S66.311 - Strain of extensor muscle, fascia and tendon of left index finger at wrist and hand level S66.3 - Injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level S66.31 - Strain of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level S66.311 - Strain of extensor muscle, fascia and tendon of left index finger at wrist and hand level