Lacerated spleen injury. do they have to remove it?

Usually not: Most spleen injuries will heal without any intervention. Patients with a spleen injury are usually admitted to the hospital & watched closely. If the spleen continues to bleed, then there are a couple of options--a catheter may be used to embolize the artery feeding the spleen and cut off the blood flow, or surgery may be done to simply remove the spleen.

Depends: Most splenic injuries are able to be managed non-operatively. Some injuries may require an operation. Sometimes it can be repaired, or part of it removed (very rare). Many times splenic embolization is done by an interventional radiologist, who threads a catheter into the arteries to deposit "coils" or "foam" that stops the blood flow to the damaged area of the spleen.