A New Method For Assessing Coronal Alignment of The Tibial Component in Total Knee Arthroplasty With an Intramedullary Rod
Background and Aim: Total knee arthroplasty (TKA) is the primary operative treatment for advanced knee osteoarthritis. Proper positioning of the femoral and tibial components is very important because malpositioning can cause undesirable results, such as implant loosening and persistent pain, and can compromise implant survival. Methods: A total of 200 patients who underwent unilateral TKA were evaluated for their coronal tibial alignments. Group A included the last 100 patients operated on before use of the technique described here, and Group B included the first 100 patients operated on after its implementation. The checking technique involved using an intramedullary rod to help assess the coronal alignment of the tibial components. If the measured angle between the tibial plateau surface and the intramedullary rod was not within 90° ±3°, then adjustment cuts were indicated to create an ideal tibial plateau surface. Results: Group B had a significantly lower rate of tibial coronal malalignment than Group A (5% vs. 28%, respectively; P < 0.05). Tibial plateau cuts of 17 patients were adjusted with this method in Group B, and the final coronal position of tibial plateaus were in the ideal limits (90 ± 3). Conclusion: The intramedullary rod checking method is a simple and effective technique for arthroplasty surgeons to assess final tibial component coronal alignment during TKA.