According to recently published results, mechanically out-of-range alignment was linked with higher tibial component migration after total knee arthroplasty.
Researchers measured coronal alignment parameters in full-leg radiographs from 85 cemented TKAs. Median follow-up was 11 years. Of the 85 TKAs, three underwent revision for aseptic loosening and four were considered loose. Investigators assessed the postoperative hip-knee angle relative to both the mechanical axis and constitutional alignment on tibial component migration. Linear mixed-effects model adjusted for sex, age, preoperative alignment, diagnosis and BMI was used for analysis.
In mechanically in-range knees, investigators did not see loose tibial components. However, they found all loose tibial components were out of range. After 5 years, the greatest mean migration in mechanically varus knees was 1.55 mm, was 1.07 mm for valgus knees and was 0.77 mm for in-range knees. Loose tibial components were seen in constitutionally in-range knees and in out-of-range knees. Comparable migration was seen among constitutionally in-range knees; however, more was seen in varus and in valgus knees, according to results from mixed model analyses. – by Monica Jaramillo
Disclosures: The authors report no relevant financial disclosures.