Contusions (Bruises)

Mechanism and Symptoms

The contusion can vary in severity due to its size and location, especially in areas with richer blood supply. Most contusions result in some level of pain and discomfort, a result of the release of histamine and other anti-inflammatory chemicals into the spaces between the cells. Generally, the larger the contusion, the more blood is leaked into the intercellular space and the more discomfort is associated with it. Most contusions are self-limiting injuries and respond favorably to rest, ice, compression, and elevation modalities (RICE) immediately after injury.

The spectrum of color changes associated with contusions follow the body's ability to remove the displaced elements of blood from the leaking capillaries. Initially, there is a reddish-blue color from hemoglobin concentrations, which advances to more blue-green hues from the breakdown of hemoglobin to bilirubin in the next week or so. From this, it tends to fade into a golden-brown color with the hemosiderin deposition from iron deposits in the intracellular tissue, finally resuming normal flesh tones.

Minor contusions may take a week or two to resolve, while more serious contusions can take longer. However, there are various contusions that will require more elaborate investigation and management as they can be found in critical tissue areas, such as organs, and can result in permanent disfigurement and dysfunction and sometimes death.

The following is a partial list of organ- and site-specific areas that can present with varied complications and consequences: the retina, ear (wrestler's ear), face, heart, lung, abdomen (liver, spleen, pancreas, intestines), vulva, testicle, bone, rotator cuff, and large muscles, such as the quadriceps, among many others. Several of these will be reviewed here.

Bone Bruises

A bone bruise is the result of blunt force trauma sufficient to disrupt the matrix of the bone just underneath its surface but not sufficient to fracture [Page 322]the entire bone. These injuries are typically associated with increased pain and injuries to adjacent ligaments or tendons. Imaging beyond radiographs, such as computed tomography (CT) and magnetic resonance imaging (MRI), is necessary to confirm bone bruises and also help identify associated injuries to adjacent ligaments or tendons. The natural history of a bone bruise suggests that it is a precursor to early degenerative changes (early arthritis). As such, it is important to delay return to full weight-bearing status in order to prevent further collapse of bone just beneath the surface (subchondral bone) and further aggravation of the lining of the joint spaces (articular cartilage).

Contusions to Large Muscles

Contusions to large muscles such as the quadriceps can result in significant disruption of the muscle belly and, due to its large size, can bleed extensively. One potential adverse complication of a quadriceps contusion is the development of myositis ossificans (heterotopic bone, bone that does not belong there) within the contusion, which can result in prolonged rehabilitation and muscle dysfunction and occasionally requires surgical intervention. The recommendation for this particular injury differs from others in that the knee is immediately placed into a flexed position of 120 and maintained in that position for 24 hours. It is felt that keeping the muscle stretched helps in reducing blood accumulation and also in decreasing contracture. Diagnostic ultrasound investigation of the size and type of echogenicity of the lesion is valuable in predicting the severity of the trauma, with anechoic and low-echogenic lesions taking longer to heal.

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