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Indentation in the clavicle (collarbone)
Infraclavicular fossa (Mohrenheim's fossa)
Anterolateral view of head and neck (infraclavicular fossa labeled at bottom right)
The Infraclavicular fossa is an indentation, or fossa, immediately below the clavicle, above the third rib and between the deltoid muscle laterally and medioclavicular line medially.