Football is a contact sport, with a high risk of injury. Knee, ankle, and head injuries, such as concussions, are the most common types of football injuries. However, despite being well padded, the anterior (front) thigh is a commonly injured part of the body.

Quadriceps contusion
Football is considered by many to be a "bone-bruising" sport. For the most part, this is very true. The quadriceps muscles (four muscles comprising the front of the thigh) (Fig. 1) are particularly susceptible to contusions (bruising). A quadriceps, or quad, contusion is literally a deep bruise of the muscle(s) of the thigh closest to the femur (thigh) bone. As a result, scar tissue can form and restrict muscle function. Symptoms of thigh contusions include pain, swelling, limping, and loss of knee motion.

Mechanism of injury
Thigh contusions are a result of direct blunt trauma. This refers to sudden forceful injury caused by a blunt object, such as a helmet or shoulder pad. This injury creates a force that is transmitted through the substance of the muscle. The damage, however, usually occurs in the layer closest to the bone. The quadriceps muscles are in contact with bone throughout the length of the thigh, and thus, are especially vulnerable. The muscle damage sustained can be either minor (involving only swelling on a cellular level) or major (involving rupture of the capillaries and leading to heavy bleeding). Heavy bleeding can prolong symptoms and delay your return to play.

Myositis ossificans (heterotopic ossification)
Quad contusions can lead to a complication called myositis ossificans. Myositis ossificans literally means inflammation of muscle leading to bone formation. Heterotopic ossification means formation of bone in an unusual or peculiar place (Figs. 2 & 3). Myositis ossificans has been reported in 9% to 20% of all cases of quad contusions. When the quadriceps muscles bleed, a cascade of cellular responses can occur, causing heterotopic bone formation. The usually elastic, contractible components of the muscle become rigid. Some studies have identified the following risk factors for the development of myositis ossificans: 1) limited knee range of motion, 2) previous quad contusion, 3) treatment for a quad contusion that was delayed more than 72 hours, 4) knee effusion (swollen knee), and 5) injury sustained by playing football.

Treatment goals
The treatment plan should include limiting swelling and bleeding; minimizing the amount of scar formation; and preserving the elasticity, contractility, and strength of the injured and uninjured muscle tissue.

Return to play
Athletes may return to non-contact participation when there is 120 degrees of pain-free active knee motion. Full participation may occur when the athlete has full range of motion and 90% of contralateral (opposite) leg strength, usually within 1 to 2 weeks. Upon return to contact sports after a quad contusion, the athlete should have the basic thigh pad modified with a ring-shaped pad to prevent further injury.

Hip pointer
Another injury of the anterior thigh (known as a hip pointer) occurs at the level of the hip or pelvis. The rectus femoris (one of the quadriceps muscles) and the abdominal muscles attach to a bone called the ilium. The abdominal muscles attach to a part of the ilium called the iliac crest. A hip pointer results from either a contusion to the iliac crest or from a separation of the muscle fibers from the iliac crest (click here for Fig. 4). Symptoms include pain, tenderness, and difficulty walking.

Mechanism of injury
Like thigh contusions, a hip pointer usually results from a direct blow. A severe hip pointer can occur after a significant stretch injury that leads to tearing of the muscle fiber insertions at the iliac crest.

Management
Hip pointers should be treated early to minimize prolonged impairment. If your physician is suspicious of a fracture or avulsion (separation of the muscle from the bone), x-rays may be obtained (Fig. 5). This is especially important for younger athletes who may still be growing.

Return to play
Return to play is generally permitted once pain is tolerated and gait (walking) has returned to normal. Protective hip pads are helpful and recommended.

Like most debilitating injuries, it is important that you give yourself time to heal. Jumping back into the thick of things can make your condition worse than it already is. Remember, quadriceps contusions and hip pointers are not limited to football. So, be sure to follow your physician's suggestions and take the necessary preventive measures to ensure a safe return and healthy return to normal activities and sports.

Reuben Sloan, M.D.
Columbus, Georgia