H-28 DELTA ST-C and Minima Retrospective Study.

Inclusion Criteria: * Underwent to a THA with DELTA ST-C cup and MINIMA stem in 2017 onwards * Both genders * Any race * A diagnosis in the target hip of one or more of the following: 1. Non-inflammatory degenerative joint disease such as osteoarthritis, avascular necrosis 2. Rheumatoid Arthritis 3. Post-traumatic arthritis 4. Fractures of femoral neck 5. Congenital or acquired deformity * Patient willingness to participate Exclusion Criteria: * Local or systemic infection * Septicaemia * Persistent acute or chronic osteomyelitis * Confirmed nerve or muscle lesion compromising hip joint function * Vascular or nerve diseases affecting the concerned limb * Poor bone stock (for example due to osteoporosis) compromising the stability of the implant * Metabolic disorders which may impair fixation and stability of the implant * Any concomitant disease and dependence that might affect the implanted prosthesis * Metal hypersensitivity to implant materials * Required revision of previous standard femoral stem * Age \< 18 years old * Any clinically significant pathology based on clinical history that the Investigator feels may affect the study evaluation including, but not limited to: 1. significant neurological or musculoskeletal disorders or disease that may adversely affect gait and compromise functional recovery 2. neuromuscular or neurosensory deficit which would limit the ability to assess the performance of the device 3. known metabolic disorders leading to progressive bone deterioration * Hip replacement on the contralateral side performed within less than one year