Roentgenographic evaluation of a conical threaded acetabular cup.
A radiographic analysis was done of 83 primary hip arthroplasties performed in 70 patients.  The arthroplasty consisted of a truncated acetabular cup and a cemented titanium femoral stem.  The patients were evaluated at an average of 3.3 years postoperatively (range 2 to 5 years).  Using the method of DeLee and Charnley, the acetabulum was divided into three zones.  Specific attention was focused on the percentage of fill in the threads of zones 1 and 3 and the measurement of radiolucency in zone 2.  Over time, a large percentage of the acetabulae showed both a decrease in bone fill in zone 3 and an increase in radiolucency in zone 2.  By the third postoperative year, 16% (11 of 70) of the acetabulae had migrated.  Although all the hips had been rated good or excellent on the Charnley hip score, ie, receiving a 5 or better, 11 had migrated and 3 had been revised, indicating an unacceptable failure rate of the acetabular component.
Louisiana State University, Shreveport.
E M
EM
Keating
R A
RA
Czarkowski
M A
MA
Ritter
P M
PM
Faris
D000077:Acetabulum / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001861:Bone Regeneration; D005069:Evaluation Studies as Topic; D005260:Female; D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging; D006622:Hip Prosthesis / Q000295:instrumentation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D011859:Radiography