You’ve never handled a gun in your life, yet you’re being told you have a trigger finger? What is that? Something Clint Eastwood has?

No, it’s nothing so glamorous as Hollywood. If your finger gets stiff or stuck when bent and you get a painful snapping feeling when you straighten it, this may be “triggering”.

Think of your fingers as a complex pulley system. Each finger has long flexor tendons that come from your forearm, via the wrist. These glide freely through tunnels called tendon sheaths and each time the finger moves, the flexor tendon glides through this tunnel like a finely-tuned machine. The sheath contains lubricating fluid and the glide should be smooth and free of obstruction. Along the sheath are pulleys, which hold the tendon against the bone as they move.

Sometimes the flexor sheath and the pulleys can become irritated and inflamed, obstructing the tendon as it moves through this tunnel. When there is obstruction, there can be increased inflammation and scar formation. This makes the sheath even tighter with the result that the tendon can get trapped there and the finger is unable to straighten. A bit of a vicious cycle.

As opposed to a condition like Dupuytren’s disease, a trigger finger involves the tendon and tendon sheath directly.

Trigger finger is more common in women between 40 and 60. The condition can begin after periods of extensive hand use and can sometimes happen to more than one finger. Symptoms include swelling, a tender lump on the palm of your hand, pain and/or difficulty straightening your fingers. Many people report that they wake up in the morning with the finger stuck in a flexed position into the palm which requires them to actually pull the finger out straight again. Diagnosis is usually by clinical examination rather than a test. There are a couple of tricks to this which your hand surgeon will be able to work out.

Initial treatment is usually a steroid injection and some hand therapy. If this does not settle the problem within 6 weeks you may need an operation.

Surgery can usually be performed under local anaesthetic as a day case in hospital. The surgeon will make a small incision on the palm of your hand at the base of the finger that is ‘triggering’. They will then release the problematic pulley that is stopping the tendon from gliding.

You will go home that day with your hand bandaged so someone will need to drive you home from hospital. Recovery usually involves some scar management and therapy to restore range of motion and normal function. Sometimes the scar can be a bit sensitive for a while but most people recovery quickly.