Injured Athletes should be cleared by independent doctors before they can return playing. It happens a lot where doctors that are paid by specific teams will clear a player before they are healthy because the team is putting pressure on them to do so. The pressure may include extra income or even losing their job if they do not clear the player. If it was a rule where injured players needed an outside doctor to clear them to play, hopefully it will end career ending injuries to players that returned before they were healthy enough to play.
Team doctors are probably concerned with the overall condition of the team, rather than the overall condition of an individual player. So, when making the decision for a player to return to play or not, a team doctor will probably make a decision that will enable to the team to win, even if this means that the player may be playing when they are not completely ready or able to play.
This should be an obvious yes because a team doctor could easily be influenced or be forced into a decision not his own simply because he/she is the "team" doctor.
It's true that the health of the players are more important. But there are instances when it may be overlooked for the "greater good". Let me give a scenario. A city long without a professional title in any major sports is locked in a championship series with an equally talented team. Game seven is coming. However, a role player got injured last game. The doctor say that the player isn't cleared to play for the pivotal game for there is a small chance that the injury would turn into a major problem, possibly a career-ending one if forced to play. The team might lose several key players to free agency next season and the upcoming draft is deep.
If that's the case I unfortunately think that most GM's would make that said player go through the game. More so if the player is already on the decline and probably on his last hurrah.
In times like these there should be a panel of doctors appointed by the league and the GM's. This panel should come up with a majority decision for a player to be cleared to play.
With the recent injury if Klay Thompson there has been renewed interest in opening the debate on player rights. Players currently have to go through a medical vetting process to get cleared to return to play. While there are many positives to this the players themselves should have the final decision on whether they are ready to return to play or not.
Athletes are adults who, while not doctors, are very familiar with the kinds of injuries and symptoms associated with injuries in their sports. After consulting the team doctor, the athletes can decide for themselves if they want a second opinion. And they shouldn't be prevented contractually from doing that if they think it necessary.