A method for assessing the height of the patella

Abstract

In 150 normal subjects the distance (P) between the upper and lower limits of the articular surface of the patella, and the shortest distance (T) between this same lower limit and the tibial plateau, were measured in standard lateral views of the knee in about 30 degrees of flexion. The limits of confidence of the T/P ratio are shown in the Table. The 5% upper limit of normality of this ratio is 1.11 (one-sided). This method of determining the position of the patella is accurate and more simple than those previously described.

Effect of patient position on measurement of patellar height ratio

“…Blumensaat [7] described the first technique for measuring patellar height in 1938. Since then, several methods [7][8][9][10][11][12][13][14][15] have been proposed; most of these methods utilize patellar height measurements to obtain the ratio of two reference lines and define the normal value as a range of the mean and standard deviation. Due to femoral roll-back and rotation, knee flexion causes of the relationship between the patella and femur to change accordingly.…”

Novel method of measuring patellar height ratio using a distal femoral reference point

“…However, there is no consensus regarding the superiority of any one of these methods [2,10,22]. Most are based on the ratio of patellar length to the distance of the patella from the tibial reference point [5,7,9,12,14,20]. Actually, the patellofemoral joint is defined by the patella's position relative to the distal femur.…”

Evaluation of patella alta using MRI measurements in adolescents

“…[51314] These methods evaluate the patella height indirectly according to various tibial reference points. [15] Numerous studies have compared these measurement methods, and different authors have emphasised the various advantages of the different methods.…”