Trigger fingers and trigger thumb are the result of stenosing tenosynovitis of the flexor tendons at the level of the metacarpals.
The term stenosing comes from the Greek “steno” and means tightening or narrowing. The pathophysiology of this condition is due to compression of the flexor tendons to the thumb and the rest of the digits from the flexor retinaculum and pulley system that suspends the tendons at the level of metacarpal heads.
Trigger finger causes catching of the flexor tendon at the level of the metacarpal, which sometimes can be associated with popping on an effort to extend the involved digit. Sometimes the popping of the tendon can create an audible sound.
The first line treatment for trigger fingers is cortisone injections. I typically use Kenalog 10 or Kenalog 40 for these injections, which I dilute with 1% lidocaine to make it more comfortable. It is important to make sure that the injection targets the stenosing pulley space or sub-space itself and does not seep in the surrounding tissues. This is very important. And requires expertise. The initial cortisone injection will be effective in the majority of patients and can last from a few months to many years. After a successful initial treatment with cortisone I will employ a second and perhaps a third one. However, if the symptoms of catching and popping come back or never completely go away then I recommend surgery.
Trigger fingers and trigger thumbs respond excellent to surgical therapy. Surgery is the definitive treatment for trigger digits. Surgery entails release or division of the constricting band or pulley through a small incision over the metacarpals. This incision is about 2cm.
After surgery relief is immediate. Dressings entail a soft splint. Sutures come out after about 10-14 days.