Permanent grounding?
It is in theory possible for somebody never to act as pilot in command again on the simple basis of not being able to pass a medical.
I know of a student pilot who, 25 years ago decided to descend on the downwind leg to nought feet and buzz the motorway traffic.
He got nicked when he landed and thereafter failed at every attempt to renew his medical for pschycological reasons.
In his case, he waited until recently to reapply - his CAA file must have been lost because he now has a medical again (keep your heads down in Kent guys!)
So - on the basis that no AME will issue, and surely no one will insure him - he will not fly again as a pilot.
Rehabilitation of offenders is OK in law but we are talking about a medical problem here. The helicopter pilot clearly suffers from a jammed head occasionaly so shouldn't be allowed to fly. Ever.