Introduction: Legg-Calvé-Perthes-Disease (LCPD) most commonly affects boys between the ages of 4 and 8. It is an avascular necrosis of the upper femoral epiphysis. Its etiopathogenesis is unknown. Advanced cases necessitate innovative approaches beyond conservative measures. We report a challenging case involving radical treatment for advanced LCPD already complicated by hip and knee stiffness, managed with a two-stage total hip arthroplasty. Case presentation: We report the case of a 14-year-old with chronic left hip impairment and concurrent knee stiffness due to advanced LCPD. Initial conservative interventions proved ineffective. We decided to opt for a two-stage surgical strategy. The first stage involved femoral head ostectomy, cervico-cephalic prosthesis placement, and soft tissue tenotomy. Subsequent intensive rehabilitation achieved improved joint mobility. The second stage comprised total hip replacement using a ceramic-ceramic prosthesis. At last follow up, a favorable functional outcome was observed, and radiographs demonstrated a well-positioned and osteo-integrated prosthesis. Conclusions: LCPD is a serious condition, and the prognosis is significantly influenced by early diagnosis and appropriate management. In cases of advanced staged LCPD, prosthetic replacement becomes a suitable option, even in younger patients. Despite potential complications, the use of a two-stage approach, integrating surgical intervention and tailored rehabilitation, proved effective in restoring joint function. This case highlights the importance of personalized planning and a staged approach in addressing the multifaceted aspects of LCPD.