Fig.1Trigger Finger and Trigger Thumb
What is Trigger Finger?
Trigger finger is the symptom of locking of a finger or thumb in the bent position. Often you will be able to straighten the finger with a click without help. Sometimes people need to use the other hand to straighten out the finger. Sometimes these symptoms are worse early in the morning and get better as the day goes on. There may be discomfort at the base of the finger or sometimes on the back of the knuckle.
The problem is caused by a tight tunnel or sheath at the base of the finger, in the hand. One of the finger tendons (guiders) forms a knob, which catches in the mouth of the sheath as it goes in and out. A bit like a wide train carriage going through a narrow tunnel. When the knob comes out of the sheath, the finger locks in the bent position. When the knob goes back into the tight sheath with a click, the finger straightens out.
The operation to release a trigger finger involves making a small cut in the skin of the palm and cutting open the mouth of the sheath to allow the tendon to move more easily. The knob is left in the tendon as removing it might cause the tendon to snap in two. Trigger thumb is very similar to trigger finger. The operation is similar but the cut is at the base of the thumb.
The Trigger Finger Release Operation
After your surgeon has recommended an operation to help your trigger finger, you will be placed on a waiting list for surgery. The vast majority of these operations are done under a local anaesthetic (a numbing injection) with you awake. It is also usually done as a day case operation. That means you will normally only have to be in the hospital for half a day and not over night. You will need a responsible adult to pick you up after your surgery and do not drive to the hospital yourself. Rarely, people are admitted to the hospital over night. This is usually planned before the surgery and is for medical or social reasons.
You will be given a gown to wear on the ward before the operation is carried out. It is recommended that you wash your hands with soap and water before the operation. Make sure your nails are clean. You will be taken to the anaesthetic room, just off the operating theatre, where your surgeon will give you the local anaesthetic injection. This will be where the intended cut will be made. It will feel like a bee sting initially. The injection does not numb your whole hand, only the bit where the operation is to take place. It is normal to feel some pushing during surgery but you should not feel any pain.
You will then have a tourniquet placed around your upper arm. This is blown up when the operation starts so that the wound does not bleed and the surgeon can see what he is doing. It will feel tight around the top of your arm. The surgery only takes around 10 minutes, after which time the tourniquet will be released and you will feel bad pins and needles in your hand. This will only last a few minutes and is due to the tourniquet.
After the Operation
You will find that there is a bandage on your hand. It is important to move your fingers and thumb after the operation to stop them stiffening. Remove the bandage after 2-3 days to allow better movement but keep the stitches covered and dry. They will be removed 10-14 days after the surgery and you will be asked to start massaging the scar with a moisturiser. You may get back to driving after the stitches are out and can consider going back to work.
Risks of Surgery
Generally, this procedure is considered to be very effective and low risk. However some people may have problems. The commonest problem is a little swelling and stiffness of the treated finger for a couple of weeks. This will settle, particularly if you keep the hand elevated and keep the fingers moving. Occasionally there may be more widespread swelling and stiffness of the hand, which if severe is called reflex sympathetic dystrophy and is rare. Occasionally the scar may be tender or a little thick. This is usually temporary and is helped by scar massage. Infection is also rare. Rarely the symptoms return after a period of time and occasionally they to not completely disappear after the surgery. Very rarely the small nerves or arteries on either side of the tendon may be damaged by the surgery. This would cause an area of numbness on one side of the finger.
Do not forget that you will not be able to use the hand that has been operated on fully for a short while after surgery. Make life easy for yourself at home by planning ahead, particularly if you are alone at home or if you will be alone at home for long periods in the day. Get enough shopping in to last for a week or two after your surgery, as you will not be able to drive. Loosen the tight caps of jars (but don’t forget the contents will go off more quickly). Ready-meals might be useful for a few days after surgery or do some cooking before and freeze it. Wear slip-on shoes so you don’t have to tie laces etc.