The ACTIVE Trial: A Prospective Randomised Control Trial Of The H1 Implant Versus Total Hip Replacement

Inclusion Criteria: * Patient requires unilateral primary hip arthroplasty due to primary osteoarthritis, osteoarthritis secondary to e.g. trauma, avascular necrosis or developmental hip dysplasia, or inflammatory arthritis. * Patient is willing to comply with study requirements. * Patient plans to be available through 10 years postoperative follow-up. Exclusion Criteria: * Patient has a BMI greater than 40 kg/m². * Patient has active infection or sepsis (treated or untreated). * Patient has insufficient bone stock at the hip (\>1/3 necrosis of the femoral head or large and multiple cysts) or in general as in severe osteopenia or osteoporosis (t-score \< -2.5 as measured with BMD). * Patient is not skeletally mature. * Patient meets the contraindication criteria of the control device. * Patient already has another lower limb arthroplasty or arthrodesis or will require a further lower limb arthroplasty or arthrodesis within the subsequent 2 years. * Patient lacks capacity to consent. * Patient is unable to understand the native language of the country where their procedure is taking place