Inclusion Criteria:

The inclusion criteria for this study are current indications for primary total hip arthroplasty utilising a cementless femoral component. These include pain, deformity and loss of function, which are not responsive to medical treatment. Subjects will only be considered eligible and must only be recruited if they meet all of the following criteria:

• Administrative - The subject is able to understand the study, is willing to give voluntary, written, informed consent, will co-operate with assessment procedures and is geographically able to comply with the post-operative follow-up regime.
• Age - The subject's age is between 18 and 75 years inclusive.
• Sex - Male or female subjects may be recruited to the study.
• Diagnosis - Subjects must be undergoing primary total hip replacement (THR) surgery for non-inflammatory degenerative joint disease including osteoarthritis, avascular necrosis, post-traumatic arthritis, fractured neck of femur and non-union of fractured neck of femur, slipped upper femoral epiphysis (SUFE), or Perthes disease.
• Suitability - Subjects who in the opinion of the Investigator are considered to be suitable for treatment with the devices involved in the study.

Exclusion Criteria:

• Subjects undergoing revision procedure to the operative hip.
• Subjects who have had a previous femoral osteotomy to the operative hip.
• Subjects who have a history of active sepsis in the joint.
• Subjects who have been diagnosed with primary or secondary carcinomas in the last five years (excluding basal cell carcinoma or cervical carcinoma).
• Subjects with any condition, which may, in the opinion of the Investigator, interfere with the total hip replacement's survival or outcome, e.g. Paget's disease, Charcot's disease.
• Subjects with psycho-social disorders, which, in the opinion of the Investigator, would limit rehabilitation.
• Subjects' weight is > 100 kg.
• Subjects with femoral head necrosis on the non-operated side (radiostereometric analysis [RSA] and dual energy x-ray absorptiometry [DEXA] subjects only).
• Subjects who have a fracture of the femur > 6 months old (RSA and DEXA subjects only).
• Subjects diagnosed as having ankylosing spondylitis (RSA and DEXA subjects only)
• Subjects with a known history of poor compliance to medical treatment.