Trigger Finger Causes:
Most clinicians believe that the disorder
is caused by the tendon sheath because it becomes thickened
or swollen and pinches the tendon and prevents it from gliding
smoothly. But common sense reveals that the history of patients
suffering with Trigger Finger have one common denominator,
overuse, excessive use and/or abuse of the hands from work
and recreational activities.
Trigger Finger is usually (not
always) the result of direct injury to the tendon via micro-tears
resulting from direct and sudden trauma or tasks that required
repetitive use of the hands over long periods of time. And
as the body attempts to heal itself causes the formation
of scar tissue / fibrotic adhesion, and the swelling of the
tendon sheath is a secondary injury caused by friction between
the adhesion and the tendon sheath as the finger is flexed
and extended. This friction causes irritation, swelling, and
inflammation to both the adhesion on the tendon and to the
tendon sheath, thus resulting in a perpetual cyclic injury,
starting with the adhesion on the tendon, then the adhesion
irritates the sheath, then the sheath swells and pinches down
more so it irritates the adhesion even more, and continuing
to go back and forth again and again with both the tendon and
its sheath contributing to the cause-effect of Trigger Finger.
*Other contributors/factors of Trigger Finger
are Rheumatoid Arthritis, partial tendon lacerations, repeated
trauma from pistol gripped power tools, or long hours grasping
a steering wheel.
Trigger Finger may also be caused by an infection
of the synovium, resulting in the scarring and formation of
a nodule on the tendon. Trigger Finger can also be caused by
a congenital defect that forms a nodule inside of the tendon.
The condition is not usually noticeable until the infant begins
to use its hands.