Instability - Specifically in the thumb saddle joint (CMC -I)

The saddle joint of the thumb is highly mobile, allowing the thumb to move in various directions. Because the joint has relatively weak ligaments and a loose joint capsule, it can easily become unstable. As a result, the thumb may frequently dislocate. In severe cases, the instability may prevent you from properly gripping objects. The pain is typically located beneath the base of the thumb.

Cause of instability in the thumb saddle joint

Thumb saddle joint instability usually results from congenital ligament laxity, dislocation of the thumb base, or trauma involving the joints.
During examination, the degree of instability is assessed, as well as the presence of any joint wear or degeneration.

Treatment of thumb saddle joint instability

Splinting the thumb is not a permanent solution, as prolonged use can lead to muscle weakness and increased instability. However, a splint can be helpful temporarily, such as after a dislocation or in preparation for surgery. During surgery, a new ligament is created using a portion of your flexor or extensor tendon. This graft is pulled through a drilled hole in the bone and attached to the extensor tendon. The result is a newly formed, sturdy ligament that helps hold the thumb saddle joint in place.

Aftercare for thumb saddle joint instability

As with any surgery, complications such as bleeding, tissue damage, anaesthesia-related issues, thrombosis, wound infection, or pneumonia can occur. Fortunately, these complications are rare and can usually be treated effectively. In some cases, the reconstructed ligament may be too loose and continue to cause complaints. After wearing a cast splint for approximately three weeks, you will receive a removable splint from a therapist. You may also opt to use a brace to support rehabilitation and help prevent complications. At Podobrace, we offer a wide range of thumb braces that can provide support for this condition.