The thumb is commonly strained during falls when you try and break the fall with the palm of your hand and during skiing when you take a spill with your hand strapped in the ski pole. The main ligament that is damaged is the ulna collateral ligament which is responsible for supporting the thumb during pinching and grasping activities.
Sprains are graded I, II, or III, depending on the severity of the sprain:
• Grade I sprain: pain with minimal damage to the ligament
• Grade II sprain: more ligament damage and mild looseness of the joint
• Grade III sprain: complete tearing of the ligament and the joint is very loose or unstable. There may also be fractures.
Symptoms of Thumb strain
• Pain, swelling, and tenderness at the inner part of the base of your thumb
• Decreased or lack of ability to grasp between the thumb and the index finger
• Movement of the thumb causes pain
Diagnosis and treatment
Your doctor or physiotherapist will diagnose this condition. In grade III sprains surgery is required to repair the ligament. Following surgery the thumb will be put in a cast to allow healing to occur. In grade I and II sprains protective splinting or taping will be used by your physiotherapist to allow healing of the ligament to occur. In the early stages electrotherapeutic modalities and gentle soft tissue techniques may be useful in reducing pain and inflammation.
Once adequate healing has occurred your physiotherapist will aim to restore full function of the hand. This would involve reducing any residual pain and swelling and gradually improving full range of motion and strength. It is important to note that other soft tissues may also have been damaged and require treatment. Finally your physiotherapist will guide you in your return to sport and educate you in preventative measures to prevent re-injury.