An apparatus for promoting bone repair or integration of a prosthesis in a bone, comprises a support (10), such as an intramedullary pin, securable to a bone (12). A plurality of strain gauges (14a, 14b, 16a, 16b, 18a, 18b, 20a, 20b) are attached to the support (10) at respective different positions of the support (10). The strain gauges (14a, 14b, 16a, 16b, 18a, 18b, 20a, 20b) detect strain on deformation of the support. The apparatus also comprises a controller (22) and a signalling system (24). The signalling system (24) is operatively connected to the strain gauges (14a, 14b, 16a, 16b, 18a, 18b, 20a, 20b) and operatively connected to the controller (22) for providing to the controller (22) signals indicative of respective strains detected by the strain gauges (14a, 14b, 16a, 16b, 18a, 18b, 20a, 20b). The apparatus also comprises a functional electrical stimulation device (36) for applying a functional electrical stimulation to a muscle (56). The controller (22) is operatively connected to the functional electrical stimulation device (36) so that the controller (22) controls the application of functional electrical stimulation dependent on the signals provided by the signalling system (24).
