This is a ligament injury involving the thumb. It is also called Gamekeeper's thumb. Although the injury can happen by a number of ways but classically it occurs while skiing when thumb is bent backwards causing the Ulnar collateral ligament to rupture or sometime a small piece of bone is pulled off by the ligament.
Sypmtoms and Signs
The injury causes pain around the middle joint of the thumb particularly on the side of the index finger. There is swelling and bruising and inability to use the thumb. Examination reveals tenderness on the side of the thumb where the ligament is ruptured. There may be a small lump which often suggests that the ligament may not heal unless surgical repair is carried out. On stressing the joint the thumb can be moved sideways much more than is normally possible.
An x-ray may show a small fracture on the side of the thumb.
When ligament rupture is partial, a splint may be used for a period of 4 weeks and then exercise is encouraged and gradually increased. Most complete ruptures are also treated in plaster cast and splint if they are not displaced or turned over (Stener Lesion). When examination reveals a lump, this means that the ligament is displaced and repair is necessary. In doubtful cases, an ultrasound may be required to show the type of rupture.
If non surgical treatment is decided then a plaster cast for 4 weeks and followed by a splint for a further 2 weeks is used. Regular examination and checks are done to make sure that healing is progressing satisfactorily.
Surgical repair is best done in the first 2-3 weeks. The ligament is repaired using an anchor. A plaster cast is applied after repair and followed by a splint and after 4 weeks, gentle bending is allowed which is gradually increased.
Chronic Ligament Rupture
If several months have passed since ligament injury then the thumb may remain painful after activity and there is weakness when attempting to grip or hold a key firmly between thumb and index finger. Examination confirms that the ligament is deficient and operation may be required.
The result of late operation is not as good and requires use of a tendon as a graft to reinforce the damaged ligament.
In very long standing cases where there may be evidence of some arthritis in the joint, the best operation is fusion of the MCP joint of the thumb. This will get rid of the ache and pain and strength is restored. Function of the thumb, despite the loss of some movement, is excellent.
FRCS (Trauma & Orth)
Consultant Trauma and Hand Surgeon