Femorotibial relationship changes as the posture changes from patellae-forward stance to preferred toe-out stance

• Published in: Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association Vol. 20; no. 1; pp. 143 - 148
• Main Authors: Noh, Jung Ho, Kyung Bae, Dae, Yoon, Kyoung Ho, Jun Song, Sang, Roh, Young Hak, Ryu, Chang Hyun
• Format: Journal Article
• Language: English
• Published: Tokyo Elsevier B.V 01.01.2015; Springer Japan; Springer Nature B.V
• Subjects: Adult; Femur - diagnostic imaging; Humans; Knee Joint - diagnostic imaging; Lower Extremity; Male; Medicine; Medicine & Public Health; Original Article; Orthopedics; Posture; Radiography; Range of Motion, Articular; Reference Values; Rheumatology; Tibia - diagnostic imaging; Young Adult; Limb Alignment; Proximal Tibia; Image Intensifier; Mechanical Axis; Tibial Rotation
• ISSN: 0949-2658; 1436-2023
• DOI: 10.1007/s00776-014-0668-2

BackgroundFull-length standing anteroposterior radiograph is a standard protocol to evaluate the lower limb alignment in frontal plane. However, most people tend to stand or walk with feet pointing outward. The purpose of this study is to assess the femorotibial relationship as the posture changes from patellae-forward stance for the conventional technique of a full-length standing anteroposterior radiograph to a toe-out quiet stance using a fluoroscope. MethodsFemoral and tibial rotation and femorotibial rotation were measured in 60 healthy lower limbs usingfluoroscopy during postural change from patellae-forward stance to toe-out quiet stance. ResultsThe average toe-out angle was 21.4°. The average femoral, tibial, and femorotibial rotations duringpostural change were 6.1°, 4.0°, and 2.1°, respectively (p = 0.000). The correlation coefficient for femoral and tibial rotation was 0.747 (p = 0.000). The correlation coefficient for femoral and femorotibial rotation was 0.670 (p = 0.000), and for tibial and femorotibial rotation was 0.006 (p = 0.962). The correlation between toe-out angle and femorotibial rotation was statistically significant (r2 = 0.096, p = 0.016). The correlations between toe-out angle and femoral rotation, and between toe-out angle and tibial rotation were not statistically significant (r2 = 0.047, p = 0.095, and r2 = 0.000, p = 0.9, respectively). ConclusionsThe subject’s posture significantly affects the femorotibial relationship. When a subject changesposture from a patellae-forward stance to a toe-out quiet stance, the femur rotates internally on the tibia. Level of evidence Diagnostic, level II.