Lower-Limb Alignment and Posterior Tibial Slope in Pakistanis: A Radiographic Study

Abstract

Knee alignment and geometry vary in different population subsets. With regard to total knee arthroplasty, the more medially inclined angle J in Pakistani men suggests that an anteroposterior cut of the distal femur should be in increased external rotation, compared with Pakistani women. Whereas the greater posterior tibial slope in Pakistanis suggests that a proximal tibial cut with a greater posterior tibial slope may reduce the chance of tibial loosening and increase postoperative knee range of motion, especially when using posterior cruciate ligament-retaining designs.

Femoral Lateral Bowing and Varus Condylar Orientation Are Prevalent and Affect Axial Alignment of TKA in Koreans

“…However, it is not feasible to compare our findings directly with those of previous studies because of differences in age and sex compositions of populations studied, the types of parameters measured, and the types of variables reported [11,16,26,29,30,36,38,40]. Nonetheless, it appears that like the Korean female patients in this study, Asian (Chinese, Indian, and Japanese) patients undergoing TKA for medial osteoarthritis commonly exhibit lateral femoral bowing and varus condylar orientation and a larger tibial plateau inclination than healthy Western subjects (Table 7) [11,26,29,30,36,40].…”

“…This 3°of varus inclination of the tibial plateau and approximately the same degree of valgus orientation of the distal femoral condyle have been viewed as basic in past anatomical studies [11,26] and as the norm to achieve proper coronal alignment using most TKA instrumentation systems. However, several authors have reported considerable variations in normal alignment between ethnicities [16,29,30,36,40]. Furthermore, several Asian studies have found femoral lateral bowing and obliquity of the proximal tibial joint surface in knees with advanced osteoarthritis can present with more severe varus inclination ([ 3°) [16,29,30,36,40].…”

“…However, several authors have reported considerable variations in normal alignment between ethnicities [16,29,30,36,40]. Furthermore, several Asian studies have found femoral lateral bowing and obliquity of the proximal tibial joint surface in knees with advanced osteoarthritis can present with more severe varus inclination ([ 3°) [16,29,30,36,40]. In addition, we have observed the femora in these patients frequently have lateral bowing of the shaft and varus orientation at the condyles and the tibiae exhibit a much larger varus inclination at the plateaus in Koreans.…”

Factors contributing to inherent varus alignment of lower limb in normal Asian adults: Role of tibial plateau inclination

“…Tang et al [9] in an analysis of 50 normal Chinese adults have reported a mean mechanical alignment of 177.8°or 2.2°varus. In a similar study involving 59 normal Pakistani adults, Khattak et al [10] have reported a mean mechanical alignment of 178.9°or 1.1°varus. However, both these studies have not analysed variations in normal mechanical alignment and the factors which may contribute to this variation.…”

Correlation of posterior tibial slope with metaphysiodiaphyseal angle in total knee arthroplasty: A radiological study

“…Almost all studies in this field have been done in the Caucasian population. Studies done in the Chinese, Japanese, and Pakistani populations (Asians) have documented a difference in the PTS in their respective population from the Caucasians 6–8. Considering these racial differences in the anatomy of the knee, the postoperative outcome and the need for a difference in the prosthesis according to racial variations, a study was needed to bring out the characteristics of Indian population, which would help in designing prosthesis suited for Indian population.…”