Method and apparatus are disclosed for distracting tissue and particularly spinal tissue. The device and method may include insertion of at least one elongated member and an augmenting member to form a structure between the tissues to be distraction, such that a dimensional aspect of the structure is augmented upon movement of the augmenting structure.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

A joint replacement balancing system which provides real-time feedback to a surgeon during a joint replacement surgery to assist the surgeon to balance a joint replacement. The joint replacement balancing system includes a non-transitory processor-readable medium storing code representing instructions to cause a processor to receive a signal from a joint balancing apparatus, determine if the joint replacement is out of balance, determine a corrective course of action to bring the joint into balance and generate and display to the surgeon during the joint replacement surgery a recommended corrective course of action to complete the joint replacement surgery.

The disclosure provides example methods and non-transitory computer-readable mediums for acetabular cup placement. An example method includes a processor (a) determining for a first patient a sagittal acetabular cup position in the form of a standing AI, a seated AI and a SAA based on (i) a standing SS relative to a normative SS, (ii) a dSS between a standing position and an upright seated position, (iii) a femoral version corresponding to a femoral version outlier position, and (iv) a PFA to correspond to a PFA outlier position in a standing position or an upright seated position, (b) determining a coronal acetabular cup position in the form of a supine coronal anteversion and at least one of a supine or a standing coronal inclination based on the sagittal acetabular cup position, and (c) determining a post-operative standing AI and a post-operative seated AI based on the coronal acetabular cup position.