Mild: PIP flexion 60 to 80 degrees
Moderate: PIP flexion 20 to 59 degrees
Severe: PIP flexion less than 20 degrees or MCP flexion contracture
Abnormalities of these muscles may cause an ill defined pain, weakness, stiffness, or any combination. Treatment options depend on whether the problem is thought to involve reversible inflammation, fibrosis or fixed contracture. Most early cases respond well to specific intrinsic stretching exercises. Refractory cases may require surgical release or lengthening.