|Contusions of the trunk may involve the breast, chest wall, abdominal wall, back, hip, buttocks, pelvis, genitals, or pelvic floor (perineum). A contusion is a blunt, compressive injury that does not involve a break in the skin. Contusions cause damage to the skin and underlying soft tissue. Blood seeps out of damaged small blood vessels (capillaries) and collects in the surrounding tissue, forming black-and-blue marks beneath the skin (ecchymosis). After injury, gravity may pull the blood downward so the ecchymosis may extend some distance from the contusion site. Over a period of days, the black and blue will change to green and yellow and eventually fade. The affected area may become swollen and painful. Contusions of the trunk are often the result of a fall, a direct blow from a blunt object, or trauma from a motor vehicle accident.|
Contusions are classified as mild, moderate, or severe. If the contusion is superficial, it involves only the skin and tissue immediately below the skin (subcutaneous tissue). If deep, muscle and bone may also be involved. Blood can accumulate and form a hematoma within the muscle, initiating an inflammatory response that can result in swelling and further tissue injury. Major trauma may cause contusions of internal organs such as the spleen, kidneys, lungs, heart, or brain. Deep contusions are tender and cannot be seen unless superficial contusions accompany them.
The chest wall is particularly vulnerable to contusions because bones (e.g. ribs and clavicles) are close to the skin surface. Collarbone (clavicle) contusions are usually associated with an injury to the breastbone (sternum) or shoulder joint and can cause restricted movement of the chest and shoulder. A breast contusion involves the breast, nipple, and underlying tissues and can occur in both men and women.
The back is also vulnerable to contusions because of the proximity of bone to the skin surface. The shoulder blade (scapula) is at risk because it protrudes slightly with little muscle and fat between the bone and skin. Contusions to the shoulder blade can cause restricted movement of the shoulder. Back contusions occur following a fall or blow by a blunt object.
Areas of the hip and pelvis that are most prone to contusions are the upper tip of the pelvic bone (iliac crest); the lower, front region of the pubic bone (pubic ramus); the upper, outer corner of the thigh bone (greater trochanter); and the lower, rear region of the pelvic bone (ischial tuberosity). A contusion at the iliac crest with formation of a hematoma within the connective tissue covering the bone (periosteum) is called a "hip pointer." Individuals who fall onto the buttocks may incur a contusion at the ischial tuberosity; those who fall on the side or receive a blow from a blunt object may have a contusion at the greater trochanter. Individuals falling forward or receiving a blow from a blunt object may incur a contusion at the iliac crest. Contusions at the pubic ramus may occur if an individual falls across a bar (e.g., gymnastics). Injuries to the buttocks can affect the sciatic nerve.
Contusions are one of the most common hip and pelvis injuries sustained by the elderly and by athletes. Perineal contusions are caused by a fall or a direct blow to the floor of the pelvis and are often associated with genital contusions.
Risk: Individuals at greatest risk for contusions of the trunk (especially back, chest or abdominal wall injuries) include workers who do manual labor or are physically active, those who participate in high-impact or contact sports (e.g., football, ice hockey, basketball, softball, baseball, soccer, wrestling and boxing) Risk is higher if protective equipment is not worn. Individuals at higher risk of buttock contusions are those at risk for falls (elderly, obese, gait/balance impairments), those who participate in contact sports (football, basketball, ice hockey, and baseball), and sports with the potential for falling from a height (horseback riding, pole-vaulting, high-jumping, gymnastics, or skating. Individuals at increased risk of sustaining perineal and/or genital contusions include those participating in ice-skating, cycling, gymnastics, and horseback riding.
Risk is also increased in individuals who have a bleeding disorder (e.g., hemophilia) or other blood dyscrasia that may interfere with normal coagulation (e.g., idiopathic thrombocytopenia purpura [ITP], thrombocytopenia or leukemia); a vitamin deficiency; those who are obese; or who take aspirin or anticoagulants regularly.
Incidence and Prevalence: Contusions are very common. Most contusions go unreported and untreated so overall incidence is not known.