Steroid Injections for Trigger Finger
Trigger finger and trigger thumb (medically known as stenosing tenosynovitis) is the painful clicking of the tendon as it passes through the tiny pulleys at the bottom of the finger. The finger/thumb will get stuck in a bent position and will “snap” when it straightens. There is usually a gradual onset of symptoms and may start with a small painful lump at the base of the finger.
Over time the finger or thumb may get stuck in a flexed position and require strong pressure to extend it.
Symptoms of Trigger Finger
- Finger clicking when going from a flexed position to straight
- Mostly affects thumb, middle finger and ring finger
- Intermittent locking of the finger when it is flexed and requires passive force to straighten it. Patients often describe waking up with the finger bent down towards palm which they have to painfully pull on to straighten. Some people also report their finger locking when grasping something.
- Tender bump at the base of the finger or thumb that may radiate into the palm
Causes of Trigger Finger
Trigger finger can affect people of all ages, but is more likely to develop in peoples fifth or sixth decade (Andreu et al, 2011).
The condition may also be associated with those who perform repetitive finger movements or do lots of gripping, whether it’s related to work (carpenters or gardeners) or leisure activities (rock climbing).
Certain medical conditions such as inflammatory rheumatic diseases, thyroid disorders and diabetes mellitus also increase your risk of developing trigger finger (McAuliffe, 2010).
Generally, the risk of developing trigger finger is 2-3%, however in the diabetic population it rises to 10% (Bianchi et al, 2020).
The flexor tendons are long cord-like structure that attach the forearm muscles to the bones in the fingers. When the muscles contract, the flexor tendons allow the fingers to bend. Each of the tendons are surrounded by a sheath. Along the sheath are bands of tissue called “pulleys” which hold the flexor tendons close to the finger bones. When you bend and straighten your fingers the tendons glide through the pulleys. There are 5 flexor pulleys in each finger and 2 in each thumb.
The pulley at the base of the finger is known as the “A1 pulley” and is near the opening of the tendon sheath. The A1 pulley is most commonly involved in trigger finger.
How to diagnose
At your consultation, one of our highly skilled physiotherapists will ask a series of questions and perform a physical examination to help develop a diagnosis. The assessment will include checking your hand and finger range of movement, strength and flexibility of the limb and commonly an ultrasound scan may be performed to assess for tendon gliding and thickening of the A1 pulley or tendon.
Physiotherapy treatment may include the following:
- Advice on avoiding aggravating activities or modifying activities to reduce inflammation.
- Splinting of the finger to limit range of movement and allow inflammation to settle.
- Specific exercises to help the tendon glide and strengthen the hand
- Ergonomic and postural advice
Anti-inflammatory gels applied to the base of the finger or thumb can be effective in some cases.
Trigger Finger Steroid Injection Therapy
If symptoms have not improved with physiotherapy, or if the pain is affecting your sleep, stopping you from performing everyday activities such as getting dressed or is limiting you from performing your physiotherapy exercises you may want to consider an ultrasound guided steroid injection. Steroid injections have been found to be effective in reducing pain and frequency of symptoms in trigger finger (Yildizgoren et al, 2015).
Steroid injections use a small dose of corticosteroid (a strong anti-inflammatory drug) and are injected under ultrasound-guidance. Current evidence found that injections performed under ultrasound guidance are more accurate and more effective at reducing pain and improving function than landmark guided injections (Daniels et al, 2018).
Recent evidence has found that Extracorporeal Shockwave Therapy (ESWT) is an effective treatment for trigger finger resulting in significant improvements of symptoms (Vahdatpour et al 2020). ESWT will bring new blood vessels into the damaged tendons and healing begins to occur, allowing tendons to glide within their sheath. Shockwave treatment is a great alternative for people who decline to have a steroid injection or are contraindicated.
Andreu, J.L., Oton, T., Silvia-Fernandez, L. and Sanz,J. (2011) Hand pain other than carpal tunnel syndrome (CTS): The role of occupational factors. Best Practice and Research Clinical Rheumatology. 25 (1) pp.31-42.
Bianchi, S., Gitto, S. and Draghi, F. (2020) Ultrasound features of trigger finger: review of the literature. Journal of ultrasound in medicine. 38(12) pp. 3141-3154.
Daniels, E.W., Cole, D., Jacobs, B. and Phillips, S.F. (2018). Existing Evidence on Ultrasound-Guided Injections in Sports Medicine. Los Angeles, CA: SAGE Publications
McAuliffe, K. (2010) Tendon disorders of the hand and wrist. Journal of Hand Surgery. 35 (5) pp.846-853.
Vahdatpour, B., Momeni, F., Tahmasebi, A. and Taheri,P. (2020) The effect of Extracorporeal shockwave therapy in the treatment of patients with trigger finger. Open access journal of sports medicine. 11. pp.85-91.
Yildizgoren, M.T., Velioglu, O. and Hayal, G. (2015) Trigger finger: ultrasound-guided injection with an in-plane approach under the A1 pulley. Therapeutic Advances in Musculoskeletal Disease. 8(2) pp. 51-52.