Quadriceps Tendon Rupture

The fat-saturated T2-weighted image above shows absence of expected low signal in the location of the quadriceps tendon, and high signal filling the gap. The appearance is consistent with tendon rupture.
The normal quadriceps tendon is made up from contibutions from all four muscles, and classically has a trilaminar appearance:
* Superficial layer: rectus femoris
* Middle layer: vastus medialis, vastus lateralis
* Deep layer: vastus intermedius
Rupture is usually associated with forced flexion of the knee, or a direct blow, although spontaneous ruptures are reported. Predisposing illnesses include: connective tissue disorders (SLE, RA), gout, renal impairment and corticosteroid use.
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Reference: Resnick - Bone and Joint imaging.
Credit: Dr Frank Gaillard
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