Autosomal Dominant Type I Osteopetrosis Is Related with Iatrogenic Fractures in Arthroplasty

Autosomal dominant osteopetrosis (ADO) is a sclerotic bone disorder due to failure of osteoclasts. ADO poses difficulties during arthroplasty because of the increased chance for iatrogenic fractures due to sclerotic bone. ADO is divided into two types based on radiological findings, fracture risk, and osteoclast activity. These differences suggest less brittle bone in patients with ADO I compared to that of patients with ADO II, which suggests a smaller chance of preoperative fractures during cementless arthroplasty in ADO I compared with that in ADO II. A case of cementless total knee arthroplasty in a patient with ADO I is presented. Total hip arthroplasty was performed during follow-up, and known major problems related to ADO II were experienced. Therefore, the differences between ADO I and ADO II may not be clinically relevant for an iatrogenic fracture during arthroplasty in patients with ADO.

Cementless Total Knee Arthroplasty with Posterior Cruciate Retention in Rheumatoid Arthritis

PURPOSE: The result of cementless total knee arthroplasty with posterior cruciate ligament retention in rheumatoid arthritis patients was evaluated. MATERIALS AND METHODS: Thirty patients (fifty knees) followed up after cementless total knee arthroplasty with posterior cruciate ligament retention was evaluated clinically and radiologically. Average follow up was 9.2 years(5.1~14.3). RESULTS: The mean HSS knee score improved from 47.4 preoperatively to 81.8 postoperatively, and the mean range of motion of 89.7 degrees preoperatively to 101.2 degrees postoperatively. The mean tibiofemoral angle was 4.9 degrees valgus. Posterior instability was observed in 1 case(2%) at the most recent follow up. Radiolucent line was observed in 41 cases(82%), and osteolysis was observed around tibial component in 13 cases(26%), and around femoral component in 4 cases(8%). Eight cases(16%) of revision was due to 1 case of aseptic loosening and osteolysis each, and the other due to polyethylene wear of patellar or tibial component. CONCLUSION: Although there are osteopenia in rheumatoid arthritis compared to osteoarthritis, cementless total knee replacement with posterior cruciate retention showed stable fixation. However, the new method for initial fixation of tibial component is needed because osteolysis around tibial component tended to start around cancellous screws.

Clinical Results of Cementless Total Knee Replacement / 대한정형외과학회잡지

Seventy four consecutive cementless Tricon-M total knee replacement were followed for two to eight years (average three and half years) at the Department of Orthopedics Kangnam St. Mary's Hospital Catholic University Medical College. Using the Hospital for Sepcial Surgery rating system we found that 86.6 percent of the knee were graded excellent or good, 8 percent fair and 5.4 percent poor. In four cases of complication, two patients had gram negative infection postoperatively and one had one stage revision using gentamycine mixed cement and the other who had delayed infection one year after surgery had arthroscopic irrigation and synovectomy. Other two complications were patella lateral sublugation but the realignment operation had been refused. In radiologic examination there were no radiolucenct loosening sign in any patella or femoral component but tibial radiolucency was seen in only three patients. Thirty four (46%) out of 74, cases showed tibial component subsidency (average 2.2mm) during the first one year follow up period but no further progression was seen in later follow up period. No correlation.between radiolucency or subsidence and knee scores was seen. Cementless fixation of all components in total knee replacement, including the tibia and patella, was highly successful and can be achieved without stress relief of the distal femur.