Hi, thanks for writing to HCM.
Based on your description, I suspect a Partial Quadriceps tendon rupture in your involved knee.
An xray is needed to diagnose any associated patellar avulsions. Ultrasound
examination or MRI
scan will diagnose the condition.
Partial or incomplete tears are generally managed by nonsurgical measures by Rest, Ice packing, Compression and Limb elevation. The knee joint is immobilized in full extension for 4-6 weeks. Thereafter progressive knee range of motion exercises and quadriceps strengthening exercises are begun.
If conservative management fails, then a surgical reconstruction is indicated.
Hope this information is helpful. Good day