Trigger finger or stenosing tenosynovitis occurs when the finger gets stuck in a bent position. The affected finger may straighten in a snap, similar to a trigger being pulled and released. The condition develops when the space within the sheath (surrounding the tendon) becomes narrow (stenosis) because of inflammation.
In severe cases, the finger can become locked in a bent position. Individuals whose hobbies and job involve repetitive gripping or sports like golf are more prone to developing the condition. Trigger finger is also observed to be more common among women and those individuals with diabetes. Treatment for trigger finger will vary and will depend on the condition’s severity.
Some of the most prevalent symptoms of the condition include:
- Tender lump (in the palm)
- Popping, clicking or catching sensation (in the thumb joints or finger)
- Swelling in the affected finger
- Pain (when straightening or bending the finger)
- Finger gets locked in a bent position
Catching and stiffness may get worse after inactivity and is often more noticeable in the mornings. Trigger finger often affects the ring and middle fingers and the thumb. It is possible for more than one finger to be affected at a time. In some cases, the fingers in both hands may be affected. Triggering is sometimes more obvious in the morning, when straightening the finger, or when grasping an object firmly.
Diagnosing the condition will not require elaborate testing. The diagnosis is usually based on the physical exam and the patient’s history. During the examination, the patient will be asked to open and close the hand so areas of pain, evidence of locking, and motion smoothness can be evaluated. The doctor will also check if there is a lump present. Lumps associated with trigger finger will move as the finger moves because it is attached to the tendon that moves the finger.
Treatment intervention for trigger finger will depend on how long the patient has had the condition and its severity. Some of trigger finger treatment options may include:
Splinting – Strapping the affected thumb or finger to a plastic splint has been known to help ease the symptoms since it helps prevent the finger from moving. If the finger is locked in the morning, using a straight splint overnight will help. The GP will give advice on how long the splint should be worn. In rare cases, trigger thumb occurs in infants. Parents are taught to stretch the tendon regularly rather than splint the joint.
Corticosteroid Injections – Corticosteroids are given to help minimize swelling and help allow the tendon to move again. Nowadays it is delivered in smaller doses more accurately with ultrasound guidance. In trigger finger, liquid corticosteroids will be injected into the tendon sheath. The effect may be experienced within a few days after the injection but in most cases, it can be felt in a few weeks. Corticosteroid injections are considered effective in approximately 50 to 80 per cent of patients with trigger finger. However, corticosteroid injections are deemed less effective in those with other underlying health conditions like rheumatoid arthritis and diabetes.
Surgery – Trigger finger surgery might be recommended if other conventional options are unsuitable or do not provide much-needed relief. The procedure will involve splitting the affected section of the tendon sheath in a longitudinal way so the tendon can glide freely again. In addition, other key considerations are also taken into account—the severity of the pain, how the condition impacts the patient’s quality of life, and whether trigger finger is associated with other medical conditions—before surgery will be recommended. Oftentimes, trigger finger is considered a nuisance as opposed to a serious condition. However, without proper treatment, the affected thumb or finger may become stuck in a bent (or straightened) position permanently and can make carrying out everyday tasks challenging. Surgery is often carried out as an outpatient procedure and under local anaesthetic. There are 2 types of trigger finger surgery:
1. Open trigger finger release surgery: In open trigger finger release surgery, a small incision will be made in the palm of the hand. Then the surgeon will carefully cut through the tendon sheath in order to make it wider.
2. Percutaneous trigger finger release surgery: Percutaneous means “through the skin”. However, rather than making the incision in the palm, a needle is inserted into the affected finger’s base to get to the tendon. This can also be done under ultrasound guidance.
After the surgery, the patient should be able to move the finger right away. The dressing is often removed after a few days. Ideally, full movement is restored in a week or two. For those who have undergone open hand surgery, the palm can feel sore after surgery but the discomfort should subside in two weeks.
If the finger is stiff prior to surgery, specialized hand therapy might be required after the procedure to loosen it. This may include occupation therapy* or physiotherapy**.
*An occupational therapist can provide practical support and guidance for patients who struggle with routine tasks and activities at home or at work. Occupational therapists also fabricate splints.
**To help enhance hand function and movement, a physiotherapist will use manipulation and massage and teach exercises.