S20.46 - Insect bite (nonvenomous) of back wall of thorax S20.4 - Other and unspecified superficial injuries of back wall of thorax S20.46 - Insect bite (nonvenomous) of back wall of thorax S20.461 - Insect bite (nonvenomous) of right back wall of thorax S20.462 - Insect bite (nonvenomous) of left back wall of thorax S20.469 - Insect bite (nonvenomous) of unspecified back wall of thorax