Work-Related Risk Factors
forceful hand use
repetitive hand use
awkward postures during hand use (postures in extreme joint positions)
sharp tool handle edges
Double jointedness (hyperlaxity) of the wrist, thumb, or fingers is a risk factor for tendonitis near the double joint.
Specific areas of tendonitis may be traced back to specific activities that use the affected muscle or tendon. For example:
Work involving repetitive hand motion with frequent thumb extension, or extreme lateral wrist movements is risk factor for deQuervain's syndrome (thumb tendonitis).
Repetitive wrist flexion against resistance is a risk factor for tendonitis of the wrist flexor tendons.
Wrist flexor or extensor tendonitis is more likely to occur when workers are not accustomed to doing a task that involves force, repetition, or awkward postures.