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D R Lionberger

Publications and source records attributed to D R Lionberger.

5 recordsLinked to original sources

A knowledge-based computer-aided design and manufacturing system for total hip replacement.

A knowledge-based computer-aided design and manufacturing system (CAD-CAM) has been developed for total hip replacement. Knowledge-based refers to the fact that the design process is a computer program that has been provided with preprogrammed design rules. Compared with conventional CAD-CAM systems, the knowledge-based system is automated, requires less designer intervention, and increases the accuracy of the design process. The capabilities of the system make it ideal for the design of standard and custom total hip replacement. A full-fill, press-fit custom total hip replacement has been designed using the knowledge-based system. The early clinical results of a series of 37 replacements in 31 patients is described in this paper.

Adult↗

Treatment of rheumatoid synovitis of the knee with intraarticular injection of dysprosium 165-ferric hydroxide macroaggregates.

One hundred eight knees of 93 patients with seropositive rheumatoid arthritis and persistent synovitis of the knee were treated with an intraarticular injection of 270 mCi of dysprosium 165 bound to ferric hydroxide macroaggregate. Leakage of radioactivity from the injected joint was minimal. Mean leakage to the venous blood 3 hours after injection was 0.11% of the injected dose; this corresponds to a mean whole body dose of 0.2 rads. Mean leakage to the liver 24 hours after injection was 0.64% of the injected dose; this corresponds to a mean liver dose of 3.2 rads. In 7 additional patients examined, there was negligible or near negligible activity found in the draining inguinal lymph nodes. One-year followup was possible for 74 knees (63 patients). Sixty-one percent of the knees had good results, 23% had fair results, and 16% had poor results. There was a direct correlation between the radiographic stage and response to treatment. In knees with stage I radiographic changes, 72% showed good results; 93% showed improvement. In knees with stage II changes, 59% showed good results; 81% showed improvement. These preliminary results indicate that dysprosium 165-ferric hydroxide macroaggregate is an effective agent for radiation synovectomy. The low leakage rates observed offer a definite advantage over agents previously used.

Adult↗

The modified Blair fusion.

The Blair fusion is the accepted method to achieve an ankle arthrodesis in the presence of avascular necrosis or absence of the body of the talus. This procedure has not however, been reliable. A pseudarthrosis rate of 28% and fibrous ankylosis of the foot secondary to prolonged immobilization compromise the end result. A tibiotalar compression arthrodesis has been developed using an intermediate hip compression screw and a modified Stone staple. Five patients with avascular necrosis of the talus underwent a modified Blair fusion. Protected weightbearing was started at 6 weeks and healing occurred within 3 months. Although the number of cases is small, this study indicates that the addition of compression fixation to the Blair arthrodesis will significantly decrease the pseudarthrosis rate and perhaps the healing time.

Adult↗