Jae Sung Myung MD, Presenter: Nothing to Disclose

Suk-Joo Hong MD, Abstract Co-Author: Nothing to Disclose

Won Yong Shon, Abstract Co-Author: Nothing to Disclose

Sang Hwan Han, Abstract Co-Author: Nothing to Disclose

Cheol Min Park MD, Abstract Co-Author: Nothing to Disclose

To evaluate the correlating factors of periacetabular osteolysis after total hip arthroplasty (THA) using volumetric measurement of osteolysis on 16 channel multi-detector row computed tomography (MDCT)

Authors reviewed retrospectively 118 THA prostheses in 97 patients with postoperative period ranging between 18 to 234 months (mean 82.1 months). Measurement of periacetabular osteolysis %volume using 3D computer-aided imaging program based on 16 channel MDCT scan, periacetabular osteolysis %area using radiograph, polyethylene %wear on CT coronal image, and linear wear rate on radiograph was performed. The correlation between %volume or %area of osteolysis and wear rates on CT or radiograph was analyzed. Age, sex, weight, and occupation of patients, type of polyethylene used, size, location, and external rotation angle of acetabular cup, postoperative duration, and Harris hip score were correlated with periacetabular osteolysis and polyethylene wear rate

Periacetabular osteolysis was observed in 43 cases (36.4%) on radiograph with mean %area 5.18% and in 103 cases (87.3%) on CT scan with mean volume 2304.28mm3 (23.8~61653.7 mm3). The mean linear wear rate was 0.071mm2/year on radiograph, mean %wear on CT scan was 24.7%. There was positive correlation of osteolysis %volume on CT with osteolysis %area on radiograph, polyethylene %wear on CT, and plain wear rate, respectively (r=0.73, 0.57, 0.57, p<0.01). The risk rate of CT osteolysis was estimated as 20% in general, 30% in 0.05mm2/y linear wear rate, and 50% in 0.10mm2/y linear wear rate. Patient’s occupation, postoperative duration, type of polyethylene used were the correlating factors of polyethylene wear rate (p<0.05). Harris hip score was significantly decreased when the osteolysis %volume was more than 10%.

The polyethylene wear rate measured on radiograph and CT scan is the reliable correlating factor of periacetabular osteolysis. Patient’s occupation, postoperative duration, type of polyethylene used, and Harris hip score are the other correlating factors of periacetabular osteolysis

The results can be used as a guideline to predict pelvic osteolysis after total hip arthroplasty.

Myung, J, Hong, S, Shon, W, Han, S, Park, C, The Correlating Factors of Periacetabular Osteolysis in Total Hip Arthroplasty using Volumetric Measurement of Osteolysis on 16 Channel MDCT.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5012050.html