Abstract: A method and apparatus for monitoring posture deficiencies in the spine and including a flexible body (30) encapsulating a flexible operating arm (31) cantilevered from a base moulding (34). The operating arm (31) is provided with upper (37) and lower (40) strain gauges bonded to the upper and lower faces respectively of the operating arm (31) at the point beyond the stiffening base moulding (34) to ensure that differential strain is experienced on deflection of the operating arm (31). Wire tails (41) are terminated as a PCB assembly (45) mounted to the printed circuit support (35), which assembly comprises a PC board bearing an LSI processor (46), rechargeable battery (47), vibrating motor (50) and inductive coil (51) selected to fulfil the functions of transmitting and receiving element, and inductive power supply for charging the battery (47), under the control of processor (46).