This is a common condition associated with inflammation of the tendon lining in the finger. Patients with this problem experience pain and catching of the affected finger, making movement difficult.
Figure A: Finger in a straight position
Figure B: When the finger is flexed, the tendon lining swells up and causes the finger to lock.
Bending or straightening of the finger causes a "catch" and/or produces a 'clicking' sound or pain.
Tendons that help bend the thumb and fingers slide through a snug tunnel. Repetitive movement of the flexor tendon slipping in and out of the tunnel can cause the tunnel opening to become thicker and smaller, or the tendon lining to thicken, so it is harder to pass through. As you try to straighten the finger, the tendon becomes momentarily stuck at the mouth of the tunnel, and then pops as the tendon squeezes through the tight area.
Figure C shows a steroid injection into the tendon sheath.
The goal of treatment in trigger finger/thumb is to eliminate the catching or locking and allow full movement without discomfort. Swelling around the flexor tendon and tendon sheath must be reduced to allow smooth gliding of the tendon. Stretching of the fingers and taking an oral anti-inflammatory medication may sometimes help. An injection of steroid into the potential space between the tendon and pulley is often effective in relieving the trigger finger/thumb. If non-surgical forms of treatment are not effective, surgery will be a good option.
Figure D: Surgical incision and Figure E: Wound following closure