Patella position versus length of hamstring muscles in children

The results of ultrasonographic examinations of the patellar height in the knee joints in children was subjected to analysis. The study aimed at the s pecification of a norm of patellar height in the developmental age, based o n the tendon-patellar coefficient (analogous to the radiologic measurement according to Insall and Salvati). The results of ultrasonographic and clini cal examinations of 114 knee joints performed in 57 healthy children were u sed for the study. The average value of the tendon-patellar coefficient was 1.2 and was independent of age or sex. A statistically significant depende nce of the coefficient on the popliteal angle was demonstrated, which indir ectly proved the dependence of the coefficient on the length of the hamstri ngs. In our opinion, the use of ultrasonographic tendon-patellar coefficien t allows the differentiation of the so-called physiologic shortening of ham strings from its pathologic form.