Knee pain and instability after a sport injury three months ago

Patient: About 3 months ago, I suffered a sports injury in which I landed with my knee locked and hyperextended. X-ray and MRI were negative for breaks, MCL, ACL tears. I have subsequently been doing rigorous physical therapy, focused on strengthening the quad and stretching. 3 months post injury, I am still experiencing strong pain and instability in my knee with exercise, to the point where I can’t practice 5 days a week. The pain occurs when I straighten my knee from a bent position. I feel a sharp pain and a pop medially in the knee cap. Is it expected to feel this type of pain so long after the initial injury, or should I have a doctor re asses my knee?

Doctor: Both ligaments ACL and PCL are very important to stabilize the knee joint backwards and forwards, the lateral ones stab bilize it side to side, the menisci give cushion between femur and tibia, and the synovial fluid lubricates all the surfaces minimizing the friction during the movements, so as you can see every element is important for the correct function of the knee joint. According to the description of your problem, it might be important to rule out also a Meniscus lesion. The menisci are C-shaped wedges of fibro cartilage located between the tibia and femur, and very close related to knee ligaments and attached also to the joint capsule. They are susceptible to get injured with leg rotation movements or rotational forces applied to them, and the lesion produced can be partial or complete tear. Meniscus injuries are common in active people as you, who are involved in sporting or physical activities. Pain along with locking or buckling are common symptoms after a meniscus lesion develops. Locking usually occurs at 20-45° of joint extension. A more reliable indicator of meniscus lesion is a click, pop  or snaps after the joint unlocks, it can be or not associated with pain. On the other hand, knee pain is the most common presentation of patellofemoral syndrome. The pain typically is located behind the kneecap and often shows during activities that require knee flexion and forceful contraction of the quadriceps (ei, during squats, bicycle, ascending/descending stairs, jogging or pendants). Pain may be worsen by sitting with the knee flexed for a long period of time, such as while watching a movie, hence leading to the terms “theatre sign” and “movie-goer’s knee.” The suggested strategy for conservative treatment should be as follows: Physical therapy program (exercises and pain control with TENS, ultrasound, ice packs after exercises), anti-inflammatory medication (i.e.: “Aleve”, “Advil”), education  so  you understand which activities avoid because those can aggravate patellofemoral syndrome. Also, and very important, remark the need for extended adherence to the exercise regimen. The physical therapist should educate you about a home exercise program.