We aimed to investigate whether the anterior superior iliac spine could provide consistent rotational landmark of the tibial component during mobile-bearing medial unicompartmental knee arthroplasty (UKA) using computed tomography (CT). During sagittal tibial resection, we utilized the ASIS as a rotational landmark. In 47 knees that underwent postoperative CT scans after medial UKA, the tibial component position was assessed by drawing a line tangential to the lateral wall of the tibial component. Rotation of the tibial component was measured using two reference lines: a line perpendicular to the posterior cortical rim of the tibia (angle α) and Akagi's line (angle β). Instant bearing position and posterior cruciate ligament fossa involvement were also evaluated. External rotation of the tibial component relative to each reference line and external rotation of the bearing relative to the lateral wall of the tibial component were considered positive values.Purpose
Methods
Routine examination for spinal deformity as part of a school health screening programme was introduced in Singapore in 1981. The three different ethnic groups included in the study provided figures for the prevalence of idiopathic scoliosis in an Asian population. A three-tier system of examination was used and a total of 110744 children in three age groups were studied. In those aged 6 to 7 years the prevalence was 0.12%. The prevalence in those aged 11 to 12 years was 1.7% for girls and 0.4% for boys, a ratio of 3.2 to 1. In girls aged 16 to 17 years the prevalence was 3.1%. In the latter two age groups there was a significantly higher prevalence in Chinese girls as compared with Malay and Indian girls. The optimal age for school screening seemed to be 11 to 12 years, but repeated examinations may be worthwhile.