Why the switch to metal?
The suit touches on a hotly disputed issue that has been roiling youth and scholastic baseball programs for years.

In 2003, Brandon Patch, an 18-year-old pitcher for an American Legion team in Helena, Mont., was hit in the head by a line drive off an aluminum bat and died several hours later. In Pennsylvania, 15-year-old Donald Bennett was struck in the face by a line drive from a metal bat while pitching in a 2001 game, causing him to lose an eye.

New York City and North Dakota have banned metal bats for youth and school sports, and New Jersey is considering a similar ban.

Several states are studying the issue. Pennsylvania rejected a proposed ban, and Massachusetts did likewise last year — two months after a high school freshman throwing batting practice was hit in the head by a line drive that fractured his skull. He survived and is expected to make a full recovery.

The National Federation of State High School Associations lets its members choose whether to use metal or wood; most colleges use metal bats.

Metal bats are priced at as much as $300 but are considered more cost-effective than wood bats — which sell for under $100 — because they are far less likely to break and can last for years.

Domalewski was playing in a Police Athletic League game, but Little League was sued because the group certifies that specific metal bats are approved for — and safe for — use in games involving children.

Little League reached an agreement with the major manufacturers of metal bats in the early 1990s to limit the performance of metal bats to that of the best wooden bats. On its Web site, the league said injuries to its pitchers fell from 145 a year before the accord was reached to the current level of about 20 to 30 annually.

The league said that since it started keeping records in the 1960s, eight players were killed by batted balls, six of which were hit by wooden bats. The two metal bat fatalities occurred in 1971 and 1973, before the new standards were adopted.

Mike Ehrmann / Getty Images The Week in Sports Pictures The nation grieved for those hurt, killed and affected by the Boston Marathon bombings. After one of the suspects was caught on Friday — following a day-long lockdown and manhunt — sports returned to Boston over the weekend.

In 2002, the U.S. Consumer Safety Product Commission ruled that there was inconclusive data to support a ban on metal bats in youth and high school baseball games. Its own study found that from 1991 to 2001, there were 17 deaths nationwide because of batted balls — eight from metal, two from wood, and another seven of unknown origin.

Joseph and Nancy Domalewski pray that their son will return to what he was before the injury. But no doctor has told them that is likely.

"I miss my boy, the way he was,'' his mother said. "You can't take away our hope.''

"We describe our days as painful, and somewhat less painful,'' his father added. "Our hope is that he walks and talks and becomes a functioning member of society and has kids.''

The Domalewskis have purposely left unfixed the arrow hole that Steven made in the basement.

"We're saving that for him to spackle when he gets better,'' his father said.