AMIC Compared With Microfracture for Focal Articular Cartilage Damage of the Hip

Inclusion Criteria: 1. All patients aged 18-55 years 2. Hip pain lasting 6 months or more with no relief from documented non-operative modalities 3. Focal articular cartilage defects of the acetabulum on MRI, confirmed to be full thickness (International Cartilage Regeneration and Joint Preservation Society (ICRS) grade 3 or 4) during arthroscopic examination 4. Focal acetabular articular cartilage lesions measuring between 3 cm2 and 25 cm2 on MRI and confirmed on arthroscopic examination 5. Patient agrees to participate in the study-specific postoperative rehabilitation protocol 6. Patient can speak, read, and understand the language of the site 7. Patient has provided informed consent Exclusion Criteria: 1. Cartilage defects of the femoral head 2. Previous surgery on the study hip 3. Traumatic chondral injury of the hip from a single event 4. Presence of advanced osteoarthritis (Tonnis grade 3) or any other acute or chronic inflammatory joint disease 5. Known hypersensitivity or allergy to porcine collagen 6. Acute or chronic infection at the surgical site 7. Evidence of hip dysplasia (i.e., lateral centre edge angle \< 20˚) 8. Evidence of acetabular over coverage such as coxa profunda or coxa protrusion 9. Immunosuppressive or anti-proliferative medication use 10. Chronic pain syndromes 11. Significant medical co-morbidities (requiring assistance for activities of daily living (ADLs)) 12. History of paediatric hip disease 13. Uncontrolled diabetes 14. Contraindications to MRI imaging (e.g. claustrophobia) 15. Patient is involved in ongoing legal or workplace claims 16. Patient is incarcerated 17. Patient is pregnant or breastfeeding 18. Patient who will likely have problems, in the judgement of the investigator, with maintaining follow-up 19. Any other reason(s) the investigator feels is relevant for excluding the patient