Devastating concussions short-circuited Eric Lindros's NHL career.
Injuries are a major part of hockey.
General managers have to construct a roster that will allow a coach to deal with a key injury and still make progress.
But that's often very difficult when a player suffers an absolutely devastating injury.
A number of NHL players who have suffered overwhelming injuries were never able to return to top form when they came back.
In this piece, we look at seven of them.
Cam Neely was a solid prospect when the Bruins acquired him from the Vancouver Canucks prior to the 1986-87 season.
Once Neely pulled on his Bruins' uniform, he became one of the most explosive power forwards in the NHL. Neely was a dominant goalscorer and one of the best fighters in the league. He scored 36, 42 and 37 goals in his first three seasons in Boston.
Neely took his game to another level in 1989-90, scoring 55 goals, and he followed that up with 51 goals the following year.
Neely was flying high, and when the Bruins met the Pittsburgh Penguins in the 1991 Eastern Conference Finals, the Bruins won the first two games of that series. In the third game, the series turned around when Penguins defenseman Ulf Samuelsson hit Neely above the knee and knocked him out of the series.
Specifically, Samuelsson's knee hit Neely's thigh (source: SI.com). The damage to the muscle was so bad that it started to calcify. Additional cartilage damage attributed to the blow kept Neely on the sidelines.
Neely played just 22 games over the next two seasons. However, when he came back in 1993-94, Neely was explosive. He scored 50 goals in 49 games for the Bruins.
However, the pain of the injury caused him to miss about 40 percent of the games on the schedule. He played two more seasons, but he never played as many as 50 games after that.
Eric Lindros came into the NHL as a controversial figure.
Lindros was the No. 1 pick of the late, lamented Quebec Nordiques in 1991 but the big center refused to consider the idea of playing for the team. His rights were ultimately traded to the Philadelphia Flyers.
Lindros became a star for the Flyers, but he never quite lived up to the expectation that he would become a truly dominant player.
His days as an elite player came to an end when he suffered a devastating concussion at the hands of New Jersey Devils defenseman Scott Stevens (video above).
Lindros was skating over the blue line when he was hit in the upper body by the powerful Stevens. Lindros played five more seasons but never reached the same level of productivity.
Pat LaFontaine was a star player for the New York Islanders and Buffalo Sabres throughout the 1980s and 1990s.
LaFontaine suffered his first concussion 1990 when he was hit by James Patrick of the New York Rangers in a playoff game (source: New York Times).
LaFontaine told the New York Times that he also suffered a concussion in every season that followed through 1996-97.
After that last concussion, LaFontaine played two more seasons, but he could not match his previous level of productivity.
Charlie Simmer played left wing for the Los Angeles Kings on the legendary "Triple Crown" line.
Playing alongside Marcel Dionne and Dave Taylor, Simmer became a powerful goalscorer who could dominate in the slot.
Simmer scored 56 goals in the 1979-80 season for the Kings and matched that total by the 65th game of the 1980-81 season.
However, he suffered a broken leg in that game against the Toronto Maple Leafs. Simmer had to be wheeled off the ice at Maple Leaf Gardens.
Simmer would play several more seasons with the Kings, Boston Bruins and the Pittsburgh Penguins, but he was never the scorer that he had been in the past.
Joe Nieuwendyk is a Hall of Fame player who played the best part of his career with the Calgary Flames and Dallas Stars.
Nieuwendyk was a dominating offensive player who could rip the puck into the net with ease and find his open teammates with pinpoint passes.
Nieuwendyk tore his ACL after he was checked into the boards by San Jose's Bryan Marchment in the 1998 playoffs.
Nieuwendyk would return from the injury, but he was never quite the same player again.
He scored 30 goals or more eight times prior to that injury, but he never reached that level again, despite playing eight more years.
Bernie Parent had a Hall of Fame career with the Philadelphia Flyers.
When the Flyers won the Stanley Cup in 1974 and '75, they received superb goaltending from Parent every step of the way.
Parent won the Conn Smythe and Vezina Trophies in both seasons.
Parent would continue to be one of the top goalies in the NHL for years, but his career came to an abrupt end when he took a stick to the eye in a game against the New York Rangers (video above).
Parent suffered a torn retina and was never able to regain his depth perception after the injury. He never played another NHL game (source: GreatestHockeyLegends.com).
Ted Green was a rough, hard-nosed defenseman for the Boston Bruins in the 1960s.
As the team was coming of age and becoming the legendary "Big, Bad Bruins" who loved to score goals in bunches and beat opponents down with their fists, Green was one of the team's most pugnacious players.
"Terrible Ted" was more than willing to drop his gloves and engage with opponents. In a 1969 preseason game with the St. Louis Blues, Green and St. Louis defenseman Wayne Maki took their fight to a new level.
They used their sticks as weapons, and each went after the other's head. Maki hit Green with a two-hander (above) and Green was nearly killed as a result of the blow. He suffered a skull fracture and missed the 1969-70 season.
Green recovered and returned the following year with the Bruins, then played seven seasons in the World Hockey Association, but he was never the same player again.