The infrahyoid muscles, or strap muscles, are a group of four pairs of muscles in the anterior (frontal) part of the neck. The four infrahyoid muscles are the sternohyoid, sternothyroid, thyrohyoid and omohyoid muscles.
Excluding the sternothyroid, the infrahyoid muscles either originate from or insert on to the hyoid bone.
The term infrahyoid refers to the region below the hyoid bone, while the term strap muscles refers to the long and flat muscle shapes which resembles a strap. The stylopharyngeus muscle is considered by many to be one of the strap muscles, but is not an infrahyoid muscle.
In human anatomy, a hamstring (/ˈhæmstrɪŋ/) is any one of the three posterior thigh muscles in between the hip and the knee (from medial to lateral: semimembranosus , semitendinosus and biceps femoris ). The hamstrings are susceptible to injury. In quadrupeds, the hamstring is the single large tendon found behind the knee or comparable area.