Trigger finger manifests by a clash (collision) sometimes painful during mobilisation on flexion (closing) or extension (opening) of the finger.
It is due to the presence of a nodule on the tendon, which catches when engaging in the sheaves.
This clash irritates the nodule and makes it grow bigger; thus it blocks more; it is a self-sustaining phenomenon.
The reasons for the appearance of this nodule are varied: poor hydration, significant efforts, repeated efforts. Sometimes the appearance is totally spontaneous.
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