Intraoperative Fluoroscopic Assessment of Limb Alignment is a Reliable Predictor for Postoperative Limb Alignment in Biplanar Medial Opening-Wedge High Tibial Osteotomy.
The purpose of this study was to assess the reliability of pre-, intra operative, and postoperative limb alignment measurements and investigate the correlation between the measurements in biplanar medial opening-wedge high tibial osteotomy.



This study enrolled 59 knees undergoing biplanar opening-wedge high tibial osteotomy for primary medial osteoarthritis with varus deformity. Preoperative and postoperative standing lower leg radiographs and intraoperative fluoroscopic images were taken. Two independent examiners analyzed the radiologic data to assess lower limb alignment and mechanical axis (MA) deviation (percentage of MA position on tibial plateau). The effect of preoperative hip-knee-ankle angle and MA deviation, age, sex, body mass index (BMI), and joint line convergence angle on the discrepancy between intraoperative and postoperative MA deviation was analyzed.



The mean preoperative hip-knee-ankle angle and MA deviation were varus 7.7 ± 3.3° and 14.1 ± 15.1%, respectively. After osteotomy, the mean intraoperative postosteotomy MA deviation was 57.9 ± 2.1% in supine position, and the mean post-operative MA deviation increased to 63.9 ± 2.9% on standing radiographs. The mean difference between intraoperative postosteotomy MA deviation and postoperative MA deviation was 6.1 ± 2.2%. Linear regression analysis between intraoperative postosteotomy MA deviation and postoperative MA deviation showed a statistically significant linear relationship (R2= 0.449; P < .001). Multivariate regression analysis revealed that preoperative joint line convergence angle (β = 0.856; P < .001) and BMI (β = 0.349; P < .001) were significant positive predictors for the difference in MA deviation.



There was a significant linear relationship between intraoperative postosteotomy MA deviation and postoperative MA deviation following biplanar medial opening-wedge high tibial osteotomy. A greater discrepancy between MA deviations was significantly associated with higher BMI and joint line convergence angle.
Department of Orthopaedic Surgery, Anam Hospital, Korea University College of Medicine, Seoul, South Korea.
Ki-Mo
KM
Jang
Department of Orthopaedic Surgery, Anam Hospital, Korea University College of Medicine, Seoul, South Korea.
Jong-Hee
JH
Lee
Department of Orthopaedic Surgery, Anam Hospital, Korea University College of Medicine, Seoul, South Korea.
Il Youp
IY
Cho
Department of Orthopaedic Surgery, Anam Hospital, Korea University College of Medicine, Seoul, South Korea.
Bong-Kyung
BK
Park
Department of Orthopaedic Surgery, Anam Hospital, Korea University College of Medicine, Seoul, South Korea.
Seung-Beom
SB
Han
D000328:Adult; D000368:Aged; D000843:Ankle Joint; D005260:Female; D005471:Fluoroscopy / Q000706:statistics & numerical data*; D006801:Humans; D007717:Knee; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D035002:Lower Extremity; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010027:Osteotomy / Q000706:statistics & numerical data*; D011184:Postoperative Period; D011187:Posture; D011446:Prospective Studies; D011859:Radiography; D015203:Reproducibility of Results; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery*
high tibial osteotomy; intraoperative lower limb alignment; knee joint; medial compartmental osteoarthritis; postoperative lower limb alignment