From the Guidelines
Immobilizing the thumb is most effectively achieved through the use of orthoses, specifically a custom-made thermoplast long orthosis to be worn during activities of daily living, as recommended by the 2019 EULAR update 1. This approach is supported by recent evidence showing beneficial effects of orthoses on pain and function in patients with thumb base osteoarthritis, particularly when used for a prolonged period of at least 3 months. The choice of immobilization method depends on the severity of injury and treatment goals, with options including:
- Custom-made thermoplast long orthosis for thumb base osteoarthritis
- Prefabricated orthoses for less severe cases
- Buddy taping for minor sprains
- Athletic tape for temporary immobilization
- Compression gloves with thumb stabilizers for moderate support These immobilization techniques work by limiting motion at the carpometacarpal, metacarpophalangeal, and interphalangeal joints, allowing injured ligaments and tendons to heal properly. It is essential to pay attention to prescribing a well-fitted orthosis, preferably custom-made by a specialized health professional, to improve patients' compliance and increase long-term use, as noted in the 2019 EULAR update 1 and supported by earlier recommendations 1.
From the Research
Immobilization Techniques for the Thumb
There are several ways to immobilize the thumb, including:
- Using a thumb spica splint, which can be effective for treating thumb carpometacarpal osteoarthritis and de Quervain tenosynovitis, as well as for patients with suspected scaphoid fractures 2
- Utilizing a forearm-based thumb-spica cast or splint, which can be used for immobilization after surgery or for acute injuries 3, 4
- Applying a custom-molded thumb CMC immobilization splint, which can prevent motion of the first metacarpal and allow unrestricted thumb metacarpal and wrist joint motion 5
- Using supplemental transarticular MP Kirschner wire fixation in addition to a forearm-based thumb spica splint, which can provide more effective protection for the ulnar collateral ligament during immobilization 6
Duration of Immobilization
The optimal duration of immobilization for the thumb is still a topic of debate, with some studies suggesting that shorter immobilization periods may be just as effective as longer ones:
- A study comparing shorter (3-5 days) and longer (10-14 days) immobilization periods after surgery for thumb carpometacarpal osteoarthritis found no significant differences in pain or hand function outcomes between the two groups 4
- Another study found that a conservative immobilization protocol did not improve functional outcomes or satisfaction compared to an early mobilization protocol after ligament reconstruction and tendon interposition surgery 3
Key Considerations
When immobilizing the thumb, it's essential to consider the following factors:
- The type and severity of the injury or condition being treated
- The individual patient's needs and compliance level
- The potential risks and benefits of different immobilization techniques and durations
- The importance of proper fitting and construction of any immobilization device to ensure accurate positioning and well-distributed pressure 5