The quads tendon is short for the quadriceps tendon.
The tendon of the quadriceps muscle contains the embedded patella (kneecap) and then the structure continues to the tibia as the patellar tendon.
Extensor mechanism
The whole tendon/patella/muscle complex is called the 'extensor mechanism' because it is responsible for extending the leg.
Synonyms:
Quadriceps tendon
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