Trigger thumb is among the many common conditions we treat  treat via occupational therapy and trigger thumb release surgery at Proliance Hand, Wrist and Elbow Physicians. We recently posted an exposé on the world of trigger fingers, so now we are covering trigger thumbs. As with trigger fingers, trigger thumb patients typically experience a click or locking sensation in the afflicted finger or thumb as the hand goes from a grip position to an open palm or vice versa. While the exact cause is not known, trigger digits are thought to be due to overuse or repetitive activities. They can be associated with other conditions, like diabetes or carpal tunnel syndrome, but can also be present by themselves. Trigger fingers and thumbs can be particularly bothersome in the morning as they often become “stuck” overnight.

Why is my thumb clicking and painful?

 The best explanation we have for why trigger digits hurt involves a tunnel that’s too tight for a tendon to easily move through. This too-tight fit manifests itself as pain and a clicking sensation. Our article on trigger fingers discusses this more in depth and you can find it by clicking here. Classically, the mechanical irritation from overuse leads to thickening of the flexor tendon and/or tendon sheath which can be felt in the palm as an area of swelling with a small, moving nodule. With enough friction and a large enough nodule, the finger goes from just painful to painful clicking to painful locking where the finger is no longer able to fully mobilize on its own without using the other hand to force the finger open or closed. The worst trigger fingers and thumbs are those that present completely stuck and are unable mobilize even with an applied gentle force to do so.

What do we know about the treatment of trigger thumbs?

Despite the fact that finger and thumb triggering is one of the most common issues a hand surgeon sees, there are estimates of over 200,000 cases of trigger digits per year, trigger thumbs seem to always get lumped together with fingers and there are limited studies on trigger thumbs alone. Conservative management is very similar to trigger fingers and can include patient observation, splinting, anti-inflammatory medications, and corticosteroid injections.

Much like trigger fingers, the natural history has been studied for trigger thumbs and there are reports of complete symptom resolution at an average of 6.8 months without any particular treatment. The results of splinting, corticosteroid injections, and anti-inflammatory medications were discussed in our series on trigger fingers and most studies do not isolate trigger thumbs alone. Unfortunately, many patients do not see relief with any  conservative management and elect to proceed with trigger thumb release.

When should we perform a trigger thumb release?

Trigger thumb release surgery is currently being researched more deeply as some surgeons are been pursuing a more minimally invasive approach. Much like our trigger finger sheath system, the anatomy of a thumb flexor sheath includes a proximal annular pulley (A1), a variable annular pulley (Av), an oblique pulley, and a distal annular pulley (A2). Generally the pathology of most trigger thumbs involves the A1 pulley and special care is used to preserve the oblique and A2 pullies to prevent complications. The goal of trigger thumb release surgery is to divide the A1 pulley to create more space for the flexor tendon and resolve the pain that occurs with powerful grip. Many studies have shown low rates of recurrence with an open release that can largely be performed under local anesthesia. One study even showed the complete resolution of symptoms after surgery for trigger thumb release on average about 1.5 weeks afterwards as compared to 5.2 weeks for trigger fingers. Recent surgical research has explored performing this trigger finger and thumb release entirely percutaneously, in other words without making an incision, using only a needle to divide the A1 pulley. While the idea to perform the procedure percutaneously is almost 30 years old, the particular anatomy of the digital nerve in relation to the A1 pulley typically causes surgeons to prefer performing the procedure while visualizing the nerve.

While some surgeons still perform and advocate percutaneous trigger thumb releases, there is a well-documented complication of nerve injury of approximately 5.7% with a percutaneous approach to trigger thumb release. The 2020 American Society for Surgery of the Hand president Martin Boyer once wrote a commentary that summarizes the current nature of percutaneous trigger thumb releases: “Percutaneous release adds an unnecessary layer of risk and complexity to a treatment that is straightforward and has withstood the test of time.” So while many surgeons continue to advocate for percutaneous trigger thumb release, it may be that the latest and greatest is not an improvement on the tried and true!

How Can Proliance Hand, Wrist and Elbow Physicians Help?

A consultation with Proliance Hand, Wrist and Elbow Physicians can help determine if your hand suffers from trigger thumbs. Our highly trained occupational therapists are onsite at our Kirkland and Bellevue offices for your convenience to see your hand surgeon and therapist quickly and conveniently. Whether it is time to try a splint or a steroid injection or surgery for your trigger thumb, our staff can help you make an appointment at any of our five convenient Eastside locations.

 



About the Author:

Samuel E. Galle, M.D. is a board-certified orthopedic surgeon with subspecialty fellowship training in conditions of the hand and upper extremity. He has published numerous peer-reviewed articles and surgical technique videos. He lives in Kirkland, WA with his wife, two kids and one especially spoiled Cavalier King Charles Spaniel.