UniSpacer arthroplasty of the knee
ABSTRACT The operative treatment of medial compartment knee arthritis is controversial. The purpose of the present study was to report the experience of a single surgeon with the UniSpacer arthroplasty for the treatment of isolated medial compartment arthritis of the knee.
From April 2002 through November 2002, thirty-seven UniSpacer arthroplasties were performed in thirty-four patients for the treatment of arthritis that primarily involved the medial compartment of the knee. The Ahlbäck radiographic evaluation scale was used to grade the severity of arthritis; the mean preoperative score was 2.6 points for the medial compartment and 0.5 point for both the lateral and patellofemoral compartments. The study group included eighteen women (nineteen knees) and sixteen men (eighteen knees) who had a mean age of fifty-five years (range, forty-two to seventy-five years) at the time of surgery. Twelve patients had had a previous arthroscopic meniscectomy. The mean preoperative Knee Society function score was 60 points (range, 40 to 80 points), and the mean preoperative Knee Society objective score was 62 points (range, 40 to 76 points).
After a mean duration of follow-up of twenty-six months (range, twenty-four to twenty-nine months), there were no excellent, ten good, fifteen fair, and twelve poor results. The mean postoperative total function score was 69 points (range, 40 to 82 points), and the mean Knee Society objective score was 72 points (range, 45 to 88 points). Six of the twelve poor results were in knees that had dislocation of the UniSpacer. All twelve knees were revised to a total knee arthroplasty.
On the basis of this experience, we do not recommend UniSpacer arthroplasty for the treatment of degenerative arthritis of the medial compartment of the knee.
SourceAvailable from: Larry Edwin Miller[Show abstract] [Hide abstract]
ABSTRACT: Traumatic knee injury is common in young adults and strongly contributes to premature development of knee osteoarthritis (OA). Post-traumatic knee OA poses a therapeutic dilemma to the physician, since no known therapy has an acceptable safety profile, effectively relieves joint pain, and enjoys reasonable patient acceptance. Consequently, these young patients will ultimately be faced with the decision to either undergo surgical intervention, despite prosthesis durability concerns, or to continue with ineffective nonsurgical treatment. Emerging therapies, such as biologics, disease-modifying drugs, partial joint resurfacings, and minimally invasive joint-unloading implants are currently being studied to fill this therapeutic void in the young patient with post-traumatic knee OA.Open Access Journal of Sports Medicine 04/2014; 5:73-79. DOI:10.2147/OAJSM.S61865
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ABSTRACT: A class of two-diode microwave mixers (called "magic T") is defined and its equi valent single-diode models are developed. The models are used at nonlinear. linear and noise steps of the analysis to predict mixers properties and draw general conclusions. A "crossbar" mixer example illustrates the paper.Microwave Conference, 1988. 18th European; 01/1988
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ABSTRACT: There is currently a growing demand for unicompartmental knee replacement (UKR) to treat degenerative osteoarthritis or osteonecrosis of a single compartment of the knee. This procedure has evolved significantly over the past three decades and we here present a brief review of the literature on this topic. This historical overview traces the hypotheses that have led to the modern state of the art in minimally invasive UKR surgery and to the revival of the concept of interpositional hemiarthroplasty.