Injection Results in Diabetics with Trigger Finger
Stenosing tenosynovitis, or trigger finger, is fairly common among adults. The name is taken from the position of the hand and fingers that result, like that of getting ready to pull a gun trigger. Unfortunately, treatment for trigger finger doesn't guarantee that it won't come back and many people find themselves with the problem again later on. The authors of this article present a case study of a woman who had a trigger finger five years previously and returned with symptoms of another in the same finger of the opposite hand. She wants advice as to how to proceed with treatment - injection or surgery?

Usual first-line treatment for idiopathic trigger finger, a trigger finger of unknown cause, is injection with a corticosteroid. In this case, the patient developed non-insulin dependent diabetes, usually called Type 2 diabetes, since her first experience with trigger finger and people with diabetes may need a different type of steroid and injection procedure than those without diabetes.

There have been cases reported of patients with trigger fingers who were treated successfully with splinting alone of their affected finger, for six to nine weeks. Most did well if the symptoms were mild and had not been present for a long time. However, there are not many studies that combine splinting with steroids. Studies that look at steroid injections alone report about a 57 percent effectiveness rate. One study, done by Rhoades and colleagues found that if the patient experienced pain and symptoms for more than four months, they were not likely to respond well to steroid injections. Other researchers, led by Newport, found that people with only one affected finger and who had symptoms for less than six months, did respond better to one steroid injection. In yet another study, Rozental and colleagues found that younger patients who had more than one affected finger and a history of other issues involving the tendons in the arms and hands were more likely to need a second injection or surgery.

The researchers for this study were only able to find one study, by Ring and colleagues, who studied two types of injection: triamcinolone and dexamethasone. In Ring's study, the first medication worked more quickly than the second, but the effects only lasted as long as did the second medication's injection. Other researchers looked into where the injection was given. Kazuki and colleagues injected another type of medication, betamethasone, along with a numbing agent lidocaine, together. In 74 percent of the cases, the symptoms were relieved and after one injection, 50 percent had another occurrence of trigger finger. In another study by Taras and colleagues, the researchers tested the type and location of injection using a dye to identify the delivery site. The goal was to inject intrasheath, into the target area, but in 17 percent of the cases, the medication went subcutaneous, or under the skin. However, the researchers found that there weren't any differences in patient outcome whether the medication was intersheath or subcutaneous. Other researchers looked at mid-axial, into the finger and compared this to injection through the palm of the hand. There was more pain and recurrence rates in those who received injections through the palm.

Further studies of treating trigger finger was done among people who have diabetes. Researcher Baumgarten and colleagues investigated the use of corticosteroids in both type 1 (insulin dependent) and type 2 diabetes. The patients who received the corticosteroid had about the same level of success as those who received a placebo injection. Yet, only 40 percent of the patients with diabetes went on to have surgery.

Injecting with triamcinolone and lidocaine together resulted in a success rate of 41 percent in a study done by Rozental, and having type 2 diabetes did not have any effect on the outcomes. However, six study patients had type 1 diabetes and none of them had relief from the injection and went on to have surgery. Finally, another study had reports of 41 percent and 72 percent success rates in people with type 1 and type 2 diabetes, respectively.

Taking these studies and their findings into account, the authors write that "in patients without diabetes, up to 2 corticosteroid injections work more than half the time, but the recurrence rate is uncertain." However, many studies are too short and for adequate assessment of treatment success, studies should follow patients for at least one full year.

In terms of the patient presented in this case study, the authors state that they would advise the patient that there is a 60 percent success rate with the injection if she has not had the symptoms for too long. The fact that she is not dependent on insulin is an advantage, leads to better success rates that if she had been on insulin. However, if she had been insulin-dependent, then the authors would advise the patient that surgery is a viable option, particularly if she was looking for quick and predictable results.
Jorge L. Brito, MD, and Tamara D. Rozental, MD. Corticosteroid Injection for Idiopathic Trigger Finger. In The Journal of Hand Surgery. May 2010. Vol. 35. No. 5. Pp. 831-833.