EVOLUTION OF X-RAY IMAGES AND DEXA SCANS OF THE BONE GRAFTS INGROWTH IN PATIENTS AFTER REVISION HIP SURGERY

Andrzej Bednarek, Miroslaw JabloDski, Jacek Walawski, Jan Blacha
Orthopaedic and Traumatology Dept. Medical Academy of Lublin, 20-144 Lublin, Jaczewskiego 8 str., Poland

The prospective study included 20 consecutive patients operated due to hip prosthesis loosening using the frozen bone grafts (impacted bone grafting according Sloof). We perform the x-ray and DEXA measurements of the operated hip between 7 and 10th~ day after surgery and consequently 3, 6, 9 and 12 months later. Clinical evaluation was based on Harris Hip Score; DEXA measurements were made using Hologic QDR 4500A bone densitometer (orthopaedic software "Metal removal" by Hologic) and we perform standard plain AP radiograms of the hip. We asses evolution of radiological images, stem migration, clinical outcome, and perform statistical analysis of the Dexa measurements for each of the seven Gruen zones of bone surrounding the prosthesis stem. All patients were operated by 2 surgeons and the Dexa measurements were performed by one person on the same Hologic densitometer and with the use of the company software that eliminated the metal stem and cement mantle from the analysis. All included patients had complete DEXA and X-rays assessment and had good or very good clinical result. We correlate the Dexa measurements with the x-ray images and clinical result. We observed variations of bone density in Gruen zones with condensation phases of bone grafts density and some typical, characteristic (unique) changes of radiological images. Results might be helpful in prognosis and assessment of the bone grafts ingrowth.