Thursday, March 16, 2000
Ankylosing spondylitis (AS) is a seronegative spondyloarthropathy that primarily affects the sacroiliac joints, spine, hips and less commonly, the knee joint. Researchers presented a study in poster exhibit 132, showing that cemented total knee arthroplasty (TKA) for patients with AS provides excellent pain relief and durable fixation. Patients with AS are however at risk for developing stiffness and heterotopic bone formation, the researchers said.
The researchers reviewed results of 24 TKAs in 16 patients with AS. There were 13 males and three females with an average age of 59 years (ranging from 28 to 61 years) at the time of arthroplasty. The diagnosis of AS was established using the New York criteria. All implants were placed with methylmethacrylate. The average length of follow-up was 9.6 years (two to 21 years).
Knee Society pain scores improved from an average of 33 preoperatively to 78 at latest follow-up. The functional score improvement was less impressive, averaging 32 preoperatively and increasing to 50 at latest follow-up.
The mean arc of motion prior to arthroplasty was only 79 degrees and improved to 89 degrees at final follow-up. Six knees (25 percent) had heterotopic bone in the quadriceps mechanism noted radiographically. Two knees (8 percent) required manipulation under anesthesia secondary to poor motion. There were no revisions. All of the components were radiographically stable. One patient developed a superficial wound infection. There were no deep infections.
The researchers, all of Mayo Clinic, Rochester, Minn., are Javad Parvizi, MD, resident; Gavan P. Duffy, MD, resident; Robert T. Trousdale, MD, associate professor.
|2000 Academy News March 16 Index B|
Last modified 06/March/2000 by IS