Early clinical results of electromagnetic navigation assisted total knee arthroplasty
CUI Wen-quan
JIANG Wen-xue
YUAN Li-yuan
QI Zhi-ming
BI Wei
HAN Ya-zhou
Abstract： Objective To retrospectively evaluate the accuracy of postoperative prosthesis implantation and reconstruction of lower limb alignment after total knee arthroplasty ( TKA ) using an electromagnetic ( EM ) navigation system, and to investigate the technical characteristics and early clinical results of EM navigation assisted TKA. Methods The data of 64 initial consecutive patients ( 100 knees ) who underwent primary TKA using an EM navigation system from July 2006 to February 2007 were retrospectively studied. There were 7 males and 57 females, whose mean age was 66.9 years old ( range; 57-79 years ). The navigation time, tourniquet time, blood loss and drainage flow in 48h were observed after the operation. The mechanical axis angle of the lower extremity, the coronal inclination angle of femoral and tibial prostheses and the sagittal inclination angle of femoral prostheses (α,βandγangles ) were measured based on X-rays before the operation and at the 3rd month after the operation. Varus was expressed as positive (+) and valgus negative (-). The knee function was evaluated using the Knee Society Score ( KSS ) before the operation and at the 3rd month after the operation, and the knee joint flexion and extension range of motion ( ROM ) and complications were also recorded. Results The navigation time was ( 10±2 ) min for each knee, and the tourniquet time was ( 93±9 ) min. The blood loss and drainage flow in 48 h were ( 483±55 ) ml. The preoperative and postoperative mechanical axis angles were (+8.07±6.69 ) ° and (+1.20±1.92 ) ° respectively, and statistically significant differences were found between them ( P<0.05 ). The postoperativeαangle,βangle andγangle were ( 89.33±1.64 ) °, ( 89.64±1.47 ) ° and ( 90.86±2.37 ) ° respectively. The KSS scores were ( 86±18 ) points and ( 137±26 ) points respectively before the operation and at the 3rd month after the operation, and statistically significant differences were found between them ( P<0.05 ). The ROM were ( 92±21 ) ° and ( 108±24 ) ° respectively before the operation and at the 3rd month after the operation, and statistically significant differences were found between them ( P<0.05 ). There were no statistically significant correlations between the postoperative mechanical axis angle of the lower extremity,αangle,βangle,γangle and the postoperative KSS and ROM ( P>0.05 ). No complications such as infection, injuries of nerves and blood vessels, bone fractures, deep venous thrombosis of the lower extremity and so on were found. Conclusions The EM navigation system is safe and reliable. With the EM navigation system in TKA, optimal prosthesis position and lower limb alignment and good early clinical results can be achieved.
Keywords：ArthroplastyreplacementSurgerycomputer-assistedElectromagnetic radiationSurgical proceduresoperativeKnee joint
Publication Date：2013-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 396-401 )