title: Radiotherapy induced hip joint avascular necrosis-Two cases report.
abstract: BACKGROUND
  Avascular necrosis (AVN) refers to the death of osteocytes and osteoblasts. Sites such as the femoral head, the head of the humerus and the mandibula with restricted access to local blood supply are particularly vulnerable to osteonecrosis. A COMBINATION OF SEVERAL FACTORS IS RESPONSIBLE FOR ISCHAEMIA AND IS ASSOCIATED WITH AVN: corticosteroids, alcohol abuse, Cushing's syndrome, SLE, systemic vasculitis, RA, scleroderma, haemoglobinopathies, radiotherapy. Management is based on proper diagnosis and treatment - conservative, pharmacological or surgical. Radiotherapy has become an integral part of the therapeutic programme of cancer patients. However, early and late after-effects of irradiation still constitute a significant issue in clinical practice.
  
  
  OBJECTIVE
  The aim of this report is to present two cases of acetabular protrusion and femoral head deformities after a therapeutic pelvic irradiation and draw physicians' attention to that clinical problem which continues to be underestimated.
  
  
  METHODS
  This report documents two cases of acetabular protrusion and femoral head deformities after a therapeutic pelvic radiation.
  
  
  RESULTS
  Avascular necrosis (AVN) constitutes a severe and challenging long-term complication in radiation oncology.
  
  
  CONCLUSIONS
  It is necessary to take into account bone structures among organ at risk (OAR) involved in irradiation fields. The detailed analysis of the dose distribution and the use of collimators allow to decrease the total dose to OAR. An adequate management, early diagnosis and prompt, proper treatment may protect patients from long-term morbidities.
authors.affiliation: Department Radiotherapy, Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-100 Gliwice, Poland.
authors.forename: Lukasz
authors.initials: L
authors.lastname: Michalecki
authors.affiliation: Department Radiotherapy, Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-100 Gliwice, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Gabryś
authors.affiliation: Department Radiotherapy, Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-100 Gliwice, Poland.
authors.forename: Roland
authors.initials: R
authors.lastname: Kulik
authors.affiliation: Department Radiotherapy, Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-100 Gliwice, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Wydmański
authors.affiliation: Department Radiotherapy, Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-100 Gliwice, Poland.
authors.forename: Krystyna
authors.initials: K
authors.lastname: Trela
keywords: Aseptic necrosis; Avascular necrosis; Osteoradionecrosis; Radiotherapy