Trigger Finger

REQUIREMENTS: consent, povidone-iodine, spirit, a needle of 16-18G and one needle of 25G, 3 ml syringe 

PROCEDURE: 

• Prepare the site in a sterile fashion with povidone-iodine solution

 

• Using a 16- or 18-gauge needle attached to the 3-mL syringe, draw up a combination of 0.5 mL of lidocaine and 0.25 mL of corticosteroid (either triamcinolone or betamethasone)

 

• Change to a 25-gauge needle

 

• Place the needle in the midline of the finger, through the finger flexion crease at the junction of the finger and hand, and angle it approximately 50° proximally, with the bevel of the needle facing proximally

 

• This places the needle distal to the A1 pulley in the hand and is far easier than inserting the needle right at the A1 pulley. Generally, there is much less tenderness distal to the lesion at the A1 pulley

 

• Advance the needle through both flexor tendons until it contacts bone. Slowly withdraw the needle, with forward pressure on the barrel of the syringe, until the resistance encountered by the needle is decreased, indicating that the needle is within the flexor sheath

 

• This injection should not require any force, and the solution should be quite easily injected into the flexor sheath

 

(With a 25-gauge needle, injection into the flexor tendon (as opposed to the flexor sheath) requires a very large amount of force. Thus, if the flexor sheath injection seems to require a great deal of force, it is likely that the needle is positioned inappropriately in the flexor tendon) 

 

• The provider often visualizes or palpates the tendon sheath filling during injection to confirm that the needle is placed well within the sheath

 

 • When the injection is complete, withdraw the needle slowly from the sheath, and place an adhesive bandage over the injection site

 

• The provider should warn the patient that he or she may note pressure in the finger during this step. Also, warn the patient that the area injected is likely to be tender and painful for a day or two. In addition, remind the patient that steroids take some time to have effect; often, patients wait 3-5 days to experience a difference in clinical symptoms

 

• Subcutaneous injections for trigger finger have also been described and have been shown to have effect. If the injectate escapes the sheath and subcutaneous fluid is seen, the injection may still have effect

TIPS & TRICKS: 

• Palpate the flexor sheath and mark the line with your thumb nail

• Get the patient to flex their fingers in and out if you are having trouble

• Clean with alcohol swab then no touch technique

• If the needle goes too deep it will hit the flexor tendon

• Do not injure the neurovascular bundle present on either sides of the flexor tendon

• Never inject against resistance

• Ask patient to gently move their fingers while injecting. If the syringe moves with movement of finger, it indicates that needle is in the flexor tendon

COMPLICATIONS: 

1. (Most common ) Recurrence of the triggering of the finger

2. Infection at injection site 

3. Flexor tendon rupture after corticosteroid injection 

 

VIDEO LINK: https://youtu.be/0VSxtk1oQ2s   

Written by our guest author Rishabh Rawat

Illustrations by Anveshi Nayan
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