Post-Market Study of the Modular Revision Hip System

Inclusion Criteria: * Subject must be a candidate for revision hip arthroplasty * Subject must have either poor bone stock or deficiencies of the femoral head, neck or portions of the proximal femur * Subject's hip joint must be anatomically and functionally suited to receive the hip implant * Subject must have a body mass index of 40.00 or less (BMI) ≤ 40.00 at time of consent * Subject must be willing and able to sign the informed consent and follow study procedures * Subject must be 18 years of age or older (≥ 18) at the time of consent * Subject must be willing to return for all study visits * Subject (female) must not be pregnant at time of surgery Exclusion Criteria: * Subject must not be receiving a primary hip replacement * Subject has a mental condition(s) that may interfere with the subject's ability to give an informed consent or willingness to fulfill the study requirements (i.e., severe mental retardation such that the Subject cannot understand the informed consent process, global dementia, prior strokes that interfere with the Subject's cognitive abilities, senile dementia, and Alzheimer's Disease) * Subject has a condition that places excessive demand on the implant including high levels of physical activity (i.e. competitive sports, heavy physical labor) * Subject has a BMI \>40.00 * Subject is skeletally immature * Subject has osteomyelitis * Subject has loss of ligamentous structures * Subject is a prisoner * Subject is pregnant * Subject has an active infection or sepsis at time of surgery * Subject has a history of alcoholism or other addictions (current) * Subject has muscular, neurological or vascular deficiencies which compromise the affected extremity (i.e., Parkinson's Disease, Syringomyelia and Multiple Sclerosis, Charcot joints) * Subject has known materials sensitivity (to metals) * Subject has a physical condition that would eliminate or tend to eliminate adequate implant support or prevent the use of an appropriately-sized implant * Subject is unwilling to modify post-operative physical activities * Subject is younger than 18 years of age (\<18) at the time of consent