Yes and No. Generally, a subpoena (with signed Court Order) will get the records delivered to the Court under seal for the Court to review and determine their relevancy. (see HIPPA) However, in a PI case medical records are clearly relevant and should be freely exchanged between the sides. Generally speaking a HIPPA compliant release is signed by the Plaintiff. Then a Notice of records deposition is served on the caregivers, who then gather and send the records. (At the requestor's cost) .
Generally, the plaintiff's medical records are discoverable in a personal injury suit. After all they are the basis of the claim for financial relief. If you have an insurance carrier and the carrier has provided you with counsel, ask your lawyer to get the records. I'll bet he/she already has them. If not, the records will soon be in your lawyer's hands. If you don't have insurance, hire an attorney on your own. Don't play in the courthouse if you don't know the rules.
Yes, but only if the party issuing the subpoena has a valid HIPPA compliant release signed by the plaintiff. Without a release no medical provider is permitted to prelease any medical records. The defendant may obtain any medical records related to the crash or related to any pre-existing conditions. If you disagree with the defendants getting this info your lawyer should ask the court to prohibit the discovery of this evidence,