Insight
Case Studies
February 2, 2023

Electrotherapy as a treatment for trigger finger

Rick Rowan
Published on: 
February 2, 2023
NuroKor Team
Published on: 
February 2, 2023

Electrotherapy as a treatment for trigger finger

Trigger finger is a common condition that affects millions of people worldwide. Although it is usually only painful, trigger finger can develop into a more serious problem that ultimately limits mobility and flexibility in the finger. Treatment for trigger finger can require invasive procedures including surgery, making it a prime candidate for innovations to give patients non-invasive options.

What are the symptoms of trigger finger?

Trigger finger usually starts out as pain at the base of the finger or thumb, and the finger might also click when moved. If not treated, the condition can progress, potentially causing a lump at the base of the finger, difficulty moving the finger and eventually not being able to bend or straighten it.

A man holding their hand

What are the causes of trigger finger?

The root cause of the condition is not fully understood, although there are several factors that can make its occurrence more likely, with women, people over 40, and people with diabetes or rheumatoid arthritis more at risk.

Whatever the root cause is, the symptoms are the result of problems with the body parts that control the movement of your fingers.

Tendons, their normal function, and their role in trigger finger

Central to the movement of your body are the tendons, which are strong tissue connecting the bones in your fingers (and everywhere) to your muscles. The movement of your fingers is controlled by muscles in your palms and forearms - when these contract, it is actually the tendons that then pull on your finger bones and cause the fingers to bend.

To ensure that the tendons move smoothly and freely, they sit in a lubricated tube or sheath. Trigger finger occurs when there is something interfering with this smooth motion. It can be a problem with the tendon itself - perhaps a small lump forms on it that rubs against the sheath - or it can be a problem with the sheath. This latter may take the form of swelling or inflammation, which causes the sheath to press against the tendon.

When the tendon cannot move freely, this is what can lead to the sudden clicking or straightening of the finger.

A diagram showing how a lump on a tendon can restrict movement of the finger
The above diagram shows how a lump on the tendon can prevent free movement

What are the current treatments for trigger finger?

Fortunately, trigger finger can get better by itself, but there is also the chance of it becoming much worse so intervention is advised.

Rest and splinting

The simplest treatment is just to rest the affected finger, a process that can be aided with the use of a splint. This binds the affected finger to another, limiting the ability for them to move while giving support. With rest, the inflammation or swelling in the area may get better by itself and movement can return to normal.

If these approaches do not work, then the next interventions are more invasive. 

Steroid injection

Steroid injections can be used to reduce swelling in the area, hopefully relieving pressure on the sheath and the tendon inside. Steroid injections for trigger finger work in approximately 50-70% of cases, and although they can permanently resolve the issue, there is a chance that it comes back. Furthermore, they’re less effective for people with certain conditions, such as diabetes and rheumatoid arthritis. If trigger finger comes back after the first injection, you can have a second but it is usually less effective.

Surgery

A surgical needle and thread
Surgery for trigger finger is simple but can still require open surgery

Surgery is generally the last resort. There are two versions, both of which are normally done as a simple outpatient procedure. The first involves cutting the sheath around the tendon to then widen it so that the tendon can move more easily. The second does not require an incision, but instead uses a needle to break apart the tissue that is hindering movement of the tendon.

As with any surgical procedure, there is always the possibility of infection, and it may be necessary to undergo some physiotherapy to help the hand and finger recover to full function.

Ultimately, surgery has a high success rate and it is rare for trigger finger to return if treated in this manner.

How electrotherapy can be used to treat trigger finger

Patients and practitioners would prefer to avoid invasive interventions if possible, but aside from rest and splinting the finger, there are limited options for tackling inflammation, which is the most common cause of swelling. One of these is non-steroidal anti-inflammatory drugs (NSAIDs), but they are not suitable for everyone and long-term use can lead to gastrointestinal ulceration and bleeding, kidney toxicity and potential for haemorrhagic stroke.

Electrotherapy, on the other hand, is viable for long-term use due to minimal side effects and has been shown to influence the production of substances in the body that regulate inflammation. 

This is achieved through microcurrent therapy, where therapeutic electrical currents with parameters that mimic the natural bioelectric currents in our bodies are applied to an inflamed or injured area. By influencing the processes involved in inflammation, this therapy has been shown to both support recovery from injuries and manage the risk of inflammation becoming chronic and therefore harmful. If you would like to know more about this, we have a paper on the subject.

A graph of amplitude against time
The appropriate parameters in amplitude and frequency is essential to effective electrotherapy

One of electrotherapy’s great benefits is that it can be used non-invasively. NuroKor’s signature therapeutic electrical technology, for example, is delivered via wearable devices where a conductive glove or pad  is applied to the area that needs treatment. Added to this, our technology can be used in the comfort of your own home, reducing the need for interaction between patients and health care professionals. 

Combine this with the fact that as a drug-free treatment electrotherapy does not have the same severe side effects profile as NSAIDs, and the case for using electrotherapy to treat trigger finger is strong.

Treating trigger finger with electrotherapy - a case study

Singer and songwriter Stan Graham

Folk singer and songwriter Stan Graham suffered from trigger finger, which interfered with his ability to play the guitar and was having a significant impact on his career. As someone who already used NuroKor’s technology for muscle aches and back pain, Stan tried it on his trigger finger as well.

With two 30-minute treatment sessions per day he eased the pain in his fingers and improved their mobility, even finding that the results lasted for several hours. After a few weeks of treatment, Stan’s trigger finger was cured and he can continue to perform at concerts without any concerns.

Read more about Stan’s experience here.

The future of trigger finger treatment

As a condition that is more likely to affect women, people with chronic conditions and older people, trigger finger’s prevalence - currently around 2% of the population - may increase in future as populations become older.

While there are currently a range of effective treatments, the results of all except surgery are not guaranteed. Electrotherapy offers an option for patients to use themselves without a professional’s supervision to resolve problems without drugs or undergoing invasive procedures.

About NuroKor

Founded in 2018, NuroKor is a company committed to the development of bioelectronic technologies. NuroKor develops and formulates programmable bioelectronic software for clinical and therapeutic applications, in a range of easy to use, wearable devices. It provides the highest-quality products, delivering personalised pain relief and recovery support and rehabilitation to patients.