Fig. 1From: Determination of reference values and frequency of occurrence of patella alta in German shepherd dogs: a retrospective studyMedio-lateral radiograph of the stifle joint. The lines show measurements of the patellar length (PL) and patellar ligament length (PLLj) according to [2]. The measurements are used to calculate the Insall–Salvati ratio (PLLj/PL). The patellar ligament length is measured from the most distal part of the patella to the small indentation on the tibial tuberosityBack to article page