Celtics coach Brad Stevens said after the game that the initial test results were encouraging and being quickly released after undergoing additional tests bodes well for Walker.
However, his initial concussion-like symptoms will likely result in him being placed in the NBA's concussion protocol, which involves a series of tests and evaluations before he can return to action.
A player in the concussion protocol can't return to the floor until the following:
He is without concussion-related symptoms at rest.
He has been evaluated by a physician.
He has successfully completed the NBA return-to-participation exertion protocol.
A team physician has discussed the return-to-participation process and decision with the director of the NBA concussion program.
Because every player with concussion-like symptoms is different, the decision as to when a player is fit to return will be made by the team physician.
And that decision will be based on Walker meeting certain benchmarks that give a clear indication that he's ready to resume playing and be free of concussion-like symptoms.
From the NBA's media website, here's a closer look at the NBA's return-to-participation protocol:
A player diagnosed with a concussion should be regularly monitored by a member of the team's medical staff for 24 hours for the evolution of symptoms. The player may not begin the return-to-participation exertion process until 24 hours after the time of injury. The initiation of the return-to-participation exertion process is determined by a team physician.
The return to participation process involves several steps of increasing exertion – from a stationary bike to jogging, to agility work, to non-contact team drills.
Each exertion stage should be monitored by the team's medical staff. With each step, a focused neurological examination is performed and a player must be symptom-free to move to the next step. If a player is not symptom-free, he stops until he is and begins again at the last step he passed without any symptoms.
It's important to note that there is no timeframe to complete the process. Each injury and player is different and recovery time can vary in each case.
While there's no immediate timetable for when Walker will return, it's almost a given he'll miss some time if he winds up in the league's concussion protocol. The Celtics play again Monday at home against the Sacramento Kings.
Last spring, Gordon Hayward took a blow to the head in a March 16 game against Atlanta and missed three games while being in the league's concussion protocol. Teammate Jaylen Brown suffered a concussion on March 22, 2018, following a hard fall on his back after a dunk in Minnesota. He was out for six games.
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