Allofit® IT With HXPE in Total Hip Arthroplasty

Inclusion Criteria: * Patient is skeletally mature. * Patient qualifies for primary unilateral or bilateral total hip arthroplasty (THA) based on physical exam and medical history including the following: * Avascular necrosis (AVN) * Osteoarthritis (OA) * Inflammatory arthritis (i.e. Rheumatoid arthritis) * Post-traumatic arthritis * Patient has no history of previous prosthetic replacement device (any type, including surface replacement arthroplasty, endoprosthesis, etc.) of the affected hip joint(s). * Patient has a Harris Hip Score \<70 in the affected hip * Patient is willing and able to provide written informed consent. * Patient is willing and able to cooperate in the required post-operative therapy. * Patient is willing and able to complete scheduled follow-up evaluations as described in the Informed Consent. * Patient has participated in the Informed Consent process and has signed the Ethics Committee approved informed consent. Exclusion Criteria: * The patient is: * A prisoner * Mentally incompetent or unable to understand what participation in the study entails * A known alcohol or drug abuser * Anticipated to be non-compliant. * The patient has a neuromuscular disorder, vascular disorder or other conditions that could contribute to prosthesis instability, prosthesis fixation failure, or complications in postoperative care. * The patient has a vascular (large and small vessel disease) insufficiency. * The patient has a neurologic condition in the ipsalateral or contralateral limb which affects lower limb function. * The patient has a diagnosed systemic disease that could affect his/her safety or the study outcome. * The patient is known to be pregnant. * The patient is unwilling or unable to give informed consent, or to comply with the follow-up program. * The patient has received an investigational drug or device within the previous 6 months. * The patient has an active or latent infection in or about the affected hip joint or an infection distant from the hip joint that may spread to the hip hematogenously. * The patient has insufficient bone stock to fix the component. Insufficient bone stock exists in the presence of metabolic bone disease (i.e. osteoporosis), cancer, and radiation. Note: Dual Energy X-ray Absorptiometry (DEXA) may be used to assess the presence of adequate bone stock. * The patient has osteoradionecrosis in the operative hip joint * The patient has a known sensitivity or allergic reaction to one or more of the implanted materials. * The patient has known local bone tumors in the operative hip. * The patient is Grade III obese with a Body Mass Index (BMI) \> 40.