Explosive or sudden movement can cause your hamstring to rupture at either the knee or where it attaches to the pelvis. Most typically, the rupture occurs at the knee where the tendons attach at the back of the knee. Surgical intervention and physical therapy, or a combination of both, can heal the rupture.
Pain
If you've ruptured your hamstring, you will feel sudden pain at the back of your knee or thigh. The pain will be sharp and intense, typically occurring just after the rupture because of sudden movement.
Swelling
The back of the thigh will swell from a ruptured hamstring. This is sometimes accompanied by the area of the rupture becoming hot to the touch and feeling tender. You will likely see a knot where the rupture occurred, and the spot of the rupture will be extremely uncomfortable to touch.
Bruising
The back of the thigh could bruise considerably in the general area of the rupture because of the blood released during the rupture into the area surrounding it.
Inability to Stand
If your leg cannot bear your weight, you have a symptom of a hamstring rupture. The muscle is no longer properly attached to your skeletal frame and cannot provide appropriate support.
Inability to Bend Knee
Being unable to bend your knee is another symptom of a ruptured hamstring. The muscles can't contract properly to support movement of the knee joint. Similarly, if pressing against something while bending your knee causes pain, it could be a hamstring tear or full rupture.
What to Do
Hamstring ruptures are significant injuries. A study by Drs. Cohen and Bradley published in the June 2007 "Journal of the American Academy of Orthopaedic Surgeons" notes that surgery is the best, most complete option to heal the rupture. The study observes that patients who did not undergo surgery to repair the rupture often had side effects of muscle weakness and problems with sciatica in the long term. New surgical techniques make surgery an effective option for most patients.
