A body support and an operation-mode indicating system are provided. The body support apparatus 1 comprises a mount portion 5 with means for fixing the mount to a body, a support portion with at least one joint 31, and a means for limiting bending movement at the joint the limiting means being under the control of a controller. The controller has a first mode in which bending at the joints of the support portion is not limited, and a second mode in which bending at the joints of the support portion is limited. A light emitting device 58 under the control of the controller is also provided, which emits a first signal in the first mode and a second signal in the second mode, where the signals are distinguishable and within the peripheral vision of the surgeon. The controller may enter the first mode when a movement force is applied to the body support, the force being detected by a sensor.
