A sensing insert device (100) is disclosed for measuring a parameter of the muscular-skeletal system. The sensing insert device (100) can be temporary or permanent. Used intra-operatively, the sensing insert device (100) comprises an insert dock (202) and a sensing module (200). The sensing module (200) is a self-contained encapsulated measurement device having at least one contacting surface that couples to the muscular-skeletal system. The sensing module (200) comprises one or more sensing assemblages (1802), electronic circuitry (307), and communication circuitry (320). An interconnect stack within the sensing module (1700) couples at least one circuit board (1612 and 1616) to one or more sensing assemblages (1802). The interconnect stack includes at least one flexible interconnect (1506) that couples to the circuit board (1612 and 1616). The flexible interconnect (1506) can be in a path for conducting an energy wave through the sensing assemblage (1802).