A measurement apparatus includes a body suit for a body that includes an appendage having a pivotable joint, the body suit comprising a sleeve to cover the appendage, wherein a first portion of the sleeve is configured to cover the pivotable joint. One or more multi-core optical fiber sensors is/are within or on the sleeve in a routing pattern that is substantially aligned with a longitudinal axis of the sleeve except within the first portion and that is at least partially transverse to the longitudinal axis within the first portion. An optical shape sensing system coupled to the one or more multi-core optical fiber sensors sends light into the one or more multi-core optical fiber sensors and determines a position of each of the multiple appendages based on reflected optical signal measurements detected from one or more multi-core optical fiber sensors.