Trigger Fingers. Causes, symptoms and current treatment

Trigger fingers, also known as stenosing flexor tenosynovitis, are relatively common in the general population, which means that a large number of people are affected. For this reason, correct treatment (conservative or surgical) is essential to restore the functional capacity of these patients.

What a trigger finger is?

It is an impairment of the flexor tendons of the fingers as they pass through one of the pulleys in this area. Specifically, there is a discrepancy in space between the flexor tendon and the A1 pulley.

Pulleys of the fingers

This constant friction produced between the two structures, will cause a thickening and irritation of the tissue, which will give the classic symptomatology to the patient.

Symptoms of trigger finger

This condition in the flexor tendon will cause clicking, trapping or blocking, which can be painful. Normally the patient is able to reverse this blockage, although in advanced stages it may be impossible and a surgery release is required.

Palpable and painful nodules may appear at the palm level, which may exacerbate the symptoms when palpated at the A1 pulley level.

These patients often report problems with grasping and holding objects or manipulating small objects such as buttons or coins.

Causes and aetiology

Among the causes that can cause its appearance:

1.Repetitive gestures of bending the fingers and grasping vigorous objects.
2.Discrepancy in size between the A1 Pulley and the flexor tendon due to a thickening of the tendon or the pulley itself.

Several authors have observed incidence data of 2-3% in the general population, the value of which may increase in the presence of certain comorbidities such as diabetes mellitus or inflammatory arthropathies. It has also been shown to be more prevalent in women than in men.

It is common to find its appearance in combination with the presence of carpal tunnel syndrome, Dequervain’s tenosynovitis and Dupuytren’s disease.

Although its name is associated with inflammation (“-itis”), the evidence has observed the opposite. An example is this study by Lundin et al (2012), which performed a histological analysis of the tissue. Their results showed the absence of inflammatory cells or synoviocytes. Thus, these authors propose the use of the term “Flexor Tenovaginosis” for this pathology.

Diagnosis. How to detect a Trigger finger

The diagnosis is purely clinical, in other words, we will base it on the symptoms and the clinical history that we can carry out with the patient, paying attention to the presence of symptoms such as clicks, blockages or painful “triggering “of the finger.

It is interesting that, in advanced cases, the rest of the fingers of the hand are assessed, as they usually present a certain affectation.

We leave you with this classification of severity of Quinnell’s grading system for trigger fingers:

Trigger finger treatment

According to the 2014 HANDGUIDE clinical guide, in which the results of a systematic review and the opinion of expert hand surgeons and hand therapists were obtained, it was concluded that the treatment to be carried out will depend on the severity of the symptoms, the time of the symptoms and the patient himself.

Here you can access a pdf of treatment choice table from the clinical guide, which you can use in your practice.

Among the proposed treatments we find the use of Orthoses. There are several works that highlight the beneficial effects of this therapy on Trigger fingers. It seems that those that limit and block the Metacarpophalangeal joint (MCF) are more effective than those of proximal interphalangeal blocking (DIP). However, the choice of the type of orthosis will depend on the reasoning of the therapist, the preferences of the patient and the activities he or she is used to doing.

Orthosis example for MCP joint

The period of wear may last between 3-12 weeks, the average in published scientific studies being 6 months. The only time patients are allowed to rest from it is for cleaning or for finger mobility exercises.

These orthoses are usually accompanied by exercise programmes to avoid stiffness, maintain ROM and muscle mass, and promote resolution of the problem.

Other proposed treatments

Other techniques proposed in the guide are corticosteroid injections, corticosteroid injections together with orthoses or surgery. Because infiltrations have been shown to be a short term solution and related to relapses, surgery is usually proposed as a management of permanent resolution of symptoms.

When the symptomatology is advanced and has been maintained for more than 2 months, surgical management of the finger is proposed. This is usually performed with a small transverse incision at the level of the Pulley A1 under local anaesthesia, in order to release the area.

It is imperative that after surgery, active rehabilitation is carried out as early as possible, through progressive therapeutic exercise, to avoid possible post-surgical complications such as scar adhesions, and to promote early recovery.

Here is an example of a patient doing her exercise programme with ReHand app on her tablet. As the patient manages her symptoms, she progresses in mobility and strength.

Post-Surgery exercises with ReHand app on a tablet

ReHand app will allow post-operative exercises to be performed either at home or face-to-face, with evidence-based exercises and sensory-motor control.

Pablo Rodríguez Sánchez-Laulhé

Physiotherapist and Health Researcher

References

Colbourn, J., Heath, N., Manary, S., & Pacifico, D. (2008). Effectiveness of Splinting for the Treatment of Trigger Finger. Journal of Hand Therapy, 21(4), 336-343. https://doi.org/10.1197/j.jht.2008.05.001


Ferrara, P. E., Codazza, S., Cerulli, S., Maccauro, G., Ferriero, G., & Ronconi, G. (2020). Physical modalities for the conservative treatment of wrist and hand’s tenosynovitis: a systematic review. Seminars in Arthritis and Rheumatism, 50(6), 1280-1290. https://doi.org/10.1016/j.semarthrit.2020.08.006

Giugale, J. M., & Fowler, J. R. (2015).Trigger Finger: Adult and Pediatric Treatment Strategies. Orthopedic Clinics of North America, 46(4), 561-569. https://doi.org/10.1016/j.ocl.2015.06.014


Huisstede, B. M., Gladdines, S., Randsdorp, M. S., & Koes, B. W. (2018). Effectiveness of Conservative, Surgical, and Postsurgical Interventions for Trigger Finger, Dupuytren Disease, and De Quervain Disease: A Systematic Review. Archives of Physical Medicine and Rehabilitation, 99(8), 1635-1649.e21. https://doi.org/10.1016/j.apmr.2017.07.014


Lunsford, D., Valdes, K., & Hengy, S. (2017). Conservative management of trigger finger: A systematic review. Journal of Hand Therapy. https://doi.org/10.1016/j.jht.2017.10.016