For wounds that may involve the joint you can consider doing a saline load test. Just like an arthrocentesis, a needle is introduced into the joint. 150-200 ml of sterile saline is slowly infused while watching the laceration to see if the fluid leaks out, suggesting that the laceration and the joint communicate. Some providers add methylene blue but this has not been shown to improve sensitivity and may increase inflammation. Remember to remove all the fluid afterwards.