Abstract: The invention provides an inter-body spacer in the form of a vertebral body replacement. The spacer comprises a connector having, axially aligned, a socket and threaded socket. A threaded screw is receivable in the threaded socket of the connector at one side of the screw and an endplate receiving head is provided on the other end of the screw for receiving an endplate perpendicular to the axis. The spacer further comprises a cylindrical extension with one end rotatably receivable in the socket of the connector and an endplate receiving head on the other end of the extension for receiving an endplate perpendicular to the axis. A locating formation is provided on each endplate receiving head for locating the endplate at a specific angle about the axis. The spacer further comprises a selection of one or more end plates receivable on the endplate receiving head with the tissue engaging surface of the endplates being transverse to the axis of the spacer at differing angles.

Abstract: A voltage sensor detects a terminal voltage of a battery connected to a load and a current sensor detects a current flowing through the load. A voltage-current changing tendency calculation unit reads a detected voltage and a detected current detected by the voltage sensor and the current sensor and outputs, every predetermined period of time, plural data of the detected voltage and the corresponding detected current as dispersed data. A voltage-current approximating line calculation unit inputs the dispersed data and determines, based on the dispersed data, a voltage-current approximating linear function each time the predetermined period of time. A battery remaining capacity calculation unit determines, each time the voltage-current approximating linear function is determined, a remaining capacity of the battery based on the voltage-current approximating linear function.