RESUMEN
Osteogenesis Imperfecta is an inherited disease characterized by easily-broken bones, which manifests as multiple fractures with minimal trauma, joint laxity, sclerosis, blue sclera, and several other manifestations. Protrusio acetabuli is defined as the displacement of the femoral head so that it lies medial to the ischioilial line. In a skeletally mature patient with both Marfan syndrome and PA, an eventual hip arthroplasty is the only method available for correction of the deformity. However, in patients with Osteogenesis Imperfecta and PA, THA remains a controversial treatment. A 14-year-old male patient diagnosed with Osteogenesis Imperfecta Type 1A presented to the orthopedic surgery clinic complaining of groin pain of 1-year duration radiating to the thigh and knee. The patient was found to have radiologic signs of protrusion acetabuli. The patient was started with bisphosphonate and after medical failure, underwent a Total Hip Arthroplasty (THA). In post-operative follow-ups, the patient had relief of pain and was able to walk more comfortably and without a lump. The previously operated hip was examined and showed no signs of infection, dislocation, or fracture. Radiographic studies show no evidence of prosthesis failure or loosening with valgus position of the femoral stem and neutral acetabular angle. Ten years after the primary arthroplasty, the previously operated hip had maintained its stability and had no related complications. Despite the controversy surrounding the treatment of younger patients with hip failure, using total hip arthroplasty, this patient exhibited excellent results, with vast improvement in their symptoms and stability.