Patellofemoral arthroplasty: the other unicompartmental knee replacement.

Many patients with signs and symptoms of patellofemoral arthritis do not respond well to conservative treatment modalities. Patients with isolated patellofemoral arthritis with severe anterior knee pain may be candidates for patellofemoral arthroplasty. The success of the procedure and the long-term survivorship of the implant rely on good surgical technique and adherence to strict indications and contraindications in patient selection. Newer implant designs have also contributed to improved outcomes.

Ethyl chloride improves antiseptic effect of betadine skin preparation for office procedures.

To determine if ethyl chloride is an effective disinfectant alone or combined with povidone iodine in a clinical setting, 35 volunteers had different portions of their knees swabbed with sterile cotton-tip applicators after an area of skin was prepared with either ethyl chloride alone, povidone iodine alone, or povidone iodine followed by ethyl chloride. An area with no preparation at all served as the control. Specimens were then cultured on agar plates and bacterial growth assessed. When the data was categorized as colony forming units (CFUs) or no CFUs, both ethyl chloride and povidone iodine used alone had significantly fewer specimens with CFUs (p=0.001) than controls, but were not significantly different from each other (p=0.18). Additionally, the combination of povidone iodine followed by ethyl chloride spray had significantly fewer samples with CFUs than either product used alone (p=0.001). In addition to its local anesthetic properties, ethyl chloride may be an effective disinfectant alone and may improve skin disinfection when used with povidone iodine compared to povidone iodine alone.

Patellar button wear patterns in well-functioning total knee arthroplasty retrievals.

One of the common reasons for early revision or poor outcome in total knee arthroplasty is due to patellar maltracking, loosening, or pain. The analysis of how the patellofemoral mechanism operates and wears in vivo has not been a focus of many retrieval studies. This paper describes the wear pattern observed on patellar buttons from well-functioning TKA specimens that were harvested as part of a donor program. The attempt was to describe the variations in wear patterns to see if any commonalities existed that may predict a well-functioning patellofemoral mechanism after TKA.

Patellofemoral arthroplasty: the other unicompartmental knee replacement.

Patellofemoral arthritis is a relatively common condition, affecting up to 24% of women and 11% of men over the age of fifty-five years who have symptomatic osteoarthritis of the knee. Isolated patellofemoral arthritis is not as prevalent and has been reported to occur in 9% of radiographs of symptomatic knees in individuals over the age of forty years. Approximately 75% of all patellofemoral arthroplasties are done in women, and the increased frequency of patellofemoral disease may be related to the frequency of knee malalignment and dysplasia in women, although some studies have noted no sex-specific differences in knee kinematics.