HOUSTON — Lamar Odom suffered back spasms after a hard fall with 6:01 left in the third quarter of Game 4 today. He was driving to the basket when Houston’s Shane Battier intercepted him in the paint. They collided. Odom was charged with an offensive foul after falling onto his back. He left the game and, minutes later, left for the locker room. He will undergo tests and treatment today. His status for Game 5 on Tuesday is uncertain.