The research aims to analyze the tibial component rotation using the finite element method by resecting the tibia in a transverse plane at an angle between 1.5° (external rotation) and -1.5° (internal rotation). We used a three-dimensional scanner to obtain the tibia's geometrical model of a cadaveric specimen. We then exported the surfaces of the tibial geometrical model through the Computer-Aided Three-dimensional Interactive Application (CATIA), which is a Computer-Aided Design (CAD) program. The CAD program three-dimensionally shaped the tibial component, polyethylene, and cement. Our analysis determined that the maximum equivalent stress is obtained in the case of proximal tibial resection at -1.5° angle in a transverse plane (internal rotation) with a value of 12.75 MPa, which is also obtained for the polyethylene (7.693 MPa) and cement (6.6 MPa). The results have shown that detrimental effects begin to occur at -1.5°. We propose the use of this finite element method to simulate the positioning of the tibial component at different tibial resection angles to appreciate the optimal rotation.
PURPOSE OF THE STUDY The aim of the study was to find out whether the frequency and intensity of patellar pain can be affected by individual rotational alignment of the femoral component in total knee arthroplasty, as compared with the standard 3 degrees of external femoral rotation in conventional procedures. MATERIAL AND METHODS In randomly selected patients treated for knee osteoarthritis by total joint replacement between January 2007 and January 2011, the occurrence of patellar pain was assessed. The evaluated knees were allocated to two groups. Group 1 included 350 knee joints with conventional femoral rotational alignment, i.e., 3 degrees of external rotation. Group 2 comprised 380 knee joints with an individual rotational alignment of the femoral component based on the condylar twist angle. Post-operative anterior knee pain was assessed on the following scale: 1, no pain; 2, occasional mild pain; 3, moderate pain; 4, severe pain. RESULTS In group 1, 312 knee joints were free from pain, 15 occasionally experienced mild pain, 15 had moderate and eight had severe pain. A total of 23 revision operations were performed for patellar pain at the anterior knee and pain around the patella refractory to non-steroidal anti-rheumatic and rehabilitation therapy. In group 2, there were 331 pain-free knees, 48 with occasional mild pain, one with moderate pain and no knee with severe pain. No revision surgery was required. One patient with moderate patellar pain underwent surgery for spinal canal stenosis; after that knee pain was only mild. The groups were compared, as to pain assessment results, using the test of equality of relative frequencies, i.e., score categories 1+2 versus 3+4 of 350 (group 1) equalled 23 (6.57%) were compared with 1 (0.26%) of 380 (group 2); the difference was significant (p < 0.001). Using the same test for comparison of the frequency of repeat operations, i.e., 23 (0.57%) of 350 (group 1) versus 0 (0%) of 380 (group 2), also gave a significant result (p = 0.001). DISCUSSION Mild and occasional pain was recorded in both groups, suggesting that femoral component malrotation is not the only cause of patellar pain following total knee arthroplasty. A markedly lower incidence of moderate and severe pain and no need for revision surgery found in group 2 provides evidence that the use of individual rotational alignment of the femoral component is fully justified. CONCLUSIONS An individual rotational alignment of the femoral component can significantly reduce the incidence of moderate to severe patellar pain or even need for revision surgery.
- MeSH
- lidé středního věku MeSH
- lidé MeSH
- patela patofyziologie MeSH
- pooperační bolest * etiologie prevence a kontrola MeSH
- rotace MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- totální endoprotéza kolene * klasifikace metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- MeSH
- hodnocení stavu výživy MeSH
- lidé MeSH
- nemoci kloubů epidemiologie etiologie klasifikace MeSH
- obezita epidemiologie klasifikace komplikace MeSH
- totální endoprotéza kolene klasifikace metody statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- srovnávací studie MeSH
- MeSH
- chirurgie s pomocí počítače metody statistika a číselné údaje trendy MeSH
- lidé MeSH
- protézy a implantáty klasifikace statistika a číselné údaje trendy MeSH
- totální endoprotéza kolene klasifikace statistika a číselné údaje trendy MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- srovnávací studie MeSH
- MeSH
- chirurgie s pomocí počítače metody statistika a číselné údaje trendy MeSH
- lidé MeSH
- miniinvazivní chirurgické výkony metody statistika a číselné údaje využití MeSH
- totální endoprotéza kolene klasifikace statistika a číselné údaje trendy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
- MeSH
- lidé MeSH
- počítačová rentgenová tomografie klasifikace metody statistika a číselné údaje MeSH
- rentgendiagnostika klasifikace metody statistika a číselné údaje MeSH
- totální endoprotéza kolene klasifikace metody statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
- MeSH
- chirurgie s pomocí počítače metody statistika a číselné údaje trendy MeSH
- formuláře a záznamy - kontrola a vedení metody statistika a číselné údaje využití MeSH
- lidé MeSH
- totální endoprotéza kolene klasifikace metody statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH