The authors investigated the statistical relationship and significance between the transverse and sagittal plane proximal articular set angles both radiographically and intraoperatively. The analysis revealed a highly significant difference between the means of the respective measurements. Although the radiographic and intraoperative findings were found to be related for the transverse plane proximal articular set angle, the transverse plane PASA was approximately 7 degrees greater when measured intraoperatively. The concept of a sagittal plane PASA was also introduced. The significance of accurate measurements in the surgical correction of hallux valgus was also examined.