Trigger Finger Release (Stenosing Tenosynovitis) Guide

What is Trigger Finger?

Trigger finger or trigger thumb, when the thumb is affected, can be painful and troublesome in everyday life. This condition is also known as stenosing tenosynovitis. It primarily affects patients in their dominant hand’s ring finger and thumb, but it can happen to any finger or thumb. It is caused by the finger tendon catching on a small ligament in the hand that is there to hold the tendon in place. This ligament is called the A1 Pulley and is shaped like a tunnel.

Symptoms

Patients usually find symptoms worse in the morning due to the long period of inactivity.
In mild symptoms, patients typically describe:

• A small amount of pain in the base of the affected finger or thumb (this can often be the first symptom patients notice)
• Some ‘jarring’ or ‘catching’ when bending and straightening the finger can also be painful and stiff.
  • When the finger is bent, it can straighten very quickly.
• A clicking sensation in the finger when bending and straightening

In severe symptoms:

• The above symptoms become more pronounced and frequent
• A small painful swelling called a nodule can form in the base of the affected finger or thumb
• The finger can lock completely
  • The other hand may be needed to straighten or bend it (common after grasping something for a long time)
• Inability to bend or straighten finger fully

Trigger finger in-depth

Fingers and thumbs have flexor tendons inside them to help them bend. These tendons connect to muscles in the forearm, which control the movement. To help keep the tendon in place, small ligaments attached to the bones form tunnels over the tendon. These tunnels are called Pulleys. To help the tendon slide smoothly through the tunnels, they are covered by a protective and lubricating membrane called the tendon sheath.

In trigger finger, the tendon sheath or the tendon itself becomes inflamed, and a small nodule forms in the base of the finger. When bending and straightening the finger, the nodule gets caught on one of these tunnels causing all the symptoms. Although there are several tunnels, the only one that affects patients is in the base of the affected finger or thumb, the A1 Pulley. The nodule is found very close to the Pulley.

What can cause trigger finger?

It is not fully understood how trigger finger forms, but there are risk factors:

• Being a woman
• Being between 40 and 60 years old
• Having previous hand surgery
• Repetitive and forceful hand movements over a long period of time

Medical conditions, typically causing inflammation, also increase the likelihood that trigger finger will occur:

• Rheumatoid arthritis
  • This autoimmune condition causes inflammation of synovium membranes around the joints. The synovium and the tendon sheath that coats the tendon are very similar.
• Gout
  • An arthritic disease where an excess of a body salt called uric acid deposits itself in joints. It is rare for this to cause trigger finger.
• Amyloidosis
  • Abnormal build-up of a protein called amyloid might deposit in the finger tendons, causing inflammation.
• Diabetes mellitus, type 1 and 2
  • The increase in glucose levels can cause structural changes and damage.
• Hypothyroidism
  • The exact mechanism is unknown, but there is a known link to trigger finger. Correction of the low thyroid levels will often improve symptoms within a few months.
• Carpal tunnel syndrome
  • A hand condition in which a nerve in the hand becomes compressed, causing nerve pain and inflammation.
• De Quervain's tendinosis
  • A hand condition similar to trigger finger, but different tendons only in the thumb are affected.

Goals of trigger finger release

• Cut and divide the A1 Pulley (the ligament the finger tendon is catching on)
• Relieve or greatly improve all symptoms

Cutting through the tunnel (A1 Pulley) prevents the nodule in the hand from squeezing through and getting stuck. This allows the tendon to glide through smoothly again when bending and straightening the finger. Being able to restore full function can depend on how limited finger movement was before surgery. It cannot be guaranteed to restore function fully, especially if full straightening of the finger wasn’t possible.

The other tunnels (pulleys) in the finger hold the tendon in place, so dividing the A1 Pulley rarely causes structural problems.

Cost of Trigger finger release

Broadly, the price of surgery with a private orthopaedic surgeon is between £1500 and £2500. Prices can change depending on pre-existing health conditions, the surgeon's expertise and which highly rated CQC hospital the procedure takes place.

After the consultation with the surgeon, patients will be given a customised price for their surgery.

The surgery is elective, and it is the patient’s decision if they feel their symptoms warrant surgical treatment. For many patients, trigger finger will go away on its own. GPs will recommend avoiding activities that bring on the pain and encourage resting the affected hand as much as possible. If this is unsuccessful or if symptoms are severe or long-standing, it’s common to try other non-surgical methods. These include:

• Wearing a splint (particularly at night)
• Anti-inflammatory medication (NSAIDs)
• Gentle hand exercises
• Corticosteroid injection(s).

Corticosteroid injections reduce inflammation and are usually the last step of non-surgical treatments For many patients, one injection is enough to improve symptoms. If the pain returns after a second injection, a GP will likely refer to an orthopaedic surgeon for surgery.

If the symptoms are severe, then patients may be treated by an orthopaedic surgeon without trying non-surgical treatments to avoid long-term complications.

The procedure

There are two techniques used to cut the A1 Pulley. The medical name for this surgery is tenolysis, but it is commonly referred to as trigger finger release or sometimes trigger thumb release for the thumb.

Both procedures are performed as day-case surgeries, lasting around 10 to 20 minutes. This means you will be able to go home on the same day as your surgery.

A local anaesthetic is injected into the hand near the nodule. If more than one finger is affected, then more local anaesthetic can be injected into each area. A tight bandage or cuff may be wrapped around the upper arm to reduce blood flow to the hand to help reduce bleeding.

Open trigger finger release surgery

A small cut is made in the palm near the base of the trigger finger. When possible, the surgeon will make this in a natural crease in the palm to help avoid a noticeable scar. The surgeon will expose the affected nodule, tendon, and the A1 pulley (the offending tunnel over the tendon). The surgeon will likely bend and straighten the finger to see the tendon ‘catching’ on the tunnel. The pulley is then cut with a scalpel or surgical scissors. Once the surgeon is satisfied, they will close the opening with stitches, dress the wound, and wrap a bandage around the hand.

Percutaneous trigger finger release surgery

A small needle is inserted into the base of the affected finger or further down the palm. The surgeon then guides it to the A1 pulley and cuts it. This technique is not as common as open surgery because it’s considered riskier. This is most likely because the nerves and arteries in the hand are clearer during open surgery. Despite this, research is showing that percutaneous surgery is a safe alternative to open surgery. An orthopaedic surgeon would discuss the option best for each patient.

What happens in consultation with an orthopaedic surgeon

In the consultation, the surgeon will ask patients to describe their symptoms, and the surgeon physically assesses the affected hand(s).

Usually, scans are unnecessary before surgery as clinical examination and patient history are enough to diagnose and perform surgery. But for some patients, it may be recommended to have an ultrasound or x-ray to check for other structural problems.

Risks and complications

Trigger finger release surgery is a minor surgery, but there are risks and complications for patients to consider, as with all surgeries.

The more commonly seen complications:

• Stiffness in the finger
• Unable to straighten the finger fully
  • If this wasn’t possible before surgery, it might not be possible afterwards.
• Localised pain following surgery for a few days

Rare complications:

• Infection
• Nerve injury
  • If a nerve is injured during the surgery, the finger may have a numb or tingling sensation.
• Bowstringing
  • The tendon may ‘bow’ away from the finger, causing an inability to bend the finger fully and be able to grip properly.
• Complex Regional Pain Syndrome (CRPS)
  • A rare and poorly understood condition that causes localised pain following an injury. It usually resolves itself after a few months but can persist.
• Persistent jarring and clicking when bending the finger
  • Further surgery may be needed to correct this
• Scar tenderness

Aftercare

Some general points on aftercare are summarised in the bullet points below, and a more in-depth look can be found following that.

• Finger movement is encouraged immediately after surgery.
• Follow-up appointment around 10 to 14 days to remove stitches (if not dissolvable)
• Return to light desk work the day after surgery
• Return to manual work for up to four weeks

Recovery

Following surgery, patients will go home with a dressing on the wound and a bandage wrapped around the hand. These will most likely be able to be removed after a few days. It’s important not to get these wet, but showering and bathing will be possible as long the hand can be kept dry.

If there are stitches (and they are not dissolvable), an appointment with a nurse will be made to remove them around 10 to 14 days after surgery. Information on how to care for the wound will be given before discharge, but it usually involves washing hands with warm water and mild soap.

Surgeons encourage most patients to start moving their fingers immediately following surgery, and patients will be given a hand exercise program to follow. The local anaesthetic wears off after a few hours, and there will be localised pain for a few days to a couple of weeks. Simple pain relief, like paracetamol, is usually recommended. To help reduce swelling, raising the affected hand above the heart is encouraged.

Returning to work

Time off work depends on the type of work carried out. Many patients are able to use a computer, write and even perform some light manual work once the local anaesthetic has worn off. The surgeon may be able to write a sick note for a few days if the patient prefers. In manual jobs, up to four weeks off work may be needed.

Driving and sports

Patients are advised not to drive until they feel confident with their hand, which may be a few days after surgery or even earlier. Car insurance companies often have their own time frames on how long patients need to take off from driving after hand surgery and so it is helpful to check with them before surgery.

Getting back into sports depends on the activity but usually, waiting a couple to three weeks is recommended. It depends on how well the hand can grip and how healed the wound is.
For patients that have percutaneous surgery, the recovery will likely be shorter as there is no wound.

Final results

Although patients recover relatively quickly, it may take up to four to six months for swelling and stiffness to completely subside and for the finger to gain full mobility. If it was not possible before surgery, the full movement might not return. Some patients may need hand therapy if the hand stiffness is significant.

All of the information found on our website is sourced from highly reputable experts, and government-approved authorities and is widely used by healthcare professionals.

• https://www.assh.org/handcare
• https://publicdocuments.sth.nhs.uk/pil3461.pdf
• https://www.nhs.uk/conditions/trigger-finger/causes/
• https://orthoinfo.aaos.org/en/diseases--conditions/trigger-finger/

Our content is written by our Medical Quality Managers and Patient Care Advisers, all of who have medical backgrounds and training. Before publishing, all the information is reviewed by a surgeon specialised in the relevant field.