“Reducing strain during everyday activities” 

Turning a key in a lock is usually not a problem. But it is one of many challenges for patients suffering from osteoarthritis of the first carpometacarpal joint. Prof. Dr. med. Stefan Sell, Medical Director of Surgical Medicine at the hospitals in Neuenbürg and Mühlacker/Germany, which belong to the Enzkreis group of hospitals, believes that this condition is the most uncomfortable type of osteoarthritis in the area of the hand. He is advocates early functional treatment with relieving thumb braces, like the new RhizoLoc OA, for which he supervised the wearing test. 

life: What makes treating osteoarthritis of the first carpometacarpal joint so challenging?

Prof. Sell: Almost every hand movement, whether trying to hold a mug, pen or cell phone, requires the thumb. Precise grasping movements, such as the inferior pincer grasp and the regular pincer grasp, where the index finger or the other fingers and the thumb meet from opposing directions, are movements that have paved the way for the evolutionary advancement of humans. The carpometacarpal joint of the thumb plays a significant role in this. As soon as osteoarthritis develops in this area, it can barely be avoided during everyday activities. You will feel it immediately when you turn the key in your front-door lock. In many ways, osteoarthritis of the first carpometacarpal joint is the most uncomfortable type of osteoarthritis in the hand. Everything you do hurts. The more you do, the more the pain will increase. Of course, you can use the other hand, but the movement will be less coordinated, take more time and be less effective. The ability to work will be significantly restricted. What is urgently needed in these cases is a treatment concept that precisely and functionally supports those affected in their everyday activities and necessary tasks.  

When should the thumb joint be functionally supported?

Prof. Sell: Osteoarthritis of the first carpometacarpal joint is one type of osteoarthritis that is noticed quite early on, one reason being that it restricts the patient quite quickly. As with other, usually large joints, early treatment measures, such as occupational therapy or physiotherapy, are useful. The two frequently conflicting paradigms of osteoarthritis treatment – a lot of activity, little strain – must always be weighed. The following applies in any case: eliminating extreme strain in the workplace and at home. In the beginning, the joint can still be moved freely. But when osteoarthritis progresses, the joint’s function may be restricted because of changes in the soft tissue known as adduction contracture. In the inferior carpal area, the joint is still firm, but in the metacarpal area above, the unstable metacarpophalangeal joint splays because it tries to overcompensate. This is visually noticeable right away. I’d prefer not to see this stage again. Because that means there are two damaged joints. The first restriction in mobility is caused by pain. This is followed by the second one with the contracture, which causes restriction, and then we’ve arrived at the final stage of osteoarthritis. Of course, we want to start treatment much, much earlier. My progressive approach is: yes, the patient can continue to work, but phases of strain have to be reduced and movement peaks prevented. This is where I see the perfect opportunity for thumb braces. Pain during movement is a clear indication for a stabilizing brace. Using it when the patient hurts during rest is much too late in my opinion, also with regard to the progression of the condition as well. I’d like to use braces at an early stage of osteoarthritis of the first carpometacarpal joint to eliminate the highest possible percentage of strain.

What did the wearing test with the new RhizoLoc OA show?

We have said it many times before, but it bears repeating: the best brace, or more accurately, the brace with the best intention, cannot help when it sits in the drawer. The development of a slim, adjustable thumb brace is the obvious answer. The RhizoLoc OA is unobtrusive and fits securely and comfortably during movement. An essential prerequisite for compliance is the quality of the materials used. When we look at who develops osteoarthritis of the first carpometacarpal joint, we can see that women are at the top of the list. Women still do the majority of the housework, where contact with water cannot be avoided. Now, the question is: do I have to take off the brace or not – ten or twenty times per day? Where should I put it, where will I find it again? These practical questions that are crucial for compliance were solved with the selection of materials that can be wiped dry. So the answer is: don’t take it off, just briefly release the thumb strap. This solution is also relevant for treatment. An effective thumb brace should be providing constant support, not just every now and then. In order for the patient to be able to perform grasping movements under strain again, the RhizoLoc OA immobilizes the carpometacarpal joint and the metacarpophalangeal joint of the thumb and supports the strength from the interphalangeal joint of the thumb. The relieving extension is supported and guided by the brace, pressure in the carpometacarpal joint is reduced and diverted via the brace.

“The RhizoLoc OA provides immobilization,
stabilization and functional support.
It allows patients to return to everyday activities.”

Prof. Dr. Stefan Sell

What options does surgical treatment offer?

Prof. Sell: In surgical treatment, we practice a stage-dependent approach. In cases of severe pain at an early stage, denervation is an option. But we only get very few patients for this because conservative treatment, as is the case in other areas as well, provides better options now. If the joint is destroyed, there are two options. The first is suspension arthroplasty, i.e. a bridge construction suspended on a tendon on which the proximal phalanx of the thumb can move. The second option is thumb carpometacarpal prosthetic joint replacement. A prosthetic joint replacement is carried out in exceptional cases only. By default, we would choose suspension arthroplasty. After surgery, all patients will receive a stabilizing brace for the first six weeks as follow-up treatment to compensate for the loosened contracture and therefore allow for a return to original movement patterns. However, patients must realize that pain will reduce relatively quickly after this procedure, but it may take about six months for the thumb to regain its full basic strength. This prolonged duration is based on the surgical procedure: the cavity created by removing the bone is filled with the suspensionplasty. The patient then has to wait for the ingrowth to be completed before functional stability is completely restored.

This provides an excellent case for early conservative treatment of the thumb.

Prof. Sell: For all types of osteoarthritis, non-surgical treatment has become more significant over the last few years. It is of particular importance for osteoarthritis of the first carpometacarpal joint. We will perform surgery only if all measures within conservative treatment, with stabilizing braces as the central element, have been fully exhausted. A wearing test with the new RhizoLoc OA has proven its possibilities. In addition to a reduction in pain, patients report a good level of wearing comfort in their evaluations. This is heavily dependent on the orthopedic adjustability. The brace can be adapted to the size of the palm and the wrist circumference. It can easily and quickly be put on and closed with one hand. All these are features that are needed to increase compliance, which is often underestimated. The wearing test was carried out with patients who are subjected to a normal level of strain. Construction workers who have to carry around 50 kg bags probably need something else. But even in this category, I would start with the RhizoLoc OA and observe if they need to move to the next level. For moderate strain in everyday life, during leisure time as well as at work, a brace like the RhizoLoc OA is a pleasant solution that serves the required purpose: it provides immobilization, stabilization and functional support. It allows patients to return to everyday activities.

Relieving extension during grasping movements

The immobilizing RhizoLoc OA brace relieves the painful carpometacarpal joint and metacarpophalangeal joint of the thumb in cases of osteoarthritis, arthritis as well as after injuries or surgery. An anatomically contoured plastic brace as well as an innovative, narrow strap system immobilize the thumb down to the interphalangeal joint and keep the thumb and index finger in a defined position. This makes grasping movements possible and the base of the thumb is guided in relieving extension. The stabilizing effect of the brace is designed to help alleviate pain and provide support during everyday activities as well as functional treatment measures. The new RhizoLoc OA is pleasantly lightweight and particularly suitable for everyday use, thanks to its material, comfort and hygiene features. Patients can put on the lightweight brace with one hand and secure the strap via a clip. A thumb strap made of soft, self-engaging Velcro velour provides additional support and protects clothing and surfaces. The textile wrap can simply be released to wash hands or cleaning dishes.  

In Germany, the RhizoLoc OA is listed in the Medical Aids Directory provided by the German statutory health insurance funds under the medical aid number 23.07.01.1065. 

Easy handling with one hand

Carpal degeneration

The first carpometacarpal joint can also be affected by osteoarthritis. This joint is made up of the first metacarpal bone and the trapezium of the carpus. The carpometacarpal joint of the thumb allows flexion and extension, adduction and abduction as well as rotation of the thumb. That is why it can be positioned opposite the fingers to grasp objects (pincer grasp). The thumb has its own adductor muscle (adductor pollicis) that moves the thumb in relation to the palm of the hand.

Osteoarthritis of the first carpometacarpal joint develops ten to fifteen times more often in women than in men. It is the most common type of osteoarthritis of the hand, but compared to the large joints, such as hip and knee, it occurs much less frequently. The incidence is generally increasing for all types of osteoarthritis. In cases of osteoarthritis of the first carpometacarpal joint, the condition is usually found in both hands. Mechanics, sewing specialists or chefs, who predominantly hold their thumb in the pincer grasp, are affected more often than those doing heavy physical labor. Strain is not always the main cause. Genetic factors are also being discussed. People who are right-handed often complain about problems in the left hand. There may also be rubbing sounds. Pain when grasping objects, such as lifting a water bottle, is a typical early symptom. The thumb’s mobility is usually not restricted despite increasing joint misalignment. Pain and stiffening, however, will gradually reduce load-bearing capacity and compensatory options. Over time, osteoarthritis of the first carpometacarpal joint will lead to a visible deformation of the thumb joint. 

Risk factors:

• Female
• Middle to advanced age
• Menopause
• Predisposition
• Obesity, high blood pressure 
• Ligament lesions and fractures of the thumb 
• Occupational strain on the thumb 

Images: Bauerfeind