Updated: Feb 4
In my 15+ year career as a hand therapist, I have worked with a multitude of patients with trigger fingers and trigger thumbs. I have helped many patients resolve their symptoms with typical hand therapy treatments of splinting and stretching. However, some patients would struggle with ongoing or reoccurring symptoms. After 2-3 months of conservative treatment, I would refer them back to a doctor for a corticosteroid injection. Some patients with severe unrelenting cases have needed to undergo a surgical release.
I have wondered what the conditions are for those who develop trigger digits and what I else I could do as a hand therapist. When reading about trigger finger, I would often encounter quotes like this: “Several causes of trigger finger have been proposed, though the precise etiology has not been elucidated.” (1) In most of the medical books & journals I’ve read and hand therapy courses that I’ve taken, the focus has typically been on the biomechanical causes of trigger finger and the relationship of trigger finger occurring with other conditions, such as diabetes. Until more recently, I did not find much written (or researched) about the impact of nutrition on trigger finger.
In my studies about Nutritional Therapy, I have learned how dietary habits and nutritional deficiencies can impact common inflammatory hand conditions, like tendinitis, carpal tunnel syndrome, and trigger finger/thumb. It is my personal quest to educate my patients and clients, fellow hand therapists and other health professionals about the important role of nutrition in conjunction with traditional hand therapy. My purpose of this blog post is to describe the incidence, etiology, and presentation of trigger finger and then focus on hand therapy treatments and the nutritional issues that can impact the development and resolution of trigger finger.
Trigger finger/thumb is one of the most common causes of hand pain in adults. The reported prevalence is 2-3 % of the general population and most often appears in the middle 5th and 6th decades of life (2). It occurs up to 6 times more frequently in women (1). The risk of developing trigger finger increases up to 10% in diabetics. There also appears to be a higher risk in patients with carpal tunnel syndrome, de Quervain’s disease (thumb abductor tendinitis), hypothyroidism, rheumatoid arthritis, renal disease and amyloidosis (abnormal proteins deposited into organs and tissues). The ring finger is most commonly affected, followed by the thumb (1). The long, index and small fingers can also be affected and some people develop multiple trigger digits.
Trigger finger earns its name from the painful popping or clicking sound when the involved digit is bent and straightened. It was first described in 1850 by Notta (1). Proposed causes are repetitive finger movements and local trauma to the base of the finger/thumb. There are reports linking trigger finger to occupations that require extensive gripping and finger flexion, such as the use of shears or hand held tools. However, this relationship is questioned, with studies finding no association between trigger finger and the workplace. “In reality the causes of trigger finger are multiple and in each individual often multifactorial” (1).
The biomechanical explanation of trigger finger is that is created from a difference in the diameter of a flexor tendon and it's retinacular sheath. The sheath is a fibrous tube that contains a pulley system to keep the tendons close to the finger bones. The symptoms of trigger finger may begin as painless clicking with finger motion. Further development can cause painful catching or popping and progress into the finger “locking” up. A painful nodule (firm bump) may be felt at the base of the finger on the palm side. The nodule is a thickened area that typically occurs where the finger flexor tendons enter the sheath and glide under the A1 ligament. Each finger and thumb have a flexor pulley system made up of a series of fibrous bands called annular ligaments and cruciate pulleys (as well as an oblique pulley in the thumb). These bands keep the tendons gliding close to the bones to prevent “bowstringing”, which is likened to trying to reel in a fish on a fishing pole with no eyelets. The first A1 ligament, located at the base of each finger ad thumb, receives the most friction with digit motion. With repetitive stress the ligament can become inflamed. The body then thickens the pulley with tough connective tissue to "strengthen" it and better withstand the compression stress (4). However, this becomes a problem because the increased thickness puts pressure on the tendons which, in turn, can develop a thickened lump as they try to adapt to the increased stress. This creates a negative feedback loop with both the A1 pulley and the flexor tendon(s) growing thicker. This is why Trigger Finger/Thumb is also called Stenosing Tenosynovitis. The "trigger" occurs when the tendon lump begins to catch on the thickened pulley. As you can see in the simplified image below, the lump gets stuck on one side of the pulley and can become locked into flexion or extension. Getting stuck in flexion (after bending the finger/thumb) is most commonly seen.
Some patients notice a feeling of stiffness and then a progressive loss of full flexion or extension without ever developing the catching and locking of a “typical” trigger finger. Some patients report stiffness or swelling in the morning or that they wake up with the digit locked and then it loosens during the day. Initially, the locking can be released with active extension in an attempt to straighten the finger. It is important to note that the flexors of the hand are 3-4 times stronger than the extensors, which is why, overtime, the finger can lock up so firmly that it requires a manual release from the other hand. Since this manipulation is very painful, patients tend to try to avoid the triggering and reduce that finger's motion, which then creates secondary stiffness in the middle knuckle of the finger (a PIP joint contracture) .
HAND THERAPY TREATMENT
Working for many years as a Certified Hand Therapist, the treatments that I commonly provide for trigger finger and trigger thumb are as follows:
1) Passive finger exercises, using the other hand, to move the affected finger into full flexion and extension in order to decrease stiffness and prevent joint contractures. If the finger remains relaxed, it can be moved by the other hand without catching because the tendon inside is not being pulled by an active muscle contraction. I also teach specific stretches for the intrinsic hand muscles (the dorsal and volar interossei and lumbrical muscles).
2) Stretching the long extrinsic flexor muscles of the fingers (located in the forearm) to decrease tightness.
3) "Ring" splinting to limit full flexion (bending tip into palm) during the day to prevent catching/locking.
4) Night extension splinting to keep the middle knuckle of the finger straight at night.
Patients who are persistent with these treatments and avoid catching/locking for 6-8 weeks have the best outcomes, however, all hand therapists know that trigger fingers often reoccur. I now believe that this is likely due to underlying nutritional issues not being addressed. Providing education about proper hydration and nutrition, along with traditional treatments, can be effective in reducing and preventing reoccurrence of trigger finger and thumb.
NUTRITIONAL ISSUES TO ADDRESS
1) Dehydration: There is increasing evidence that even mild dehydration plays a role in the development of chronic diseases (3). To learn the ideal amount to drink for your body weight, please read my first blog post titled the #1 Ingredient for Healthy & Flexible Joints: https://www.holistichandhealth.com/blog-1
2) Lack of Magnesium: Magnesium is a mineral that helps muscles relax and allows the body to utilize calcium optimally. It was surprising to learn that 50% of Americans are deficient in magnesium and this which worsens with age as evidenced in 80% of the elderly. Lack of magnesium causes muscles to get tight and stay tight. Supplementing with Magnesium Glycinate, Mag L-Threonate or Magnesium Citrate can be helpful. A standard dosage of 250-300 mg before bed is recommended, however, some people may need higher doses. It is important to note that the citrate/carbonate form (found in a powdered supplement called Natural Calm) has a laxative effect. As a Nutritional Therapist, I tailor the dosage and form of Magnesium to fit each client’s needs.
3) Lack of Vitamin B6: B6 vitamin is involved in over 150 enzyme reactions in the body. It directly impacts the body's ability to utilize magnesium, which means supplementing with magnesium alone is often not enough. A B6 deficiency is linked to increased pain perception and since the body/mind doesn’t like pain, it will react in ways to try to reduce pain = a thickened A1 ligament = which paradoxically causes more pain.
Supplementation of activated B6 (P5P ) at 20-50 mg, 3 times daily, is recommended (5). It is important to choose a supplement with activated P-5-P form of B6, which stands for Pyridoxal-5-Phosphate. I recommend my patients with trigger finger/thumbs to take activated B6 for 2-3 months. It can take up to 6 weeks to notice a effect.
4) Avoid Yellow Dye No. 5 and Tartrazine Derivatives
"Yellow Dye No. 5 and Tartrazine inhibit B6 metabolism, which leads to the deficiency that can cause trigger finger. Yellow dye # 5 can be found in soft drinks, certain beverages, baked goods, breakfast cereals, processed vegetables, chips, pickles, honey, mustard, gelatin desserts, pudding, ready to use frostings, dessert powders, candy, gums, cosmetics, and in certain medicines and other foods." (6)
5) Lack of Vitamin B12: When it comes to B12 supplementation, there is a wide range of recommended dosage. I hesitate to recommend a specific dosage without an individual evaluation. Patients can boost the amount of vitamin B12 in their diets by eating more meat (beef), fish (salmon and cod), eggs and dairy products (if lactose tolerant).
6) Gluten Intolerance: This is a HUGE player in many chronic health conditions. Gluten intolerance creates Leaky Gut, nutritional deficiencies and inflammation. Gluten intolerance in a major factor in Rheumatoid Arthritis and other auto-immune conditions that affect the joints. There are many methods for testing gluten intolerance but currently there is no “gold standard”. A simple blood test can screen people for celiac disease but they must be currently eating a diet that includes gluten for it to be accurate. You can learn more about gluten intolerance/allergy testing options in this Healthline article:
7) Lack of Vitamin D: People living in northern/southern latitudes that area more than 37 degrees from the equator are at high risk for Vitamin D deficiency. It is very common and most people are unaware of it. The symptoms are often subtle and non-specific, but they can include muscle weakness/aches/cramps, pain, fatigue and depression. A general guideline for supplementation is to take the D3 form at 2000 IUs during the summer and 5000 IUs during the winter. However, it is important to have vitamin D levels checked once a year with dosages tailored to each client’s current level.
8) High sugar/carb diet: Modern research has repeatedly shown that high sugar diets create inflammation in the body, which is an underlying cause of diabetes, obesity and many other chronic health conditions. I encourage my patients/clients to cut out soda and other sugary drinks, including fruit juice as it’s much better to eat the whole piece of fruit. I also advise everyone to decrease their consumption of processed/packaged foods, which often contain High Fructose Corn Syrup and poor quality oils/fats. I stress the importance of eating enough high-quality protein and healthy fats. I have written about these topics in other blog posts to support my patients/clients and other health professionals.
I enjoy working with individual patients & clients as a OT Hand Therapist and Nutritional Therapist to blend traditional and holistic therapies. I have learned the importance of addressing the root nutritional issues behind symptoms and conditions. I provide comprehensive evaluations and treatment plans with tailored recommendations. I approach each person as a unique bio-individual and include both dietary and lifestyle encouragement. The next time you hear of someone complaining of a trigger finger or thumb, please send them this blog post and refer them to me for a holistic consultation. I appreciate your support!
1) Makkouk, A, Oetgen, M, Swigart C, Dodds, S. Trigger finger: etiology, evaluation, and treatment. Cur Rev Musculoskelet Med. 2008 Jun; 1(2): 92-96. Published online 2007 Nov 27. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2684207/
2) Blazar P.E., Aggarwal, R. Trigger finger (Stenosing Flexor Tenosynovitis). 2019. UpToDate. com https://www.uptodate.com/contents/trigger-finger-stenosing-flexor-tenosynovitis
3) Manz F, Wentz A. The importance of good hydration for the prevention of chronic diseases. Nutr Rev. 2005; 63(6 Pt 2): S2-S5.
4) Tucker, J. The Trigger Thumb Tendonitis Dynamic. 2018. Tendonitisexpert.com https://www.tendonitisexpert.com/trigger-thumb.html
5) Dach, J. Vitamin B6, Pyridoxine for Trigger Finger and Carpal Tunnel. 2014. Drdach.com http://www.drdach.com/Vitamin_B6_TriggerFinger.html