the top of the dart for a medium splint, and ½ inch from the dart for a small splint, 4W,1.6L,9T.

Next, pin the strap to the cover, lining up the bottom edge of the strap with the line shown on the pattern. Then, roll the bottom of the cover over two times to make a hem at the bottom, and pin it in place. Don’t sew it yet. Turn the splint over and roll the side of the splint near the strap under to make a hem and pin it. You already sewed the upper inch or so. This hem and the bottom hem meet at the lower edge of the strap. Sew the side seam from the outside of the splint, then turn it over and sew the bottom seam 4W,2L,9T.

Now on the palm side, pin and then sew the side seam and the flap of the cover that goes over the palm.

Next, sew the fuzzy Velcro onto the palm. This piece of Velcro will be longer than the hooked Velcro on the strap, to give a range of area that the strap can be fastened. I recommend sewing it straight stitch 0W,2.5L,8T once around plus one more edge to lock it, and use a slightly different color of thread. This will make it easier to find and rip this someday to replace the Velcro. Also, after a period of time the stretchiness of the strap may weaken a little, and it is useful to trim the strap shorter and reposition the Velcro to tighten it up a little. The rest of the splint lasts longer than the Velcro, so replacing the Velcro at some point can add new life to the splint. These splints last for years through frequent use.

With the splint inside out, sew the thumb elastic together at the ends so that it forms a loop to go around your thumb. Sew it close to the ends so that the loop is a little big.

Now put the splint on and make sure the tightness of the short elastic around the thumb is a good fit. Sew another line across the elastic to make the loop smaller if needed. Try it on again to determine the length of the strap that goes around the back of your hand. Trim the elastic strap and sew the strap cover to the strap so that the end of the elastic is covered: straight stitch 0W,2.5L,8T. Sew the hook part of the Velcro onto the strap. The strap does not need to be super tight. It just needs enough pressure to help support the joint.

It is done! Wear it when you are engaged in activities that stress the joint. It is great for wearing during medical activities under latex gloves. It would be useful under golf gloves or other gloves, and of course without gloves as well. Wearing it shows some improvement in a few days, but over a period of weeks the thumb joint can recover and reduce in inflammation leading to much more improvement.

This is not intended to be professional advice, but is what I have learned from the physicians and physical therapists that I have seen for treatment. I think numbers 1 to 4 are the best.

1. Exercise the joint. This is done by rotating the thumb in as wide of a circle as you can, 10 or 20 times every day. The arthritis causes roughness to build up on the bone, which makes the joint even more painful. The exercising wears down these rough spots, which reduces the pain. When my problem started, I was trying to protect the joint and not move it as much. The exercises hurt at first, but as the joint loosens up, it all hurts less. A physical therapist gave me additional exercises to do, but the rotations seemed to do it for me just fine.

2. Your fingers are more efficient than your thumb, so if you can do something with your fingers instead of your thumb it will help protect your thumb joint. Lifting a stack of plates with your thumb on top and fingers underneath is a big stress on your thumb joint. Lifting them with two hands and your fingers under the plates protects the thumb. Use your fingers and palm to squeeze pliers instead of your thumb and fingers.

3. Use tools that protect your joint. If you write a lot with a pen or pencil, use a fat one with a cushion grip that gives better grip. Your thumb is happier gripping a larger diameter. There are silicone cushion grips that slip over skinny hand instruments, and make holding them easier on your thumb. Wet them with alcohol to slide them on more easily. They come in different sizes to fit pens, hand instruments, and even dental handpieces, and can survive sterilization.

4. Glucosamine, or Glucosamine/Chondroitin dietary supplements: There is controversy on this, since there does not seem to be hard scientific evidence that this works on everyone. For many, it seems to do nothing much until you have taken it for a few months. A friend told me: “Take it for two months and they won’t be able to take it away from you.” I believe it really helps, and have talked to many who agree. I take one 500 mg. tablet twice a day. This is not a drug, but a dietary supplement, but you should consult your physician to make sure it doesn’t interact with other medications or medical problems you may have. Another friend of mine was told by a veterinarian to give it to her dog. She said it made a noticeable difference in her dog’s pain and activity. It is unlikely that it is placebo effect if it worked on a dog.

5. Change your gloves. If you use latex or other gloves, consider a looser size. Gloves pull on your thumb joint, and stress the joint further. If you are using “ambidextrous” gloves (made for either hand), consider changing to “handed” gloves (right and left gloves have the thumb facing in a more natural direction).

6. Cortisone injections: I got an injection that miraculously “cured” the problem for months. A second injection later worked about half as well. Later injections seemed to do nothing at all. Others have had similar results. It may work for you, but I think it wasn’t worth the trouble.

7. Pain medications: Medications like Ibuprofen, Aspirin, Celebrex and others do help, if your body can take these. I could take them for a while, but then my stomach had problems. Long term taking of some medications is hard on your liver, and can interact with other medications or alcohol. Pain ointments did not help that much. I decided it was time to “cowboy up”, get tough, and not take pain medications. This problem does not go away, and a long term strategy without pain medications is better. The splint gave me far better results and it is kinder to my body.

8. Heat: Applying heat to the joint is supposed to help. There are hot wax baths, where you dip your hand in the wax, cool, and re-dip until you have a thick layer of wax on your hand. The wax holds its heat, and keeps your hand warm for a longer period of time. I thought that this was a lot of trouble, didn’t seem to help so much, and I got such good results with numbers 1-5 that I feel it wasn’t that useful.

The above things can help, but I think the splint made the largest difference of all. I hope this helps you.

Check my website at www.chaneyproductions.com to see other crazy things I have made.