The articularis genu is a small muscle arising from the deep surface of the vastus intermedius and inserting into the suprapatellar pouch, acting as a dynamic suprapatellar pouch retractor during knee extension. Without it, the synovial pouch would impinge between the quadriceps and the femoral trochlea. It is the muscle responsible for the suprapatellar plica syndrome when the plica — a remnant of the fetal synovial septum — persists and becomes symptomatic.
| Origin | Anterior distal femoral shaft (deep surface of the vastus intermedius) |
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| Insertion | Suprapatellar bursa and proximal patellar reflection — pulls the synovial pouch proximally during knee extension |
| Nerve Supply | Femoral nerve (L2, L3, L4) |
| Blood Supply | Lateral circumflex femoral artery |
| Actions | Pulls the suprapatellar pouch proximally during knee extension to prevent impingement between the suprapatellar synovium and the patellofemoral joint |
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The articularis genu's insertion on the suprapatellar pouch means that scarring of the VI-articularis complex after distal femur fracture or surgery obliterates the suprapatellar pouch, producing profound knee flexion restriction. Arthroscopic resection of the obliterated suprapatellar fat and articularis adhesions is required for severe post-operative stiffness.
Not palpable as a separate structure from the vastus intermedius.
Articularis genu scarring after distal femur surgery producing suprapatellar impingement and knee stiffness managed with arthroscopic pouch restoration.
