Periprosthetic Metastatic Lesion in Stem Region after THA. Case Study.

The paper describes a periprosthetic metastatic lesion in the stem region which developed 4 years after cementless total hip arthroplasty in a 64-year-old female patient. The patient underwent primary THA due to osteoarthritis in 2010. In June 2014, she presented with increasing hip pain. Diagnostic imaging revealed a periprosthetic osteolytic lesion in the stem region. The patient was referred to the Orthopaedic Department for further evaluation with a suspicion of pyogenic osteomyelitis. An open surgical biopsy was performed. Histopathological examination indicated metastatic cancer originating from the lungs or thyroid. A PET-CT scan showed a metabolically active tumour in the parahilar area of the left lung with metastases to mediastinal and hilar lymph nodes, left adrenal gland, spleen and right proximal femur. In October 2014, a revision total hip arthroplasty with the use of a modular femoral resection stem was performed. Patient subsequently received oncologic treatment (chemotherapy and radiation therapy).