A thigh bruise, medically known as a quadriceps contusion and commonly called a dead leg, is an injury to the quadriceps muscles that causes damage to the muscle fibers and bleeding within the thigh.
The quadriceps muscle group consists of four large and powerful muscles that run down the front and sides of the thigh: the vastus medialis, vastus intermedius, vastus lateralis, and the rectus femoris. At each end of the muscles are tendons, strong cords of connective tissue. Tendon fibers begin within the muscle fibers and extend to the bones where they have their attachments. The quadriceps originate at the ilium (located at the upper edge of the pelvis) and the femur (thighbone). At their lower ends their respective tendons join together into one quadriceps tendon that surrounds the patella (kneecap). The tendon then becomes known as the patellar tendon, which inserts into the tibia (shinbone). The quadriceps are responsible for flexing (bending) the hip, straightening the leg at the knee, and are used in nearly every movement of the legs.
Damage to the quadriceps can cause bleeding, the severity of which depends on the force of the injury. Bleeding can be either intramuscular, which means that the bleeding is contained within the muscle compartment, or intermuscular, where the blood escapes from the fascia (sheath of tissue) that surrounds the muscle and flows downward within the leg, between the muscle compartments. Intermuscular bleeding is less severe. Intramuscular bleeding can be serious as the blood, trapped within the fascia, increases pressure within the muscle compartment. This can lead to the development of compartment syndrome, which causes muscle and nerve damage and impaired blood flow that can result in the death of leg tissue in the injured area.
An external blow to the front of the leg is the normal cause of a thigh bruise. The impact crushes the muscle against the femur. These injuries often occur during sporting activity, such as playing football, basketball, soccer or rugby, when a player receives a kick to the thigh, or is hit with a piece of sporting equipment, such as a bat.
The severity of the symptoms will depend on the force behind the blow, but will likely include the following:
- Sudden pain, which may be severe, at the moment of injury
- Bruising, which may travel down the leg
- Inability to fully bend or straighten the knee
- Inability to place full weight on the leg
- Stiffness, made worse if the athlete continues to play after injury
The doctor will ask about the circumstances of the injury, and physically examine the thigh. If it is an older injury and ossification is suspected, X-rays might be taken.
It is extremely important to treat a thigh bruise properly as, without such treatment, blood can form pools in the damaged muscle that calcifies, or hardens, with time, resulting in stiffness and lumps within the muscle. This condition, known as osteomyositis ossificans, sometimes needs remedial surgery.
Regardless of whether bleeding from a quadriceps contusion is intra- or intermuscular, initial treatment should be the same. An ice pack should be placed on the thigh immediately. If no ice pack is available, one can be made by placing ice in a bag and crushing it. The bag should be wrapped in a towel before placing it against the skin.
The knee should be fully flexed (bent) when the leg is iced. If the knee is straight when the leg is first iced, stiffness in the leg the following day will be markedly worse. If the knee is flexed, the quadriceps will remain much more flexible. Icing can be repeated for as long as is comfortable, every two hours for the first two days following injury. Between each icing the leg should be kept wrapped in a compression bandage.
Crutches can be used to aid mobility. To minimize swelling, the patient should keep the leg elevated above the level of the heart, as often as possible. This is best achieved by lying on the back with the leg resting on a pile of pillows.
NSAIDs (non-steroidal anti-inflammatory drugs) such as ibuprofen (Advil), naproxen (Aleve), or aspirin can be taken, according to direction, to reduce pain and alleviate inflammation.
Physical therapy might include instruction on proper rehabilitation techniques, ultrasound, and electrical stimulation to promote healing.
After the acute stage of the injury, which is the first two or three days, gentle rehabilitation of the quadriceps can begin. It is important not to cause any pain when exercising. If pain is felt, the patient is doing too much and recovery time will be lengthened. Damaged muscle fibers need to be allowed to heal properly.
Sitting on the floor with the injured leg straight out in front and the unaffected leg bent with the foot on the floor, contract the thigh muscles of the injured leg (the quadriceps) by pressing the knee towards the floor. Hold the position for 5-10 seconds then relax. Repeat 10 times, 3 times a day.
Lying on your back, bend the injured knee and keep the foot on the floor. Slide the heel towards the buttocks as far as you can without pain. Repeat 10-20 times.
Straight leg raise:
Lying with the back on the floor, bend the unaffected knee and rest the foot on the floor. Keeping the knee of the injured leg straight, contract the thigh muscles and lift the leg up until the heel is about 6 inches off the ground. Hold for 5-10 seconds then relax. Repeat 10 times, 3 times a day.
Quad stretch 1:
Lie on the floor on the stomach, with the injured leg on a pillow. Slowly bend the knee until a gentle stretch is felt. Hold the stretch 30-60 seconds. Repeat 10 times, 3 times a day.
Quad stretch 2:
Using a wall for support, hold the right foot with the right hand and gently pull the foot up and behind, towards the buttocks, stopping when you feel a gentle stretch. Keep the knees together and the pelvis neutral (neither tilted forwards nor backwards). Hold the stretch for 10 seconds then relax. Switch legs and repeat exercise.
As a thigh bruise is an accidental injury, there is little to be done to prevent it occurring. However, if the patient is returning to contact sports, padding can be worn over the thigh to protect the quadriceps muscles.