膝しつ蓋がい腱けん

し

つ

が

い

け

ん

Meanings

1

noun

patellar tendon

Anatomical term for the tendon connecting the patella to the tibia.

蓋cover, lid, flap

腱tendon

膝しつ蓋がい骨こつ
膝蓋骨 is the patella (kneecap) itself, while 膝蓋腱 is the tendon attached to it.
アキレス腱けん
アキレス腱 is the Achilles tendon at the back of the ankle, whereas 膝蓋腱 is at the front of the knee.

Compound of 膝蓋 (しつがい, 'patella') and 腱 (けん, 'tendon'). The reading is on'yomi.