Postoperative knee flexion is an important indicator of success in total knee arthroplasty (TKA). Factors influencing the postoperative range of motion (ROM) were reported to be preoperative ROM, primary indication, height of postoperative joint line, patellar thickness, postoperative pain and rehabilitation. In this study, we aimed to identify the relationship between preoperative hip ROMs and postoperative knee flexion through reviewing the TKA results in Japanese patients. We retrospectively reviewed primary TKAs 55 knees in 55 patients (33 left and 22 right) between April 2012 and March 2013 inclusive. The patients were 11 men and 44 women, with a mean age of 76.7 years. Preoperative hip ROMs and perioperative knee flexion were measured by using goniometer. Hip ROMs were flexion, extension, abduction, adduction, external rotation; ER, internal rotation; IR and total rotation; TR (The total rotation added up ER and IR.). Hip ROMs were measured passively, with the pelvis was fixed manually. Postoperative knee flexion was measured in the fourth week. The patients were classified according to the good group (28 knees), the postoperative knee flexion was more than 125 degrees; and the poor group (27 knees), less than 120 degrees. We compared preoperative hip ROMs in each groups. Multiple regression analysis and Single regression analysis were used for comparison between preoperative hip ROMs and postoperative knee flexion. For comparisons between paired groups we used Wilcoxon test, between unpaired groups Mann-Whitney U test. A p value of less than 0.05 was considered significant.Introduction
Patients & Methods
