A trigger finger is a very common and treatable problem. It can occur in both fingers and the thumbs, which have tendons that help them to bend. The flexor tendons that bend the fingers have a lining on the outside. This lining is called tenosynovium. The tendon and lining are covered by a series of thick, soft tissue called pulleys. The tendon and its lining are designed to glide through the pulleys without friction. The pulleys are similar to how a line is held on a fishing rod (Figure 1).
A trigger finger, sometimes referred to as a trigger thumb or stenosing tenosynovitis, can occur if one of three things happen: 1. The tendon enlarges (does not fit through pulley well); 2. The lining increases in thickness (does not fit through pulley well); 3. the pulley becomes thicker (the opening for the tendon gets smaller). The finger tendon and pulley system is designed to have the exact right sizes of each structure. The change in size of any of the important finger structures can cause problems. If the tendon becomes tight within the pulley, the lining gets squeezed and reacts with thickening. The bigger lining then produces more fluid. And the higher volume of fluid increases pressure. The undersurface of the pulley can also change and thicken. This thicker pulley causes friction on the moving tendon. This makes it difficult for the tendon to move back and forth (Figure 2).
The good news is that trigger finger can be diagnosed by the history, symptoms, and a physical exam. It is rare to require other diagnostic testing. It is also helpful to know this problem has several very successful treatments.
Some symptoms of trigger finger can include:
The goal of treatment in a trigger finger is to reduce or eliminate the swelling and catching/locking, allowing full, painless movement of the finger or thumb. The ability to restore the finger to what the patient believes is normal or 100% is easier when the problem is diagnosed and treated as soon as possible.
Common treatment options include, but are not limited to:
If non-surgical treatments do not relieve the symptoms, surgery may be recommended. The goal of surgery is to open the pulley at the base of the finger so that the tendon can glide more freely. The clicking or popping goes away in most cases after cutting the A1 pulley. If there are still mechanical symptoms after a trigger finger release, a flexor tenosynovectomy can be considered. This procedure removes the thickened lining from the surface of the tendons. If there are still mechanical symptoms, then part of the superficial tendon can be removed to reduce the volume of tendon moving in and out of the rest of the pulley system. It is optimal if all the above surgical treatments can be performed during the same procedure.
With surgical treatment, the chances of recognizing and treating all changes to the finger is improved when it is possible for the patient to be awake at the end of the procedure to follow instructions. By having the patient able to actively bend and straighten their fingers several times, the surgeon can verify the mechanical symptoms are absent. Finger motion can return at different speeds depending on each patient and their unique timing of symptom development, when treatments begin, and the effectiveness of each type of treatment. Your orthopaedic hand surgeon will develop an individual treatment plan for you. There are different ways to perform the surgery. There are several different surgical techniques, anesthesia options, and locations where the procedure can occur.
There can be some ongoing stiffness after hand surgery even if there is no more locking, and it may remain long-term. Therefore, hand therapy can be beneficial after surgery whether or not it was used before surgery. There may be some mild to moderate tenderness at the surgery area for up to several months after surgery. However, most patients resume their normal lifestyles within a few weeks.
Learn more about common conditions of the hand and upper extremity, including carpal tunnel syndrome and de Quervain’s tenosynovitis, by browsing the full list of diseases and conditions on HandCare.
© 2020 American Society for Surgery of the Hand
This content is written, edited and updated by hand surgeon members of the American Society for Surgery of the Hand. Find a hand surgeon near you.