Abstract: A spacer block for gathering data to be used in the balancing of the joint arthroplasty or repair and in the selection of a trial insert which includes a first body piece and a second body piece. A plurality of sensors and a processor are positioned between the first body piece and the second body piece when the pieces are assembled together to form the spacer block. A chim is removably mounted to a top surface of the second body piece, the chim is associated with the plurality of sensors and positioned in relation to the plurality of sensors such that a force exerted on the chim by a weight bearing surface is detected by the plurality of sensors.