Best Massage I've had was at SB Thai. Its in Walsall but five minutes drive from the motorway. Never had anything extra, but the massage was so good I didn't care.
A review will follow but I had an excellent massage with Sophia at the relax centre in Erdington. There was a finish.
Whether these massages were medically approved for sciatica I don;t know, but they certainly had therpeutic effects for me, but my ailments weren't the same as yours.