Mark McGwire, First Base for the St. Louis Cardinals

NAME: Mark McGwire
TEAM: St. Louis Cardinals
POSITION: First base
INJURY: Strained back

OTHER ATHLETES AFFECTED

Basketball: Toni Kukoc, Philadelphia 76ers; Zan Tabak, Indiana Pacers; Baseball: Jaret Wright, Cleveland Indians; Pedro Martinez, Boston Red Sox

PLAYER BIO

Mark McGwire is most famous for shattering Roger Maris' home run record of 61 homers in a season when he hit 70 in 1998. He followed up that season by hitting 65 home runs in 1999 and also hit his 500^th career home run. At 36, he is in his 15^th major league season; he played 12 seasons for the Oakland Athletics and has been with the Cardinals for three seasons. While in Oakland, McGwire teamed up with José Canseco to form the "Bash Brothers." In college, he set the Pac-10 conference single-season record with 32 home runs. He also played on the 1984 U.S. Olympic baseball team.

HOW IT HAPPENED

Over the course of spring training, McGwire developed some pain and discomfort in his back and, when the pain did not quickly subside, he had his back examined. He sat out a few games and rested the back as best he could, but mild pain persisted. On April 15, McGwire was again examined, and it was feared that he might have suffered a disc injury, but tests were negative. He has since returned to limited, then normal, action and playing time. McGwire explained the situation, "When you look at the long haul of the season and you think it's probably going to be bothersome all year, then [you] want to take time to get it done and taken care of."

WHAT IS A STRAINED BACK?

A strained back is the aggravation and inflammation of muscles and tendons in the back. It may be caused by overuse or repetitive strain, improper stretching, or pulling the muscles during one particular motion. The particular muscles affected are the paravertebral muscles that are found on either side of the spine in the lower back. The muscles are used during everyday events such as walking or sitting down, but are especially strained during lifting. For a baseball player, the area is further strained by batting. During the motion of swinging the bat, the player quickly twists or wrenches his back. The injury is age- and weight-related. Athletes are far more likely to strain back muscles as they grow older. But strained backs are not limited to athletes. Many people strain back muscles while lifting heavy boxes or participating in sports, as they grow older.

DIAGNOSIS

Back injuries are diagnosed using clinical exam. They are most often detected when athletes complain of soreness, pain, and tightness in the back. Typical strains include mild pain and almost constant discomfort. Tests such as X-rays may be used to distinguish muscular strains from bone problems, and an MRI or CAT scan may confirm the existence and severity of the injury.