Abstract
Purpose
The purpose of this study is toevaluate the clinical and radiologic results after high flexiontotal knee arthroplasty, Lospa®(Corentec Inc.) with 10mm cutting of posterior femoral condyle and LPS-Flex®(Zimmer Inc.) with 12.5mm cutting of posterior femoral condyle.(Fig. 1)
Materials and Methods
We prospectively compared 205 knees in 128 patients who underwent arthroplasty usingLospa®(groupA) and 63 knees in 48 patients who underwentarthroplasty using NexGen LPS-Flex®(group B) from September 2010 to March 2012 at Department of Orthopaedic Surgery, Sun General Hospital (Daejeon, Korea). Mean follow-up period was 33 months(24–42) in group A and 33months(23–45) in group B, and mean age was 69.5 in group A, 70.4 in group B. The radiologic analysis included the change of mechanical axis deviation and femoro-tibial angle, implant position (α,β,γ,δ)(Fig 2). The clinical results were evaluated according to Hospital for special surgery (HSS), Knee society score (KSS), and range of motion.
Results
Mechanicalaxis deviations were change in varusfrom 34.8 mm to 2.6 mm(P=0.02) in group A, and change in varusfrom 32.9mm to 3.1mm(P=0.03) in group B; no statistically significant difference was observed between them (P=0.12). Femoro-tibial angles were varus 4.3° to valgus 6.6°(P=0.02) in group A, and varus 3.9° to valgus 5.7°(P=0.03) in group B;no statistically significant difference was observed between them(P=0.27). Implant positions were α=96.3°, β=90.7°, γ=1.0°, δ=88.2° in group A, and α=97.1°, β=90.3°, γ=1.5°, δ=88.9° in group B; no statistical significance in implant position was observed between the two groups (P=0.23 in α, P=0.19 in β, P=0.14 in γ, P=0.15 in δ). Mean HSS improved from 48.5 to 93.6 (P=0.02) in group A, and from 51.5 to 89.7(P=0.03) in group B; no statistical significal difference was observed between the two groups(P=0.12). Mean KSS improved from 55.1 to 93.4(P=0.03) in group A, and from 48.2 to 92.2(P=0.02) in group B; no statistical significal difference was observed between the two groups(P=0.12). Range of motion improved from 106.4°to 123.2°(P=0.01) in group A, and from 105.0° to 125.0° (P=0.03) in group B; no statistical significal difference was observed between the two groups(P=0.16).
Conclusions
Lospa®total knee arthroplasty showed excellent earlyradiologic, clinical results and no statistically significant difference in the results was observed between Lospa®and LPS-Flex®.
